Merge branch 'i2c/for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:

- the I2C core gained helpers to assist drivers in handling their
suspended state, and drivers were converted to use it

- two new fault-injectors for stress-testing

- bigger refactoring and feature improvements for the ocores,
sh_mobile, and tegra drivers

- platform_data removal for the at24 EEPROM driver

- ... and various improvements and bugfixes all over the subsystem

* 'i2c/for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (69 commits)
i2c: Allow recovery of the initial IRQ by an I2C client device.
i2c: ocores: turn incomplete kdoc into a comment
i2c: designware: Do not allow i2c_dw_xfer() calls while suspended
i2c: tegra: Only display error messages if DMA setup fails
i2c: gpio: fault-injector: add 'inject_panic' injector
i2c: gpio: fault-injector: add 'lose_arbitration' injector
i2c: tegra: remove multi-master support
i2c: tegra: remove master fifo support on tegra186
i2c: tegra: change phrasing, "fallbacking" to "falling back"
i2c: expand minor range when registering chrdev region
i2c: aspeed: Add multi-master use case support
i2c: core-smbus: don't trace smbus_reply data on errors
i2c: ocores: Add support for bus clock via platform data
i2c: ocores: Add support for IO mapper registers.
i2c: ocores: checkpatch fixes
i2c: ocores: add SPDX tag
i2c: ocores: add polling interface
i2c: ocores: do not handle IRQ if IF is not set
i2c: ocores: stop transfer on timeout
i2c: tegra: add i2c interface timing support
...

Documentation/devicetree/bindings/eeprom/at24.txt

···
 
   - address-width: number of address bits (one of 8, 16).
 
+  - num-addresses: total number of i2c slave addresses this device takes
+
 Example:
 
 eeprom@52 {
···
 	reg = <0x52>;
 	pagesize = <32>;
 	wp-gpios = <&gpio1 3 0>;
+	num-addresses = <8>;
 };

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

···
       "mediatek,mt6589-i2c": for MediaTek MT6589
       "mediatek,mt7622-i2c": for MediaTek MT7622
       "mediatek,mt7623-i2c", "mediatek,mt6577-i2c": for MediaTek MT7623
+      "mediatek,mt7629-i2c", "mediatek,mt2712-i2c": for MediaTek MT7629
       "mediatek,mt8173-i2c": for MediaTek MT8173
   - reg: physical base address of the controller and dma base, length of memory
     mapped region.

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

···
+i2c Controller on XScale platforms such as IOP3xx and IXP4xx
+
+Required properties:
+- compatible : Must be one of
+  "intel,iop3xx-i2c"
+  "intel,ixp4xx-i2c";
+- reg
+- #address-cells = <1>;
+- #size-cells = <0>;
+
+Optional properties:
+- Child nodes conforming to i2c bus binding
+
+Example:
+
+i2c@c8011000 {
+	compatible = "intel,ixp4xx-i2c";
+	reg = <0xc8011000 0x18>;
+	interrupts = <33 IRQ_TYPE_LEVEL_LOW>;
+};

Documentation/i2c/fault-codes

···
 	case is when the length of an SMBus block data response
 	(from the SMBus slave) is outside the range 1-32 bytes.
 
+ESHUTDOWN
+	Returned when a transfer was requested using an adapter
+	which is already suspended.
+
 ETIMEDOUT
 	This is returned by drivers when an operation took too much
 	time, and was aborted before it completed.

Documentation/i2c/gpio-fault-injection

···
+=========================
 Linux I2C fault injection
 =========================
 
···
 mounted at /sys/kernel/debug. There will be a separate subdirectory per GPIO
 driven I2C bus. Each subdirectory will contain files to trigger the fault
 injection. They will be described now along with their intended use-cases.
+
+Wire states
+===========
 
 "scl"
 -----
···
 core (see 'struct bus_recovery_info'). However, the bus recovery will not
 succeed because SDA is still pinned low until you manually release it again
 with "echo 1 > sda". A test with an automatic release can be done with the
-following class of fault injectors.
+"incomplete transfers" class of fault injectors.
 
-Introduction to incomplete transfers
-------------------------------------
+Incomplete transfers
+====================
 
 The following fault injectors create situations where SDA will be held low by a
 device. Bus recovery should be able to fix these situations. But please note:
···
 additional STOP conditions to ensure the bus has been released. Otherwise
 random data will be written to a device!
 
+Lost arbitration
+================
+
+Here, we want to simulate the condition where the master under test loses the
+bus arbitration against another master in a multi-master setup.
+
+"lose_arbitration"
+------------------
+
+This file is write only and you need to write the duration of the arbitration
+intereference (in µs, maximum is 100ms). The calling process will then sleep
+and wait for the next bus clock. The process is interruptible, though.
+
+Arbitration lost is achieved by waiting for SCL going down by the master under
+test and then pulling SDA low for some time. So, the I2C address sent out
+should be corrupted and that should be detected properly. That means that the
+address sent out should have a lot of '1' bits to be able to detect corruption.
+There doesn't need to be a device at this address because arbitration lost
+should be detected beforehand. Also note, that SCL going down is monitored
+using interrupts, so the interrupt latency might cause the first bits to be not
+corrupted. A good starting point for using this fault injector on an otherwise
+idle bus is:
+
+# echo 200 > lose_arbitration &
+# i2cget -y <bus_to_test> 0x3f
+
+Panic during transfer
+=====================
+
+This fault injector will create a Kernel panic once the master under test
+started a transfer. This usually means that the state machine of the bus master
+driver will be ungracefully interrupted and the bus may end up in an unusual
+state. Use this to check if your shutdown/reboot/boot code can handle this
+scenario.
+
+"inject_panic"
+--------------
+
+This file is write only and you need to write the delay between the detected
+start of a transmission and the induced Kernel panic (in µs, maximum is 100ms).
+The calling process will then sleep and wait for the next bus clock. The
+process is interruptible, though.
+
+Start of a transfer is detected by waiting for SCL going down by the master
+under test.  A good starting point for using this fault injector is:
+
+# echo 0 > inject_panic &
+# i2cget -y <bus_to_test> <some_address>
+
+Note that there doesn't need to be a device listening to the address you are
+using. Results may vary depending on that, though.

MAINTAINERS

···
 S:	Maintained
 F:	Documentation/devicetree/bindings/eeprom/at24.txt
 F:	drivers/misc/eeprom/at24.c
-F:	include/linux/platform_data/at24.h
 
 ATA OVER ETHERNET (AOE) DRIVER
 M:	"Ed L. Cashin" <[e-mail]>

arch/arm/mach-omap1/board-nokia770.c

···
 #include <linux/clkdev.h>
 #include <linux/irq.h>
 #include <linux/gpio.h>
+#include <linux/gpio/machine.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/mutex.h>
···
 #include <linux/platform_data/keypad-omap.h>
 #include <linux/platform_data/lcd-mipid.h>
 #include <linux/platform_data/gpio-omap.h>
-#include <linux/platform_data/i2c-cbus-gpio.h>
 
 #include <asm/mach-types.h>
 #include <asm/mach/arch.h>
···
 #endif
 
 #if IS_ENABLED(CONFIG_I2C_CBUS_GPIO)
-static struct i2c_cbus_platform_data nokia770_cbus_data = {
-	.clk_gpio = OMAP_MPUIO(9),
-	.dat_gpio = OMAP_MPUIO(10),
-	.sel_gpio = OMAP_MPUIO(11),
+static struct gpiod_lookup_table nokia770_cbus_gpio_table = {
+	.dev_id = "i2c-cbus-gpio.2",
+	.table = {
+		GPIO_LOOKUP_IDX("mpuio", 9, NULL, 0, 0), /* clk */
+		GPIO_LOOKUP_IDX("mpuio", 10, NULL, 1, 0), /* dat */
+		GPIO_LOOKUP_IDX("mpuio", 11, NULL, 2, 0), /* sel */
+		{ },
+	},
 };
 
 static struct platform_device nokia770_cbus_device = {
 	.name   = "i2c-cbus-gpio",
 	.id     = 2,
-	.dev    = {
-		.platform_data = &nokia770_cbus_data,
-	},
 };
 
 static struct i2c_board_info nokia770_i2c_board_info_2[] __initdata = {
···
 	nokia770_i2c_board_info_2[1].irq = gpio_to_irq(tahvo_irq_gpio);
 	i2c_register_board_info(2, nokia770_i2c_board_info_2,
 				ARRAY_SIZE(nokia770_i2c_board_info_2));
+	gpiod_add_lookup_table(&nokia770_cbus_gpio_table);
 	platform_device_register(&nokia770_cbus_device);
 }
 #else /* CONFIG_I2C_CBUS_GPIO */

drivers/i2c/algos/i2c-algo-bit.c

···
-/* -------------------------------------------------------------------------
- * i2c-algo-bit.c i2c driver algorithms for bit-shift adapters
- * -------------------------------------------------------------------------
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * i2c-algo-bit.c: i2c driver algorithms for bit-shift adapters
+ *
  *   Copyright (C) 1995-2000 Simon G. Vogl
-
-    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.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
- * ------------------------------------------------------------------------- */
-
-/* With some changes from Frodo Looijaard <[e-mail]>, Kyösti Mälkki
-   <[e-mail]> and Jean Delvare <[e-mail]> */
+ *
+ * With some changes from Frodo Looijaard <[e-mail]>, Kyösti Mälkki
+ * <[e-mail]> and Jean Delvare <[e-mail]>
+ */
 
 #include <linux/kernel.h>
 #include <linux/module.h>

drivers/i2c/busses/i2c-aspeed.c

···
 
 enum aspeed_i2c_master_state {
 	ASPEED_I2C_MASTER_INACTIVE,
+	ASPEED_I2C_MASTER_PENDING,
 	ASPEED_I2C_MASTER_START,
 	ASPEED_I2C_MASTER_TX_FIRST,
 	ASPEED_I2C_MASTER_TX,
···
 };
 
 enum aspeed_i2c_slave_state {
-	ASPEED_I2C_SLAVE_STOP,
+	ASPEED_I2C_SLAVE_INACTIVE,
 	ASPEED_I2C_SLAVE_START,
 	ASPEED_I2C_SLAVE_READ_REQUESTED,
 	ASPEED_I2C_SLAVE_READ_PROCESSED,
 	ASPEED_I2C_SLAVE_WRITE_REQUESTED,
 	ASPEED_I2C_SLAVE_WRITE_RECEIVED,
+	ASPEED_I2C_SLAVE_STOP,
 };
 
 struct aspeed_i2c_bus {
···
 	int				cmd_err;
 	/* Protected only by i2c_lock_bus */
 	int				master_xfer_result;
+	/* Multi-master */
+	bool				multi_master;
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
 	struct i2c_client		*slave;
 	enum aspeed_i2c_slave_state	slave_state;
···
 	}
 
