Merge branch 'i2c/for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:
"Features:

- new drivers: Renesas EMEV2, register based MUX, NXP LPC2xxx
- core: scans DT and assigns wakeup interrupts. no driver changes needed.
- core: some refcouting issues fixed and better API for that
- core: new helper function for best effort block read emulation
- slave framework: proper DT bindings and userspace instantiation
- some bigger work for xiic, pxa, omap drivers

.. and quite a number of smaller driver fixes, cleanups, improvements"

* 'i2c/for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (65 commits)
i2c: mux: reg Change ioread endianness for readback
i2c: mux: reg: fix compilation warnings
i2c: mux: reg: simplify register size checking
i2c: muxes: fix leaked i2c adapter device node references
i2c: allow specifying separate wakeup interrupt in device tree
of/irq: export of_get_irq_byname()
i2c: xgene-slimpro: dma_mapping_error() doesn't return an error code
i2c: Replace I2C_CROS_EC_TUNNEL dependency
eeprom: at24: use i2c_smbus_read_i2c_block_data_or_emulated
i2c: core: Add support for best effort block read emulation
i2c: lpc2k: add driver
i2c: mux: Add register-based mux i2c-mux-reg
i2c: dt: describe generic bindings
i2c: slave: print warning if slave flag not set
i2c: support 10 bit and slave addresses in sysfs 'new_device'
i2c: take address space into account when checking for used addresses
i2c: apply DT flags when probing
i2c: make address check indpendent from client struct
i2c: rename address check functions
i2c: apply address offset for slaves, too
...

Documentation/devicetree/bindings/i2c/i2c-cadence.txt

···
 
 Required properties:
   - reg: Physical base address and size of the controller's register area.
-  - compatible: Compatibility string. Must be 'cdns,i2c-r1p10'.
+  - compatible: Should contain one of:
+		* "cdns,i2c-r1p10"
+		Note:	Use this when cadence i2c controller version 1.0 is used.
+		* "cdns,i2c-r1p14"
+		Note:	Use this when cadence i2c controller version 1.4 is used.
   - clocks: Input clock specifier. Refer to common clock bindings.
   - interrupts: Interrupt specifier. Refer to interrupt bindings.
   - #address-cells: Should be 1.

Documentation/devicetree/bindings/i2c/i2c-emev2.txt

···
+Device tree configuration for Renesas EMEV2 IIC controller
+
+Required properties:
+- compatible      : "renesas,iic-emev2"
+- reg             : address start and address range size of device
+- interrupts      : specifier for the IIC controller interrupt
+- clocks          : phandle to the IP core SCLK
+- clock-names     : must be "sclk"
+- #address-cells  : should be <1>
+- #size-cells     : should be <0>
+
+Example:
+
+	iic0: i2c@e0070000 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "renesas,iic-emev2";
+		reg = <0xe0070000 0x28>;
+		interrupts = <0 32 IRQ_TYPE_EDGE_RISING>;
+		clocks = <&iic0_sclk>;
+		clock-names = "sclk";
+	};

Documentation/devicetree/bindings/i2c/i2c-lpc2k.txt

···
+NXP I2C controller for LPC2xxx/178x/18xx/43xx
+
+Required properties:
+ - compatible: must be "nxp,lpc1788-i2c"
+ - reg: physical address and length of the device registers
+ - interrupts: a single interrupt specifier
+ - clocks: clock for the device
+ - #address-cells: should be <1>
+ - #size-cells: should be <0>
+
+Optional properties:
+- clock-frequency: the desired I2C bus clock frequency in Hz; in
+  absence of this property the default value is used (100 kHz).
+
+Example:
+i2c0: i2c@400a1000 {
+	compatible = "nxp,lpc1788-i2c";
+	reg = <0x400a1000 0x1000>;
+	interrupts = <18>;
+	clocks = <&ccu1 CLK_APB1_I2C0>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+};
+
+&i2c0 {
+	clock-frequency = <400000>;
+
+	lm75@48 {
+		compatible = "nxp,lm75";
+		reg = <0x48>;
+	};
+};
+

Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt

···
+Register-based I2C Bus Mux
+
+This binding describes an I2C bus multiplexer that uses a single register
+to route the I2C signals.
+
+Required properties:
+- compatible: i2c-mux-reg
+- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
+  port is connected to.
+* Standard I2C mux properties. See mux.txt in this directory.
+* I2C child bus nodes. See mux.txt in this directory.
+
+Optional properties:
+- reg: this pair of <offset size> specifies the register to control the mux.
+  The <offset size> depends on its parent node. It can be any memory-mapped
+  address. The size must be either 1, 2, or 4 bytes. If reg is omitted, the
+  resource of this device will be used.
+- little-endian: The existence indicates the register is in little endian.
+- big-endian: The existence indicates the register is in big endian.
+  If both little-endian and big-endian are omitted, the endianness of the
+  CPU will be used.
+- write-only: The existence indicates the register is write-only.
+- idle-state: value to set the muxer to when idle. When no value is
+  given, it defaults to the last value used.
+
+Whenever an access is made to a device on a child bus, the value set
+in the revelant node's reg property will be output to the register.
+
+If an idle state is defined, using the idle-state (optional) property,
+whenever an access is not being made to a device on a child bus, the
+register will be set according to the idle value.
+
+If an idle state is not defined, the most recently used value will be
+left programmed into the register.
+
+Example of a mux on PCIe card, the host is a powerpc SoC (big endian):
+
+	i2c-mux {
+		/* the <offset size> depends on the address translation
+		 * of the parent device. If omitted, device resource
+		 * will be used instead. The size is to determine
+		 * whether iowrite32, iowrite16, or iowrite8 will be used.
+		 */
+		reg = <0x6028 0x4>;
+		little-endian;		/* little endian register on PCIe */
+		compatible = "i2c-mux-reg";
+		#address-cells = <1>;
+		#size-cells = <0>;
+		i2c-parent = <&i2c1>;
+		i2c@0 {
+			reg = <0>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			si5338: clock-generator@70 {
+				compatible = "silabs,si5338";
+				reg = <0x70>;
+				/* other stuff */
+			};
+		};
+
+		i2c@1 {
+			/* data is written using iowrite32 */
+			reg = <1>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			si5338: clock-generator@70 {
+				compatible = "silabs,si5338";
+				reg = <0x70>;
+				/* other stuff */
+			};
+		};
+	};

Documentation/devicetree/bindings/i2c/i2c.txt

···
+Generic device tree bindings for I2C busses
+===========================================
+
+This document describes generic bindings which can be used to describe I2C
+busses in a device tree.
+
+Required properties
+-------------------
+
+- #address-cells  - should be <1>. Read more about addresses below.
+- #size-cells     - should be <0>.
+- compatible      - name of I2C bus controller following generic names
+		    recommended practice.
+
+For other required properties e.g. to describe register sets,
+clocks, etc. check the binding documentation of the specific driver.
+
+The cells properties above define that an address of children of an I2C bus
+are described by a single value. This is usually a 7 bit address. However,
+flags can be attached to the address. I2C_TEN_BIT_ADDRESS is used to mark a 10
+bit address. It is needed to avoid the ambiguity between e.g. a 7 bit address
+of 0x50 and a 10 bit address of 0x050 which, in theory, can be on the same bus.
+Another flag is I2C_OWN_SLAVE_ADDRESS to mark addresses on which we listen to
+be devices ourselves.
+
+Optional properties
+-------------------
+
+These properties may not be supported by all drivers. However, if a driver
+wants to support one of the below features, it should adapt the bindings below.
+
+- clock-frequency	- frequency of bus clock in Hz.
+- wakeup-source		- device can be used as a wakeup source.
+
+- interrupts		- interrupts used by the device.
+- interrupt-names	- "irq" and "wakeup" names are recognized by I2C core,
+			  other names are left to individual drivers.
+
+Binding may contain optional "interrupts" property, describing interrupts
+used by the device. I2C core will assign "irq" interrupt (or the very first
+interrupt if not using interrupt names) as primary interrupt for the slave.
+
+Also, if device is marked as a wakeup source, I2C core will set up "wakeup"
+interrupt for the device. If "wakeup" interrupt name is not present in the
+binding, then primary interrupt will be used as wakeup interrupt.

Documentation/devicetree/bindings/i2c/trivial-devices.txt

···
 stm,m41t62		Serial real-time clock (RTC) with alarm
 stm,m41t80		M41T80 - SERIAL ACCESS RTC WITH ALARMS
 taos,tsl2550		Ambient Light Sensor with SMBUS/Two Wire Serial Interface
+ti,ads7828		8-Channels, 12-bit ADC
+ti,ads7830		8-Channels, 8-bit ADC
 ti,tsc2003		I2C Touch-Screen Controller
 ti,tmp102		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface
 ti,tmp103		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface

Documentation/i2c/busses/i2c-parport

···
  * (type=5) Analog Devices evaluation boards: ADM1025, ADM1030, ADM1031
  * (type=6) Barco LPT->DVI (K5800236) adapter
  * (type=7) One For All JP1 parallel port adapter
+ * (type=8) VCT-jig
 
 These devices use different pinout configurations, so you have to tell
 the driver what you have, using the type module parameter. There is no

Documentation/i2c/slave-interface

···
 ===========
 
 I2C slave backends behave like standard I2C clients. So, you can instantiate
-them as described in the document 'instantiating-devices'. A quick example for
-instantiating the slave-eeprom driver from userspace at address 0x64 on bus 1:
+them as described in the document 'instantiating-devices'. The only difference
+is that i2c slave backends have their own address space. So, you have to add
+0x1000 to the address you would originally request. An example for
+instantiating the slave-eeprom driver from userspace at the 7 bit address 0x64
+on bus 1:
 
-  # echo slave-24c02 0x64 > /sys/bus/i2c/devices/i2c-1/new_device
+  # echo slave-24c02 0x1064 > /sys/bus/i2c/devices/i2c-1/new_device
 
 Each backend should come with separate documentation to describe its specific
 behaviour and setup.

Documentation/i2c/ten-bit-addresses

···
 addresses, and an extended set of 10 bit addresses. The sets of addresses
 do not intersect: the 7 bit address 0x10 is not the same as the 10 bit
 address 0x10 (though a single device could respond to both of them).
+To avoid ambiguity, the user sees 10 bit addresses mapped to a different
+address space, namely 0xa000-0xa3ff. The leading 0xa (= 10) represents the
+10 bit mode. This is used for creating device names in sysfs. It is also
+needed when instantiating 10 bit devices via the new_device file in sysfs.
 
 I2C messages to and from 10-bit address devices have a different format.
 See the I2C specification for the details.

drivers/clk/shmobile/clk-emev2.c

···
 #define USIBU1_RSTCTRL 0x0ac
 #define USIBU2_RSTCTRL 0x0b0
 #define USIBU3_RSTCTRL 0x0b4
+#define IIC0_RSTCTRL 0x0dc
+#define IIC1_RSTCTRL 0x0e0
 #define STI_RSTCTRL 0x124
 #define STI_CLKSEL 0x688
 
···
 	emev2_smu_write(2, USIBU1_RSTCTRL);
 	emev2_smu_write(2, USIBU2_RSTCTRL);
 	emev2_smu_write(2, USIBU3_RSTCTRL);
+
+	/* deassert reset for IIC0->IIC1 */
+	emev2_smu_write(1, IIC0_RSTCTRL);
+	emev2_smu_write(1, IIC1_RSTCTRL);
 }
 
 static void __init emev2_smu_clkdiv_init(struct device_node *np)

drivers/i2c/busses/Kconfig

···
 	  ML7213/ML7223/ML7831 is companion chip for Intel Atom E6xx series.
 	  ML7213/ML7223/ML7831 is completely compatible for Intel EG20T PCH.
 
+config I2C_EMEV2
+	tristate "EMMA Mobile series I2C adapter"
+	depends on HAVE_CLK
+	help
+	  If you say yes to this option, support will be included for the
+	  I2C interface on the Renesas Electronics EM/EV family of processors.
+
 config I2C_EXYNOS5
 	tristate "Exynos5 high-speed I2C driver"
 	depends on ARCH_EXYNOS && OF
···
 
 	  This driver can also be built as a module. If so, the module
 	  will be called i2c-kempld.
+
+config I2C_LPC2K
+	tristate "I2C bus support for NXP LPC2K/LPC178x/18xx/43xx"
+	depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
+	help
+	  This driver supports the I2C interface found several NXP
+	  devices including LPC2xxx, LPC178x/7x and LPC18xx/43xx.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-lpc2k.
 
 config I2C_MESON
 	tristate "Amlogic Meson I2C controller"
···
 
 config I2C_CROS_EC_TUNNEL
 	tristate "ChromeOS EC tunnel I2C bus"
-	depends on CROS_EC_PROTO
+	depends on MFD_CROS_EC
 	help
 	  If you say yes here you get an I2C bus that will tunnel i2c commands
 	  through to the other side of the ChromeOS EC to the i2c bus

drivers/i2c/busses/Makefile

···
 obj-$(CONFIG_I2C_DIGICOLOR)	+= i2c-digicolor.o
 obj-$(CONFIG_I2C_EFM32)		+= i2c-efm32.o
 obj-$(CONFIG_I2C_EG20T)		+= i2c-eg20t.o
+obj-$(CONFIG_I2C_EMEV2)		+= i2c-emev2.o
 obj-$(CONFIG_I2C_EXYNOS5)	+= i2c-exynos5.o
 obj-$(CONFIG_I2C_GPIO)		+= i2c-gpio.o
 obj-$(CONFIG_I2C_HIGHLANDER)	+= i2c-highlander.o
···
 obj-$(CONFIG_I2C_IOP3XX)	+= i2c-iop3xx.o
 obj-$(CONFIG_I2C_JZ4780)	+= i2c-jz4780.o
 obj-$(CONFIG_I2C_KEMPLD)	+= i2c-kempld.o
+obj-$(CONFIG_I2C_LPC2K)		+= i2c-lpc2k.o
 obj-$(CONFIG_I2C_MESON)		+= i2c-meson.o
 obj-$(CONFIG_I2C_MPC)		+= i2c-mpc.o
 obj-$(CONFIG_I2C_MT65XX)	+= i2c-mt65xx.o

drivers/i2c/busses/i2c-cadence.c

···
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/of.h>
 
 /* Register offsets for the I2C device. */
 #define CDNS_I2C_CR_OFFSET		0x00 /* Control Register, RW */
···
 
 #define CDNS_I2C_TIMEOUT_MAX	0xFF
 
+#define CDNS_I2C_BROKEN_HOLD_BIT	BIT(0)
+
 #define cdns_i2c_readreg(offset)       readl_relaxed(id->membase + offset)
 #define cdns_i2c_writereg(val, offset) writel_relaxed(val, id->membase + offset)
 
···
  * @bus_hold_flag:	Flag used in repeated start for clearing HOLD bit
  * @clk:		Pointer to struct clk
  * @clk_rate_change_nb:	Notifier block for clock rate changes
+ * @quirks:		flag for broken hold bit usage in r1p10
  */
 struct cdns_i2c {
 	void __iomem *membase;
···
 	unsigned int bus_hold_flag;
 	struct clk *clk;
 	struct notifier_block clk_rate_change_nb;
+	u32 quirks;
+};
+
+struct cdns_platform_data {
+	u32 quirks;
 };
 
 #define to_cdns_i2c(_nb)	container_of(_nb, struct cdns_i2c, \
···
 		cdns_i2c_writereg(reg & ~CDNS_I2C_CR_HOLD, CDNS_I2C_CR_OFFSET);
 }
 
+static inline bool cdns_is_holdquirk(struct cdns_i2c *id, bool hold_wrkaround)
+{
+	return (hold_wrkaround &&
+		(id->curr_recv_count == CDNS_I2C_FIFO_DEPTH + 1));
+}
+
 /**
  * cdns_i2c_isr - Interrupt handler for the I2C device
  * @irq:	irq number for the I2C device
···
 {
 	unsigned int isr_status, avail_bytes, updatetx;
 	unsigned int bytes_to_send;
+	bool hold_quirk;
 	struct cdns_i2c *id = ptr;
 	/* Signal completion only after everything is updated */
 	int done_flag = 0;
···
 	if (id->recv_count > id->curr_recv_count)
 		updatetx = 1;
 
+	hold_quirk = (id->quirks & CDNS_I2C_BROKEN_HOLD_BIT) && updatetx;
+
 	/* When receiving, handle data interrupt and completion interrupt */
 	if (id->p_recv_buf &&
 	    ((isr_status & CDNS_I2C_IXR_COMP) ||
···
 			id->recv_count--;
 			id->curr_recv_count--;
 
-			if (updatetx &&
-			    (id->curr_recv_count == CDNS_I2C_FIFO_DEPTH + 1))
+			if (cdns_is_holdquirk(id, hold_quirk))
 				break;
 		}
 
···
 		 * maintain transfer size non-zero while performing a large
 		 * receive operation.
 		 */
-		if (updatetx &&
-		    (id->curr_recv_count == CDNS_I2C_FIFO_DEPTH + 1)) {
+		if (cdns_is_holdquirk(id, hold_quirk)) {
 			/* wait while fifo is full */
 			while (cdns_i2c_readreg(CDNS_I2C_XFER_SIZE_OFFSET) !=
 			       (id->curr_recv_count - CDNS_I2C_FIFO_DEPTH))
···
 				cdns_i2c_writereg(id->recv_count -
 						  CDNS_I2C_FIFO_DEPTH,
 						  CDNS_I2C_XFER_SIZE_OFFSET);
+				id->curr_recv_count = id->recv_count;
+			}
+		} else if (id->recv_count && !hold_quirk &&
+						!id->curr_recv_count) {
+
+			/* Set the slave address in address register*/
+			cdns_i2c_writereg(id->p_msg->addr & CDNS_I2C_ADDR_MASK,
+						CDNS_I2C_ADDR_OFFSET);
+
+			if (id->recv_count > CDNS_I2C_TRANSFER_SIZE) {
+				cdns_i2c_writereg(CDNS_I2C_TRANSFER_SIZE,
+						CDNS_I2C_XFER_SIZE_OFFSET);
+				id->curr_recv_count = CDNS_I2C_TRANSFER_SIZE;
+			} else {
+				cdns_i2c_writereg(id->recv_count,
+						CDNS_I2C_XFER_SIZE_OFFSET);
 				id->curr_recv_count = id->recv_count;
 			}
 		}
···
 	int ret, count;
 	u32 reg;
 	struct cdns_i2c *id = adap->algo_data;
+	bool hold_quirk;
 
 	/* Check if the bus is free */
 	if (cdns_i2c_readreg(CDNS_I2C_SR_OFFSET) & CDNS_I2C_SR_BA)
 		return -EAGAIN;
 
+	hold_quirk = !!(id->quirks & CDNS_I2C_BROKEN_HOLD_BIT);
 	/*
 	 * Set the flag to one when multiple messages are to be
 	 * processed with a repeated start.
···
 		 * followed by any other message, an error is returned
 		 * indicating that this sequence is not supported.
 		 */
-		for (count = 0; count < num - 1; count++) {
+		for (count = 0; (count < num - 1 && hold_quirk); count++) {
 			if (msgs[count].flags & I2C_M_RD) {
 				dev_warn(adap->dev.parent,
 					 "Can't do repeated start after a receive message\n");
···
 static SIMPLE_DEV_PM_OPS(cdns_i2c_dev_pm_ops, cdns_i2c_suspend,
 			 cdns_i2c_resume);
 