 	/* Slave is not currently active, irq was for someone else. */
-	if (bus->slave_state == ASPEED_I2C_SLAVE_STOP)
+	if (bus->slave_state == ASPEED_I2C_SLAVE_INACTIVE)
 		return irq_handled;
 
 	dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n",
···
 		irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP;
 		bus->slave_state = ASPEED_I2C_SLAVE_STOP;
 	}
-	if (irq_status & ASPEED_I2CD_INTR_TX_NAK) {
+	if (irq_status & ASPEED_I2CD_INTR_TX_NAK &&
+	    bus->slave_state == ASPEED_I2C_SLAVE_READ_PROCESSED) {
 		irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
 		bus->slave_state = ASPEED_I2C_SLAVE_STOP;
 	}
-	if (irq_status & ASPEED_I2CD_INTR_TX_ACK)
-		irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
 
 	switch (bus->slave_state) {
 	case ASPEED_I2C_SLAVE_READ_REQUESTED:
-		if (irq_status & ASPEED_I2CD_INTR_TX_ACK)
+		if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_ACK))
 			dev_err(bus->dev, "Unexpected ACK on read request.\n");
 		bus->slave_state = ASPEED_I2C_SLAVE_READ_PROCESSED;
 		i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value);
···
 		writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG);
 		break;
 	case ASPEED_I2C_SLAVE_READ_PROCESSED:
-		if (!(irq_status & ASPEED_I2CD_INTR_TX_ACK))
+		if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) {
 			dev_err(bus->dev,
 				"Expected ACK after processed read.\n");
+			break;
+		}
+		irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
 		i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value);
 		writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG);
 		writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG);
···
 		break;
 	case ASPEED_I2C_SLAVE_STOP:
 		i2c_slave_event(slave, I2C_SLAVE_STOP, &value);
+		bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
+		break;
+	case ASPEED_I2C_SLAVE_START:
+		/* Slave was just started. Waiting for the next event. */;
 		break;
 	default:
-		dev_err(bus->dev, "unhandled slave_state: %d\n",
+		dev_err(bus->dev, "unknown slave_state: %d\n",
 			bus->slave_state);
+		bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
 		break;
 	}
 
···
 	u8 slave_addr = i2c_8bit_addr_from_msg(msg);
 
 	bus->master_state = ASPEED_I2C_MASTER_START;
+
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+	/*
+	 * If it's requested in the middle of a slave session, set the master
+	 * state to 'pending' then H/W will continue handling this master
+	 * command when the bus comes back to the idle state.
+	 */
+	if (bus->slave_state != ASPEED_I2C_SLAVE_INACTIVE)
+		bus->master_state = ASPEED_I2C_MASTER_PENDING;
+#endif /* CONFIG_I2C_SLAVE */
+
 	bus->buf_index = 0;
 
 	if (msg->flags & I2C_M_RD) {
···
 		bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
 		irq_handled |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE;
 		goto out_complete;
-	} else {
-		/* Master is not currently active, irq was for someone else. */
-		if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE)
-			goto out_no_complete;
 	}
 
 	/*
···
 	if (ret) {
 		dev_dbg(bus->dev, "received error interrupt: 0x%08x\n",
 			irq_status);
-		bus->cmd_err = ret;
-		bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
 		irq_handled |= (irq_status & ASPEED_I2CD_INTR_MASTER_ERRORS);
-		goto out_complete;
+		if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) {
+			bus->cmd_err = ret;
+			bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
+			goto out_complete;
+		}
 	}
+
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+	/*
+	 * A pending master command will be started by H/W when the bus comes
+	 * back to idle state after completing a slave operation so change the
+	 * master state from 'pending' to 'start' at here if slave is inactive.
+	 */
+	if (bus->master_state == ASPEED_I2C_MASTER_PENDING) {
+		if (bus->slave_state != ASPEED_I2C_SLAVE_INACTIVE)
+			goto out_no_complete;
+
+		bus->master_state = ASPEED_I2C_MASTER_START;
+	}
+#endif /* CONFIG_I2C_SLAVE */
+
+	/* Master is not currently active, irq was for someone else. */
+	if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE ||
+	    bus->master_state == ASPEED_I2C_MASTER_PENDING)
+		goto out_no_complete;
 
 	/* We are in an invalid state; reset bus to a known state. */
 	if (!bus->msgs) {
···
 	 * then update the state and handle the new state below.
 	 */
 	if (bus->master_state == ASPEED_I2C_MASTER_START) {
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+		/*
+		 * If a peer master starts a xfer immediately after it queues a
+		 * master command, change its state to 'pending' then H/W will
+		 * continue the queued master xfer just after completing the
+		 * slave mode session.
+		 */
+		if (unlikely(irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH)) {
+			bus->master_state = ASPEED_I2C_MASTER_PENDING;
+			dev_dbg(bus->dev,
+				"master goes pending due to a slave start\n");
+			goto out_no_complete;
+		}
+#endif /* CONFIG_I2C_SLAVE */
 		if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) {
 			if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_NAK))) {
 				bus->cmd_err = -ENXIO;
···
 	 * interrupt bits. Each case needs to be handled using corresponding
 	 * handlers depending on the current state.
 	 */
-	if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) {
+	if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE &&
+	    bus->master_state != ASPEED_I2C_MASTER_PENDING) {
 		irq_handled = aspeed_i2c_master_irq(bus, irq_remaining);
 		irq_remaining &= ~irq_handled;
 		if (irq_remaining)
···
 {
 	struct aspeed_i2c_bus *bus = i2c_get_adapdata(adap);
 	unsigned long time_left, flags;
-	int ret = 0;
 
 	spin_lock_irqsave(&bus->lock, flags);
 	bus->cmd_err = 0;
 
-	/* If bus is busy, attempt recovery. We assume a single master
-	 * environment.
-	 */
-	if (readl(bus->base + ASPEED_I2C_CMD_REG) & ASPEED_I2CD_BUS_BUSY_STS) {
+	/* If bus is busy in a single master environment, attempt recovery. */
+	if (!bus->multi_master &&
+	    (readl(bus->base + ASPEED_I2C_CMD_REG) &
+	     ASPEED_I2CD_BUS_BUSY_STS)) {
+		int ret;
+
 		spin_unlock_irqrestore(&bus->lock, flags);
 		ret = aspeed_i2c_recover_bus(bus);
 		if (ret)
···
 	time_left = wait_for_completion_timeout(&bus->cmd_complete,
 						bus->adap.timeout);
 
-	if (time_left == 0)
+	if (time_left == 0) {
+		/*
+		 * If timed out and bus is still busy in a multi master
+		 * environment, attempt recovery at here.
+		 */
+		if (bus->multi_master &&
+		    (readl(bus->base + ASPEED_I2C_CMD_REG) &
+		     ASPEED_I2CD_BUS_BUSY_STS))
+			aspeed_i2c_recover_bus(bus);
+
 		return -ETIMEDOUT;
-	else
-		return bus->master_xfer_result;
+	}
+
+	return bus->master_xfer_result;
 }
 
 static u32 aspeed_i2c_functionality(struct i2c_adapter *adap)
···
 	__aspeed_i2c_reg_slave(bus, client->addr);
 
 	bus->slave = client;
-	bus->slave_state = ASPEED_I2C_SLAVE_STOP;
+	bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
 	spin_unlock_irqrestore(&bus->lock, flags);
 
 	return 0;
···
 	if (ret < 0)
 		return ret;
 
-	if (!of_property_read_bool(pdev->dev.of_node, "multi-master"))
+	if (of_property_read_bool(pdev->dev.of_node, "multi-master"))
+		bus->multi_master = true;
+	else
 		fun_ctrl_reg |= ASPEED_I2CD_MULTI_MASTER_DIS;
 
 	/* Enable Master Mode */
···
 	init_completion(&bus->cmd_complete);
 	bus->adap.owner = THIS_MODULE;
 	bus->adap.retries = 0;
-	bus->adap.timeout = 5 * HZ;
 	bus->adap.algo = &aspeed_i2c_algo;
 	bus->adap.dev.parent = &pdev->dev;
 	bus->adap.dev.of_node = pdev->dev.of_node;

drivers/i2c/busses/i2c-brcmstb.c

···
 	struct bsc_regs *bsc_regmap;
 	struct i2c_adapter adapter;
 	struct completion done;
-	bool is_suspended;
 	u32 clk_freq_hz;
 	int data_regsz;
 };
···
 	int xfersz = brcmstb_i2c_get_xfersz(dev);
 	u32 cond, cond_per_msg;
 
-	if (dev->is_suspended)
-		return -EBUSY;
-
 	/* Loop through all messages */
 	for (i = 0; i < num; i++) {
 		pmsg = &msgs[i];
···
 {
 	struct brcmstb_i2c_dev *i2c_dev = dev_get_drvdata(dev);
 
-	i2c_lock_bus(&i2c_dev->adapter, I2C_LOCK_ROOT_ADAPTER);
-	i2c_dev->is_suspended = true;
-	i2c_unlock_bus(&i2c_dev->adapter, I2C_LOCK_ROOT_ADAPTER);
-
+	i2c_mark_adapter_suspended(&i2c_dev->adapter);
 	return 0;
 }
 
···
 {
 	struct brcmstb_i2c_dev *i2c_dev = dev_get_drvdata(dev);
 
-	i2c_lock_bus(&i2c_dev->adapter, I2C_LOCK_ROOT_ADAPTER);
 	brcmstb_i2c_set_bsc_reg_defaults(i2c_dev);
-	i2c_dev->is_suspended = false;
-	i2c_unlock_bus(&i2c_dev->adapter, I2C_LOCK_ROOT_ADAPTER);
+	i2c_mark_adapter_resumed(&i2c_dev->adapter);
 
 	return 0;
 }

drivers/i2c/busses/i2c-cbus-gpio.c

···
 
 #include <linux/io.h>
 #include <linux/i2c.h>
-#include <linux/gpio.h>
 #include <linux/slab.h>
 #include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
-#include <linux/of_gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
-#include <linux/platform_data/i2c-cbus-gpio.h>
 
 /*
  * Bit counts are derived from Nokia implementation. These should be checked
···
 struct cbus_host {
 	spinlock_t	lock;		/* host lock */
 	struct device	*dev;
-	int		clk_gpio;
-	int		dat_gpio;
-	int		sel_gpio;
+	struct gpio_desc *clk;
+	struct gpio_desc *dat;
+	struct gpio_desc *sel;
 };
 
 /**
···
  */
 static void cbus_send_bit(struct cbus_host *host, unsigned bit)
 {
-	gpio_set_value(host->dat_gpio, bit ? 1 : 0);
-	gpio_set_value(host->clk_gpio, 1);
-	gpio_set_value(host->clk_gpio, 0);
+	gpiod_set_value(host->dat, bit ? 1 : 0);
+	gpiod_set_value(host->clk, 1);
+	gpiod_set_value(host->clk, 0);
 }
 
 /**
···
 {
 	int ret;
 
-	gpio_set_value(host->clk_gpio, 1);
-	ret = gpio_get_value(host->dat_gpio);
-	gpio_set_value(host->clk_gpio, 0);
+	gpiod_set_value(host->clk, 1);
+	ret = gpiod_get_value(host->dat);
+	gpiod_set_value(host->clk, 0);
 	return ret;
 }
 
···
 	spin_lock_irqsave(&host->lock, flags);
 
 	/* Reset state and start of transfer, SEL stays down during transfer */
-	gpio_set_value(host->sel_gpio, 0);
+	gpiod_set_value(host->sel, 0);
 
 	/* Set the DAT pin to output */
-	gpio_direction_output(host->dat_gpio, 1);
+	gpiod_direction_output(host->dat, 1);
 
 	/* Send the device address */
 	cbus_send_data(host, dev, CBUS_ADDR_BITS);
···
 		cbus_send_data(host, data, 16);
 		ret = 0;
 	} else {
-		ret = gpio_direction_input(host->dat_gpio);
+		ret = gpiod_direction_input(host->dat);
 		if (ret) {
 			dev_dbg(host->dev, "failed setting direction\n");
 			goto out;
 		}
-		gpio_set_value(host->clk_gpio, 1);
+		gpiod_set_value(host->clk, 1);
 
 		ret = cbus_receive_word(host);
 		if (ret < 0) {
···
 	}
 
 	/* Indicate end of transfer, SEL goes up until next transfer */
-	gpio_set_value(host->sel_gpio, 1);
-	gpio_set_value(host->clk_gpio, 1);
-	gpio_set_value(host->clk_gpio, 0);
+	gpiod_set_value(host->sel, 1);
+	gpiod_set_value(host->clk, 1);
+	gpiod_set_value(host->clk, 0);
 
 out:
 	spin_unlock_irqrestore(&host->lock, flags);
···
 {
 	struct i2c_adapter *adapter;
 	struct cbus_host *chost;
-	int ret;
 
 	adapter = devm_kzalloc(&pdev->dev, sizeof(struct i2c_adapter),
 			       GFP_KERNEL);
···
 	if (!chost)
 		return -ENOMEM;
 