+static const struct cdns_platform_data r1p10_i2c_def = {
+	.quirks = CDNS_I2C_BROKEN_HOLD_BIT,
+};
+
+static const struct of_device_id cdns_i2c_of_match[] = {
+	{ .compatible = "cdns,i2c-r1p10", .data = &r1p10_i2c_def },
+	{ .compatible = "cdns,i2c-r1p14",},
+	{ /* end of table */ }
+};
+MODULE_DEVICE_TABLE(of, cdns_i2c_of_match);
+
 /**
  * cdns_i2c_probe - Platform registration call
  * @pdev:	Handle to the platform device structure
···
 	struct resource *r_mem;
 	struct cdns_i2c *id;
 	int ret;
+	const struct of_device_id *match;
 
 	id = devm_kzalloc(&pdev->dev, sizeof(*id), GFP_KERNEL);
 	if (!id)
 		return -ENOMEM;
 
 	platform_set_drvdata(pdev, id);
+
+	match = of_match_node(cdns_i2c_of_match, pdev->dev.of_node);
+	if (match && match->data) {
+		const struct cdns_platform_data *data = match->data;
+		id->quirks = data->quirks;
+	}
 
 	r_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	id->membase = devm_ioremap_resource(&pdev->dev, r_mem);
···
 
 	id->irq = platform_get_irq(pdev, 0);
 
+	id->adap.owner = THIS_MODULE;
 	id->adap.dev.of_node = pdev->dev.of_node;
 	id->adap.algo = &cdns_i2c_algo;
 	id->adap.timeout = CDNS_I2C_TIMEOUT;
···
 
 	return 0;
 }
-
-static const struct of_device_id cdns_i2c_of_match[] = {
-	{ .compatible = "cdns,i2c-r1p10", },
-	{ /* end of table */ }
-};
-MODULE_DEVICE_TABLE(of, cdns_i2c_of_match);
 
 static struct platform_driver cdns_i2c_drv = {
 	.driver = {

drivers/i2c/busses/i2c-designware-core.c

···
 
 	enabled = dw_readl(dev, DW_IC_ENABLE);
 	stat = dw_readl(dev, DW_IC_RAW_INTR_STAT);
-	dev_dbg(dev->dev, "%s:  %s enabled= 0x%x stat=0x%x\n", __func__,
-		dev->adapter.name, enabled, stat);
+	dev_dbg(dev->dev, "%s: enabled=%#x stat=%#x\n", __func__, enabled, stat);
 	if (!enabled || !(stat & ~DW_IC_INTR_ACTIVITY))
 		return IRQ_NONE;
 

drivers/i2c/busses/i2c-designware-pcidrv.c

···
 
 	snprintf(adap->name, sizeof(adap->name), "i2c-designware-pci");
 
-	r = devm_request_irq(&pdev->dev, pdev->irq, i2c_dw_isr, IRQF_SHARED,
-			adap->name, dev);
+	r = devm_request_irq(&pdev->dev, pdev->irq, i2c_dw_isr,
+			IRQF_SHARED | IRQF_COND_SUSPEND, adap->name, dev);
 	if (r) {
 		dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
 		return r;

drivers/i2c/busses/i2c-emev2.c

···
+/*
+ * I2C driver for the Renesas EMEV2 SoC
+ *
+ * Copyright (C) 2015 Wolfram Sang <[e-mail]>
+ * Copyright 2013 Codethink Ltd.
+ * Copyright 2010-2015 Renesas Electronics Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+
+/* I2C Registers */
+#define I2C_OFS_IICACT0		0x00	/* start */
+#define I2C_OFS_IIC0		0x04	/* shift */
+#define I2C_OFS_IICC0		0x08	/* control */
+#define I2C_OFS_SVA0		0x0c	/* slave address */
+#define I2C_OFS_IICCL0		0x10	/* clock select */
+#define I2C_OFS_IICX0		0x14	/* extension */
+#define I2C_OFS_IICS0		0x18	/* status */
+#define I2C_OFS_IICSE0		0x1c	/* status For emulation */
+#define I2C_OFS_IICF0		0x20	/* IIC flag */
+
+/* I2C IICACT0 Masks */
+#define I2C_BIT_IICE0		0x0001
+
+/* I2C IICC0 Masks */
+#define I2C_BIT_LREL0		0x0040
+#define I2C_BIT_WREL0		0x0020
+#define I2C_BIT_SPIE0		0x0010
+#define I2C_BIT_WTIM0		0x0008
+#define I2C_BIT_ACKE0		0x0004
+#define I2C_BIT_STT0		0x0002
+#define I2C_BIT_SPT0		0x0001
+
+/* I2C IICCL0 Masks */
+#define I2C_BIT_SMC0		0x0008
+#define I2C_BIT_DFC0		0x0004
+
+/* I2C IICSE0 Masks */
+#define I2C_BIT_MSTS0		0x0080
+#define I2C_BIT_ALD0		0x0040
+#define I2C_BIT_EXC0		0x0020
+#define I2C_BIT_COI0		0x0010
+#define I2C_BIT_TRC0		0x0008
+#define I2C_BIT_ACKD0		0x0004
+#define I2C_BIT_STD0		0x0002
+#define I2C_BIT_SPD0		0x0001
+
+/* I2C IICF0 Masks */
+#define I2C_BIT_STCF		0x0080
+#define I2C_BIT_IICBSY		0x0040
+#define I2C_BIT_STCEN		0x0002
+#define I2C_BIT_IICRSV		0x0001
+
+struct em_i2c_device {
+	void __iomem *base;
+	struct i2c_adapter adap;
+	struct completion msg_done;
+	struct clk *sclk;
+};
+
+static inline void em_clear_set_bit(struct em_i2c_device *priv, u8 clear, u8 set, u8 reg)
+{
+	writeb((readb(priv->base + reg) & ~clear) | set, priv->base + reg);
+}
+
+static int em_i2c_wait_for_event(struct em_i2c_device *priv)
+{
+	unsigned long time_left;
+	int status;
+
+	reinit_completion(&priv->msg_done);
+
+	time_left = wait_for_completion_timeout(&priv->msg_done, priv->adap.timeout);
+
+	if (!time_left)
+		return -ETIMEDOUT;
+
+	status = readb(priv->base + I2C_OFS_IICSE0);
+	return status & I2C_BIT_ALD0 ? -EAGAIN : status;
+}
+
+static void em_i2c_stop(struct em_i2c_device *priv)
+{
+	/* Send Stop condition */
+	em_clear_set_bit(priv, 0, I2C_BIT_SPT0 | I2C_BIT_SPIE0, I2C_OFS_IICC0);
+
+	/* Wait for stop condition */
+	em_i2c_wait_for_event(priv);
+}
+
+static void em_i2c_reset(struct i2c_adapter *adap)
+{
+	struct em_i2c_device *priv = i2c_get_adapdata(adap);
+	int retr;
+
+	/* If I2C active */
+	if (readb(priv->base + I2C_OFS_IICACT0) & I2C_BIT_IICE0) {
+		/* Disable I2C operation */
+		writeb(0, priv->base + I2C_OFS_IICACT0);
+
+		retr = 1000;
+		while (readb(priv->base + I2C_OFS_IICACT0) == 1 && retr)
+			retr--;
+		WARN_ON(retr == 0);
+	}
+
+	/* Transfer mode set */
+	writeb(I2C_BIT_DFC0, priv->base + I2C_OFS_IICCL0);
+
+	/* Can Issue start without detecting a stop, Reservation disabled. */
+	writeb(I2C_BIT_STCEN | I2C_BIT_IICRSV, priv->base + I2C_OFS_IICF0);
+
+	/* I2C enable, 9 bit interrupt mode */
+	writeb(I2C_BIT_WTIM0, priv->base + I2C_OFS_IICC0);
+
+	/* Enable I2C operation */
+	writeb(I2C_BIT_IICE0, priv->base + I2C_OFS_IICACT0);
+
+	retr = 1000;
+	while (readb(priv->base + I2C_OFS_IICACT0) == 0 && retr)
+		retr--;
+	WARN_ON(retr == 0);
+}
+
+static int __em_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msg,
+				int stop)
+{
+	struct em_i2c_device *priv = i2c_get_adapdata(adap);
+	int count, status, read = !!(msg->flags & I2C_M_RD);
+
+	/* Send start condition */
+	em_clear_set_bit(priv, 0, I2C_BIT_ACKE0 | I2C_BIT_WTIM0, I2C_OFS_IICC0);
+	em_clear_set_bit(priv, 0, I2C_BIT_STT0, I2C_OFS_IICC0);
+
+	/* Send slave address and R/W type */
+	writeb((msg->addr << 1) | read, priv->base + I2C_OFS_IIC0);
+
+	/* Wait for transaction */
+	status = em_i2c_wait_for_event(priv);
+	if (status < 0)
+		goto out_reset;
+
+	/* Received NACK (result of setting slave address and R/W) */
+	if (!(status & I2C_BIT_ACKD0)) {
+		em_i2c_stop(priv);
+		goto out;
+	}
+
+	/* Extra setup for read transactions */
+	if (read) {
+		/* 8 bit interrupt mode */
+		em_clear_set_bit(priv, I2C_BIT_WTIM0, I2C_BIT_ACKE0, I2C_OFS_IICC0);
+		em_clear_set_bit(priv, I2C_BIT_WTIM0, I2C_BIT_WREL0, I2C_OFS_IICC0);
+
+		/* Wait for transaction */
+		status = em_i2c_wait_for_event(priv);
+		if (status < 0)
+			goto out_reset;
+	}
+
+	/* Send / receive data */
+	for (count = 0; count < msg->len; count++) {
+		if (read) { /* Read transaction */
+			msg->buf[count] = readb(priv->base + I2C_OFS_IIC0);
+			em_clear_set_bit(priv, 0, I2C_BIT_WREL0, I2C_OFS_IICC0);
+
+		} else { /* Write transaction */
+			/* Received NACK */
+			if (!(status & I2C_BIT_ACKD0)) {
+				em_i2c_stop(priv);
+				goto out;
+			}
+
+			/* Write data */
+			writeb(msg->buf[count], priv->base + I2C_OFS_IIC0);
+		}
+
+		/* Wait for R/W transaction */
+		status = em_i2c_wait_for_event(priv);
+		if (status < 0)
+			goto out_reset;
+	}
+
+	if (stop)
+		em_i2c_stop(priv);
+
+	return count;
+
+out_reset:
+	em_i2c_reset(adap);
+out:
+	return status < 0 ? status : -ENXIO;
+}
+
+static int em_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
+	int num)
+{
+	struct em_i2c_device *priv = i2c_get_adapdata(adap);
+	int ret, i;
+
+	if (readb(priv->base + I2C_OFS_IICF0) & I2C_BIT_IICBSY)
+		return -EAGAIN;
+
+	for (i = 0; i < num; i++) {
+		ret = __em_i2c_xfer(adap, &msgs[i], (i == (num - 1)));
+		if (ret < 0)
+			return ret;
+	}
+
+	/* I2C transfer completed */
+	return num;
+}
+
+static irqreturn_t em_i2c_irq_handler(int this_irq, void *dev_id)
+{
+	struct em_i2c_device *priv = dev_id;
+
+	complete(&priv->msg_done);
+	return IRQ_HANDLED;
+}
+
+static u32 em_i2c_func(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static struct i2c_algorithm em_i2c_algo = {
+	.master_xfer = em_i2c_xfer,
+	.functionality = em_i2c_func,
+};
+
+static int em_i2c_probe(struct platform_device *pdev)
+{
+	struct em_i2c_device *priv;
+	struct resource *r;
+	int irq, ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	strlcpy(priv->adap.name, "EMEV2 I2C", sizeof(priv->adap.name));
+
+	priv->sclk = devm_clk_get(&pdev->dev, "sclk");
+	if (IS_ERR(priv->sclk))
+		return PTR_ERR(priv->sclk);
+
+	clk_prepare_enable(priv->sclk);
+
+	priv->adap.timeout = msecs_to_jiffies(100);
+	priv->adap.retries = 5;
+	priv->adap.dev.parent = &pdev->dev;
+	priv->adap.algo = &em_i2c_algo;
+	priv->adap.owner = THIS_MODULE;
+	priv->adap.dev.of_node = pdev->dev.of_node;
+
+	init_completion(&priv->msg_done);
+
+	platform_set_drvdata(pdev, priv);
+	i2c_set_adapdata(&priv->adap, priv);
+
+	em_i2c_reset(&priv->adap);
+
+	irq = platform_get_irq(pdev, 0);
+	ret = devm_request_irq(&pdev->dev, irq, em_i2c_irq_handler, 0,
+				"em_i2c", priv);
+	if (ret)
+		goto err_clk;
+
+	ret = i2c_add_adapter(&priv->adap);
+
+	if (ret)
+		goto err_clk;
+
+	dev_info(&pdev->dev, "Added i2c controller %d, irq %d\n", priv->adap.nr, irq);
+
+	return 0;
+
+err_clk:
+	clk_disable_unprepare(priv->sclk);
+	return ret;
+}
+
+static int em_i2c_remove(struct platform_device *dev)
+{
+	struct em_i2c_device *priv = platform_get_drvdata(dev);
+
+	i2c_del_adapter(&priv->adap);
+	clk_disable_unprepare(priv->sclk);
+
+	return 0;
+}
+
+static const struct of_device_id em_i2c_ids[] = {
+	{ .compatible = "renesas,iic-emev2", },
+	{ }
+};
+
+static struct platform_driver em_i2c_driver = {
+	.probe = em_i2c_probe,
+	.remove = em_i2c_remove,
+	.driver = {
+		.name = "em-i2c",
+		.of_match_table = em_i2c_ids,
+	}
+};
+module_platform_driver(em_i2c_driver);
+
+MODULE_DESCRIPTION("EMEV2 I2C bus driver");
+MODULE_AUTHOR("Ian Molton and Wolfram Sang <[e-mail]>");
+MODULE_LICENSE("GPL v2");
+MODULE_DEVICE_TABLE(of, em_i2c_ids);

drivers/i2c/busses/i2c-lpc2k.c

···
+/*
+ * Copyright (C) 2011 NXP Semiconductors
+ *
+ * Code portions referenced from the i2x-pxa and i2c-pnx drivers
+ *
+ * Make SMBus byte and word transactions work on LPC178x/7x
+ * Copyright (c) 2012
+ * Alexander Potashev, Emcraft Systems, [e-mail]
+ * Anton Protopopov, Emcraft Systems, [e-mail]
+ *
+ * Copyright (C) 2015 Joachim Eastwood <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/time.h>
+
+/* LPC24xx register offsets and bits */
+#define LPC24XX_I2CONSET	0x00
+#define LPC24XX_I2STAT		0x04
+#define LPC24XX_I2DAT		0x08
+#define LPC24XX_I2ADDR		0x0c
+#define LPC24XX_I2SCLH		0x10
+#define LPC24XX_I2SCLL		0x14
+#define LPC24XX_I2CONCLR	0x18
+
+#define LPC24XX_AA		BIT(2)
+#define LPC24XX_SI		BIT(3)
+#define LPC24XX_STO		BIT(4)
+#define LPC24XX_STA		BIT(5)
+#define LPC24XX_I2EN		BIT(6)
+
+#define LPC24XX_STO_AA		(LPC24XX_STO | LPC24XX_AA)
+#define LPC24XX_CLEAR_ALL	(LPC24XX_AA | LPC24XX_SI | LPC24XX_STO | \
+				 LPC24XX_STA | LPC24XX_I2EN)
+
+/* I2C SCL clock has different duty cycle depending on mode */
+#define I2C_STD_MODE_DUTY		46
+#define I2C_FAST_MODE_DUTY		36
+#define I2C_FAST_MODE_PLUS_DUTY		38
+
+/*
+ * 26 possible I2C status codes, but codes applicable only
+ * to master are listed here and used in this driver
+ */
+enum {
+	M_BUS_ERROR		= 0x00,
+	M_START			= 0x08,
+	M_REPSTART		= 0x10,
+	MX_ADDR_W_ACK		= 0x18,
+	MX_ADDR_W_NACK		= 0x20,
+	MX_DATA_W_ACK		= 0x28,
+	MX_DATA_W_NACK		= 0x30,
+	M_DATA_ARB_LOST		= 0x38,
+	MR_ADDR_R_ACK		= 0x40,
+	MR_ADDR_R_NACK		= 0x48,
+	MR_DATA_R_ACK		= 0x50,
+	MR_DATA_R_NACK		= 0x58,
+	M_I2C_IDLE		= 0xf8,
+};
+
+struct lpc2k_i2c {
+	void __iomem		*base;
+	struct clk		*clk;
+	int			irq;
+	wait_queue_head_t	wait;
+	struct i2c_adapter	adap;
+	struct i2c_msg		*msg;
+	int			msg_idx;
+	int			msg_status;
+	int			is_last;
+};
+
+static void i2c_lpc2k_reset(struct lpc2k_i2c *i2c)
+{
+	/* Will force clear all statuses */
+	writel(LPC24XX_CLEAR_ALL, i2c->base + LPC24XX_I2CONCLR);
+	writel(0, i2c->base + LPC24XX_I2ADDR);
+	writel(LPC24XX_I2EN, i2c->base + LPC24XX_I2CONSET);
+}
+
+static int i2c_lpc2k_clear_arb(struct lpc2k_i2c *i2c)
+{
+	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
+
+	/*
+	 * If the transfer needs to abort for some reason, we'll try to
+	 * force a stop condition to clear any pending bus conditions
+	 */
+	writel(LPC24XX_STO, i2c->base + LPC24XX_I2CONSET);
+
+	/* Wait for status change */
+	while (readl(i2c->base + LPC24XX_I2STAT) != M_I2C_IDLE) {
+		if (time_after(jiffies, timeout)) {
+			/* Bus was not idle, try to reset adapter */
+			i2c_lpc2k_reset(i2c);
+			return -EBUSY;
+		}
+
+		cpu_relax();
+	}
+
+	return 0;
+}
+
+static void i2c_lpc2k_pump_msg(struct lpc2k_i2c *i2c)
+{
+	unsigned char data;
+	u32 status;
+
+	/*
+	 * I2C in the LPC2xxx series is basically a state machine.
+	 * Just run through the steps based on the current status.
+	 */
+	status = readl(i2c->base + LPC24XX_I2STAT);
+
+	switch (status) {
+	case M_START:
+	case M_REPSTART:
+		/* Start bit was just sent out, send out addr and dir */
+		data = i2c->msg->addr << 1;
+		if (i2c->msg->flags & I2C_M_RD)
+			data |= 1;
+
+		writel(data, i2c->base + LPC24XX_I2DAT);
+		writel(LPC24XX_STA, i2c->base + LPC24XX_I2CONCLR);
+		break;
+
+	case MX_ADDR_W_ACK:
+	case MX_DATA_W_ACK:
+		/*
+		 * Address or data was sent out with an ACK. If there is more
+		 * data to send, send it now
+		 */
+		if (i2c->msg_idx < i2c->msg->len) {
+			writel(i2c->msg->buf[i2c->msg_idx],
+			       i2c->base + LPC24XX_I2DAT);
+		} else if (i2c->is_last) {
+			/* Last message, send stop */
+			writel(LPC24XX_STO_AA, i2c->base + LPC24XX_I2CONSET);
+			writel(LPC24XX_SI, i2c->base + LPC24XX_I2CONCLR);
+			i2c->msg_status = 0;
+			disable_irq_nosync(i2c->irq);
+		} else {
+			i2c->msg_status = 0;
+			disable_irq_nosync(i2c->irq);
+		}
+
+		i2c->msg_idx++;
+		break;
+
+	case MR_ADDR_R_ACK:
+		/* Receive first byte from slave */
+		if (i2c->msg->len == 1) {
+			/* Last byte, return NACK */
+			writel(LPC24XX_AA, i2c->base + LPC24XX_I2CONCLR);
+		} else {
+			/* Not last byte, return ACK */
+			writel(LPC24XX_AA, i2c->base + LPC24XX_I2CONSET);
+		}
+
+		writel(LPC24XX_STA, i2c->base + LPC24XX_I2CONCLR);
+		break;
+
+	case MR_DATA_R_NACK:
+		/*
+		 * The I2C shows NACK status on reads, so we need to accept
+		 * the NACK as an ACK here. This should be ok, as the real
+		 * BACK would of been caught on the address write.
+		 */
+	case MR_DATA_R_ACK:
+		/* Data was received */
+		if (i2c->msg_idx < i2c->msg->len) {
+			i2c->msg->buf[i2c->msg_idx] =
+					readl(i2c->base + LPC24XX_I2DAT);
+		}
+
+		/* If transfer is done, send STOP */
+		if (i2c->msg_idx >= i2c->msg->len - 1 && i2c->is_last) {
+			writel(LPC24XX_STO_AA, i2c->base + LPC24XX_I2CONSET);
+			writel(LPC24XX_SI, i2c->base + LPC24XX_I2CONCLR);
+			i2c->msg_status = 0;
+		}
+
+		/* Message is done */
+		if (i2c->msg_idx >= i2c->msg->len - 1) {
+			i2c->msg_status = 0;
+			disable_irq_nosync(i2c->irq);
+		}
+
+		/*
+		 * One pre-last data input, send NACK to tell the slave that
+		 * this is going to be the last data byte to be transferred.
+		 */
+		if (i2c->msg_idx >= i2c->msg->len - 2) {
+			/* One byte left to receive - NACK */
+			writel(LPC24XX_AA, i2c->base + LPC24XX_I2CONCLR);
+		} else {
+			/* More than one byte left to receive - ACK */
+			writel(LPC24XX_AA, i2c->base + LPC24XX_I2CONSET);
+		}
+
+		writel(LPC24XX_STA, i2c->base + LPC24XX_I2CONCLR);
+		i2c->msg_idx++;
+		break;
+
+	case MX_ADDR_W_NACK:
+	case MX_DATA_W_NACK:
+	case MR_ADDR_R_NACK:
+		/* NACK processing is done */
+		writel(LPC24XX_STO_AA, i2c->base + LPC24XX_I2CONSET);
+		i2c->msg_status = -ENXIO;
+		disable_irq_nosync(i2c->irq);
+		break;
+
+	case M_DATA_ARB_LOST:
+		/* Arbitration lost */
+		i2c->msg_status = -EAGAIN;
+
+		/* Release the I2C bus */
+		writel(LPC24XX_STA | LPC24XX_STO, i2c->base + LPC24XX_I2CONCLR);
+		disable_irq_nosync(i2c->irq);
+		break;
+
+	default:
+		/* Unexpected statuses */
+		i2c->msg_status = -EIO;
+		disable_irq_nosync(i2c->irq);
+		break;
+	}
+
+	/* Exit on failure or all bytes transferred */
+	if (i2c->msg_status != -EBUSY)
+		wake_up(&i2c->wait);
+
+	/*
+	 * If `msg_status` is zero, then `lpc2k_process_msg()`
+	 * is responsible for clearing the SI flag.
+	 */
+	if (i2c->msg_status != 0)
+		writel(LPC24XX_SI, i2c->base + LPC24XX_I2CONCLR);
+}
+
+static int lpc2k_process_msg(struct lpc2k_i2c *i2c, int msgidx)
+{
+	/* A new transfer is kicked off by initiating a start condition */
+	if (!msgidx) {
+		writel(LPC24XX_STA, i2c->base + LPC24XX_I2CONSET);
+	} else {
+		/*
+		 * A multi-message I2C transfer continues where the
+		 * previous I2C transfer left off and uses the
+		 * current condition of the I2C adapter.
+		 */
+		if (unlikely(i2c->msg->flags & I2C_M_NOSTART)) {
+			WARN_ON(i2c->msg->len == 0);
+
+			if (!(i2c->msg->flags & I2C_M_RD)) {
+				/* Start transmit of data */
+				writel(i2c->msg->buf[0],
+				       i2c->base + LPC24XX_I2DAT);
+				i2c->msg_idx++;
+			}
+		} else {
+			/* Start or repeated start */
+			writel(LPC24XX_STA, i2c->base + LPC24XX_I2CONSET);
+		}
+
+		writel(LPC24XX_SI, i2c->base + LPC24XX_I2CONCLR);
+	}
+
+	enable_irq(i2c->irq);
+
+	/* Wait for transfer completion */
+	if (wait_event_timeout(i2c->wait, i2c->msg_status != -EBUSY,
+			       msecs_to_jiffies(1000)) == 0) {
+		disable_irq_nosync(i2c->irq);
+
+		return -ETIMEDOUT;
+	}
+
+	return i2c->msg_status;
+}
+
+static int i2c_lpc2k_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
+			  int msg_num)
+{
+	struct lpc2k_i2c *i2c = i2c_get_adapdata(adap);
+	int ret, i;
+	u32 stat;
+
+	/* Check for bus idle condition */
+	stat = readl(i2c->base + LPC24XX_I2STAT);
+	if (stat != M_I2C_IDLE) {
+		/* Something is holding the bus, try to clear it */
+		return i2c_lpc2k_clear_arb(i2c);
+	}
+
+	/* Process a single message at a time */
+	for (i = 0; i < msg_num; i++) {
+		/* Save message pointer and current message data index */
+		i2c->msg = &msgs[i];
+		i2c->msg_idx = 0;
+		i2c->msg_status = -EBUSY;
+		i2c->is_last = (i == (msg_num - 1));
+
+		ret = lpc2k_process_msg(i2c, i);
+		if (ret)
+			return ret;
+	}
+
+	return msg_num;
+}
+
+static irqreturn_t i2c_lpc2k_handler(int irq, void *dev_id)
+{
+	struct lpc2k_i2c *i2c = dev_id;
+
+	if (readl(i2c->base + LPC24XX_I2CONSET) & LPC24XX_SI) {
+		i2c_lpc2k_pump_msg(i2c);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+static u32 i2c_lpc2k_functionality(struct i2c_adapter *adap)
+{
+	/* Only emulated SMBus for now */
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm i2c_lpc2k_algorithm = {
+	.master_xfer	= i2c_lpc2k_xfer,
+	.functionality	= i2c_lpc2k_functionality,
+};
+
+static int i2c_lpc2k_probe(struct platform_device *pdev)
+{
+	struct lpc2k_i2c *i2c;
+	struct resource *res;
+	u32 bus_clk_rate;
+	u32 scl_high;
+	u32 clkrate;
+	int ret;
+
+	i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
+	if (!i2c)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	i2c->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(i2c->base))
+		return PTR_ERR(i2c->base);
+
+	i2c->irq = platform_get_irq(pdev, 0);
+	if (i2c->irq < 0) {
+		dev_err(&pdev->dev, "can't get interrupt resource\n");
+		return i2c->irq;
+	}
+
+	init_waitqueue_head(&i2c->wait);
+
+	i2c->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(i2c->clk)) {
+		dev_err(&pdev->dev, "error getting clock\n");
+		return PTR_ERR(i2c->clk);
+	}
+
+	ret = clk_prepare_enable(i2c->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to enable clock.\n");
+		return ret;
+	}
+
+	ret = devm_request_irq(&pdev->dev, i2c->irq, i2c_lpc2k_handler, 0,
+			       dev_name(&pdev->dev), i2c);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "can't request interrupt.\n");
+		goto fail_clk;
+	}
+
+	disable_irq_nosync(i2c->irq);
+
+	/* Place controller is a known state */
+	i2c_lpc2k_reset(i2c);
+
+	ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency",
+				   &bus_clk_rate);
+	if (ret)
+		bus_clk_rate = 100000; /* 100 kHz default clock rate */
+
+	clkrate = clk_get_rate(i2c->clk);
+	if (clkrate == 0) {
+		dev_err(&pdev->dev, "can't get I2C base clock\n");
+		ret = -EINVAL;
+		goto fail_clk;
+	}
+
+	/* Setup I2C dividers to generate clock with proper duty cycle */
+	clkrate = clkrate / bus_clk_rate;
+	if (bus_clk_rate <= 100000)
+		scl_high = (clkrate * I2C_STD_MODE_DUTY) / 100;
+	else if (bus_clk_rate <= 400000)
+		scl_high = (clkrate * I2C_FAST_MODE_DUTY) / 100;
+	else
+		scl_high = (clkrate * I2C_FAST_MODE_PLUS_DUTY) / 100;
+
+	writel(scl_high, i2c->base + LPC24XX_I2SCLH);
+	writel(clkrate - scl_high, i2c->base + LPC24XX_I2SCLL);
+
+	platform_set_drvdata(pdev, i2c);
+
+	i2c_set_adapdata(&i2c->adap, i2c);
+	i2c->adap.owner = THIS_MODULE;
+	strlcpy(i2c->adap.name, "LPC2K I2C adapter", sizeof(i2c->adap.name));
+	i2c->adap.algo = &i2c_lpc2k_algorithm;
+	i2c->adap.dev.parent = &pdev->dev;
+	i2c->adap.dev.of_node = pdev->dev.of_node;
+
+	ret = i2c_add_adapter(&i2c->adap);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to add adapter!\n");
+		goto fail_clk;
+	}
+
+	dev_info(&pdev->dev, "LPC2K I2C adapter\n");
+
+	return 0;
+
+fail_clk:
+	clk_disable_unprepare(i2c->clk);
+	return ret;
+}
+
+static int i2c_lpc2k_remove(struct platform_device *dev)
+{
+	struct lpc2k_i2c *i2c = platform_get_drvdata(dev);
+
+	i2c_del_adapter(&i2c->adap);
+	clk_disable_unprepare(i2c->clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int i2c_lpc2k_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct lpc2k_i2c *i2c = platform_get_drvdata(pdev);
+
+	clk_disable(i2c->clk);
+
+	return 0;
+}
+
+static int i2c_lpc2k_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct lpc2k_i2c *i2c = platform_get_drvdata(pdev);
+
+	clk_enable(i2c->clk);
+	i2c_lpc2k_reset(i2c);
+
+	return 0;
+}
+
+static const struct dev_pm_ops i2c_lpc2k_dev_pm_ops = {
+	.suspend_noirq = i2c_lpc2k_suspend,
+	.resume_noirq = i2c_lpc2k_resume,
+};
+
+#define I2C_LPC2K_DEV_PM_OPS (&i2c_lpc2k_dev_pm_ops)
+#else
+#define I2C_LPC2K_DEV_PM_OPS NULL
+#endif
+
+static const struct of_device_id lpc2k_i2c_match[] = {
+	{ .compatible = "nxp,lpc1788-i2c" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, lpc2k_i2c_match);
+
+static struct platform_driver i2c_lpc2k_driver = {
+	.probe	= i2c_lpc2k_probe,
+	.remove	= i2c_lpc2k_remove,
+	.driver	= {
+		.name		= "lpc2k-i2c",
+		.pm		= I2C_LPC2K_DEV_PM_OPS,
+		.of_match_table	= lpc2k_i2c_match,
+	},
+};
+module_platform_driver(i2c_lpc2k_driver);
+
+MODULE_AUTHOR("Kevin Wells <[e-mail]>");
+MODULE_DESCRIPTION("I2C driver for LPC2xxx devices");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:lpc2k-i2c");

drivers/i2c/busses/i2c-mt65xx.c

···
 #define I2C_DMA_START_EN		0x0001
 #define I2C_DMA_INT_FLAG_NONE		0x0000
 #define I2C_DMA_CLR_FLAG		0x0000
+#define I2C_DMA_HARD_RST		0x0002
 
 #define I2C_DEFAULT_SPEED		100000	/* hz */
 #define MAX_FS_MODE_SPEED		400000
···
 	OFFSET_INT_FLAG = 0x0,
 	OFFSET_INT_EN = 0x04,
 	OFFSET_EN = 0x08,
+	OFFSET_RST = 0x0c,
 	OFFSET_CON = 0x18,
 	OFFSET_TX_MEM_ADDR = 0x1c,
 	OFFSET_RX_MEM_ADDR = 0x20,
···
 		      I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN;
 	writew(control_reg, i2c->base + OFFSET_CONTROL);
 	writew(I2C_DELAY_LEN, i2c->base + OFFSET_DELAY_LEN);
+
+	writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST);
+	udelay(50);
+	writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
 }
 
 /*
···
 {
 	struct mtk_i2c *i2c = dev_id;
 	u16 restart_flag = 0;
+	u16 intr_stat;
 
 	if (i2c->dev_comp->auto_restart)
 		restart_flag = I2C_RS_TRANSFER;
 
-	i2c->irq_stat = readw(i2c->base + OFFSET_INTR_STAT);
-	writew(restart_flag | I2C_HS_NACKERR | I2C_ACKERR
-		| I2C_TRANSAC_COMP, i2c->base + OFFSET_INTR_STAT);
+	intr_stat = readw(i2c->base + OFFSET_INTR_STAT);
+	writew(intr_stat, i2c->base + OFFSET_INTR_STAT);
 
-	complete(&i2c->msg_complete);
+	/*
+	 * when occurs ack error, i2c controller generate two interrupts
+	 * first is the ack error interrupt, then the complete interrupt
+	 * i2c->irq_stat need keep the two interrupt value.
+	 */
+	i2c->irq_stat |= intr_stat;
+	if (i2c->irq_stat & (I2C_TRANSAC_COMP | restart_flag))
+		complete(&i2c->msg_complete);
 
 	return IRQ_HANDLED;
 }

drivers/i2c/busses/i2c-omap.c

···
 	[OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
 };
 
-static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
+static inline void omap_i2c_write_reg(struct omap_i2c_dev *omap,
 				      int reg, u16 val)
 {
-	writew_relaxed(val, i2c_dev->base +
-			(i2c_dev->regs[reg] << i2c_dev->reg_shift));
+	writew_relaxed(val, omap->base +
+			(omap->regs[reg] << omap->reg_shift));
 }
 
-static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
+static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *omap, int reg)
 {
-	return readw_relaxed(i2c_dev->base +
-				(i2c_dev->regs[reg] << i2c_dev->reg_shift));
+	return readw_relaxed(omap->base +
+				(omap->regs[reg] << omap->reg_shift));
 }
 
-static void __omap_i2c_init(struct omap_i2c_dev *dev)
+static void __omap_i2c_init(struct omap_i2c_dev *omap)
 {
 
-	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
+	omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0);
 
 	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
-	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
+	omap_i2c_write_reg(omap, OMAP_I2C_PSC_REG, omap->pscstate);
 
 	/* SCL low and high time values */
-	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
-	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
-	if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
-		omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
+	omap_i2c_write_reg(omap, OMAP_I2C_SCLL_REG, omap->scllstate);
+	omap_i2c_write_reg(omap, OMAP_I2C_SCLH_REG, omap->sclhstate);
+	if (omap->rev >= OMAP_I2C_REV_ON_3430_3530)
+		omap_i2c_write_reg(omap, OMAP_I2C_WE_REG, omap->westate);
 
 	/* Take the I2C module out of reset: */
-	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
+	omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 
 	/*
 	 * NOTE: right after setting CON_EN, STAT_BB could be 0 while the
···
 	 * Don't write to this register if the IE state is 0 as it can
 	 * cause deadlock.
 	 */
-	if (dev->iestate)
-		omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
+	if (omap->iestate)
+		omap_i2c_write_reg(omap, OMAP_I2C_IE_REG, omap->iestate);
 }
 
-static int omap_i2c_reset(struct omap_i2c_dev *dev)
+static int omap_i2c_reset(struct omap_i2c_dev *omap)
 {
 	unsigned long timeout;
 	u16 sysc;
 
-	if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
-		sysc = omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG);
+	if (omap->rev >= OMAP_I2C_OMAP1_REV_2) {
+		sysc = omap_i2c_read_reg(omap, OMAP_I2C_SYSC_REG);
 
 		/* Disable I2C controller before soft reset */
-		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
-			omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
+		omap_i2c_write_reg(omap, OMAP_I2C_CON_REG,
+			omap_i2c_read_reg(omap, OMAP_I2C_CON_REG) &
 				~(OMAP_I2C_CON_EN));
 
-		omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
+		omap_i2c_write_reg(omap, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
 		/* For some reason we need to set the EN bit before the
 		 * reset done bit gets set. */
 		timeout = jiffies + OMAP_I2C_TIMEOUT;
-		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
-		while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
+		omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
+		while (!(omap_i2c_read_reg(omap, OMAP_I2C_SYSS_REG) &
 			 SYSS_RESETDONE_MASK)) {
 			if (time_after(jiffies, timeout)) {
-				dev_warn(dev->dev, "timeout waiting "
+				dev_warn(omap->dev, "timeout waiting "
 						"for controller reset\n");
 				return -ETIMEDOUT;
 			}
···
 		}
 
 		/* SYSC register is cleared by the reset; rewrite it */
-		omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, sysc);
+		omap_i2c_write_reg(omap, OMAP_I2C_SYSC_REG, sysc);
 
-		if (dev->rev > OMAP_I2C_REV_ON_3430_3530) {
+		if (omap->rev > OMAP_I2C_REV_ON_3430_3530) {
 			/* Schedule I2C-bus monitoring on the next transfer */
-			dev->bb_valid = 0;
+			omap->bb_valid = 0;
 		}
 	}
 
 	return 0;
 }
 
-static int omap_i2c_init(struct omap_i2c_dev *dev)
+static int omap_i2c_init(struct omap_i2c_dev *omap)
 {
 	u16 psc = 0, scll = 0, sclh = 0;
 	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
···
 	unsigned long internal_clk = 0;
 	struct clk *fclk;
 
-	if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
+	if (omap->rev >= OMAP_I2C_REV_ON_3430_3530) {
 		/*
 		 * Enabling all wakup sources to stop I2C freezing on
 		 * WFI instruction.
 		 * REVISIT: Some wkup sources might not be needed.
 		 */
-		dev->westate = OMAP_I2C_WE_ALL;
+		omap->westate = OMAP_I2C_WE_ALL;
 	}
 
-	if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
+	if (omap->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
 		/*
 		 * The I2C functional clock is the armxor_ck, so there's
 		 * no need to get "armxor_ck" separately.  Now, if OMAP2420
 		 * always returns 12MHz for the functional clock, we can
 		 * do this bit unconditionally.
 		 */
-		fclk = clk_get(dev->dev, "fck");
+		fclk = clk_get(omap->dev, "fck");
 		fclk_rate = clk_get_rate(fclk);
 		clk_put(fclk);
 