-	if (pdev->dev.of_node) {
-		struct device_node *dnode = pdev->dev.of_node;
-		if (of_gpio_count(dnode) != 3)
-			return -ENODEV;
-		chost->clk_gpio = of_get_gpio(dnode, 0);
-		chost->dat_gpio = of_get_gpio(dnode, 1);
-		chost->sel_gpio = of_get_gpio(dnode, 2);
-	} else if (dev_get_platdata(&pdev->dev)) {
-		struct i2c_cbus_platform_data *pdata =
-			dev_get_platdata(&pdev->dev);
-		chost->clk_gpio = pdata->clk_gpio;
-		chost->dat_gpio = pdata->dat_gpio;
-		chost->sel_gpio = pdata->sel_gpio;
-	} else {
+	if (gpiod_count(&pdev->dev, NULL) != 3)
 		return -ENODEV;
-	}
+	chost->clk = devm_gpiod_get_index(&pdev->dev, NULL, 0, GPIOD_OUT_LOW);
+	if (IS_ERR(chost->clk))
+		return PTR_ERR(chost->clk);
+	chost->dat = devm_gpiod_get_index(&pdev->dev, NULL, 1, GPIOD_IN);
+	if (IS_ERR(chost->dat))
+		return PTR_ERR(chost->dat);
+	chost->sel = devm_gpiod_get_index(&pdev->dev, NULL, 2, GPIOD_OUT_HIGH);
+	if (IS_ERR(chost->sel))
+		return PTR_ERR(chost->sel);
+	gpiod_set_consumer_name(chost->clk, "CBUS clk");
+	gpiod_set_consumer_name(chost->dat, "CBUS dat");
+	gpiod_set_consumer_name(chost->sel, "CBUS sel");
 
 	adapter->owner		= THIS_MODULE;
 	adapter->class		= I2C_CLASS_HWMON;
···
 
 	spin_lock_init(&chost->lock);
 	chost->dev = &pdev->dev;
-
-	ret = devm_gpio_request_one(&pdev->dev, chost->clk_gpio,
-				    GPIOF_OUT_INIT_LOW, "CBUS clk");
-	if (ret)
-		return ret;
-
-	ret = devm_gpio_request_one(&pdev->dev, chost->dat_gpio, GPIOF_IN,
-				    "CBUS data");
-	if (ret)
-		return ret;
-
-	ret = devm_gpio_request_one(&pdev->dev, chost->sel_gpio,
-				    GPIOF_OUT_INIT_HIGH, "CBUS sel");
-	if (ret)
-		return ret;
 
 	i2c_set_adapdata(adapter, chost);
 	platform_set_drvdata(pdev, adapter);

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

···
  * @disable_int: function to disable all interrupts
  * @init: function to initialize the I2C hardware
  * @mode: operation mode - DW_IC_MASTER or DW_IC_SLAVE
+ * @suspended: set to true if the controller is suspended
  *
  * HCNT and LCNT parameters can be used if the platform knows more accurate
  * values than the one computed based only on the input clock frequency.
···
 	int			(*set_sda_hold_time)(struct dw_i2c_dev *dev);
 	int			mode;
 	struct i2c_bus_recovery_info rinfo;
+	bool			suspended;
 };
 
 #define ACCESS_SWAP		0x00000001

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

···
 
 	pm_runtime_get_sync(dev->dev);
 
+	if (dev->suspended) {
+		dev_err(dev->dev, "Error %s call while suspended\n", __func__);
+		ret = -ESHUTDOWN;
+		goto done_nolock;
+	}
+
 	reinit_completion(&dev->cmd_complete);
 	dev->msgs = msgs;
 	dev->msgs_num = num;

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

···
 	struct pci_dev *pdev = to_pci_dev(dev);
 	struct dw_i2c_dev *i_dev = pci_get_drvdata(pdev);
 
+	i_dev->suspended = true;
 	i_dev->disable(i_dev);
 
 	return 0;
···
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
 	struct dw_i2c_dev *i_dev = pci_get_drvdata(pdev);
+	int ret;
 
-	return i_dev->init(i_dev);
+	ret = i_dev->init(i_dev);
+	i_dev->suspended = false;
+
+	return ret;
 }
 #endif
 

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

···
 {
 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 
+	i_dev->suspended = true;
+
 	if (i_dev->shared_with_punit)
 		return 0;
 
···
 		i2c_dw_prepare_clk(i_dev, true);
 
 	i_dev->init(i_dev);
+	i_dev->suspended = false;
 
 	return 0;
 }

drivers/i2c/busses/i2c-exynos5.c

···
 
 struct exynos5_i2c {
 	struct i2c_adapter	adap;
-	unsigned int		suspended:1;
 
 	struct i2c_msg		*msg;
 	struct completion	msg_complete;
···
 	struct exynos5_i2c *i2c = adap->algo_data;
 	int i, ret;
 
-	if (i2c->suspended) {
-		dev_err(i2c->dev, "HS-I2C is not initialized.\n");
-		return -EIO;
-	}
-
 	ret = clk_enable(i2c->clk);
 	if (ret)
 		return ret;
···
 {
 	struct exynos5_i2c *i2c = dev_get_drvdata(dev);
 
-	i2c->suspended = 1;
-
+	i2c_mark_adapter_suspended(&i2c->adap);
 	clk_unprepare(i2c->clk);
 
 	return 0;
···
 
 	exynos5_i2c_init(i2c);
 	clk_disable(i2c->clk);
-	i2c->suspended = 0;
+	i2c_mark_adapter_resumed(&i2c->adap);
 
 	return 0;
 }

drivers/i2c/busses/i2c-gpio.c

···
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
+#include <linux/completion.h>
 #include <linux/debugfs.h>
 #include <linux/delay.h>
-#include <linux/i2c.h>
-#include <linux/i2c-algo-bit.h>
-#include <linux/platform_data/i2c-gpio.h>
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/platform_device.h>
 #include <linux/gpio/consumer.h>
+#include <linux/i2c-algo-bit.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
 #include <linux/of.h>
+#include <linux/platform_data/i2c-gpio.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
 
 struct i2c_gpio_private_data {
 	struct gpio_desc *sda;
···
 	struct i2c_gpio_platform_data pdata;
 #ifdef CONFIG_I2C_GPIO_FAULT_INJECTOR
 	struct dentry *debug_dir;
+	/* these must be protected by bus lock */
+	struct completion scl_irq_completion;
+	u64 scl_irq_data;
 #endif
 };
 
···
 }
 DEFINE_DEBUGFS_ATTRIBUTE(fops_incomplete_write_byte, NULL, fops_incomplete_write_byte_set, "%llu\n");
 
+static int i2c_gpio_fi_act_on_scl_irq(struct i2c_gpio_private_data *priv,
+				       irqreturn_t handler(int, void*))
+{
+	int ret, irq = gpiod_to_irq(priv->scl);
+
+	if (irq < 0)
+		return irq;
+
+	i2c_lock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER);
+
+	ret = gpiod_direction_input(priv->scl);
+	if (ret)
+		goto unlock;
+
+	reinit_completion(&priv->scl_irq_completion);
+
+	ret = request_irq(irq, handler, IRQF_TRIGGER_FALLING,
+			  "i2c_gpio_fault_injector_scl_irq", priv);
+	if (ret)
+		goto output;
+
+	wait_for_completion_interruptible(&priv->scl_irq_completion);
+
+	free_irq(irq, priv);
+ output:
+	ret = gpiod_direction_output(priv->scl, 1) ?: ret;
+ unlock:
+	i2c_unlock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER);
+
+	return ret;
+}
+
+static irqreturn_t lose_arbitration_irq(int irq, void *dev_id)
+{
+	struct i2c_gpio_private_data *priv = dev_id;
+
+	setsda(&priv->bit_data, 0);
+	udelay(priv->scl_irq_data);
+	setsda(&priv->bit_data, 1);
+
+	complete(&priv->scl_irq_completion);
+
+	return IRQ_HANDLED;
+}
+
+static int fops_lose_arbitration_set(void *data, u64 duration)
+{
+	struct i2c_gpio_private_data *priv = data;
+
+	if (duration > 100 * 1000)
+		return -EINVAL;
+
+	priv->scl_irq_data = duration;
+	/*
+	 * Interrupt on falling SCL. This ensures that the master under test has
+	 * really started the transfer. Interrupt on falling SDA did only
+	 * exercise 'bus busy' detection on some HW but not 'arbitration lost'.
+	 * Note that the interrupt latency may cause the first bits to be
+	 * transmitted correctly.
+	 */
+	return i2c_gpio_fi_act_on_scl_irq(priv, lose_arbitration_irq);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(fops_lose_arbitration, NULL, fops_lose_arbitration_set, "%llu\n");
+
+static irqreturn_t inject_panic_irq(int irq, void *dev_id)
+{
+	struct i2c_gpio_private_data *priv = dev_id;
+
+	udelay(priv->scl_irq_data);
+	panic("I2C fault injector induced panic");
+
+	return IRQ_HANDLED;
+}
+
+static int fops_inject_panic_set(void *data, u64 duration)
+{
+	struct i2c_gpio_private_data *priv = data;
+
+	if (duration > 100 * 1000)
+		return -EINVAL;
+
+	priv->scl_irq_data = duration;
+	/*
+	 * Interrupt on falling SCL. This ensures that the master under test has
+	 * really started the transfer.
+	 */
+	return i2c_gpio_fi_act_on_scl_irq(priv, inject_panic_irq);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(fops_inject_panic, NULL, fops_inject_panic_set, "%llu\n");
+
 static void i2c_gpio_fault_injector_init(struct platform_device *pdev)
 {
 	struct i2c_gpio_private_data *priv = platform_get_drvdata(pdev);
···
 	if (!priv->debug_dir)
 		return;
 
-	debugfs_create_file_unsafe("scl", 0600, priv->debug_dir, priv, &fops_scl);
-	debugfs_create_file_unsafe("sda", 0600, priv->debug_dir, priv, &fops_sda);
+	init_completion(&priv->scl_irq_completion);
+
 	debugfs_create_file_unsafe("incomplete_address_phase", 0200, priv->debug_dir,
 				   priv, &fops_incomplete_addr_phase);
 	debugfs_create_file_unsafe("incomplete_write_byte", 0200, priv->debug_dir,
 				   priv, &fops_incomplete_write_byte);
+	if (priv->bit_data.getscl) {
+		debugfs_create_file_unsafe("inject_panic", 0200, priv->debug_dir,
+					   priv, &fops_inject_panic);
+		debugfs_create_file_unsafe("lose_arbitration", 0200, priv->debug_dir,
+					   priv, &fops_lose_arbitration);
+	}
+	debugfs_create_file_unsafe("scl", 0600, priv->debug_dir, priv, &fops_scl);
+	debugfs_create_file_unsafe("sda", 0600, priv->debug_dir, priv, &fops_sda);
 }
 
 static void i2c_gpio_fault_injector_exit(struct platform_device *pdev)
···
 
 	/*
 	 * First get the GPIO pins; if it fails, we'll defer the probe.
-	 * If the SDA line is marked from platform data or device tree as
-	 * "open drain" it means something outside of our control is making
-	 * this line being handled as open drain, and we should just handle
-	 * it as any other output. Else we enforce open drain as this is
-	 * required for an I2C bus.
+	 * If the SCL/SDA lines are marked "open drain" by platform data or
+	 * device tree then this means that something outside of our control is
+	 * marking these lines to be handled as open drain, and we should just
+	 * handle them as we handle any other output. Else we enforce open
+	 * drain as this is required for an I2C bus.
 	 */
 	if (pdata->sda_is_open_drain)
 		gflags = GPIOD_OUT_HIGH;
···
 	if (IS_ERR(priv->sda))
 		return PTR_ERR(priv->sda);
 