···
 			psc = fclk_rate / 12000000;
 	}
 
-	if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
+	if (!(omap->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
 
 		/*
 		 * HSI2C controller internal clk rate should be 19.2 Mhz for
···
 		 * to get longer filter period for better noise suppression.
 		 * The filter is iclk (fclk for HS) period.
 		 */
-		if (dev->speed > 400 ||
-			       dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
+		if (omap->speed > 400 ||
+			       omap->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
 			internal_clk = 19200;
-		else if (dev->speed > 100)
+		else if (omap->speed > 100)
 			internal_clk = 9600;
 		else
 			internal_clk = 4000;
-		fclk = clk_get(dev->dev, "fck");
+		fclk = clk_get(omap->dev, "fck");
 		fclk_rate = clk_get_rate(fclk) / 1000;
 		clk_put(fclk);
 
···
 		psc = psc - 1;
 
 		/* If configured for High Speed */
-		if (dev->speed > 400) {
+		if (omap->speed > 400) {
 			unsigned long scl;
 
 			/* For first phase of HS mode */
···
 			fssclh = (scl / 3) - 5;
 
 			/* For second phase of HS mode */
-			scl = fclk_rate / dev->speed;
+			scl = fclk_rate / omap->speed;
 			hsscll = scl - (scl / 3) - 7;
 			hssclh = (scl / 3) - 5;
-		} else if (dev->speed > 100) {
+		} else if (omap->speed > 100) {
 			unsigned long scl;
 
 			/* Fast mode */
-			scl = internal_clk / dev->speed;
+			scl = internal_clk / omap->speed;
 			fsscll = scl - (scl / 3) - 7;
 			fssclh = (scl / 3) - 5;
 		} else {
 			/* Standard mode */
-			fsscll = internal_clk / (dev->speed * 2) - 7;
-			fssclh = internal_clk / (dev->speed * 2) - 5;
+			fsscll = internal_clk / (omap->speed * 2) - 7;
+			fssclh = internal_clk / (omap->speed * 2) - 5;
 		}
 		scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
 		sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
···
 		fclk_rate /= (psc + 1) * 1000;
 		if (psc > 2)
 			psc = 2;
-		scll = fclk_rate / (dev->speed * 2) - 7 + psc;
-		sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
+		scll = fclk_rate / (omap->speed * 2) - 7 + psc;
+		sclh = fclk_rate / (omap->speed * 2) - 7 + psc;
 	}
 
-	dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
+	omap->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
 			OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
-			OMAP_I2C_IE_AL)  | ((dev->fifo_size) ?
+			OMAP_I2C_IE_AL)  | ((omap->fifo_size) ?
 				(OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
 
-	dev->pscstate = psc;
-	dev->scllstate = scll;
-	dev->sclhstate = sclh;
+	omap->pscstate = psc;
+	omap->scllstate = scll;
+	omap->sclhstate = sclh;
 
-	if (dev->rev <= OMAP_I2C_REV_ON_3430_3530) {
+	if (omap->rev <= OMAP_I2C_REV_ON_3430_3530) {
 		/* Not implemented */
-		dev->bb_valid = 1;
+		omap->bb_valid = 1;
 	}
 
-	__omap_i2c_init(dev);
+	__omap_i2c_init(omap);
 
 	return 0;
 }
···
 /*
  * Waiting on Bus Busy
  */
-static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
+static int omap_i2c_wait_for_bb(struct omap_i2c_dev *omap)
 {
 	unsigned long timeout;
 
 	timeout = jiffies + OMAP_I2C_TIMEOUT;
-	while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
+	while (omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
 		if (time_after(jiffies, timeout))
-			return i2c_recover_bus(&dev->adapter);
+			return i2c_recover_bus(&omap->adapter);
 		msleep(1);
 	}
 
···
  * 3. Any transfer started in the middle of another master's transfer
  *    results in unpredictable results and data corruption
  */
-static int omap_i2c_wait_for_bb_valid(struct omap_i2c_dev *dev)
+static int omap_i2c_wait_for_bb_valid(struct omap_i2c_dev *omap)
 {
 	unsigned long bus_free_timeout = 0;
 	unsigned long timeout;
 	int bus_free = 0;
 	u16 stat, systest;
 
-	if (dev->bb_valid)
+	if (omap->bb_valid)
 		return 0;
 
 	timeout = jiffies + OMAP_I2C_TIMEOUT;
 	while (1) {
-		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+		stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
 		/*
 		 * We will see BB or BF event in a case IP had detected any
 		 * activity on the I2C bus. Now IP correctly tracks the bus
···
 		 * Otherwise, we must look signals on the bus to make
 		 * the right decision.
 		 */
-		systest = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG);
+		systest = omap_i2c_read_reg(omap, OMAP_I2C_SYSTEST_REG);
 		if ((systest & OMAP_I2C_SYSTEST_SCL_I_FUNC) &&
 		    (systest & OMAP_I2C_SYSTEST_SDA_I_FUNC)) {
 			if (!bus_free) {
···
 		}
 
 		if (time_after(jiffies, timeout)) {
-			dev_warn(dev->dev, "timeout waiting for bus ready\n");
+			dev_warn(omap->dev, "timeout waiting for bus ready\n");
 			return -ETIMEDOUT;
 		}
 
 		msleep(1);
 	}
 
-	dev->bb_valid = 1;
+	omap->bb_valid = 1;
 	return 0;
 }
 
-static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx)
+static void omap_i2c_resize_fifo(struct omap_i2c_dev *omap, u8 size, bool is_rx)
 {
 	u16		buf;
 
-	if (dev->flags & OMAP_I2C_FLAG_NO_FIFO)
+	if (omap->flags & OMAP_I2C_FLAG_NO_FIFO)
 		return;
 
 	/*
···
 	 * then we might use draining feature to transfer the remaining bytes.
 	 */
 
-	dev->threshold = clamp(size, (u8) 1, dev->fifo_size);
+	omap->threshold = clamp(size, (u8) 1, omap->fifo_size);
 
-	buf = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
+	buf = omap_i2c_read_reg(omap, OMAP_I2C_BUF_REG);
 
 	if (is_rx) {
 		/* Clear RX Threshold */
 		buf &= ~(0x3f << 8);
-		buf |= ((dev->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR;
+		buf |= ((omap->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR;
 	} else {
 		/* Clear TX Threshold */
 		buf &= ~0x3f;
-		buf |= (dev->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR;
+		buf |= (omap->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR;
 	}
 
-	omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
+	omap_i2c_write_reg(omap, OMAP_I2C_BUF_REG, buf);
 
-	if (dev->rev < OMAP_I2C_REV_ON_3630)
-		dev->b_hw = 1; /* Enable hardware fixes */
+	if (omap->rev < OMAP_I2C_REV_ON_3630)
+		omap->b_hw = 1; /* Enable hardware fixes */
 
 	/* calculate wakeup latency constraint for MPU */
-	if (dev->set_mpu_wkup_lat != NULL)
-		dev->latency = (1000000 * dev->threshold) /
-			(1000 * dev->speed / 8);
+	if (omap->set_mpu_wkup_lat != NULL)
+		omap->latency = (1000000 * omap->threshold) /
+			(1000 * omap->speed / 8);
 }
 
 /*
···
 static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 			     struct i2c_msg *msg, int stop)
 {
-	struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
+	struct omap_i2c_dev *omap = i2c_get_adapdata(adap);
 	unsigned long timeout;
 	u16 w;
 
-	dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
+	dev_dbg(omap->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
 		msg->addr, msg->len, msg->flags, stop);
 
 	if (msg->len == 0)
 		return -EINVAL;
 
-	dev->receiver = !!(msg->flags & I2C_M_RD);
-	omap_i2c_resize_fifo(dev, msg->len, dev->receiver);
+	omap->receiver = !!(msg->flags & I2C_M_RD);
+	omap_i2c_resize_fifo(omap, msg->len, omap->receiver);
 
-	omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
+	omap_i2c_write_reg(omap, OMAP_I2C_SA_REG, msg->addr);
 
 	/* REVISIT: Could the STB bit of I2C_CON be used with probing? */
-	dev->buf = msg->buf;
-	dev->buf_len = msg->len;
+	omap->buf = msg->buf;
+	omap->buf_len = msg->len;
 
-	/* make sure writes to dev->buf_len are ordered */
+	/* make sure writes to omap->buf_len are ordered */
 	barrier();
 
-	omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
+	omap_i2c_write_reg(omap, OMAP_I2C_CNT_REG, omap->buf_len);
 
 	/* Clear the FIFO Buffers */
-	w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
+	w = omap_i2c_read_reg(omap, OMAP_I2C_BUF_REG);
 	w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
-	omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
+	omap_i2c_write_reg(omap, OMAP_I2C_BUF_REG, w);
 
-	reinit_completion(&dev->cmd_complete);
-	dev->cmd_err = 0;
+	reinit_completion(&omap->cmd_complete);
+	omap->cmd_err = 0;
 
 	w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
 
 	/* High speed configuration */
-	if (dev->speed > 400)
+	if (omap->speed > 400)
 		w |= OMAP_I2C_CON_OPMODE_HS;
 
 	if (msg->flags & I2C_M_STOP)
···
 	if (!(msg->flags & I2C_M_RD))
 		w |= OMAP_I2C_CON_TRX;
 
-	if (!dev->b_hw && stop)
+	if (!omap->b_hw && stop)
 		w |= OMAP_I2C_CON_STP;
 	/*
 	 * NOTE: STAT_BB bit could became 1 here if another master occupy
 	 * the bus. IP successfully complete transfer when the bus will be
 	 * free again (BB reset to 0).
 	 */
-	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
+	omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, w);
 
 	/*
 	 * Don't write stt and stp together on some hardware.
 	 */
-	if (dev->b_hw && stop) {
+	if (omap->b_hw && stop) {
 		unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
-		u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
+		u16 con = omap_i2c_read_reg(omap, OMAP_I2C_CON_REG);
 		while (con & OMAP_I2C_CON_STT) {
-			con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
+			con = omap_i2c_read_reg(omap, OMAP_I2C_CON_REG);
 
 			/* Let the user know if i2c is in a bad state */
 			if (time_after(jiffies, delay)) {
-				dev_err(dev->dev, "controller timed out "
+				dev_err(omap->dev, "controller timed out "
 				"waiting for start condition to finish\n");
 				return -ETIMEDOUT;
 			}
···
 
 		w |= OMAP_I2C_CON_STP;
 		w &= ~OMAP_I2C_CON_STT;
-		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
+		omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, w);
 	}
 
 	/*
 	 * REVISIT: We should abort the transfer on signals, but the bus goes
 	 * into arbitration and we're currently unable to recover from it.
 	 */
-	timeout = wait_for_completion_timeout(&dev->cmd_complete,
+	timeout = wait_for_completion_timeout(&omap->cmd_complete,
 						OMAP_I2C_TIMEOUT);
 	if (timeout == 0) {
-		dev_err(dev->dev, "controller timed out\n");
-		omap_i2c_reset(dev);
-		__omap_i2c_init(dev);
+		dev_err(omap->dev, "controller timed out\n");
+		omap_i2c_reset(omap);
+		__omap_i2c_init(omap);
 		return -ETIMEDOUT;
 	}
 
-	if (likely(!dev->cmd_err))
+	if (likely(!omap->cmd_err))
 		return 0;
 
 	/* We have an error */
-	if (dev->cmd_err & (OMAP_I2C_STAT_ROVR | OMAP_I2C_STAT_XUDF)) {
-		omap_i2c_reset(dev);
-		__omap_i2c_init(dev);
+	if (omap->cmd_err & (OMAP_I2C_STAT_ROVR | OMAP_I2C_STAT_XUDF)) {
+		omap_i2c_reset(omap);
+		__omap_i2c_init(omap);
 		return -EIO;
 	}
 
-	if (dev->cmd_err & OMAP_I2C_STAT_AL)
+	if (omap->cmd_err & OMAP_I2C_STAT_AL)
 		return -EAGAIN;
 
-	if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
+	if (omap->cmd_err & OMAP_I2C_STAT_NACK) {
 		if (msg->flags & I2C_M_IGNORE_NAK)
 			return 0;
 
-		w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
+		w = omap_i2c_read_reg(omap, OMAP_I2C_CON_REG);
 		w |= OMAP_I2C_CON_STP;
-		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
+		omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, w);
 		return -EREMOTEIO;
 	}
 	return -EIO;
···
 static int
 omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 {
-	struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
+	struct omap_i2c_dev *omap = i2c_get_adapdata(adap);
 	int i;
 	int r;
 
-	r = pm_runtime_get_sync(dev->dev);
+	r = pm_runtime_get_sync(omap->dev);
 	if (r < 0)
 		goto out;
 
-	r = omap_i2c_wait_for_bb_valid(dev);
+	r = omap_i2c_wait_for_bb_valid(omap);
 	if (r < 0)
 		goto out;
 
-	r = omap_i2c_wait_for_bb(dev);
+	r = omap_i2c_wait_for_bb(omap);
 	if (r < 0)
 		goto out;
 
-	if (dev->set_mpu_wkup_lat != NULL)
-		dev->set_mpu_wkup_lat(dev->dev, dev->latency);
+	if (omap->set_mpu_wkup_lat != NULL)
+		omap->set_mpu_wkup_lat(omap->dev, omap->latency);
 
 	for (i = 0; i < num; i++) {
 		r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
···
 	if (r == 0)
 		r = num;
 
-	omap_i2c_wait_for_bb(dev);
+	omap_i2c_wait_for_bb(omap);
 
-	if (dev->set_mpu_wkup_lat != NULL)
-		dev->set_mpu_wkup_lat(dev->dev, -1);
+	if (omap->set_mpu_wkup_lat != NULL)
+		omap->set_mpu_wkup_lat(omap->dev, -1);
 
 out:
-	pm_runtime_mark_last_busy(dev->dev);
-	pm_runtime_put_autosuspend(dev->dev);
+	pm_runtime_mark_last_busy(omap->dev);
+	pm_runtime_put_autosuspend(omap->dev);
 	return r;
 }
 
···
 }
 
 static inline void
-omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
+omap_i2c_complete_cmd(struct omap_i2c_dev *omap, u16 err)
 {
-	dev->cmd_err |= err;
-	complete(&dev->cmd_complete);
+	omap->cmd_err |= err;
+	complete(&omap->cmd_complete);
 }
 
 static inline void
-omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
+omap_i2c_ack_stat(struct omap_i2c_dev *omap, u16 stat)
 {
-	omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
+	omap_i2c_write_reg(omap, OMAP_I2C_STAT_REG, stat);
 }
 
-static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
+static inline void i2c_omap_errata_i207(struct omap_i2c_dev *omap, u16 stat)
 {
 	/*
 	 * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
···
 	 */
 	if (stat & OMAP_I2C_STAT_RDR) {
 		/* Step 1: If RDR is set, clear it */
-		omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
+		omap_i2c_ack_stat(omap, OMAP_I2C_STAT_RDR);
 
 		/* Step 2: */
-		if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
+		if (!(omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG)
 						& OMAP_I2C_STAT_BB)) {
 
 			/* Step 3: */
-			if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
+			if (omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG)
 						& OMAP_I2C_STAT_RDR) {
-				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
-				dev_dbg(dev->dev, "RDR when bus is busy.\n");
+				omap_i2c_ack_stat(omap, OMAP_I2C_STAT_RDR);
+				dev_dbg(omap->dev, "RDR when bus is busy.\n");
 			}
 
 		}
···
 static irqreturn_t
 omap_i2c_omap1_isr(int this_irq, void *dev_id)
 {
-	struct omap_i2c_dev *dev = dev_id;
+	struct omap_i2c_dev *omap = dev_id;
 	u16 iv, w;
 
-	if (pm_runtime_suspended(dev->dev))
+	if (pm_runtime_suspended(omap->dev))
 		return IRQ_NONE;
 
-	iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
+	iv = omap_i2c_read_reg(omap, OMAP_I2C_IV_REG);
 	switch (iv) {
 	case 0x00:	/* None */
 		break;
 	case 0x01:	/* Arbitration lost */
-		dev_err(dev->dev, "Arbitration lost\n");
-		omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
+		dev_err(omap->dev, "Arbitration lost\n");
+		omap_i2c_complete_cmd(omap, OMAP_I2C_STAT_AL);
 		break;
 	case 0x02:	/* No acknowledgement */
-		omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
-		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
+		omap_i2c_complete_cmd(omap, OMAP_I2C_STAT_NACK);
+		omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
 		break;
 	case 0x03:	/* Register access ready */
-		omap_i2c_complete_cmd(dev, 0);
+		omap_i2c_complete_cmd(omap, 0);
 		break;
 	case 0x04:	/* Receive data ready */
-		if (dev->buf_len) {
-			w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
-			*dev->buf++ = w;
-			dev->buf_len--;
-			if (dev->buf_len) {
-				*dev->buf++ = w >> 8;
-				dev->buf_len--;
+		if (omap->buf_len) {
+			w = omap_i2c_read_reg(omap, OMAP_I2C_DATA_REG);
+			*omap->buf++ = w;
+			omap->buf_len--;
+			if (omap->buf_len) {
+				*omap->buf++ = w >> 8;
+				omap->buf_len--;
 			}
 		} else
-			dev_err(dev->dev, "RRDY IRQ while no data requested\n");
+			dev_err(omap->dev, "RRDY IRQ while no data requested\n");
 		break;
 	case 0x05:	/* Transmit data ready */
-		if (dev->buf_len) {
-			w = *dev->buf++;
-			dev->buf_len--;
-			if (dev->buf_len) {
-				w |= *dev->buf++ << 8;
-				dev->buf_len--;
+		if (omap->buf_len) {
+			w = *omap->buf++;
+			omap->buf_len--;
+			if (omap->buf_len) {
+				w |= *omap->buf++ << 8;
+				omap->buf_len--;
 			}
-			omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
+			omap_i2c_write_reg(omap, OMAP_I2C_DATA_REG, w);
 		} else
-			dev_err(dev->dev, "XRDY IRQ while no data to send\n");
+			dev_err(omap->dev, "XRDY IRQ while no data to send\n");
 		break;
 	default:
 		return IRQ_NONE;
···
  * data to DATA_REG. Otherwise some data bytes can be lost while transferring
  * them from the memory to the I2C interface.
  */
-static int errata_omap3_i462(struct omap_i2c_dev *dev)
+static int errata_omap3_i462(struct omap_i2c_dev *omap)
 {
 	unsigned long timeout = 10000;
 	u16 stat;
 
 	do {
-		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+		stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
 		if (stat & OMAP_I2C_STAT_XUDF)
 			break;
 
 		if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
-			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
+			omap_i2c_ack_stat(omap, (OMAP_I2C_STAT_XRDY |
 							OMAP_I2C_STAT_XDR));
 			if (stat & OMAP_I2C_STAT_NACK) {
-				dev->cmd_err |= OMAP_I2C_STAT_NACK;
-				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
+				omap->cmd_err |= OMAP_I2C_STAT_NACK;
+				omap_i2c_ack_stat(omap, OMAP_I2C_STAT_NACK);
 			}
 
 			if (stat & OMAP_I2C_STAT_AL) {
-				dev_err(dev->dev, "Arbitration lost\n");
-				dev->cmd_err |= OMAP_I2C_STAT_AL;
-				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
+				dev_err(omap->dev, "Arbitration lost\n");
+				omap->cmd_err |= OMAP_I2C_STAT_AL;
+				omap_i2c_ack_stat(omap, OMAP_I2C_STAT_AL);
 			}
 
 			return -EIO;
···
 	} while (--timeout);
 
 	if (!timeout) {
-		dev_err(dev->dev, "timeout waiting on XUDF bit\n");
+		dev_err(omap->dev, "timeout waiting on XUDF bit\n");
 		return 0;
 	}
 
 	return 0;
 }
 
-static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
+static void omap_i2c_receive_data(struct omap_i2c_dev *omap, u8 num_bytes,
 		bool is_rdr)
 {
 	u16		w;
 
 	while (num_bytes--) {
-		w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
-		*dev->buf++ = w;
-		dev->buf_len--;
+		w = omap_i2c_read_reg(omap, OMAP_I2C_DATA_REG);
+		*omap->buf++ = w;
+		omap->buf_len--;
 