-	/*
-	 * If the SCL line is marked from platform data or device tree as
-	 * "open drain" it means something outside of our control is making
-	 * this line being handled as open drain, and we should just handle
-	 * it as any other output. Else we enforce open drain as this is
-	 * required for an I2C bus.
-	 */
 	if (pdata->scl_is_open_drain)
 		gflags = GPIOD_OUT_HIGH;
 	else

drivers/i2c/busses/i2c-imx.c

···
 }
 
 /* Functions for DMA support */
-static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
-						dma_addr_t phy_addr)
+static int i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
+			       dma_addr_t phy_addr)
 {
 	struct imx_i2c_dma *dma;
 	struct dma_slave_config dma_sconfig;
···
 
 	dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
 	if (!dma)
-		return;
+		return -ENOMEM;
 
-	dma->chan_tx = dma_request_slave_channel(dev, "tx");
-	if (!dma->chan_tx) {
-		dev_dbg(dev, "can't request DMA tx channel\n");
+	dma->chan_tx = dma_request_chan(dev, "tx");
+	if (IS_ERR(dma->chan_tx)) {
+		ret = PTR_ERR(dma->chan_tx);
+		if (ret != -ENODEV && ret != -EPROBE_DEFER)
+			dev_err(dev, "can't request DMA tx channel (%d)\n", ret);
 		goto fail_al;
 	}
 
···
 	dma_sconfig.direction = DMA_MEM_TO_DEV;
 	ret = dmaengine_slave_config(dma->chan_tx, &dma_sconfig);
 	if (ret < 0) {
-		dev_dbg(dev, "can't configure tx channel\n");
+		dev_err(dev, "can't configure tx channel (%d)\n", ret);
 		goto fail_tx;
 	}
 
-	dma->chan_rx = dma_request_slave_channel(dev, "rx");
-	if (!dma->chan_rx) {
-		dev_dbg(dev, "can't request DMA rx channel\n");
+	dma->chan_rx = dma_request_chan(dev, "rx");
+	if (IS_ERR(dma->chan_rx)) {
+		ret = PTR_ERR(dma->chan_rx);
+		if (ret != -ENODEV && ret != -EPROBE_DEFER)
+			dev_err(dev, "can't request DMA rx channel (%d)\n", ret);
 		goto fail_tx;
 	}
 
···
 	dma_sconfig.direction = DMA_DEV_TO_MEM;
 	ret = dmaengine_slave_config(dma->chan_rx, &dma_sconfig);
 	if (ret < 0) {
-		dev_dbg(dev, "can't configure rx channel\n");
+		dev_err(dev, "can't configure rx channel (%d)\n", ret);
 		goto fail_rx;
 	}
 
···
 	dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n",
 		dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx));
 
-	return;
+	return 0;
 
 fail_rx:
 	dma_release_channel(dma->chan_rx);
···
 	dma_release_channel(dma->chan_tx);
 fail_al:
 	devm_kfree(dev, dma);
-	dev_info(dev, "can't use DMA, using PIO instead.\n");
+	/* return successfully if there is no dma support */
+	return ret == -ENODEV ? 0 : ret;
 }
 
 static void i2c_imx_dma_callback(void *arg)
···
 	dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res);
 	dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
 		i2c_imx->adapter.name);
-	dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
 
 	/* Init DMA config if supported */
-	i2c_imx_dma_request(i2c_imx, phy_addr);
+	ret = i2c_imx_dma_request(i2c_imx, phy_addr);
+	if (ret < 0)
+		goto clk_notifier_unregister;
 
+	dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
 	return 0;   /* Return OK */
 
 clk_notifier_unregister:

drivers/i2c/busses/i2c-iop3xx.c

···
 	new_adapter->owner = THIS_MODULE;
 	new_adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
 	new_adapter->dev.parent = &pdev->dev;
+	new_adapter->dev.of_node = pdev->dev.of_node;
 	new_adapter->nr = pdev->id;
 
 	/*
···
 	return ret;
 }
 
+static const struct of_device_id i2c_iop3xx_match[] = {
+	{ .compatible = "intel,iop3xx-i2c", },
+	{ .compatible = "intel,ixp4xx-i2c", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, i2c_iop3xx_match);
 
 static struct platform_driver iop3xx_i2c_driver = {
 	.probe		= iop3xx_i2c_probe,
 	.remove		= iop3xx_i2c_remove,
 	.driver		= {
 		.name	= "IOP3xx-I2C",
+		.of_match_table = i2c_iop3xx_match,
 	},
 };
 

drivers/i2c/busses/i2c-mt65xx.c

···
 
 	control_reg = readw(i2c->base + OFFSET_CONTROL) &
 			~(I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS);
-	if ((i2c->speed_hz > 400000) || (left_num >= 1))
+	if ((i2c->speed_hz > MAX_FS_MODE_SPEED) || (left_num >= 1))
 		control_reg |= I2C_CONTROL_RS;
 
 	if (i2c->op == I2C_MASTER_WRRD)
···
 	writew(control_reg, i2c->base + OFFSET_CONTROL);
 
 	/* set start condition */
-	if (i2c->speed_hz <= 100000)
+	if (i2c->speed_hz <= I2C_DEFAULT_SPEED)
 		writew(I2C_ST_START_CON, i2c->base + OFFSET_EXT_CONF);
 	else
 		writew(I2C_FS_START_CON, i2c->base + OFFSET_EXT_CONF);
···
 		mtk_i2c_init_hw(i2c);
 		return -ETIMEDOUT;
 	}
-
-	completion_done(&i2c->msg_complete);
 
 	if (i2c->irq_stat & (I2C_HS_NACKERR | I2C_ACKERR)) {
 		dev_dbg(i2c->dev, "addr: %x, transfer ACK error\n", msgs->addr);

drivers/i2c/busses/i2c-ocores.c

···
+// SPDX-License-Identifier: GPL-2.0
 /*
  * i2c-ocores.c: I2C bus driver for OpenCores I2C controller
  * (https://opencores.org/project/i2c/overview)
···
  *
  * Support for the GRLIB port of the controller by
  * Andreas Larsson <[e-mail]>
- *
- * This file is licensed under the terms of the GNU General Public License
- * version 2.  This program is licensed "as is" without any warranty of any
- * kind, whether express or implied.
  */
 
 #include <linux/clk.h>
+#include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
···
 #include <linux/slab.h>
 #include <linux/io.h>
 #include <linux/log2.h>
+#include <linux/spinlock.h>
+#include <linux/jiffies.h>
 
+#define OCORES_FLAG_POLL BIT(0)
+
+/*
+ * 'process_lock' exists because ocores_process() and ocores_process_timeout()
+ * can't run in parallel.
+ */
 struct ocores_i2c {
 	void __iomem *base;
+	int iobase;
 	u32 reg_shift;
 	u32 reg_io_width;
+	unsigned long flags;
 	wait_queue_head_t wait;
 	struct i2c_adapter adap;
 	struct i2c_msg *msg;
 	int pos;
 	int nmsgs;
 	int state; /* see STATE_ */
+	spinlock_t process_lock;
 	struct clk *clk;
 	int ip_clock_khz;
 	int bus_clock_khz;
···
 	return ioread32be(i2c->base + (reg << i2c->reg_shift));
 }
 
+static void oc_setreg_io_8(struct ocores_i2c *i2c, int reg, u8 value)
+{
+	outb(value, i2c->iobase + reg);
+}
+
+static inline u8 oc_getreg_io_8(struct ocores_i2c *i2c, int reg)
+{
+	return inb(i2c->iobase + reg);
+}
+
 static inline void oc_setreg(struct ocores_i2c *i2c, int reg, u8 value)
 {
 	i2c->setreg(i2c, reg, value);
···
 	return i2c->getreg(i2c, reg);
 }
 
-static void ocores_process(struct ocores_i2c *i2c)
+static void ocores_process(struct ocores_i2c *i2c, u8 stat)
 {
 	struct i2c_msg *msg = i2c->msg;
-	u8 stat = oc_getreg(i2c, OCI2C_STATUS);
+	unsigned long flags;
+
+	/*
+	 * If we spin here is because we are in timeout, so we are going
+	 * to be in STATE_ERROR. See ocores_process_timeout()
+	 */
+	spin_lock_irqsave(&i2c->process_lock, flags);
 
 	if ((i2c->state == STATE_DONE) || (i2c->state == STATE_ERROR)) {
 		/* stop has been sent */
 		oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_IACK);
 		wake_up(&i2c->wait);
-		return;
+		goto out;
 	}
 
 	/* error? */
 	if (stat & OCI2C_STAT_ARBLOST) {
 		i2c->state = STATE_ERROR;
 		oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_STOP);
-		return;
+		goto out;
 	}
 
 	if ((i2c->state == STATE_START) || (i2c->state == STATE_WRITE)) {
···
 		if (stat & OCI2C_STAT_NACK) {
 			i2c->state = STATE_ERROR;
 			oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_STOP);
-			return;
+			goto out;
 		}
-	} else
+	} else {
 		msg->buf[i2c->pos++] = oc_getreg(i2c, OCI2C_DATA);
+	}
 
 	/* end of msg? */
 	if (i2c->pos == msg->len) {
···
 				i2c->state = STATE_START;
 
 				oc_setreg(i2c, OCI2C_DATA, addr);
-				oc_setreg(i2c, OCI2C_CMD,  OCI2C_CMD_START);
-				return;
-			} else
-				i2c->state = (msg->flags & I2C_M_RD)
-					? STATE_READ : STATE_WRITE;
+				oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_START);
+				goto out;
+			}
+			i2c->state = (msg->flags & I2C_M_RD)
+				? STATE_READ : STATE_WRITE;
 		} else {
 			i2c->state = STATE_DONE;
 			oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_STOP);
-			return;
+			goto out;
 		}
 	}
 
···
 		oc_setreg(i2c, OCI2C_DATA, msg->buf[i2c->pos++]);
 		oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_WRITE);
 	}
+
+out:
+	spin_unlock_irqrestore(&i2c->process_lock, flags);
 }
 
 static irqreturn_t ocores_isr(int irq, void *dev_id)
 {
 	struct ocores_i2c *i2c = dev_id;
+	u8 stat = oc_getreg(i2c, OCI2C_STATUS);
 