 		/*
 		 * Data reg in 2430, omap3 and
 		 * omap4 is 8 bit wide
 		 */
-		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
-			*dev->buf++ = w >> 8;
-			dev->buf_len--;
+		if (omap->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
+			*omap->buf++ = w >> 8;
+			omap->buf_len--;
 		}
 	}
 }
 
-static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
+static int omap_i2c_transmit_data(struct omap_i2c_dev *omap, u8 num_bytes,
 		bool is_xdr)
 {
 	u16		w;
 
 	while (num_bytes--) {
-		w = *dev->buf++;
-		dev->buf_len--;
+		w = *omap->buf++;
+		omap->buf_len--;
 
 		/*
 		 * Data reg in 2430, omap3 and
 		 * omap4 is 8 bit wide
 		 */
-		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
-			w |= *dev->buf++ << 8;
-			dev->buf_len--;
+		if (omap->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
+			w |= *omap->buf++ << 8;
+			omap->buf_len--;
 		}
 
-		if (dev->errata & I2C_OMAP_ERRATA_I462) {
+		if (omap->errata & I2C_OMAP_ERRATA_I462) {
 			int ret;
 
-			ret = errata_omap3_i462(dev);
+			ret = errata_omap3_i462(omap);
 			if (ret < 0)
 				return ret;
 		}
 
-		omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
+		omap_i2c_write_reg(omap, OMAP_I2C_DATA_REG, w);
 	}
 
 	return 0;
···
 static irqreturn_t
 omap_i2c_isr(int irq, void *dev_id)
 {
-	struct omap_i2c_dev *dev = dev_id;
+	struct omap_i2c_dev *omap = dev_id;
 	irqreturn_t ret = IRQ_HANDLED;
 	u16 mask;
 	u16 stat;
 
-	spin_lock(&dev->lock);
-	mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
-	stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+	spin_lock(&omap->lock);
+	mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
+	stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
 
 	if (stat & mask)
 		ret = IRQ_WAKE_THREAD;
 
-	spin_unlock(&dev->lock);
+	spin_unlock(&omap->lock);
 
 	return ret;
 }
···
 static irqreturn_t
 omap_i2c_isr_thread(int this_irq, void *dev_id)
 {
-	struct omap_i2c_dev *dev = dev_id;
+	struct omap_i2c_dev *omap = dev_id;
 	unsigned long flags;
 	u16 bits;
 	u16 stat;
 	int err = 0, count = 0;
 
-	spin_lock_irqsave(&dev->lock, flags);
+	spin_lock_irqsave(&omap->lock, flags);
 	do {
-		bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
-		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+		bits = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
+		stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
 		stat &= bits;
 
 		/* If we're in receiver mode, ignore XDR/XRDY */
-		if (dev->receiver)
+		if (omap->receiver)
 			stat &= ~(OMAP_I2C_STAT_XDR | OMAP_I2C_STAT_XRDY);
 		else
 			stat &= ~(OMAP_I2C_STAT_RDR | OMAP_I2C_STAT_RRDY);
···
 			goto out;
 		}
 
-		dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
+		dev_dbg(omap->dev, "IRQ (ISR = 0x%04x)\n", stat);
 		if (count++ == 100) {
-			dev_warn(dev->dev, "Too much work in one IRQ\n");
+			dev_warn(omap->dev, "Too much work in one IRQ\n");
 			break;
 		}
 
 		if (stat & OMAP_I2C_STAT_NACK) {
 			err |= OMAP_I2C_STAT_NACK;
-			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
+			omap_i2c_ack_stat(omap, OMAP_I2C_STAT_NACK);
 		}
 
 		if (stat & OMAP_I2C_STAT_AL) {
-			dev_err(dev->dev, "Arbitration lost\n");
+			dev_err(omap->dev, "Arbitration lost\n");
 			err |= OMAP_I2C_STAT_AL;
-			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
+			omap_i2c_ack_stat(omap, OMAP_I2C_STAT_AL);
 		}
 
 		/*
 		 * ProDB0017052: Clear ARDY bit twice
 		 */
 		if (stat & OMAP_I2C_STAT_ARDY)
-			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ARDY);
+			omap_i2c_ack_stat(omap, OMAP_I2C_STAT_ARDY);
 
 		if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
 					OMAP_I2C_STAT_AL)) {
-			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
+			omap_i2c_ack_stat(omap, (OMAP_I2C_STAT_RRDY |
 						OMAP_I2C_STAT_RDR |
 						OMAP_I2C_STAT_XRDY |
 						OMAP_I2C_STAT_XDR |
···
 		if (stat & OMAP_I2C_STAT_RDR) {
 			u8 num_bytes = 1;
 
-			if (dev->fifo_size)
-				num_bytes = dev->buf_len;
+			if (omap->fifo_size)
+				num_bytes = omap->buf_len;
 
-			if (dev->errata & I2C_OMAP_ERRATA_I207) {
-				i2c_omap_errata_i207(dev, stat);
-				num_bytes = (omap_i2c_read_reg(dev,
+			if (omap->errata & I2C_OMAP_ERRATA_I207) {
+				i2c_omap_errata_i207(omap, stat);
+				num_bytes = (omap_i2c_read_reg(omap,
 					OMAP_I2C_BUFSTAT_REG) >> 8) & 0x3F;
 			}
 
-			omap_i2c_receive_data(dev, num_bytes, true);
-			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
+			omap_i2c_receive_data(omap, num_bytes, true);
+			omap_i2c_ack_stat(omap, OMAP_I2C_STAT_RDR);
 			continue;
 		}
 
 		if (stat & OMAP_I2C_STAT_RRDY) {
 			u8 num_bytes = 1;
 
-			if (dev->threshold)
-				num_bytes = dev->threshold;
+			if (omap->threshold)
+				num_bytes = omap->threshold;
 
-			omap_i2c_receive_data(dev, num_bytes, false);
-			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
+			omap_i2c_receive_data(omap, num_bytes, false);
+			omap_i2c_ack_stat(omap, OMAP_I2C_STAT_RRDY);
 			continue;
 		}
 
···
 			u8 num_bytes = 1;
 			int ret;
 
-			if (dev->fifo_size)
-				num_bytes = dev->buf_len;
+			if (omap->fifo_size)
+				num_bytes = omap->buf_len;
 
-			ret = omap_i2c_transmit_data(dev, num_bytes, true);
+			ret = omap_i2c_transmit_data(omap, num_bytes, true);
 			if (ret < 0)
 				break;
 
-			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
+			omap_i2c_ack_stat(omap, OMAP_I2C_STAT_XDR);
 			continue;
 		}
 
···
 			u8 num_bytes = 1;
 			int ret;
 
-			if (dev->threshold)
-				num_bytes = dev->threshold;
+			if (omap->threshold)
+				num_bytes = omap->threshold;
 
-			ret = omap_i2c_transmit_data(dev, num_bytes, false);
+			ret = omap_i2c_transmit_data(omap, num_bytes, false);
 			if (ret < 0)
 				break;
 
-			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
+			omap_i2c_ack_stat(omap, OMAP_I2C_STAT_XRDY);
 			continue;
 		}
 
 		if (stat & OMAP_I2C_STAT_ROVR) {
-			dev_err(dev->dev, "Receive overrun\n");
+			dev_err(omap->dev, "Receive overrun\n");
 			err |= OMAP_I2C_STAT_ROVR;
-			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR);
+			omap_i2c_ack_stat(omap, OMAP_I2C_STAT_ROVR);
 			break;
 		}
 
 		if (stat & OMAP_I2C_STAT_XUDF) {
-			dev_err(dev->dev, "Transmit underflow\n");
+			dev_err(omap->dev, "Transmit underflow\n");
 			err |= OMAP_I2C_STAT_XUDF;
-			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF);
+			omap_i2c_ack_stat(omap, OMAP_I2C_STAT_XUDF);
 			break;
 		}
 	} while (stat);
 
-	omap_i2c_complete_cmd(dev, err);
+	omap_i2c_complete_cmd(omap, err);
 
 out:
-	spin_unlock_irqrestore(&dev->lock, flags);
+	spin_unlock_irqrestore(&omap->lock, flags);
 
 	return IRQ_HANDLED;
 }
···
 static int
 omap_i2c_probe(struct platform_device *pdev)
 {
-	struct omap_i2c_dev	*dev;
+	struct omap_i2c_dev	*omap;
 	struct i2c_adapter	*adap;
 	struct resource		*mem;
 	const struct omap_i2c_bus_platform_data *pdata =
···
 		return irq;
 	}
 
-	dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
-	if (!dev)
+	omap = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
+	if (!omap)
 		return -ENOMEM;
 
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	dev->base = devm_ioremap_resource(&pdev->dev, mem);
-	if (IS_ERR(dev->base))
-		return PTR_ERR(dev->base);
+	omap->base = devm_ioremap_resource(&pdev->dev, mem);
+	if (IS_ERR(omap->base))
+		return PTR_ERR(omap->base);
 
 	match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
 	if (match) {
 		u32 freq = 100000; /* default to 100000 Hz */
 
 		pdata = match->data;
-		dev->flags = pdata->flags;
+		omap->flags = pdata->flags;
 
 		of_property_read_u32(node, "clock-frequency", &freq);
 		/* convert DT freq value in Hz into kHz for speed */
-		dev->speed = freq / 1000;
+		omap->speed = freq / 1000;
 	} else if (pdata != NULL) {
-		dev->speed = pdata->clkrate;
-		dev->flags = pdata->flags;
-		dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
+		omap->speed = pdata->clkrate;
+		omap->flags = pdata->flags;
+		omap->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
 	}
 
-	dev->dev = &pdev->dev;
-	dev->irq = irq;
+	omap->dev = &pdev->dev;
+	omap->irq = irq;
 
-	spin_lock_init(&dev->lock);
+	spin_lock_init(&omap->lock);
 
-	platform_set_drvdata(pdev, dev);
-	init_completion(&dev->cmd_complete);
+	platform_set_drvdata(pdev, omap);
+	init_completion(&omap->cmd_complete);
 
-	dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
+	omap->reg_shift = (omap->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
 
-	pm_runtime_enable(dev->dev);
-	pm_runtime_set_autosuspend_delay(dev->dev, OMAP_I2C_PM_TIMEOUT);
-	pm_runtime_use_autosuspend(dev->dev);
+	pm_runtime_enable(omap->dev);
+	pm_runtime_set_autosuspend_delay(omap->dev, OMAP_I2C_PM_TIMEOUT);
+	pm_runtime_use_autosuspend(omap->dev);
 
-	r = pm_runtime_get_sync(dev->dev);
+	r = pm_runtime_get_sync(omap->dev);
 	if (r < 0)
 		goto err_free_mem;
 
···
 	 * Also since the omap_i2c_read_reg uses reg_map_ip_* a
 	 * readw_relaxed is done.
 	 */
-	rev = readw_relaxed(dev->base + 0x04);
+	rev = readw_relaxed(omap->base + 0x04);
 
-	dev->scheme = OMAP_I2C_SCHEME(rev);
-	switch (dev->scheme) {
+	omap->scheme = OMAP_I2C_SCHEME(rev);
+	switch (omap->scheme) {
 	case OMAP_I2C_SCHEME_0:
-		dev->regs = (u8 *)reg_map_ip_v1;
-		dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG);
-		minor = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
-		major = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
+		omap->regs = (u8 *)reg_map_ip_v1;
+		omap->rev = omap_i2c_read_reg(omap, OMAP_I2C_REV_REG);
+		minor = OMAP_I2C_REV_SCHEME_0_MAJOR(omap->rev);
+		major = OMAP_I2C_REV_SCHEME_0_MAJOR(omap->rev);
 		break;
 	case OMAP_I2C_SCHEME_1:
 		/* FALLTHROUGH */
 	default:
-		dev->regs = (u8 *)reg_map_ip_v2;
+		omap->regs = (u8 *)reg_map_ip_v2;
 		rev = (rev << 16) |
-			omap_i2c_read_reg(dev, OMAP_I2C_IP_V2_REVNB_LO);
+			omap_i2c_read_reg(omap, OMAP_I2C_IP_V2_REVNB_LO);
 		minor = OMAP_I2C_REV_SCHEME_1_MINOR(rev);
 		major = OMAP_I2C_REV_SCHEME_1_MAJOR(rev);
-		dev->rev = rev;
+		omap->rev = rev;
 	}
 
-	dev->errata = 0;
+	omap->errata = 0;
 
-	if (dev->rev >= OMAP_I2C_REV_ON_2430 &&
-			dev->rev < OMAP_I2C_REV_ON_4430_PLUS)
-		dev->errata |= I2C_OMAP_ERRATA_I207;
+	if (omap->rev >= OMAP_I2C_REV_ON_2430 &&
+			omap->rev < OMAP_I2C_REV_ON_4430_PLUS)
+		omap->errata |= I2C_OMAP_ERRATA_I207;
 
-	if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
-		dev->errata |= I2C_OMAP_ERRATA_I462;
+	if (omap->rev <= OMAP_I2C_REV_ON_3430_3530)
+		omap->errata |= I2C_OMAP_ERRATA_I462;
 
-	if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
+	if (!(omap->flags & OMAP_I2C_FLAG_NO_FIFO)) {
 		u16 s;
 
 		/* Set up the fifo size - Get total size */
-		s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
-		dev->fifo_size = 0x8 << s;
+		s = (omap_i2c_read_reg(omap, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
+		omap->fifo_size = 0x8 << s;
 
 		/*
 		 * Set up notification threshold as half the total available
···
 		 * call back latencies.
 		 */
 
-		dev->fifo_size = (dev->fifo_size / 2);
+		omap->fifo_size = (omap->fifo_size / 2);
 
-		if (dev->rev < OMAP_I2C_REV_ON_3630)
-			dev->b_hw = 1; /* Enable hardware fixes */
+		if (omap->rev < OMAP_I2C_REV_ON_3630)
+			omap->b_hw = 1; /* Enable hardware fixes */
 
 		/* calculate wakeup latency constraint for MPU */
-		if (dev->set_mpu_wkup_lat != NULL)
-			dev->latency = (1000000 * dev->fifo_size) /
-				       (1000 * dev->speed / 8);
+		if (omap->set_mpu_wkup_lat != NULL)
+			omap->latency = (1000000 * omap->fifo_size) /
+				       (1000 * omap->speed / 8);
 	}
 
 	/* reset ASAP, clearing any IRQs */
-	omap_i2c_init(dev);
+	omap_i2c_init(omap);
 
-	if (dev->rev < OMAP_I2C_OMAP1_REV_2)
-		r = devm_request_irq(&pdev->dev, dev->irq, omap_i2c_omap1_isr,
-				IRQF_NO_SUSPEND, pdev->name, dev);
+	if (omap->rev < OMAP_I2C_OMAP1_REV_2)
+		r = devm_request_irq(&pdev->dev, omap->irq, omap_i2c_omap1_isr,
+				IRQF_NO_SUSPEND, pdev->name, omap);
 	else
-		r = devm_request_threaded_irq(&pdev->dev, dev->irq,
+		r = devm_request_threaded_irq(&pdev->dev, omap->irq,
 				omap_i2c_isr, omap_i2c_isr_thread,
 				IRQF_NO_SUSPEND | IRQF_ONESHOT,
-				pdev->name, dev);
+				pdev->name, omap);
 
 	if (r) {
-		dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
+		dev_err(omap->dev, "failure requesting irq %i\n", omap->irq);
 		goto err_unuse_clocks;
 	}
 
-	adap = &dev->adapter;
-	i2c_set_adapdata(adap, dev);
+	adap = &omap->adapter;
+	i2c_set_adapdata(adap, omap);
 	adap->owner = THIS_MODULE;
 	adap->class = I2C_CLASS_DEPRECATED;
 	strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
···
 	adap->nr = pdev->id;
 	r = i2c_add_numbered_adapter(adap);
 	if (r) {
-		dev_err(dev->dev, "failure adding adapter\n");
+		dev_err(omap->dev, "failure adding adapter\n");
 		goto err_unuse_clocks;
 	}
 
-	dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr,
-		 major, minor, dev->speed);
+	dev_info(omap->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr,
+		 major, minor, omap->speed);
 
-	pm_runtime_mark_last_busy(dev->dev);
-	pm_runtime_put_autosuspend(dev->dev);
+	pm_runtime_mark_last_busy(omap->dev);
+	pm_runtime_put_autosuspend(omap->dev);
 
 	return 0;
 
 err_unuse_clocks:
-	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
-	pm_runtime_put(dev->dev);
+	omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0);
+	pm_runtime_put(omap->dev);
 	pm_runtime_disable(&pdev->dev);
 err_free_mem:
 
···
 
 static int omap_i2c_remove(struct platform_device *pdev)
 {
-	struct omap_i2c_dev	*dev = platform_get_drvdata(pdev);
+	struct omap_i2c_dev	*omap = platform_get_drvdata(pdev);
 	int ret;
 
-	i2c_del_adapter(&dev->adapter);
+	i2c_del_adapter(&omap->adapter);
 	ret = pm_runtime_get_sync(&pdev->dev);
 	if (ret < 0)
 		return ret;
 
-	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
-	pm_runtime_put(&pdev->dev);
+	omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0);
+	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	return 0;
 }
···
 #ifdef CONFIG_PM
 static int omap_i2c_runtime_suspend(struct device *dev)
 {
-	struct platform_device *pdev = to_platform_device(dev);
-	struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
+	struct omap_i2c_dev *omap = dev_get_drvdata(dev);
 
-	_dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
+	omap->iestate = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
 
-	if (_dev->scheme == OMAP_I2C_SCHEME_0)
-		omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
+	if (omap->scheme == OMAP_I2C_SCHEME_0)
+		omap_i2c_write_reg(omap, OMAP_I2C_IE_REG, 0);
 	else
-		omap_i2c_write_reg(_dev, OMAP_I2C_IP_V2_IRQENABLE_CLR,
+		omap_i2c_write_reg(omap, OMAP_I2C_IP_V2_IRQENABLE_CLR,
 				   OMAP_I2C_IP_V2_INTERRUPTS_MASK);
 
-	if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
-		omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
+	if (omap->rev < OMAP_I2C_OMAP1_REV_2) {
+		omap_i2c_read_reg(omap, OMAP_I2C_IV_REG); /* Read clears */
 	} else {
-		omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
+		omap_i2c_write_reg(omap, OMAP_I2C_STAT_REG, omap->iestate);
 
 		/* Flush posted write */
-		omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG);
+		omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
 	}
 
 	pinctrl_pm_select_sleep_state(dev);
···
 
 static int omap_i2c_runtime_resume(struct device *dev)
 {
-	struct platform_device *pdev = to_platform_device(dev);
-	struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
+	struct omap_i2c_dev *omap = dev_get_drvdata(dev);
 
 	pinctrl_pm_select_default_state(dev);
 
-	if (!_dev->regs)
+	if (!omap->regs)
 		return 0;
 
-	__omap_i2c_init(_dev);
+	__omap_i2c_init(omap);
 
 	return 0;
 }

drivers/i2c/busses/i2c-parport.c

···
    GNU General Public License for more details.
  * ------------------------------------------------------------------------ */
 
+#define pr_fmt(fmt) "i2c-parport: " fmt
+
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
···
 			break;
 	}
 	if (i == MAX_DEVICE) {
-		pr_debug("i2c-parport: Not using parport%d.\n", port->number);
+		pr_debug("Not using parport%d.\n", port->number);
 		return;
 	}
 
 	adapter = kzalloc(sizeof(struct i2c_par), GFP_KERNEL);
-	if (adapter == NULL) {
-		printk(KERN_ERR "i2c-parport: Failed to kzalloc\n");
+	if (!adapter)
 		return;
-	}
 	memset(&i2c_parport_cb, 0, sizeof(i2c_parport_cb));
 	i2c_parport_cb.flags = PARPORT_FLAG_EXCL;
 	i2c_parport_cb.irq_func = i2c_parport_irq;
 	i2c_parport_cb.private = adapter;
 
-	pr_debug("i2c-parport: attaching to %s\n", port->name);
+	pr_debug("attaching to %s\n", port->name);
 	parport_disable_irq(port);
 	adapter->pdev = parport_register_dev_model(port, "i2c-parport",
 						   &i2c_parport_cb, i);
 	if (!adapter->pdev) {
-		printk(KERN_ERR "i2c-parport: Unable to register with parport\n");
+		pr_err("Unable to register with parport\n");
 		goto err_free;
 	}
 
···
 	adapter->adapter.dev.parent = port->physport->dev;
 
 	if (parport_claim_or_block(adapter->pdev) < 0) {
-		printk(KERN_ERR "i2c-parport: Could not claim parallel port\n");
+		dev_err(&adapter->pdev->dev,
+			"Could not claim parallel port\n");
 		goto err_unregister;
 	}
 
···
 	}
 
 	if (i2c_bit_add_bus(&adapter->adapter) < 0) {
-		printk(KERN_ERR "i2c-parport: Unable to register with I2C\n");
+		dev_err(&adapter->pdev->dev, "Unable to register with I2C\n");
 		goto err_unregister;
 	}
 
···
 		if (adapter->ara)
 			parport_enable_irq(port);
 		else
-			printk(KERN_WARNING "i2c-parport: Failed to register "
-			       "ARA client\n");
+			dev_warn(&adapter->pdev->dev,
+				 "Failed to register ARA client\n");
 	}
 
 	/* Add the new adapter to the list */
···
 static int __init i2c_parport_init(void)
 {
 	if (type < 0) {
-		printk(KERN_WARNING "i2c-parport: adapter type unspecified\n");
+		pr_warn("adapter type unspecified\n");
 		return -ENODEV;
 	}
 
 	if (type >= ARRAY_SIZE(adapter_parm)) {
-		printk(KERN_WARNING "i2c-parport: invalid type (%d)\n", type);
+		pr_warn("invalid type (%d)\n", type);
 		return -ENODEV;
 	}
 

drivers/i2c/busses/i2c-parport.h

···
 		.getsda	= { 0x80, PORT_STAT, 1 },
 		.init	= { 0x04, PORT_DATA, 1 },
 	},
+	/* type 8: VCT-jig */
+	{
+		.setsda	= { 0x04, PORT_DATA, 1 },
+		.setscl	= { 0x01, PORT_DATA, 1 },
+		.getsda	= { 0x40, PORT_STAT, 0 },
+		.getscl	= { 0x80, PORT_STAT, 1 },
+	},
 };
 
 static int type = -1;
···
 	" 5 = ADM1025, ADM1030 and ADM1031 evaluation boards\n"
 	" 6 = Barco LPT->DVI (K5800236) adapter\n"
 	" 7 = One For All JP1 parallel port adapter\n"
+	" 8 = VCT-jig\n"
 );

drivers/i2c/busses/i2c-pxa.c

···
 	unsigned int		msg_idx;
 	unsigned int		msg_ptr;
 	unsigned int		slave_addr;
+	unsigned int		req_slave_addr;
 
 	struct i2c_adapter	adap;
 	struct clk		*clk;
···
 static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why)
 {
 	unsigned int i;
-	printk(KERN_ERR "i2c: error: %s\n", why);
-	printk(KERN_ERR "i2c: msg_num: %d msg_idx: %d msg_ptr: %d\n",
+	struct device *dev = &i2c->adap.dev;
+
+	dev_err(dev, "slave_0x%x error: %s\n",
+		i2c->req_slave_addr >> 1, why);
+	dev_err(dev, "msg_num: %d msg_idx: %d msg_ptr: %d\n",
 		i2c->msg_num, i2c->msg_idx, i2c->msg_ptr);
-	printk(KERN_ERR "i2c: ICR: %08x ISR: %08x\n",
-	       readl(_ICR(i2c)), readl(_ISR(i2c)));
-	printk(KERN_DEBUG "i2c: log: ");
+	dev_err(dev, "IBMR: %08x IDBR: %08x ICR: %08x ISR: %08x\n",
+		readl(_IBMR(i2c)), readl(_IDBR(i2c)), readl(_ICR(i2c)),
+		readl(_ISR(i2c)));
+	dev_dbg(dev, "log: ");
 	for (i = 0; i < i2c->irqlogidx; i++)
-		printk("[%08x:%08x] ", i2c->isrlog[i], i2c->icrlog[i]);
-	printk("\n");
+		pr_debug("[%08x:%08x] ", i2c->isrlog[i], i2c->icrlog[i]);
+
+	pr_debug("\n");
 }
 
 #else /* ifdef DEBUG */
···
 	writel(I2C_ISR_INIT, _ISR(i2c));
 	writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c));
 
-	if (i2c->reg_isar)
+	if (i2c->reg_isar && IS_ENABLED(CONFIG_I2C_PXA_SLAVE))
 		writel(i2c->slave_addr, _ISAR(i2c));
 
 	/* set control register values */
···
 	 * Step 1: target slave address into IDBR
 	 */
 	writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
+	i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
 
 	/*
 	 * Step 2: initiate the write.
···
 	ret = i2c->msg_idx;
 
 out:
-	if (timeout == 0)
+	if (timeout == 0) {
 		i2c_pxa_scream_blue_murder(i2c, "timeout");
+		ret = I2C_RETRY;
+	}
 
 	return ret;
 }
···
 		 * Write the next address.
 		 */
 		writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
+		i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
 
 		/*
 		 * And trigger a repeated start, and send the byte.
···
 		i2c->use_pio = 1;
 	if (of_get_property(np, "mrvl,i2c-fast-mode", NULL))
 		i2c->fast_mode = 1;
-	*i2c_types = (u32)(of_id->data);
+
+	*i2c_types = (enum pxa_i2c_types)(of_id->data);
+
 	return 0;
 }
 
···
 	struct resource *res = NULL;
 	int ret, irq;
 
-	i2c = kzalloc(sizeof(struct pxa_i2c), GFP_KERNEL);
-	if (!i2c) {
-		ret = -ENOMEM;
-		goto emalloc;
+	i2c = devm_kzalloc(&dev->dev, sizeof(struct pxa_i2c), GFP_KERNEL);
+	if (!i2c)
+		return -ENOMEM;
+
+	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+	i2c->reg_base = devm_ioremap_resource(&dev->dev, res);
+	if (IS_ERR(i2c->reg_base))
+		return PTR_ERR(i2c->reg_base);
+
+	irq = platform_get_irq(dev, 0);
+	if (irq < 0) {
+		dev_err(&dev->dev, "no irq resource: %d\n", irq);
+		return irq;
 	}
 
 	/* Default adapter num to device id; i2c_pxa_probe_dt can override. */
···
 	if (ret > 0)
 		ret = i2c_pxa_probe_pdata(dev, i2c, &i2c_type);
 	if (ret < 0)
-		goto eclk;
-
-	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
-	irq = platform_get_irq(dev, 0);
-	if (res == NULL || irq < 0) {
-		ret = -ENODEV;
-		goto eclk;
-	}
-
-	if (!request_mem_region(res->start, resource_size(res), res->name)) {
-		ret = -ENOMEM;
-		goto eclk;
-	}
+		return ret;
 
 	i2c->adap.owner   = THIS_MODULE;
 	i2c->adap.retries = 5;
···
 
 	strlcpy(i2c->adap.name, "pxa_i2c-i2c", sizeof(i2c->adap.name));
 
-	i2c->clk = clk_get(&dev->dev, NULL);
+	i2c->clk = devm_clk_get(&dev->dev, NULL);
 	if (IS_ERR(i2c->clk)) {
-		ret = PTR_ERR(i2c->clk);
-		goto eclk;
-	}
-
-	i2c->reg_base = ioremap(res->start, resource_size(res));
-	if (!i2c->reg_base) {
-		ret = -EIO;
-		goto eremap;
+		dev_err(&dev->dev, "failed to get the clk: %ld\n", PTR_ERR(i2c->clk));
+		return PTR_ERR(i2c->clk);
 	}
 
 	i2c->reg_ibmr = i2c->reg_base + pxa_reg_layout[i2c_type].ibmr;
···
 		i2c->adap.algo = &i2c_pxa_pio_algorithm;
 	} else {
 		i2c->adap.algo = &i2c_pxa_algorithm;
-		ret = request_irq(irq, i2c_pxa_handler, IRQF_SHARED,
-				  dev_name(&dev->dev), i2c);
-		if (ret)
+		ret = devm_request_irq(&dev->dev, irq, i2c_pxa_handler,
+				IRQF_SHARED | IRQF_NO_SUSPEND,
+				dev_name(&dev->dev), i2c);
+		if (ret) {
+			dev_err(&dev->dev, "failed to request irq: %d\n", ret);
 			goto ereqirq;
+		}
 	}
 
 	i2c_pxa_reset(i2c);
···
 
 	ret = i2c_add_numbered_adapter(&i2c->adap);
 	if (ret < 0) {
-		printk(KERN_INFO "I2C: Failed to add bus\n");
-		goto eadapt;
+		dev_err(&dev->dev, "failed to add bus: %d\n", ret);
+		goto ereqirq;
 	}
 
 	platform_set_drvdata(dev, i2c);
 
 #ifdef CONFIG_I2C_PXA_SLAVE
-	printk(KERN_INFO "I2C: %s: PXA I2C adapter, slave address %d\n",
-	       dev_name(&i2c->adap.dev), i2c->slave_addr);
+	dev_info(&i2c->adap.dev, " PXA I2C adapter, slave address %d\n",
+		i2c->slave_addr);
 #else
-	printk(KERN_INFO "I2C: %s: PXA I2C adapter\n",
-	       dev_name(&i2c->adap.dev));
+	dev_info(&i2c->adap.dev, " PXA I2C adapter\n");
 #endif
 	return 0;
 
-eadapt:
-	if (!i2c->use_pio)
-		free_irq(irq, i2c);
 ereqirq:
 	clk_disable_unprepare(i2c->clk);
-	iounmap(i2c->reg_base);
-eremap:
-	clk_put(i2c->clk);
-eclk:
-	kfree(i2c);
-emalloc:
-	release_mem_region(res->start, resource_size(res));
 	return ret;
 }
 
···
 	struct pxa_i2c *i2c = platform_get_drvdata(dev);
 
 	i2c_del_adapter(&i2c->adap);
-	if (!i2c->use_pio)
-		free_irq(i2c->irq, i2c);
 
 	clk_disable_unprepare(i2c->clk);
-	clk_put(i2c->clk);
-
-	iounmap(i2c->reg_base);
-	release_mem_region(i2c->iobase, i2c->iosize);
-	kfree(i2c);
 
 	return 0;
 }

drivers/i2c/busses/i2c-tegra.c

···
 #define I2C_HEADER_CONTINUE_XFER		(1<<15)
 #define I2C_HEADER_MASTER_ADDR_SHIFT		12
 #define I2C_HEADER_SLAVE_ADDR_SHIFT		1
+
+#define I2C_CONFIG_LOAD				0x08C
+#define I2C_MSTR_CONFIG_LOAD			(1 << 0)
+#define I2C_SLV_CONFIG_LOAD			(1 << 1)
+#define I2C_TIMEOUT_CONFIG_LOAD			(1 << 2)
+
 /*
  * msg_end_type: The bus control which need to be send at end of transfer.
  * @MSG_END_STOP: Send stop pulse at end of transfer.
···
  * @has_single_clk_source: The i2c controller has single clock source. Tegra30
  *		and earlier Socs has two clock sources i.e. div-clk and
  *		fast-clk.
+ * @has_config_load_reg: Has the config load register to load the new
+ *		configuration.
  * @clk_divisor_hs_mode: Clock divisor in HS mode.
  * @clk_divisor_std_fast_mode: Clock divisor in standard/fast mode. It is
  *		applicable if there is no fast clock source i.e. single clock
···
 	bool has_continue_xfer_support;
 	bool has_per_pkt_xfer_complete_irq;
 	bool has_single_clk_source;
+	bool has_config_load_reg;
 	int clk_divisor_hs_mode;
 	int clk_divisor_std_fast_mode;
+	u16 clk_divisor_fast_plus_mode;
 };
 
 /**
···
 	size_t msg_buf_remaining;
 	int msg_read;
 	u32 bus_clk_rate;
+	u16 clk_divisor_non_hs_mode;
 	bool is_suspended;
 };
 
···
 	u32 val;
 	int err = 0;
 	u32 clk_divisor;
+	unsigned long timeout = jiffies + HZ;
 
 	err = tegra_i2c_clock_enable(i2c_dev);
 	if (err < 0) {
···
 
 	/* Make sure clock divisor programmed correctly */
 	clk_divisor = i2c_dev->hw->clk_divisor_hs_mode;
-	clk_divisor |= i2c_dev->hw->clk_divisor_std_fast_mode <<
+	clk_divisor |= i2c_dev->clk_divisor_non_hs_mode <<
 					I2C_CLK_DIVISOR_STD_FAST_MODE_SHIFT;
 	i2c_writel(i2c_dev, clk_divisor, I2C_CLK_DIVISOR);
 
···
 
 	if (tegra_i2c_flush_fifos(i2c_dev))
 		err = -ETIMEDOUT;
+
+	if (i2c_dev->hw->has_config_load_reg) {
+		i2c_writel(i2c_dev, I2C_MSTR_CONFIG_LOAD, I2C_CONFIG_LOAD);
+		while (i2c_readl(i2c_dev, I2C_CONFIG_LOAD) != 0) {
+			if (time_after(jiffies, timeout)) {
+				dev_warn(i2c_dev->dev,
+					"timeout waiting for config load\n");
+				return -ETIMEDOUT;
+			}
+			msleep(1);
+		}
+	}
 
 	tegra_i2c_clock_disable(i2c_dev);
 
···
 	.has_single_clk_source = false,
 	.clk_divisor_hs_mode = 3,
 	.clk_divisor_std_fast_mode = 0,
+	.clk_divisor_fast_plus_mode = 0,
+	.has_config_load_reg = false,
 };
 
 static const struct tegra_i2c_hw_feature tegra30_i2c_hw = {
···
 	.has_single_clk_source = false,
 	.clk_divisor_hs_mode = 3,
 	.clk_divisor_std_fast_mode = 0,
+	.clk_divisor_fast_plus_mode = 0,
+	.has_config_load_reg = false,
 };
 
 static const struct tegra_i2c_hw_feature tegra114_i2c_hw = {
···
 	.has_single_clk_source = true,
 	.clk_divisor_hs_mode = 1,
 	.clk_divisor_std_fast_mode = 0x19,
+	.clk_divisor_fast_plus_mode = 0x10,
+	.has_config_load_reg = false,
+};
+
+static const struct tegra_i2c_hw_feature tegra124_i2c_hw = {
+	.has_continue_xfer_support = true,
+	.has_per_pkt_xfer_complete_irq = true,
+	.has_single_clk_source = true,
+	.clk_divisor_hs_mode = 1,
+	.clk_divisor_std_fast_mode = 0x19,
+	.clk_divisor_fast_plus_mode = 0x10,
+	.has_config_load_reg = true,
 };
 
 /* Match table for of_platform binding */
 static const struct of_device_id tegra_i2c_of_match[] = {
+	{ .compatible = "nvidia,tegra124-i2c", .data = &tegra124_i2c_hw, },
 	{ .compatible = "nvidia,tegra114-i2c", .data = &tegra114_i2c_hw, },
 	{ .compatible = "nvidia,tegra30-i2c", .data = &tegra30_i2c_hw, },
 	{ .compatible = "nvidia,tegra20-i2c", .data = &tegra20_i2c_hw, },
···
 		}
 	}
 
-	clk_multiplier *= (i2c_dev->hw->clk_divisor_std_fast_mode + 1);
+	i2c_dev->clk_divisor_non_hs_mode =
+			i2c_dev->hw->clk_divisor_std_fast_mode;
+	if (i2c_dev->hw->clk_divisor_fast_plus_mode &&
+		(i2c_dev->bus_clk_rate == 1000000))
+		i2c_dev->clk_divisor_non_hs_mode =
+			i2c_dev->hw->clk_divisor_fast_plus_mode;
+
+	clk_multiplier *= (i2c_dev->clk_divisor_non_hs_mode + 1);
 	ret = clk_set_rate(i2c_dev->div_clk,
 			   i2c_dev->bus_clk_rate * clk_multiplier);
 	if (ret) {

drivers/i2c/busses/i2c-viperboard.c

···
 			VPRBRD_USB_REQUEST_I2C_FREQ, VPRBRD_USB_TYPE_OUT,
 			0x0000, 0x0000, &vb_i2c->bus_freq_param, 1,
 			VPRBRD_USB_TIMEOUT_MS);
-	    if (ret != 1) {
-		dev_err(&pdev->dev,
-			"failure setting i2c_bus_freq to %d\n", i2c_bus_freq);
-		return -EIO;
-	    }
+		if (ret != 1) {
+			dev_err(&pdev->dev, "failure setting i2c_bus_freq to %d\n",
+				i2c_bus_freq);
+			return -EIO;
+		}
 	} else {
 		dev_err(&pdev->dev,
 			"invalid i2c_bus_freq setting:%d\n", i2c_bus_freq);

drivers/i2c/busses/i2c-xgene-slimpro.c

···
 	int rc;
 
 	paddr = dma_map_single(ctx->dev, ctx->dma_buffer, readlen, DMA_FROM_DEVICE);
-	rc = dma_mapping_error(ctx->dev, paddr);
-	if (rc) {
+	if (dma_mapping_error(ctx->dev, paddr)) {
 		dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n",
 			ctx->dma_buffer);
+		rc = -ENOMEM;
 		goto err;
 	}
 