-	ocores_process(i2c);
+	if (!(stat & OCI2C_STAT_IF))
+		return IRQ_NONE;
+
+	ocores_process(i2c, stat);
 
 	return IRQ_HANDLED;
 }
 
-static int ocores_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+/**
+ * Process timeout event
+ * @i2c: ocores I2C device instance
+ */
+static void ocores_process_timeout(struct ocores_i2c *i2c)
 {
-	struct ocores_i2c *i2c = i2c_get_adapdata(adap);
+	unsigned long flags;
+
+	spin_lock_irqsave(&i2c->process_lock, flags);
+	i2c->state = STATE_ERROR;
+	oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_STOP);
+	spin_unlock_irqrestore(&i2c->process_lock, flags);
+}
+
+/**
+ * Wait until something change in a given register
+ * @i2c: ocores I2C device instance
+ * @reg: register to query
+ * @mask: bitmask to apply on register value
+ * @val: expected result
+ * @timeout: timeout in jiffies
+ *
+ * Timeout is necessary to avoid to stay here forever when the chip
+ * does not answer correctly.
+ *
+ * Return: 0 on success, -ETIMEDOUT on timeout
+ */
+static int ocores_wait(struct ocores_i2c *i2c,
+		       int reg, u8 mask, u8 val,
+		       const unsigned long timeout)
+{
+	unsigned long j;
+
+	j = jiffies + timeout;
+	while (1) {
+		u8 status = oc_getreg(i2c, reg);
+
+		if ((status & mask) == val)
+			break;
+
+		if (time_after(jiffies, j))
+			return -ETIMEDOUT;
+	}
+	return 0;
+}
+
+/**
+ * Wait until is possible to process some data
+ * @i2c: ocores I2C device instance
+ *
+ * Used when the device is in polling mode (interrupts disabled).
+ *
+ * Return: 0 on success, -ETIMEDOUT on timeout
+ */
+static int ocores_poll_wait(struct ocores_i2c *i2c)
+{
+	u8 mask;
+	int err;
+
+	if (i2c->state == STATE_DONE || i2c->state == STATE_ERROR) {
+		/* transfer is over */
+		mask = OCI2C_STAT_BUSY;
+	} else {
+		/* on going transfer */
+		mask = OCI2C_STAT_TIP;
+		/*
+		 * We wait for the data to be transferred (8bit),
+		 * then we start polling on the ACK/NACK bit
+		 */
+		udelay((8 * 1000) / i2c->bus_clock_khz);
+	}
+
+	/*
+	 * once we are here we expect to get the expected result immediately
+	 * so if after 1ms we timeout then something is broken.
+	 */
+	err = ocores_wait(i2c, OCI2C_STATUS, mask, 0, msecs_to_jiffies(1));
+	if (err)
+		dev_warn(i2c->adap.dev.parent,
+			 "%s: STATUS timeout, bit 0x%x did not clear in 1ms\n",
+			 __func__, mask);
+	return err;
+}
+
+/**
+ * It handles an IRQ-less transfer
+ * @i2c: ocores I2C device instance
+ *
+ * Even if IRQ are disabled, the I2C OpenCore IP behavior is exactly the same
+ * (only that IRQ are not produced). This means that we can re-use entirely
+ * ocores_isr(), we just add our polling code around it.
+ *
+ * It can run in atomic context
+ */
+static void ocores_process_polling(struct ocores_i2c *i2c)
+{
+	while (1) {
+		irqreturn_t ret;
+		int err;
+
+		err = ocores_poll_wait(i2c);
+		if (err) {
+			i2c->state = STATE_ERROR;
+			break; /* timeout */
+		}
+
+		ret = ocores_isr(-1, i2c);
+		if (ret == IRQ_NONE)
+			break; /* all messages have been transferred */
+	}
+}
+
+static int ocores_xfer_core(struct ocores_i2c *i2c,
+			    struct i2c_msg *msgs, int num,
+			    bool polling)
+{
+	int ret;
+	u8 ctrl;
+
+	ctrl = oc_getreg(i2c, OCI2C_CONTROL);
+	if (polling)
+		oc_setreg(i2c, OCI2C_CONTROL, ctrl & ~OCI2C_CTRL_IEN);
+	else
+		oc_setreg(i2c, OCI2C_CONTROL, ctrl | OCI2C_CTRL_IEN);
 
 	i2c->msg = msgs;
 	i2c->pos = 0;
···
 	oc_setreg(i2c, OCI2C_DATA, i2c_8bit_addr_from_msg(i2c->msg));
 	oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_START);
 
-	if (wait_event_timeout(i2c->wait, (i2c->state == STATE_ERROR) ||
-			       (i2c->state == STATE_DONE), HZ))
-		return (i2c->state == STATE_DONE) ? num : -EIO;
-	else
-		return -ETIMEDOUT;
+	if (polling) {
+		ocores_process_polling(i2c);
+	} else {
+		ret = wait_event_timeout(i2c->wait,
+					 (i2c->state == STATE_ERROR) ||
+					 (i2c->state == STATE_DONE), HZ);
+		if (ret == 0) {
+			ocores_process_timeout(i2c);
+			return -ETIMEDOUT;
+		}
+	}
+
+	return (i2c->state == STATE_DONE) ? num : -EIO;
+}
+
+static int ocores_xfer_polling(struct i2c_adapter *adap,
+			       struct i2c_msg *msgs, int num)
+{
+	return ocores_xfer_core(i2c_get_adapdata(adap), msgs, num, true);
+}
+
+static int ocores_xfer(struct i2c_adapter *adap,
+		       struct i2c_msg *msgs, int num)
+{
+	struct ocores_i2c *i2c = i2c_get_adapdata(adap);
+
+	if (i2c->flags & OCORES_FLAG_POLL)
+		return ocores_xfer_polling(adap, msgs, num);
+	return ocores_xfer_core(i2c, msgs, num, false);
 }
 
 static int ocores_init(struct device *dev, struct ocores_i2c *i2c)
···
 	u8 ctrl = oc_getreg(i2c, OCI2C_CONTROL);
 
 	/* make sure the device is disabled */
-	oc_setreg(i2c, OCI2C_CONTROL, ctrl & ~(OCI2C_CTRL_EN|OCI2C_CTRL_IEN));
+	ctrl &= ~(OCI2C_CTRL_EN | OCI2C_CTRL_IEN);
+	oc_setreg(i2c, OCI2C_CONTROL, ctrl);
 
 	prescale = (i2c->ip_clock_khz / (5 * i2c->bus_clock_khz)) - 1;
 	prescale = clamp(prescale, 0, 0xffff);
···
 
 	/* Init the device */
 	oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_IACK);
-	oc_setreg(i2c, OCI2C_CONTROL, ctrl | OCI2C_CTRL_IEN | OCI2C_CTRL_EN);
+	oc_setreg(i2c, OCI2C_CONTROL, ctrl | OCI2C_CTRL_EN);
 
 	return 0;
 }
···
 MODULE_DEVICE_TABLE(of, ocores_i2c_match);
 
 #ifdef CONFIG_OF
-/* Read and write functions for the GRLIB port of the controller. Registers are
+/*
+ * Read and write functions for the GRLIB port of the controller. Registers are
  * 32-bit big endian and the PRELOW and PREHIGH registers are merged into one
- * register. The subsequent registers has their offset decreased accordingly. */
+ * register. The subsequent registers have their offsets decreased accordingly.
+ */
 static u8 oc_getreg_grlib(struct ocores_i2c *i2c, int reg)
 {
 	u32 rd;
 	int rreg = reg;
+
 	if (reg != OCI2C_PRELOW)
 		rreg--;
 	rd = ioread32be(i2c->base + (rreg << i2c->reg_shift));
···
 {
 	u32 curr, wr;
 	int rreg = reg;
+
 	if (reg != OCI2C_PRELOW)
 		rreg--;
 	if (reg == OCI2C_PRELOW || reg == OCI2C_PREHIGH) {
···
 	return 0;
 }
 #else
-#define ocores_i2c_of_probe(pdev,i2c) -ENODEV
+#define ocores_i2c_of_probe(pdev, i2c) -ENODEV
 #endif
 
 static int ocores_i2c_probe(struct platform_device *pdev)
···
 	int ret;
 	int i;
 
-	irq = platform_get_irq(pdev, 0);
-	if (irq < 0)
-		return irq;
-
 	i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
 	if (!i2c)
 		return -ENOMEM;
 
+	spin_lock_init(&i2c->process_lock);
+
 	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);
+	if (res) {
+		i2c->base = devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(i2c->base))
+			return PTR_ERR(i2c->base);
+	} else {
+		res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+		if (!res)
+			return -EINVAL;
+		i2c->iobase = res->start;
+		if (!devm_request_region(&pdev->dev, res->start,
+					 resource_size(res),
+					 pdev->name)) {
+			dev_err(&pdev->dev, "Can't get I/O resource.\n");
+			return -EBUSY;
+		}
+		i2c->setreg = oc_setreg_io_8;
+		i2c->getreg = oc_getreg_io_8;
+	}
 
 	pdata = dev_get_platdata(&pdev->dev);
 	if (pdata) {
 		i2c->reg_shift = pdata->reg_shift;
 		i2c->reg_io_width = pdata->reg_io_width;
 		i2c->ip_clock_khz = pdata->clock_khz;
-		i2c->bus_clock_khz = 100;
+		if (pdata->bus_khz)
+			i2c->bus_clock_khz = pdata->bus_khz;
+		else
+			i2c->bus_clock_khz = 100;
 	} else {
 		ret = ocores_i2c_of_probe(pdev, i2c);
 		if (ret)
···
 		}
 	}
 
+	init_waitqueue_head(&i2c->wait);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq == -ENXIO) {
+		i2c->flags |= OCORES_FLAG_POLL;
+	} else {
+		if (irq < 0)
+			return irq;
+	}
+
+	if (!(i2c->flags & OCORES_FLAG_POLL)) {
+		ret = devm_request_irq(&pdev->dev, irq, ocores_isr, 0,
+				       pdev->name, i2c);
+		if (ret) {
+			dev_err(&pdev->dev, "Cannot claim IRQ\n");
+			goto err_clk;
+		}
+	}
+
 	ret = ocores_init(&pdev->dev, i2c);
 	if (ret)
 		goto err_clk;
-
-	init_waitqueue_head(&i2c->wait);
-	ret = devm_request_irq(&pdev->dev, irq, ocores_isr, 0,
-			       pdev->name, i2c);
-	if (ret) {
-		dev_err(&pdev->dev, "Cannot claim IRQ\n");
-		goto err_clk;
-	}
 
 	/* hook up driver to tree */
 	platform_set_drvdata(pdev, i2c);
···
 static int ocores_i2c_remove(struct platform_device *pdev)
 {
 	struct ocores_i2c *i2c = platform_get_drvdata(pdev);
+	u8 ctrl = oc_getreg(i2c, OCI2C_CONTROL);
 
 	/* disable i2c logic */
-	oc_setreg(i2c, OCI2C_CONTROL, oc_getreg(i2c, OCI2C_CONTROL)
-		  & ~(OCI2C_CTRL_EN|OCI2C_CTRL_IEN));
+	ctrl &= ~(OCI2C_CTRL_EN | OCI2C_CTRL_IEN);
+	oc_setreg(i2c, OCI2C_CONTROL, ctrl);
 
 	/* remove adapter & data */
 	i2c_del_adapter(&i2c->adap);
···
 	u8 ctrl = oc_getreg(i2c, OCI2C_CONTROL);
 
 	/* make sure the device is disabled */
-	oc_setreg(i2c, OCI2C_CONTROL, ctrl & ~(OCI2C_CTRL_EN|OCI2C_CTRL_IEN));
+	ctrl &= ~(OCI2C_CTRL_EN | OCI2C_CTRL_IEN);
+	oc_setreg(i2c, OCI2C_CONTROL, ctrl);
 
 	if (!IS_ERR(i2c->clk))
 		clk_disable_unprepare(i2c->clk);

drivers/i2c/busses/i2c-rcar.c

···
 /*
  * Driver for the Renesas R-Car I2C unit
  *
- * Copyright (C) 2014-15 Wolfram Sang <[e-mail]>
- * Copyright (C) 2011-2015 Renesas Electronics Corporation
+ * Copyright (C) 2014-19 Wolfram Sang <[e-mail]>
+ * Copyright (C) 2011-2019 Renesas Electronics Corporation
  *
  * Copyright (C) 2012-14 Renesas Solutions Corp.
  * Kuninori Morimoto <[e-mail]>
···
 #define ICSAR	0x1C	/* slave address */
 #define ICMAR	0x20	/* master address */
 #define ICRXTX	0x24	/* data port */
-#define ICDMAER	0x3c	/* DMA enable */
-#define ICFBSCR	0x38	/* first bit setup cycle */
+#define ICFBSCR	0x38	/* first bit setup cycle (Gen3) */
+#define ICDMAER	0x3c	/* DMA enable (Gen3) */
 
 /* ICSCR */
 #define SDBS	(1 << 3)	/* slave data buffer select */
···
 #define TMDMAE	(1 << 0)	/* DMA Master Transmitted Enable */
 
 /* ICFBSCR */
-#define TCYC06	0x04		/*  6*Tcyc delay 1st bit between SDA and SCL */
 #define TCYC17	0x0f		/* 17*Tcyc delay 1st bit between SDA and SCL */
 
 
···
 	rcar_i2c_write(priv, ICMSR, 0);
 	/* start clock */
 	rcar_i2c_write(priv, ICCCR, priv->icccr);
+
+	if (priv->devtype == I2C_RCAR_GEN3)
+		rcar_i2c_write(priv, ICFBSCR, TCYC17);
+
 }
 
 static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv)
···
 	rcar_i2c_prepare_msg(priv);
 }
 
-/*
- *		interrupt functions
- */
 static void rcar_i2c_dma_unmap(struct rcar_i2c_priv *priv)
 {
 	struct dma_chan *chan = priv->dma_direction == DMA_FROM_DEVICE
···
 
 	/* Disable DMA Master Received/Transmitted */
 	rcar_i2c_write(priv, ICDMAER, 0);
-
-	/* Reset default delay */
-	rcar_i2c_write(priv, ICFBSCR, TCYC06);
 
 	dma_unmap_single(chan->device->dev, sg_dma_address(&priv->sg),
 			 sg_dma_len(&priv->sg), priv->dma_direction);
···
 		rcar_i2c_cleanup_dma(priv);
 		return;
 	}
-
-	/* Set delay for DMA operations */
-	rcar_i2c_write(priv, ICFBSCR, TCYC17);
 
 	/* Enable DMA Master Received/Transmitted */
 	if (read)
···
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int rcar_i2c_suspend(struct device *dev)
+{
+	struct rcar_i2c_priv *priv = dev_get_drvdata(dev);
+
+	i2c_mark_adapter_suspended(&priv->adap);
+	return 0;
+}
+
+static int rcar_i2c_resume(struct device *dev)
+{
+	struct rcar_i2c_priv *priv = dev_get_drvdata(dev);
+
+	i2c_mark_adapter_resumed(&priv->adap);
+	return 0;
+}
+
+static const struct dev_pm_ops rcar_i2c_pm_ops = {
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(rcar_i2c_suspend, rcar_i2c_resume)
+};
+
+#define DEV_PM_OPS (&rcar_i2c_pm_ops)
+#else
+#define DEV_PM_OPS NULL
+#endif /* CONFIG_PM_SLEEP */
+
 static struct platform_driver rcar_i2c_driver = {
 	.driver	= {
 		.name	= "i2c-rcar",
 		.of_match_table = rcar_i2c_dt_ids,
+		.pm	= DEV_PM_OPS,
 	},
 	.probe		= rcar_i2c_probe,
 	.remove		= rcar_i2c_remove,

drivers/i2c/busses/i2c-s3c2410.c

···
 struct s3c24xx_i2c {
 	wait_queue_head_t	wait;
 	kernel_ulong_t		quirks;
-	unsigned int		suspended:1;
 
 	struct i2c_msg		*msg;
 	unsigned int		msg_num;
···
 	unsigned long timeout;
 	int ret;
 
-	if (i2c->suspended)
-		return -EIO;
-
 	ret = s3c24xx_i2c_set_master(i2c);
 	if (ret != 0) {
 		dev_err(i2c->dev, "cannot get bus (error %d)\n", ret);
···
 {
 	struct s3c24xx_i2c *i2c = dev_get_drvdata(dev);
 
-	i2c->suspended = 1;
+	i2c_mark_adapter_suspended(&i2c->adap);
 
 	if (!IS_ERR(i2c->sysreg))
 		regmap_read(i2c->sysreg, EXYNOS5_SYS_I2C_CFG, &i2c->sys_i2c_cfg);
···
 		return ret;
 	s3c24xx_i2c_init(i2c);
 	clk_disable(i2c->clk);
-	i2c->suspended = 0;
+	i2c_mark_adapter_resumed(&i2c->adap);
 
 	return 0;
 }

drivers/i2c/busses/i2c-sh_mobile.c

···
 /*
  * SuperH Mobile I2C Controller
  *
- * Copyright (C) 2014 Wolfram Sang <[e-mail]>
- *
+ * Copyright (C) 2014-19 Wolfram Sang <[e-mail]>
  * Copyright (C) 2008 Magnus Damm
  *
  * Portions of the code based on out-of-tree driver i2c-sh7343.c
···
 	return sh_mobile_i2c_check_timing(pd);
 }
 
-static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
-			    enum sh_mobile_i2c_op op, unsigned char data)
+static unsigned char i2c_op(struct sh_mobile_i2c_data *pd, enum sh_mobile_i2c_op op)
 {
 	unsigned char ret = 0;
 	unsigned long flags;
 
-	dev_dbg(pd->dev, "op %d, data in 0x%02x\n", op, data);
+	dev_dbg(pd->dev, "op %d\n", op);
 
 	spin_lock_irqsave(&pd->lock, flags);
 
···
 	case OP_START: /* issue start and trigger DTE interrupt */
 		iic_wr(pd, ICCR, ICCR_ICE | ICCR_TRS | ICCR_BBSY);
 		break;
-	case OP_TX_FIRST: /* disable DTE interrupt and write data */
+	case OP_TX_FIRST: /* disable DTE interrupt and write client address */
 		iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
-		iic_wr(pd, ICDR, data);
+		iic_wr(pd, ICDR, i2c_8bit_addr_from_msg(pd->msg));
 		break;
 	case OP_TX: /* write data */
-		iic_wr(pd, ICDR, data);
+		iic_wr(pd, ICDR, pd->msg->buf[pd->pos]);
 		break;
 	case OP_TX_STOP: /* issue a stop (or rep_start) */
 		iic_wr(pd, ICCR, pd->send_stop ? ICCR_ICE | ICCR_TRS
···
 	return ret;
 }
 
-static bool sh_mobile_i2c_is_first_byte(struct sh_mobile_i2c_data *pd)
-{
-	return pd->pos == -1;
-}
-
-static void sh_mobile_i2c_get_data(struct sh_mobile_i2c_data *pd,
-				   unsigned char *buf)
-{
-	switch (pd->pos) {
-	case -1:
-		*buf = i2c_8bit_addr_from_msg(pd->msg);
-		break;
-	default:
-		*buf = pd->msg->buf[pd->pos];
-	}
-}
-
 static int sh_mobile_i2c_isr_tx(struct sh_mobile_i2c_data *pd)
 {
-	unsigned char data;
-
 	if (pd->pos == pd->msg->len) {
-		i2c_op(pd, OP_TX_STOP, 0);
+		i2c_op(pd, OP_TX_STOP);
 		return 1;
 	}
 
-	sh_mobile_i2c_get_data(pd, &data);
-	i2c_op(pd, sh_mobile_i2c_is_first_byte(pd) ? OP_TX_FIRST : OP_TX, data);
+	if (pd->pos == -1)
+		i2c_op(pd, OP_TX_FIRST);
+	else
+		i2c_op(pd, OP_TX);
 
 	pd->pos++;
 	return 0;
···
 	unsigned char data;
 	int real_pos;
 
-	do {
-		if (pd->pos <= -1) {
-			sh_mobile_i2c_get_data(pd, &data);
+	/* switch from TX (address) to RX (data) adds two interrupts */
+	real_pos = pd->pos - 2;
 
-			if (sh_mobile_i2c_is_first_byte(pd))
-				i2c_op(pd, OP_TX_FIRST, data);
-			else
-				i2c_op(pd, OP_TX, data);
-			break;
+	if (pd->pos == -1) {
+		i2c_op(pd, OP_TX_FIRST);
+	} else if (pd->pos == 0) {
+		i2c_op(pd, OP_TX_TO_RX);
+	} else if (pd->pos == pd->msg->len) {
+		if (pd->stop_after_dma) {
+			/* Simulate PIO end condition after DMA transfer */
+			i2c_op(pd, OP_RX_STOP);
+			pd->pos++;
+			goto done;
 		}
 
-		if (pd->pos == 0) {
-			i2c_op(pd, OP_TX_TO_RX, 0);
-			break;
-		}
+		if (real_pos < 0)
+			i2c_op(pd, OP_RX_STOP);
+		else
+			data = i2c_op(pd, OP_RX_STOP_DATA);
+	} else if (real_pos >= 0) {
+		data = i2c_op(pd, OP_RX);
+	}
 
-		real_pos = pd->pos - 2;
-
-		if (pd->pos == pd->msg->len) {
-			if (pd->stop_after_dma) {
-				/* Simulate PIO end condition after DMA transfer */
-				i2c_op(pd, OP_RX_STOP, 0);
-				pd->pos++;
-				break;
-			}
-
-			if (real_pos < 0) {
-				i2c_op(pd, OP_RX_STOP, 0);
-				break;
-			}
-			data = i2c_op(pd, OP_RX_STOP_DATA, 0);
-		} else if (real_pos >= 0) {
-			data = i2c_op(pd, OP_RX, 0);
-		}
-
-		if (real_pos >= 0)
-			pd->msg->buf[real_pos] = data;
-	} while (0);
-
+	if (real_pos >= 0)
+		pd->msg->buf[real_pos] = data;
+ done:
 	pd->pos++;
 	return pd->pos == (pd->msg->len + 2);
 }
···
 		start_ch(pd, msg, do_start);
 
 		if (do_start)
-			i2c_op(pd, OP_START, 0);
+			i2c_op(pd, OP_START);
 
 		/* The interrupt handler takes care of the rest... */
 		timeout = wait_event_timeout(pd->wait,
···
 };
 
 /*
- * r8a7740 chip has lasting errata on I2C I/O pad reset.
- * this is work-around for it.
+ * r8a7740 has an errata regarding I2C I/O pad reset needing this workaround.
  */
 static int sh_mobile_i2c_r8a7740_workaround(struct sh_mobile_i2c_data *pd)
 {
···
 	{ .compatible = "renesas,iic-r8a7740", .data = &r8a7740_dt_config },
 	{ .compatible = "renesas,iic-r8a774c0", .data = &fast_clock_dt_config },
 	{ .compatible = "renesas,iic-r8a7790", .data = &v2_freq_calc_dt_config },
-	{ .compatible = "renesas,iic-r8a7791", .data = &fast_clock_dt_config },
-	{ .compatible = "renesas,iic-r8a7792", .data = &fast_clock_dt_config },
-	{ .compatible = "renesas,iic-r8a7793", .data = &fast_clock_dt_config },
-	{ .compatible = "renesas,iic-r8a7794", .data = &fast_clock_dt_config },
-	{ .compatible = "renesas,rcar-gen2-iic", .data = &fast_clock_dt_config },
-	{ .compatible = "renesas,iic-r8a7795", .data = &fast_clock_dt_config },
-	{ .compatible = "renesas,rcar-gen3-iic", .data = &fast_clock_dt_config },
-	{ .compatible = "renesas,iic-r8a77990", .data = &fast_clock_dt_config },
+	{ .compatible = "renesas,iic-r8a7791", .data = &v2_freq_calc_dt_config },
+	{ .compatible = "renesas,iic-r8a7792", .data = &v2_freq_calc_dt_config },
+	{ .compatible = "renesas,iic-r8a7793", .data = &v2_freq_calc_dt_config },
+	{ .compatible = "renesas,iic-r8a7794", .data = &v2_freq_calc_dt_config },
+	{ .compatible = "renesas,iic-r8a7795", .data = &v2_freq_calc_dt_config },
+	{ .compatible = "renesas,iic-r8a77990", .data = &v2_freq_calc_dt_config },
 	{ .compatible = "renesas,iic-sh73a0", .data = &fast_clock_dt_config },
+	{ .compatible = "renesas,rcar-gen2-iic", .data = &v2_freq_calc_dt_config },
+	{ .compatible = "renesas,rcar-gen3-iic", .data = &v2_freq_calc_dt_config },
 	{ .compatible = "renesas,rmobile-iic", .data = &default_dt_config },
 	{},
 };

drivers/i2c/busses/i2c-sprd.c

···
 	u32 count;
 	int irq;
 	int err;
-	bool is_suspended;
 };
 
 static void sprd_i2c_set_count(struct sprd_i2c *i2c_dev, u32 count)
···
 {
 	struct sprd_i2c *i2c_dev = i2c_adap->algo_data;
 	int im, ret;
-
-	if (i2c_dev->is_suspended)
-		return -EBUSY;
 
 	ret = pm_runtime_get_sync(i2c_dev->dev);
 	if (ret < 0)
···
 	return 0;
 }
 
-static int __maybe_unused sprd_i2c_suspend_noirq(struct device *pdev)
+static int __maybe_unused sprd_i2c_suspend_noirq(struct device *dev)
 {
-	struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev);
+	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
 