···
 	memcpy(ctx->dma_buffer, data, writelen);
 	paddr = dma_map_single(ctx->dev, ctx->dma_buffer, writelen,
 			       DMA_TO_DEVICE);
-	rc = dma_mapping_error(ctx->dev, paddr);
-	if (rc) {
+	if (dma_mapping_error(ctx->dev, paddr)) {
 		dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n",
 			ctx->dma_buffer);
+		rc = -ENOMEM;
 		goto err;
 	}
 

drivers/i2c/busses/i2c-xiic.c

···
 	/* Enable interrupts */
 	xiic_setreg32(i2c, XIIC_DGIER_OFFSET, XIIC_GINTR_ENABLE_MASK);
 
-	xiic_irq_clr_en(i2c, XIIC_INTR_AAS_MASK | XIIC_INTR_ARB_LOST_MASK);
+	xiic_irq_clr_en(i2c, XIIC_INTR_ARB_LOST_MASK);
 }
 
 static void xiic_deinit(struct xiic_i2c *i2c)
···
 	wake_up(&i2c->wait);
 }
 
-static void xiic_process(struct xiic_i2c *i2c)
+static irqreturn_t xiic_process(int irq, void *dev_id)
 {
+	struct xiic_i2c *i2c = dev_id;
 	u32 pend, isr, ier;
 	u32 clr = 0;
 
···
 	 * To find which interrupts are pending; AND interrupts pending with
 	 * interrupts masked.
 	 */
+	spin_lock(&i2c->lock);
 	isr = xiic_getreg32(i2c, XIIC_IISR_OFFSET);
 	ier = xiic_getreg32(i2c, XIIC_IIER_OFFSET);
 	pend = isr & ier;
···
 		__func__, xiic_getreg8(i2c, XIIC_SR_REG_OFFSET),
 		i2c->tx_msg, i2c->nmsgs);
 
-	/* Do not processes a devices interrupts if the device has no
-	 * interrupts pending
-	 */
-	if (!pend)
-		return;
 
 	/* Service requesting interrupt */
 	if ((pend & XIIC_INTR_ARB_LOST_MASK) ||
···
 		 */
 		xiic_reinit(i2c);
 
+		if (i2c->rx_msg)
+			xiic_wakeup(i2c, STATE_ERROR);
 		if (i2c->tx_msg)
 			xiic_wakeup(i2c, STATE_ERROR);
-
-	} else if (pend & XIIC_INTR_RX_FULL_MASK) {
+	}
+	if (pend & XIIC_INTR_RX_FULL_MASK) {
 		/* Receive register/FIFO is full */
 
-		clr = XIIC_INTR_RX_FULL_MASK;
+		clr |= XIIC_INTR_RX_FULL_MASK;
 		if (!i2c->rx_msg) {
 			dev_dbg(i2c->adap.dev.parent,
 				"%s unexpexted RX IRQ\n", __func__);
···
 				__xiic_start_xfer(i2c);
 			}
 		}
-	} else if (pend & XIIC_INTR_BNB_MASK) {
+	}
+	if (pend & XIIC_INTR_BNB_MASK) {
 		/* IIC bus has transitioned to not busy */
-		clr = XIIC_INTR_BNB_MASK;
+		clr |= XIIC_INTR_BNB_MASK;
 
 		/* The bus is not busy, disable BusNotBusy interrupt */
 		xiic_irq_dis(i2c, XIIC_INTR_BNB_MASK);
···
 			xiic_wakeup(i2c, STATE_DONE);
 		else
 			xiic_wakeup(i2c, STATE_ERROR);
-
-	} else if (pend & (XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_HALF_MASK)) {
+	}
+	if (pend & (XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_HALF_MASK)) {
 		/* Transmit register/FIFO is empty or ½ empty */
 
-		clr = pend &
-			(XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_HALF_MASK);
+		clr |= (pend &
+			(XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_HALF_MASK));
 
 		if (!i2c->tx_msg) {
 			dev_dbg(i2c->adap.dev.parent,
···
 			 * make sure to disable tx half
 			 */
 			xiic_irq_dis(i2c, XIIC_INTR_TX_HALF_MASK);
-	} else {
-		/* got IRQ which is not acked */
-		dev_err(i2c->adap.dev.parent, "%s Got unexpected IRQ\n",
-			__func__);
-		clr = pend;
 	}
 out:
 	dev_dbg(i2c->adap.dev.parent, "%s clr: 0x%x\n", __func__, clr);
 
 	xiic_setreg32(i2c, XIIC_IISR_OFFSET, clr);
+	spin_unlock(&i2c->lock);
+	return IRQ_HANDLED;
 }
 
 static int xiic_bus_busy(struct xiic_i2c *i2c)
···
 	 */
 	err = xiic_bus_busy(i2c);
 	while (err && tries--) {
-		mdelay(1);
+		msleep(1);
 		err = xiic_bus_busy(i2c);
 	}
 
···
 static irqreturn_t xiic_isr(int irq, void *dev_id)
 {
 	struct xiic_i2c *i2c = dev_id;
-
-	spin_lock(&i2c->lock);
-	/* disable interrupts globally */
-	xiic_setreg32(i2c, XIIC_DGIER_OFFSET, 0);
+	u32 pend, isr, ier;
+	irqreturn_t ret = IRQ_NONE;
+	/* Do not processes a devices interrupts if the device has no
+	 * interrupts pending
+	 */
 
 	dev_dbg(i2c->adap.dev.parent, "%s entry\n", __func__);
 
-	xiic_process(i2c);
+	isr = xiic_getreg32(i2c, XIIC_IISR_OFFSET);
+	ier = xiic_getreg32(i2c, XIIC_IIER_OFFSET);
+	pend = isr & ier;
+	if (pend)
+		ret = IRQ_WAKE_THREAD;
 
-	xiic_setreg32(i2c, XIIC_DGIER_OFFSET, XIIC_GINTR_ENABLE_MASK);
-	spin_unlock(&i2c->lock);
-
-	return IRQ_HANDLED;
+	return ret;
 }
 
 static void __xiic_start_xfer(struct xiic_i2c *i2c)
···
 
 static void xiic_start_xfer(struct xiic_i2c *i2c)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(&i2c->lock, flags);
-	xiic_reinit(i2c);
-	/* disable interrupts globally */
-	xiic_setreg32(i2c, XIIC_DGIER_OFFSET, 0);
-	spin_unlock_irqrestore(&i2c->lock, flags);
 
 	__xiic_start_xfer(i2c);
-	xiic_setreg32(i2c, XIIC_DGIER_OFFSET, XIIC_GINTR_ENABLE_MASK);
 }
 
 static int xiic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
···
 	spin_lock_init(&i2c->lock);
 	init_waitqueue_head(&i2c->wait);
 
-	ret = devm_request_irq(&pdev->dev, irq, xiic_isr, 0, pdev->name, i2c);
+	ret = devm_request_threaded_irq(&pdev->dev, irq, xiic_isr,
+					xiic_process, IRQF_ONESHOT,
+					pdev->name, i2c);
+
 	if (ret < 0) {
 		dev_err(&pdev->dev, "Cannot claim IRQ\n");
 		return ret;

drivers/i2c/i2c-core.c

···
    I2C slave support (c) 2014 by Wolfram Sang <[e-mail]>
  */
 
+#include <dt-bindings/i2c/i2c.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/delay.h>
···
 #include <linux/rwsem.h>
 #include <linux/pm_runtime.h>
 #include <linux/pm_domain.h>
+#include <linux/pm_wakeirq.h>
 #include <linux/acpi.h>
 #include <linux/jump_label.h>
 #include <asm/uaccess.h>
···
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/i2c.h>
+
+#define I2C_ADDR_OFFSET_TEN_BIT	0xa000
+#define I2C_ADDR_OFFSET_SLAVE	0x1000
 
 /* core_lock protects i2c_adapter_idr, and guarantees
    that device detection, deletion of detected devices, and attach_adapter
···
 	if (!client->irq) {
 		int irq = -ENOENT;
 
-		if (dev->of_node)
-			irq = of_irq_get(dev->of_node, 0);
-		else if (ACPI_COMPANION(dev))
+		if (dev->of_node) {
+			irq = of_irq_get_byname(dev->of_node, "irq");
+			if (irq == -EINVAL || irq == -ENODATA)
+				irq = of_irq_get(dev->of_node, 0);
+		} else if (ACPI_COMPANION(dev)) {
 			irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
-
+		}
 		if (irq == -EPROBE_DEFER)
 			return irq;
 		if (irq < 0)
···
 	if (!driver->probe || !driver->id_table)
 		return -ENODEV;
 
-	if (!device_can_wakeup(&client->dev))
-		device_init_wakeup(&client->dev,
-					client->flags & I2C_CLIENT_WAKE);
+	if (client->flags & I2C_CLIENT_WAKE) {
+		int wakeirq = -ENOENT;
+
+		if (dev->of_node) {
+			wakeirq = of_irq_get_byname(dev->of_node, "wakeup");
+			if (wakeirq == -EPROBE_DEFER)
+				return wakeirq;
+		}
+
+		device_init_wakeup(&client->dev, true);
+
+		if (wakeirq > 0 && wakeirq != client->irq)
+			status = dev_pm_set_dedicated_wake_irq(dev, wakeirq);
+		else if (client->irq > 0)
+			status = dev_pm_set_wake_irq(dev, wakeirq);
+		else
+			status = 0;
+
+		if (status)
+			dev_warn(&client->dev, "failed to set up wakeup irq");
+	}
+
 	dev_dbg(dev, "probe\n");
 
 	status = of_clk_set_defaults(dev->of_node, false);
 	if (status < 0)
-		return status;
+		goto err_clear_wakeup_irq;
 
 	status = dev_pm_domain_attach(&client->dev, true);
 	if (status != -EPROBE_DEFER) {
 		status = driver->probe(client, i2c_match_id(driver->id_table,
 					client));
 		if (status)
-			dev_pm_domain_detach(&client->dev, true);
+			goto err_detach_pm_domain;
 	}
 
+	return 0;
+
+err_detach_pm_domain:
+	dev_pm_domain_detach(&client->dev, true);
+err_clear_wakeup_irq:
+	dev_pm_clear_wake_irq(&client->dev);
+	device_init_wakeup(&client->dev, false);
 	return status;
 }
 
···
 	}
 
 	dev_pm_domain_detach(&client->dev, true);
+
+	dev_pm_clear_wake_irq(&client->dev);
+	device_init_wakeup(&client->dev, false);
+
 	return status;
 }
 
···
 EXPORT_SYMBOL(i2c_verify_client);
 
 
+/* Return a unique address which takes the flags of the client into account */
+static unsigned short i2c_encode_flags_to_addr(struct i2c_client *client)
+{
+	unsigned short addr = client->addr;
+
+	/* For some client flags, add an arbitrary offset to avoid collisions */
+	if (client->flags & I2C_CLIENT_TEN)
+		addr |= I2C_ADDR_OFFSET_TEN_BIT;
+
+	if (client->flags & I2C_CLIENT_SLAVE)
+		addr |= I2C_ADDR_OFFSET_SLAVE;
+
+	return addr;
+}
+
 /* This is a permissive address validity check, I2C address map constraints
  * are purposely not enforced, except for the general call address. */
-static int i2c_check_client_addr_validity(const struct i2c_client *client)
+static int i2c_check_addr_validity(unsigned addr, unsigned short flags)
 {
-	if (client->flags & I2C_CLIENT_TEN) {
+	if (flags & I2C_CLIENT_TEN) {
 		/* 10-bit address, all values are valid */
-		if (client->addr > 0x3ff)
+		if (addr > 0x3ff)
 			return -EINVAL;
 	} else {
 		/* 7-bit address, reject the general call address */
-		if (client->addr == 0x00 || client->addr > 0x7f)
+		if (addr == 0x00 || addr > 0x7f)
 			return -EINVAL;
 	}
 	return 0;
···
  * device uses a reserved address, then it shouldn't be probed. 7-bit
  * addressing is assumed, 10-bit address devices are rare and should be
  * explicitly enumerated. */
-static int i2c_check_addr_validity(unsigned short addr)
+static int i2c_check_7bit_addr_validity_strict(unsigned short addr)
 {
 	/*
 	 * Reserved addresses per I2C specification:
···
 	struct i2c_client	*client = i2c_verify_client(dev);
 	int			addr = *(int *)addrp;
 
-	if (client && client->addr == addr)
+	if (client && i2c_encode_flags_to_addr(client) == addr)
 		return -EBUSY;
 	return 0;
 }
···
 		return;
 	}
 
-	/* For 10-bit clients, add an arbitrary offset to avoid collisions */
 	dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap),
-		     client->addr | ((client->flags & I2C_CLIENT_TEN)
-				     ? 0xa000 : 0));
+		     i2c_encode_flags_to_addr(client));
 }
 
 /**
···
 
 	strlcpy(client->name, info->type, sizeof(client->name));
 
-	/* Check for address validity */
-	status = i2c_check_client_addr_validity(client);
+	status = i2c_check_addr_validity(client->addr, client->flags);
 	if (status) {
 		dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n",
 			client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr);
···
 	}
 
 	/* Check for address business */
-	status = i2c_check_addr_busy(adap, client->addr);
+	status = i2c_check_addr_busy(adap, i2c_encode_flags_to_addr(client));
 	if (status)
 		goto out_err;
 
···
 		return -EINVAL;
 	}
 
+	if ((info.addr & I2C_ADDR_OFFSET_TEN_BIT) == I2C_ADDR_OFFSET_TEN_BIT) {
+		info.addr &= ~I2C_ADDR_OFFSET_TEN_BIT;
+		info.flags |= I2C_CLIENT_TEN;
+	}
+
+	if (info.addr & I2C_ADDR_OFFSET_SLAVE) {
+		info.addr &= ~I2C_ADDR_OFFSET_SLAVE;
+		info.flags |= I2C_CLIENT_SLAVE;
+	}
+
 	client = i2c_new_device(adap, &info);
 	if (!client)
 		return -EINVAL;
···
 			  i2c_adapter_depth(adap));
 	list_for_each_entry_safe(client, next, &adap->userspace_clients,
 				 detected) {
-		if (client->addr == addr) {
+		if (i2c_encode_flags_to_addr(client) == addr) {
 			dev_info(dev, "%s: Deleting device %s at 0x%02hx\n",
 				 "delete_device", client->name, client->addr);
 
···
 	struct i2c_client *result;
 	struct i2c_board_info info = {};
 	struct dev_archdata dev_ad = {};
-	const __be32 *addr;
+	const __be32 *addr_be;
+	u32 addr;
 	int len;
 
 	dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name);
···
 		return ERR_PTR(-EINVAL);
 	}
 
-	addr = of_get_property(node, "reg", &len);
-	if (!addr || (len < sizeof(*addr))) {
+	addr_be = of_get_property(node, "reg", &len);
+	if (!addr_be || (len < sizeof(*addr_be))) {
 		dev_err(&adap->dev, "of_i2c: invalid reg on %s\n",
 			node->full_name);
 		return ERR_PTR(-EINVAL);
 	}
 
-	info.addr = be32_to_cpup(addr);
-	if (info.addr > (1 << 10) - 1) {
+	addr = be32_to_cpup(addr_be);
+	if (addr & I2C_TEN_BIT_ADDRESS) {
+		addr &= ~I2C_TEN_BIT_ADDRESS;
+		info.flags |= I2C_CLIENT_TEN;
+	}
+
+	if (addr & I2C_OWN_SLAVE_ADDRESS) {
+		addr &= ~I2C_OWN_SLAVE_ADDRESS;
+		info.flags |= I2C_CLIENT_SLAVE;
+	}
+
+	if (i2c_check_addr_validity(addr, info.flags)) {
 		dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n",
 			info.addr, node->full_name);
 		return ERR_PTR(-EINVAL);
 	}
 
+	info.addr = addr;
 	info.of_node = of_node_get(node);
 	info.archdata = &dev_ad;
 
···
 	return adapter;
 }
 EXPORT_SYMBOL(of_find_i2c_adapter_by_node);
+
+/* must call i2c_put_adapter() when done with returned i2c_adapter device */
+struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node)
+{
+	struct i2c_adapter *adapter;
+
+	adapter = of_find_i2c_adapter_by_node(node);
+	if (!adapter)
+		return NULL;
+
+	if (!try_module_get(adapter->owner)) {
+		put_device(&adapter->dev);
+		adapter = NULL;
+	}
+
+	return adapter;
+}
+EXPORT_SYMBOL(of_get_i2c_adapter_by_node);
 #else
 static void of_i2c_register_devices(struct i2c_adapter *adap) { }
 #endif /* CONFIG_OF */
···
 	int err;
 
 	/* Make sure the address is valid */
-	err = i2c_check_addr_validity(addr);
+	err = i2c_check_7bit_addr_validity_strict(addr);
 	if (err) {
 		dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n",
 			 addr);
 		return err;
 	}
 
-	/* Skip if already in use */
+	/* Skip if already in use (7 bit, no need to encode flags) */
 	if (i2c_check_addr_busy(adapter, addr))
 		return 0;
 
···
 
 	for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) {
 		/* Check address validity */
-		if (i2c_check_addr_validity(addr_list[i]) < 0) {
+		if (i2c_check_7bit_addr_validity_strict(addr_list[i]) < 0) {
 			dev_warn(&adap->dev, "Invalid 7-bit address "
 				 "0x%02x\n", addr_list[i]);
 			continue;
 		}
 
-		/* Check address availability */
+		/* Check address availability (7 bit, no need to encode flags) */
 		if (i2c_check_addr_busy(adap, addr_list[i])) {
 			dev_dbg(&adap->dev, "Address 0x%02x already in "
 				"use, not probing\n", addr_list[i]);
···
 
 	mutex_lock(&core_lock);
 	adapter = idr_find(&i2c_adapter_idr, nr);
-	if (adapter && !try_module_get(adapter->owner))
+	if (!adapter)
+		goto exit;
+
+	if (try_module_get(adapter->owner))
+		get_device(&adapter->dev);
+	else
 		adapter = NULL;
 
+ exit:
 	mutex_unlock(&core_lock);
 	return adapter;
 }
···
 
 void i2c_put_adapter(struct i2c_adapter *adap)
 {
-	if (adap)
-		module_put(adap->owner);
+	if (!adap)
+		return;
+
+	put_device(&adap->dev);
+	module_put(adap->owner);
 }
 EXPORT_SYMBOL(i2c_put_adapter);
 
···
 }
 EXPORT_SYMBOL(i2c_smbus_xfer);
 
+/**
+ * i2c_smbus_read_i2c_block_data_or_emulated - read block or emulate
+ * @client: Handle to slave device
+ * @command: Byte interpreted by slave
+ * @length: Size of data block; SMBus allows at most I2C_SMBUS_BLOCK_MAX bytes
+ * @values: Byte array into which data will be read; big enough to hold
+ *	the data returned by the slave.  SMBus allows at most
+ *	I2C_SMBUS_BLOCK_MAX bytes.
+ *
+ * This executes the SMBus "block read" protocol if supported by the adapter.
+ * If block read is not supported, it emulates it using either word or byte
+ * read protocols depending on availability.
+ *
+ * The addresses of the I2C slave device that are accessed with this function
+ * must be mapped to a linear region, so that a block read will have the same
+ * effect as a byte read. Before using this function you must double-check
+ * if the I2C slave does support exchanging a block transfer with a byte
+ * transfer.
+ */
+s32 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client,
+					      u8 command, u8 length, u8 *values)
+{
+	u8 i = 0;
+	int status;
+
+	if (length > I2C_SMBUS_BLOCK_MAX)
+		length = I2C_SMBUS_BLOCK_MAX;
+
+	if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK))
+		return i2c_smbus_read_i2c_block_data(client, command, length, values);
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA))
+		return -EOPNOTSUPP;
+
+	if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_WORD_DATA)) {
+		while ((i + 2) <= length) {
+			status = i2c_smbus_read_word_data(client, command + i);
+			if (status < 0)
+				return status;
+			values[i] = status & 0xff;
+			values[i + 1] = status >> 8;
+			i += 2;
+		}
+	}
+
+	while (i < length) {
+		status = i2c_smbus_read_byte_data(client, command + i);
+		if (status < 0)
+			return status;
+		values[i] = status;
+		i++;
+	}
+
+	return i;
+}
+EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data_or_emulated);
+
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
 int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb)
 {
···
 		return -EINVAL;
 	}
 
+	if (!(client->flags & I2C_CLIENT_SLAVE))
+		dev_warn(&client->dev, "%s: client slave flag not set. You might see address collisions\n",
+			 __func__);
+
 	if (!(client->flags & I2C_CLIENT_TEN)) {
 		/* Enforce stricter address checking */
-		ret = i2c_check_addr_validity(client->addr);
+		ret = i2c_check_7bit_addr_validity_strict(client->addr);
 		if (ret) {
 			dev_err(&client->dev, "%s: invalid address\n", __func__);
 			return ret;

drivers/i2c/i2c-slave-eeprom.c

···
 static struct i2c_driver i2c_slave_eeprom_driver = {
 	.driver = {
 		.name = "i2c-slave-eeprom",
-		.owner = THIS_MODULE,
 	},
 	.probe = i2c_slave_eeprom_probe,
 	.remove = i2c_slave_eeprom_remove,

drivers/i2c/muxes/Kconfig

···
 	  This driver can also be built as a module. If so, the module will be
 	  called pinctrl-i2cmux.
 