-	i2c_lock_bus(&i2c_dev->adap, I2C_LOCK_ROOT_ADAPTER);
-	i2c_dev->is_suspended = true;
-	i2c_unlock_bus(&i2c_dev->adap, I2C_LOCK_ROOT_ADAPTER);
-
-	return pm_runtime_force_suspend(pdev);
+	i2c_mark_adapter_suspended(&i2c_dev->adap);
+	return pm_runtime_force_suspend(dev);
 }
 
-static int __maybe_unused sprd_i2c_resume_noirq(struct device *pdev)
+static int __maybe_unused sprd_i2c_resume_noirq(struct device *dev)
 {
-	struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev);
+	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
 
-	i2c_lock_bus(&i2c_dev->adap, I2C_LOCK_ROOT_ADAPTER);
-	i2c_dev->is_suspended = false;
-	i2c_unlock_bus(&i2c_dev->adap, I2C_LOCK_ROOT_ADAPTER);
-
-	return pm_runtime_force_resume(pdev);
+	i2c_mark_adapter_resumed(&i2c_dev->adap);
+	return pm_runtime_force_resume(dev);
 }
 
-static int __maybe_unused sprd_i2c_runtime_suspend(struct device *pdev)
+static int __maybe_unused sprd_i2c_runtime_suspend(struct device *dev)
 {
-	struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev);
+	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
 
 	clk_disable_unprepare(i2c_dev->clk);
 
 	return 0;
 }
 
-static int __maybe_unused sprd_i2c_runtime_resume(struct device *pdev)
+static int __maybe_unused sprd_i2c_runtime_resume(struct device *dev)
 {
-	struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev);
+	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
 	int ret;
 
 	ret = clk_prepare_enable(i2c_dev->clk);

drivers/i2c/busses/i2c-synquacer.c

···
 	u32			timeout_ms;
 	enum i2c_state		state;
 	struct i2c_adapter	adapter;
-
-	bool			is_suspended;
 };
 
 static inline int is_lastmsg(struct synquacer_i2c *i2c)
···
 	unsigned char bsr;
 	unsigned long timeout;
 	int ret;
-
-	if (i2c->is_suspended)
-		return -EBUSY;
 
 	synquacer_i2c_hw_init(i2c);
 	bsr = readb(i2c->base + SYNQUACER_I2C_REG_BSR);

drivers/i2c/busses/i2c-tegra.c

···
  * Author: Colin Cross <[e-mail]>
  */
 
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/platform_device.h>
 #include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
 #include <linux/err.h>
 #include <linux/i2c.h>
-#include <linux/io.h>
+#include <linux/init.h>
 #include <linux/interrupt.h>
-#include <linux/delay.h>
-#include <linux/slab.h>
-#include <linux/of_device.h>
-#include <linux/module.h>
-#include <linux/reset.h>
-#include <linux/pinctrl/consumer.h>
-#include <linux/pm_runtime.h>
+#include <linux/io.h>
 #include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
 
-#include <asm/unaligned.h>
-
-#define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000))
 #define BYTES_PER_FIFO_WORD 4
 
 #define I2C_CNFG				0x000
···
 #define I2C_FIFO_CONTROL			0x05c
 #define I2C_FIFO_CONTROL_TX_FLUSH		BIT(1)
 #define I2C_FIFO_CONTROL_RX_FLUSH		BIT(0)
-#define I2C_FIFO_CONTROL_TX_TRIG_SHIFT		5
-#define I2C_FIFO_CONTROL_RX_TRIG_SHIFT		2
+#define I2C_FIFO_CONTROL_TX_TRIG(x)		(((x) - 1) << 5)
+#define I2C_FIFO_CONTROL_RX_TRIG(x)		(((x) - 1) << 2)
 #define I2C_FIFO_STATUS				0x060
 #define I2C_FIFO_STATUS_TX_MASK			0xF0
 #define I2C_FIFO_STATUS_TX_SHIFT		4
···
 #define I2C_FIFO_STATUS_RX_SHIFT		0
 #define I2C_INT_MASK				0x064
 #define I2C_INT_STATUS				0x068
+#define I2C_INT_BUS_CLR_DONE			BIT(11)
 #define I2C_INT_PACKET_XFER_COMPLETE		BIT(7)
 #define I2C_INT_ALL_PACKETS_XFER_COMPLETE	BIT(6)
 #define I2C_INT_TX_FIFO_OVERFLOW		BIT(5)
···
 #define I2C_HEADER_MASTER_ADDR_SHIFT		12
 #define I2C_HEADER_SLAVE_ADDR_SHIFT		1
 
+#define I2C_BUS_CLEAR_CNFG			0x084
+#define I2C_BC_SCLK_THRESHOLD			9
+#define I2C_BC_SCLK_THRESHOLD_SHIFT		16
+#define I2C_BC_STOP_COND			BIT(2)
+#define I2C_BC_TERMINATE			BIT(1)
+#define I2C_BC_ENABLE				BIT(0)
+#define I2C_BUS_CLEAR_STATUS			0x088
+#define I2C_BC_STATUS				BIT(0)
+
 #define I2C_CONFIG_LOAD				0x08C
 #define I2C_MSTR_CONFIG_LOAD			BIT(0)
 #define I2C_SLV_CONFIG_LOAD			BIT(1)
···
 #define I2C_MST_FIFO_STATUS_RX_SHIFT		0
 #define I2C_MST_FIFO_STATUS_TX_MASK		0xff0000
 #define I2C_MST_FIFO_STATUS_TX_SHIFT		16
+
+#define I2C_INTERFACE_TIMING_0			0x94
+#define I2C_THIGH_SHIFT				8
+#define I2C_INTERFACE_TIMING_1			0x98
+
+#define I2C_STANDARD_MODE			100000
+#define I2C_FAST_MODE				400000
+#define I2C_FAST_PLUS_MODE			1000000
+#define I2C_HS_MODE				3500000
+
+/* Packet header size in bytes */
+#define I2C_PACKET_HEADER_SIZE			12
+
+/*
+ * Upto I2C_PIO_MODE_MAX_LEN bytes, controller will use PIO mode,
+ * above this, controller will use DMA to fill FIFO.
+ * MAX PIO len is 20 bytes excluding packet header.
+ */
+#define I2C_PIO_MODE_MAX_LEN			32
 
 /*
  * msg_end_type: The bus control which need to be send at end of transfer.
···
  * @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
+ * @clk_divisor_std_mode: Clock divisor in standard mode. It is
+ *		applicable if there is no fast clock source i.e. single clock
+ *		source.
+ * @clk_divisor_fast_mode: Clock divisor in fast mode. It is
  *		applicable if there is no fast clock source i.e. single clock
  *		source.
  * @clk_divisor_fast_plus_mode: Clock divisor in fast mode plus. It is
···
  *		be transferred in one go.
  * @quirks: i2c adapter quirks for limiting write/read transfer size and not
  *		allowing 0 length transfers.
+ * @supports_bus_clear: Bus Clear support to recover from bus hang during
+ *		SDA stuck low from device for some unknown reasons.
+ * @has_apb_dma: Support of APBDMA on corresponding Tegra chip.
+ * @tlow_std_mode: Low period of the clock in standard mode.
+ * @thigh_std_mode: High period of the clock in standard mode.
+ * @tlow_fast_fastplus_mode: Low period of the clock in fast/fast-plus modes.
+ * @thigh_fast_fastplus_mode: High period of the clock in fast/fast-plus modes.
+ * @setup_hold_time_std_mode: Setup and hold time for start and stop conditions
+ *		in standard mode.
+ * @setup_hold_time_fast_fast_plus_mode: Setup and hold time for start and stop
+ *		conditions in fast/fast-plus modes.
+ * @setup_hold_time_hs_mode: Setup and hold time for start and stop conditions
+ *		in HS mode.
+ * @has_interface_timing_reg: Has interface timing register to program the tuned
+ *		timing settings.
  */
 struct tegra_i2c_hw_feature {
 	bool has_continue_xfer_support;
···
 	bool has_single_clk_source;
 	bool has_config_load_reg;
 	int clk_divisor_hs_mode;
-	int clk_divisor_std_fast_mode;
+	int clk_divisor_std_mode;
+	int clk_divisor_fast_mode;
 	u16 clk_divisor_fast_plus_mode;
 	bool has_multi_master_mode;
 	bool has_slcg_override_reg;
 	bool has_mst_fifo;
 	const struct i2c_adapter_quirks *quirks;
+	bool supports_bus_clear;
+	bool has_apb_dma;
+	u8 tlow_std_mode;
+	u8 thigh_std_mode;
+	u8 tlow_fast_fastplus_mode;
+	u8 thigh_fast_fastplus_mode;
+	u32 setup_hold_time_std_mode;
+	u32 setup_hold_time_fast_fast_plus_mode;
+	u32 setup_hold_time_hs_mode;
+	bool has_interface_timing_reg;
 };
 