+config I2C_MUX_REG
+	tristate "Register-based I2C multiplexer"
+	help
+	  If you say yes to this option, support will be included for a
+	  register based I2C multiplexer. This driver provides access to
+	  I2C busses connected through a MUX, which is controlled
+	  by a single register.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-mux-reg.
+
 endmenu

drivers/i2c/muxes/Makefile

···
 obj-$(CONFIG_I2C_MUX_PCA9541)	+= i2c-mux-pca9541.o
 obj-$(CONFIG_I2C_MUX_PCA954x)	+= i2c-mux-pca954x.o
 obj-$(CONFIG_I2C_MUX_PINCTRL)	+= i2c-mux-pinctrl.o
+obj-$(CONFIG_I2C_MUX_REG)	+= i2c-mux-reg.o
 
 ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG

drivers/i2c/muxes/i2c-arb-gpio-challenge.c

···
 		dev_err(dev, "Cannot parse i2c-parent\n");
 		return -EINVAL;
 	}
-	arb->parent = of_find_i2c_adapter_by_node(parent_np);
+	arb->parent = of_get_i2c_adapter_by_node(parent_np);
+	of_node_put(parent_np);
 	if (!arb->parent) {
 		dev_err(dev, "Cannot find parent bus\n");
 		return -EPROBE_DEFER;

drivers/i2c/muxes/i2c-mux-gpio.c

···
 		return -ENODEV;
 	}
 	adapter = of_find_i2c_adapter_by_node(adapter_np);
+	of_node_put(adapter_np);
 	if (!adapter)
 		return -EPROBE_DEFER;
 

drivers/i2c/muxes/i2c-mux-pca9541.c

···
 static struct i2c_driver pca9541_driver = {
 	.driver = {
 		   .name = "pca9541",
-		   .owner = THIS_MODULE,
 		   },
 	.probe = pca9541_probe,
 	.remove = pca9541_remove,

drivers/i2c/muxes/i2c-mux-pca954x.c

···
 	.driver		= {
 		.name	= "pca954x",
 		.pm	= &pca954x_pm,
-		.owner	= THIS_MODULE,
 	},
 	.probe		= pca954x_probe,
 	.remove		= pca954x_remove,

drivers/i2c/muxes/i2c-mux-pinctrl.c

···
 		return -ENODEV;
 	}
 	adapter = of_find_i2c_adapter_by_node(adapter_np);
+	of_node_put(adapter_np);
 	if (!adapter) {
 		dev_err(mux->dev, "Cannot find parent bus\n");
 		return -EPROBE_DEFER;

drivers/i2c/muxes/i2c-mux-reg.c

···
+/*
+ * I2C multiplexer using a single register
+ *
+ * Copyright 2015 Freescale Semiconductor
+ * York Sun  <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/platform_data/i2c-mux-reg.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+struct regmux {
+	struct i2c_adapter *parent;
+	struct i2c_adapter **adap; /* child busses */
+	struct i2c_mux_reg_platform_data data;
+};
+
+static int i2c_mux_reg_set(const struct regmux *mux, unsigned int chan_id)
+{
+	if (!mux->data.reg)
+		return -EINVAL;
+
+	/*
+	 * Write to the register, followed by a read to ensure the write is
+	 * completed on a "posted" bus, for example PCI or write buffers.
+	 * The endianness of reading doesn't matter and the return data
+	 * is not used.
+	 */
+	switch (mux->data.reg_size) {
+	case 4:
+		if (mux->data.little_endian)
+			iowrite32(chan_id, mux->data.reg);
+		else
+			iowrite32be(chan_id, mux->data.reg);
+		if (!mux->data.write_only)
+			ioread32(mux->data.reg);
+		break;
+	case 2:
+		if (mux->data.little_endian)
+			iowrite16(chan_id, mux->data.reg);
+		else
+			iowrite16be(chan_id, mux->data.reg);
+		if (!mux->data.write_only)
+			ioread16(mux->data.reg);
+		break;
+	case 1:
+		iowrite8(chan_id, mux->data.reg);
+		if (!mux->data.write_only)
+			ioread8(mux->data.reg);
+		break;
+	}
+
+	return 0;
+}
+
+static int i2c_mux_reg_select(struct i2c_adapter *adap, void *data,
+			      unsigned int chan)
+{
+	struct regmux *mux = data;
+
+	return i2c_mux_reg_set(mux, chan);
+}
+
+static int i2c_mux_reg_deselect(struct i2c_adapter *adap, void *data,
+				unsigned int chan)
+{
+	struct regmux *mux = data;
+
+	if (mux->data.idle_in_use)
+		return i2c_mux_reg_set(mux, mux->data.idle);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static int i2c_mux_reg_probe_dt(struct regmux *mux,
+					struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device_node *adapter_np, *child;
+	struct i2c_adapter *adapter;
+	struct resource res;
+	unsigned *values;
+	int i = 0;
+
+	if (!np)
+		return -ENODEV;
+
+	adapter_np = of_parse_phandle(np, "i2c-parent", 0);
+	if (!adapter_np) {
+		dev_err(&pdev->dev, "Cannot parse i2c-parent\n");
+		return -ENODEV;
+	}
+	adapter = of_find_i2c_adapter_by_node(adapter_np);
+	of_node_put(adapter_np);
+	if (!adapter)
+		return -EPROBE_DEFER;
+
+	mux->parent = adapter;
+	mux->data.parent = i2c_adapter_id(adapter);
+	put_device(&adapter->dev);
+
+	mux->data.n_values = of_get_child_count(np);
+	if (of_find_property(np, "little-endian", NULL)) {
+		mux->data.little_endian = true;
+	} else if (of_find_property(np, "big-endian", NULL)) {
+		mux->data.little_endian = false;
+	} else {
+#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : \
+	defined(__LITTLE_ENDIAN)
+		mux->data.little_endian = true;
+#elif defined(__BYTE_ORDER) ? __BYTE_ORDER == __BIG_ENDIAN : \
+	defined(__BIG_ENDIAN)
+		mux->data.little_endian = false;
+#else
+#error Endianness not defined?
+#endif
+	}
+	if (of_find_property(np, "write-only", NULL))
+		mux->data.write_only = true;
+	else
+		mux->data.write_only = false;
+
+	values = devm_kzalloc(&pdev->dev,
+			      sizeof(*mux->data.values) * mux->data.n_values,
+			      GFP_KERNEL);
+	if (!values) {
+		dev_err(&pdev->dev, "Cannot allocate values array");
+		return -ENOMEM;
+	}
+
+	for_each_child_of_node(np, child) {
+		of_property_read_u32(child, "reg", values + i);
+		i++;
+	}
+	mux->data.values = values;
+
+	if (!of_property_read_u32(np, "idle-state", &mux->data.idle))
+		mux->data.idle_in_use = true;
+
+	/* map address from "reg" if exists */
+	if (of_address_to_resource(np, 0, &res)) {
+		mux->data.reg_size = resource_size(&res);
+		mux->data.reg = devm_ioremap_resource(&pdev->dev, &res);
+		if (IS_ERR(mux->data.reg))
+			return PTR_ERR(mux->data.reg);
+	}
+
+	return 0;
+}
+#else
+static int i2c_mux_reg_probe_dt(struct regmux *mux,
+					struct platform_device *pdev)
+{
+	return 0;
+}
+#endif
+
+static int i2c_mux_reg_probe(struct platform_device *pdev)
+{
+	struct regmux *mux;
+	struct i2c_adapter *parent;
+	struct resource *res;
+	int (*deselect)(struct i2c_adapter *, void *, u32);
+	unsigned int class;
+	int i, ret, nr;
+
+	mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL);
+	if (!mux)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, mux);
+
+	if (dev_get_platdata(&pdev->dev)) {
+		memcpy(&mux->data, dev_get_platdata(&pdev->dev),
+			sizeof(mux->data));
+
+		parent = i2c_get_adapter(mux->data.parent);
+		if (!parent)
+			return -EPROBE_DEFER;
+
+		mux->parent = parent;
+	} else {
+		ret = i2c_mux_reg_probe_dt(mux, pdev);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "Error parsing device tree");
+			return ret;
+		}
+	}
+
+	if (!mux->data.reg) {
+		dev_info(&pdev->dev,
+			"Register not set, using platform resource\n");
+		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+		mux->data.reg_size = resource_size(res);
+		mux->data.reg = devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(mux->data.reg))
+			return PTR_ERR(mux->data.reg);
+	}
+
+	if (mux->data.reg_size != 4 && mux->data.reg_size != 2 &&
+	    mux->data.reg_size != 1) {
+		dev_err(&pdev->dev, "Invalid register size\n");
+		return -EINVAL;
+	}
+
+	mux->adap = devm_kzalloc(&pdev->dev,
+				 sizeof(*mux->adap) * mux->data.n_values,
+				 GFP_KERNEL);
+	if (!mux->adap) {
+		dev_err(&pdev->dev, "Cannot allocate i2c_adapter structure");
+		return -ENOMEM;
+	}
+
+	if (mux->data.idle_in_use)
+		deselect = i2c_mux_reg_deselect;
+	else
+		deselect = NULL;
+
+	for (i = 0; i < mux->data.n_values; i++) {
+		nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
+		class = mux->data.classes ? mux->data.classes[i] : 0;
+
+		mux->adap[i] = i2c_add_mux_adapter(mux->parent, &pdev->dev, mux,
+						   nr, mux->data.values[i],
+						   class, i2c_mux_reg_select,
+						   deselect);
+		if (!mux->adap[i]) {
+			ret = -ENODEV;
+			dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
+			goto add_adapter_failed;
+		}
+	}
+
+	dev_dbg(&pdev->dev, "%d port mux on %s adapter\n",
+		 mux->data.n_values, mux->parent->name);
+
+	return 0;
+
+add_adapter_failed:
+	for (; i > 0; i--)
+		i2c_del_mux_adapter(mux->adap[i - 1]);
+
+	return ret;
+}
+
+static int i2c_mux_reg_remove(struct platform_device *pdev)
+{
+	struct regmux *mux = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < mux->data.n_values; i++)
+		i2c_del_mux_adapter(mux->adap[i]);
+
+	i2c_put_adapter(mux->parent);
+
+	return 0;
+}
+
+static const struct of_device_id i2c_mux_reg_of_match[] = {
+	{ .compatible = "i2c-mux-reg", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, i2c_mux_reg_of_match);
+
+static struct platform_driver i2c_mux_reg_driver = {
+	.probe	= i2c_mux_reg_probe,
+	.remove	= i2c_mux_reg_remove,
+	.driver	= {
+		.name	= "i2c-mux-reg",
+	},
+};
+
+module_platform_driver(i2c_mux_reg_driver);
+
+MODULE_DESCRIPTION("Register-based I2C multiplexer driver");
+MODULE_AUTHOR("York Sun <[e-mail]>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:i2c-mux-reg");

drivers/misc/eeprom/at24.c

···
 	if (count > io_limit)
 		count = io_limit;
 
-	switch (at24->use_smbus) {
-	case I2C_SMBUS_I2C_BLOCK_DATA:
+	if (at24->use_smbus) {
 		/* Smaller eeproms can work given some SMBus extension calls */
 		if (count > I2C_SMBUS_BLOCK_MAX)
 			count = I2C_SMBUS_BLOCK_MAX;
-		break;
-	case I2C_SMBUS_WORD_DATA:
-		count = 2;
-		break;
-	case I2C_SMBUS_BYTE_DATA:
-		count = 1;
-		break;
-	default:
+	} else {
 		/*
 		 * When we have a better choice than SMBus calls, use a
 		 * combined I2C message. Write address; then read up to
···
 	timeout = jiffies + msecs_to_jiffies(write_timeout);
 	do {
 		read_time = jiffies;
-		switch (at24->use_smbus) {
-		case I2C_SMBUS_I2C_BLOCK_DATA:
-			status = i2c_smbus_read_i2c_block_data(client, offset,
-					count, buf);
-			break;
-		case I2C_SMBUS_WORD_DATA:
-			status = i2c_smbus_read_word_data(client, offset);
-			if (status >= 0) {
-				buf[0] = status & 0xff;
-				buf[1] = status >> 8;
-				status = count;
-			}
-			break;
-		case I2C_SMBUS_BYTE_DATA:
-			status = i2c_smbus_read_byte_data(client, offset);
-			if (status >= 0) {
-				buf[0] = status;
-				status = count;
-			}
-			break;
-		default:
+		if (at24->use_smbus) {
+			status = i2c_smbus_read_i2c_block_data_or_emulated(client, offset,
+									   count, buf);
+		} else {
 			status = i2c_transfer(client->adapter, msg, 2);
 			if (status == 2)
 				status = count;

drivers/misc/eeprom/max6875.c

···
 	{ "max6875", 0 },
 	{ }
 };
+MODULE_DEVICE_TABLE(i2c, max6875_id);
 
 static struct i2c_driver max6875_driver = {
 	.driver = {

drivers/of/irq.c

···
 
 	return of_irq_get(dev, index);
 }
+EXPORT_SYMBOL_GPL(of_irq_get_byname);
 
 /**
  * of_irq_count - Count the number of IRQs a node uses

include/dt-bindings/i2c/i2c.h

···
+/*
+ * This header provides constants for I2C bindings
+ *
+ * Copyright (C) 2015 by Sang Engineering
+ * Copyright (C) 2015 by Renesas Electronics Corporation
+ *
+ * Wolfram Sang <[e-mail]>
+ *
+ * GPLv2 only
+ */
+
+#ifndef _DT_BINDINGS_I2C_I2C_H
+#define _DT_BINDINGS_I2C_I2C_H
+
+#define I2C_TEN_BIT_ADDRESS	(1 << 31)
+#define I2C_OWN_SLAVE_ADDRESS	(1 << 30)
+
+#endif

include/linux/i2c.h

···
 extern s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client,
 					  u8 command, u8 length,
 					  const u8 *values);
+extern s32
+i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client,
+					  u8 command, u8 length, u8 *values);
 #endif /* I2C */
 
 /**
···
 void i2c_unlock_adapter(struct i2c_adapter *);
 
 /*flags for the client struct: */
-#define I2C_CLIENT_PEC	0x04		/* Use Packet Error Checking */
-#define I2C_CLIENT_TEN	0x10		/* we have a ten bit chip address */
+#define I2C_CLIENT_PEC		0x04	/* Use Packet Error Checking */
+#define I2C_CLIENT_TEN		0x10	/* we have a ten bit chip address */
 					/* Must equal I2C_M_TEN below */
-#define I2C_CLIENT_WAKE	0x80		/* for board_info; true iff can wake */
-#define I2C_CLIENT_SCCB	0x9000		/* Use Omnivision SCCB protocol */
+#define I2C_CLIENT_SLAVE	0x20	/* we are the slave */
+#define I2C_CLIENT_WAKE		0x80	/* for board_info; true iff can wake */
+#define I2C_CLIENT_SCCB		0x9000	/* Use Omnivision SCCB protocol */
 					/* Must match I2C_M_STOP|IGNORE_NAK */
 
 /* i2c adapter classes (bitmask) */
···
 /* must call put_device() when done with returned i2c_adapter device */
 extern struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node);
 
+/* must call i2c_put_adapter() when done with returned i2c_adapter device */
+struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node);
 #else
 
 static inline struct i2c_client *of_find_i2c_device_by_node(struct device_node *node)
···
 }
 
 static inline struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node)
+{
+	return NULL;
+}
+
+static inline struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node)
 {
 	return NULL;
 }

include/linux/platform_data/i2c-mux-reg.h

···
+/*
+ * I2C multiplexer using a single register
+ *
+ * Copyright 2015 Freescale Semiconductor
+ * York Sun <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#ifndef __LINUX_PLATFORM_DATA_I2C_MUX_REG_H
+#define __LINUX_PLATFORM_DATA_I2C_MUX_REG_H
+
+/**
+ * struct i2c_mux_reg_platform_data - Platform-dependent data for i2c-mux-reg
+ * @parent: Parent I2C bus adapter number
+ * @base_nr: Base I2C bus number to number adapters from or zero for dynamic
+ * @values: Array of value for each channel
+ * @n_values: Number of multiplexer channels
+ * @little_endian: Indicating if the register is in little endian
+ * @write_only: Reading the register is not allowed by hardware
+ * @classes: Optional I2C auto-detection classes
+ * @idle: Value to write to mux when idle
+ * @idle_in_use: indicate if idle value is in use
+ * @reg: Virtual address of the register to switch channel
+ * @reg_size: register size in bytes
+ */
+struct i2c_mux_reg_platform_data {
+	int parent;
+	int base_nr;
+	const unsigned int *values;
+	int n_values;
+	bool little_endian;
+	bool write_only;
+	const unsigned int *classes;
+	u32 idle;
+	bool idle_in_use;
+	void __iomem *reg;
+	resource_size_t reg_size;
+};
+
+#endif	/* __LINUX_PLATFORM_DATA_I2C_MUX_REG_H */