 /**
···
  * @fast_clk: clock reference for fast clock of I2C controller
  * @rst: reset control for the I2C controller
  * @base: ioremapped registers cookie
+ * @base_phys: physical base address of the I2C controller
  * @cont_id: I2C controller ID, used for packet header
  * @irq: IRQ number of transfer complete interrupt
  * @irq_disabled: used to track whether or not the interrupt is enabled
···
  * @clk_divisor_non_hs_mode: clock divider for non-high-speed modes
  * @is_multimaster_mode: track if I2C controller is in multi-master mode
  * @xfer_lock: lock to serialize transfer submission and processing
+ * @tx_dma_chan: DMA transmit channel
+ * @rx_dma_chan: DMA receive channel
+ * @dma_phys: handle to DMA resources
+ * @dma_buf: pointer to allocated DMA buffer
+ * @dma_buf_size: DMA buffer size
+ * @is_curr_dma_xfer: indicates active DMA transfer
+ * @dma_complete: DMA completion notifier
  */
 struct tegra_i2c_dev {
 	struct device *dev;
···
 	struct clk *fast_clk;
 	struct reset_control *rst;
 	void __iomem *base;
+	phys_addr_t base_phys;
 	int cont_id;
 	int irq;
 	bool irq_disabled;
···
 	u16 clk_divisor_non_hs_mode;
 	bool is_multimaster_mode;
 	spinlock_t xfer_lock;
+	struct dma_chan *tx_dma_chan;
+	struct dma_chan *rx_dma_chan;
+	dma_addr_t dma_phys;
+	u32 *dma_buf;
+	unsigned int dma_buf_size;
+	bool is_curr_dma_xfer;
+	struct completion dma_complete;
 };
 
 static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
···
 
 	int_mask = i2c_readl(i2c_dev, I2C_INT_MASK) | mask;
 	i2c_writel(i2c_dev, int_mask, I2C_INT_MASK);
+}
+
+static void tegra_i2c_dma_complete(void *args)
+{
+	struct tegra_i2c_dev *i2c_dev = args;
+
+	complete(&i2c_dev->dma_complete);
+}
+
+static int tegra_i2c_dma_submit(struct tegra_i2c_dev *i2c_dev, size_t len)
+{
+	struct dma_async_tx_descriptor *dma_desc;
+	enum dma_transfer_direction dir;
+	struct dma_chan *chan;
+
+	dev_dbg(i2c_dev->dev, "starting DMA for length: %zu\n", len);
+	reinit_completion(&i2c_dev->dma_complete);
+	dir = i2c_dev->msg_read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
+	chan = i2c_dev->msg_read ? i2c_dev->rx_dma_chan : i2c_dev->tx_dma_chan;
+	dma_desc = dmaengine_prep_slave_single(chan, i2c_dev->dma_phys,
+					       len, dir, DMA_PREP_INTERRUPT |
+					       DMA_CTRL_ACK);
+	if (!dma_desc) {
+		dev_err(i2c_dev->dev, "failed to get DMA descriptor\n");
+		return -EINVAL;
+	}
+
+	dma_desc->callback = tegra_i2c_dma_complete;
+	dma_desc->callback_param = i2c_dev;
+	dmaengine_submit(dma_desc);
+	dma_async_issue_pending(chan);
+	return 0;
+}
+
+static void tegra_i2c_release_dma(struct tegra_i2c_dev *i2c_dev)
+{
+	if (i2c_dev->dma_buf) {
+		dma_free_coherent(i2c_dev->dev, i2c_dev->dma_buf_size,
+				  i2c_dev->dma_buf, i2c_dev->dma_phys);
+		i2c_dev->dma_buf = NULL;
+	}
+
+	if (i2c_dev->tx_dma_chan) {
+		dma_release_channel(i2c_dev->tx_dma_chan);
+		i2c_dev->tx_dma_chan = NULL;
+	}
+
+	if (i2c_dev->rx_dma_chan) {
+		dma_release_channel(i2c_dev->rx_dma_chan);
+		i2c_dev->rx_dma_chan = NULL;
+	}
+}
+
+static int tegra_i2c_init_dma(struct tegra_i2c_dev *i2c_dev)
+{
+	struct dma_chan *chan;
+	u32 *dma_buf;
+	dma_addr_t dma_phys;
+	int err;
+
+	if (!i2c_dev->hw->has_apb_dma)
+		return 0;
+
+	if (!IS_ENABLED(CONFIG_TEGRA20_APB_DMA)) {
+		dev_dbg(i2c_dev->dev, "Support for APB DMA not enabled!\n");
+		return 0;
+	}
+
+	chan = dma_request_slave_channel_reason(i2c_dev->dev, "rx");
+	if (IS_ERR(chan)) {
+		err = PTR_ERR(chan);
+		goto err_out;
+	}
+
+	i2c_dev->rx_dma_chan = chan;
+
+	chan = dma_request_slave_channel_reason(i2c_dev->dev, "tx");
+	if (IS_ERR(chan)) {
+		err = PTR_ERR(chan);
+		goto err_out;
+	}
+
+	i2c_dev->tx_dma_chan = chan;
+
+	dma_buf = dma_alloc_coherent(i2c_dev->dev, i2c_dev->dma_buf_size,
+				     &dma_phys, GFP_KERNEL | __GFP_NOWARN);
+	if (!dma_buf) {
+		dev_err(i2c_dev->dev, "failed to allocate the DMA buffer\n");
+		err = -ENOMEM;
+		goto err_out;
+	}
+
+	i2c_dev->dma_buf = dma_buf;
+	i2c_dev->dma_phys = dma_phys;
+	return 0;
+
+err_out:
+	tegra_i2c_release_dma(i2c_dev);
+	if (err != -EPROBE_DEFER) {
+		dev_err(i2c_dev->dev, "cannot use DMA: %d\n", err);
+		dev_err(i2c_dev->dev, "falling back to PIO\n");
+		return 0;
+	}
+
+	return err;
 }
 
 static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev)
···
 	return 0;
 }
 
-static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
+static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev, bool clk_reinit)
 {
 	u32 val;
 	int err;
-	u32 clk_divisor;
+	u32 clk_divisor, clk_multiplier;
+	u32 tsu_thd = 0;
+	u8 tlow, thigh;
 
 	err = pm_runtime_get_sync(i2c_dev->dev);
 	if (err < 0) {
···
 					I2C_CLK_DIVISOR_STD_FAST_MODE_SHIFT;
 	i2c_writel(i2c_dev, clk_divisor, I2C_CLK_DIVISOR);
 
+	if (i2c_dev->bus_clk_rate > I2C_STANDARD_MODE &&
+	    i2c_dev->bus_clk_rate <= I2C_FAST_PLUS_MODE) {
+		tlow = i2c_dev->hw->tlow_fast_fastplus_mode;
+		thigh = i2c_dev->hw->thigh_fast_fastplus_mode;
+		tsu_thd = i2c_dev->hw->setup_hold_time_fast_fast_plus_mode;
+	} else {
+		tlow = i2c_dev->hw->tlow_std_mode;
+		thigh = i2c_dev->hw->thigh_std_mode;
+		tsu_thd = i2c_dev->hw->setup_hold_time_std_mode;
+	}
+
+	if (i2c_dev->hw->has_interface_timing_reg) {
+		val = (thigh << I2C_THIGH_SHIFT) | tlow;
+		i2c_writel(i2c_dev, val, I2C_INTERFACE_TIMING_0);
+	}
+
+	/*
+	 * configure setup and hold times only when tsu_thd is non-zero.
+	 * otherwise, preserve the chip default values
+	 */
+	if (i2c_dev->hw->has_interface_timing_reg && tsu_thd)
+		i2c_writel(i2c_dev, tsu_thd, I2C_INTERFACE_TIMING_1);
+
+	if (!clk_reinit) {
+		clk_multiplier = (tlow + thigh + 2);
+		clk_multiplier *= (i2c_dev->clk_divisor_non_hs_mode + 1);
+		err = clk_set_rate(i2c_dev->div_clk,
+				   i2c_dev->bus_clk_rate * clk_multiplier);
+		if (err) {
+			dev_err(i2c_dev->dev,
+				"failed changing clock rate: %d\n", err);
+			goto err;
+		}
+	}
+
 	if (!i2c_dev->is_dvc) {
 		u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG);
 
···
 		i2c_writel(i2c_dev, sl_cfg, I2C_SL_CNFG);
 		i2c_writel(i2c_dev, 0xfc, I2C_SL_ADDR1);
 		i2c_writel(i2c_dev, 0x00, I2C_SL_ADDR2);
-	}
-
-	if (i2c_dev->hw->has_mst_fifo) {
-		val = I2C_MST_FIFO_CONTROL_TX_TRIG(8) |
-		      I2C_MST_FIFO_CONTROL_RX_TRIG(1);
-		i2c_writel(i2c_dev, val, I2C_MST_FIFO_CONTROL);
-	} else {
-		val = 7 << I2C_FIFO_CONTROL_TX_TRIG_SHIFT |
-			0 << I2C_FIFO_CONTROL_RX_TRIG_SHIFT;
-		i2c_writel(i2c_dev, val, I2C_FIFO_CONTROL);
 	}
 
 	err = tegra_i2c_flush_fifos(i2c_dev);
···
 		goto err;
 	}
 
-	if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
-		if (i2c_dev->msg_buf_remaining)
-			tegra_i2c_empty_rx_fifo(i2c_dev);
-		else
-			BUG();
-	}
+	/*
+	 * I2C transfer is terminated during the bus clear so skip
+	 * processing the other interrupts.
+	 */
+	if (i2c_dev->hw->supports_bus_clear && (status & I2C_INT_BUS_CLR_DONE))
+		goto err;
 
-	if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
-		if (i2c_dev->msg_buf_remaining)
-			tegra_i2c_fill_tx_fifo(i2c_dev);
-		else
-			tegra_i2c_mask_irq(i2c_dev, I2C_INT_TX_FIFO_DATA_REQ);
+	if (!i2c_dev->is_curr_dma_xfer) {
+		if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
+			if (i2c_dev->msg_buf_remaining)
+				tegra_i2c_empty_rx_fifo(i2c_dev);
+			else
+				BUG();
+		}
+
+		if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
+			if (i2c_dev->msg_buf_remaining)
+				tegra_i2c_fill_tx_fifo(i2c_dev);
+			else
+				tegra_i2c_mask_irq(i2c_dev,
+						   I2C_INT_TX_FIFO_DATA_REQ);
+		}
 	}
 
 	i2c_writel(i2c_dev, status, I2C_INT_STATUS);
 	if (i2c_dev->is_dvc)
 		dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
 
+	/*
+	 * During message read XFER_COMPLETE interrupt is triggered prior to
+	 * DMA completion and during message write XFER_COMPLETE interrupt is
+	 * triggered after DMA completion.
+	 * PACKETS_XFER_COMPLETE indicates completion of all bytes of transfer.
+	 * so forcing msg_buf_remaining to 0 in DMA mode.
+	 */
 	if (status & I2C_INT_PACKET_XFER_COMPLETE) {
+		if (i2c_dev->is_curr_dma_xfer)
+			i2c_dev->msg_buf_remaining = 0;
 		BUG_ON(i2c_dev->msg_buf_remaining);
 		complete(&i2c_dev->msg_complete);
 	}
···
 	tegra_i2c_mask_irq(i2c_dev, I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST |
 		I2C_INT_PACKET_XFER_COMPLETE | I2C_INT_TX_FIFO_DATA_REQ |
 		I2C_INT_RX_FIFO_DATA_REQ);
+	if (i2c_dev->hw->supports_bus_clear)
+		tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE);
 	i2c_writel(i2c_dev, status, I2C_INT_STATUS);
 	if (i2c_dev->is_dvc)
 		dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
+
+	if (i2c_dev->is_curr_dma_xfer) {
+		if (i2c_dev->msg_read)
+			dmaengine_terminate_async(i2c_dev->rx_dma_chan);
+		else
+			dmaengine_terminate_async(i2c_dev->tx_dma_chan);
+
+		complete(&i2c_dev->dma_complete);
+	}
 
 	complete(&i2c_dev->msg_complete);
 done:
 	spin_unlock(&i2c_dev->xfer_lock);
 	return IRQ_HANDLED;
+}
+
+static void tegra_i2c_config_fifo_trig(struct tegra_i2c_dev *i2c_dev,
+				       size_t len)
+{
+	u32 val, reg;
+	u8 dma_burst;
+	struct dma_slave_config slv_config = {0};
+	struct dma_chan *chan;
+	int ret;
+	unsigned long reg_offset;
+
+	if (i2c_dev->hw->has_mst_fifo)
+		reg = I2C_MST_FIFO_CONTROL;
+	else
+		reg = I2C_FIFO_CONTROL;
+
+	if (i2c_dev->is_curr_dma_xfer) {
+		if (len & 0xF)
+			dma_burst = 1;
+		else if (len & 0x10)
+			dma_burst = 4;
+		else
+			dma_burst = 8;
+
+		if (i2c_dev->msg_read) {
+			chan = i2c_dev->rx_dma_chan;
+			reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_RX_FIFO);
+			slv_config.src_addr = i2c_dev->base_phys + reg_offset;
+			slv_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+			slv_config.src_maxburst = dma_burst;
+
+			if (i2c_dev->hw->has_mst_fifo)
+				val = I2C_MST_FIFO_CONTROL_RX_TRIG(dma_burst);
+			else
+				val = I2C_FIFO_CONTROL_RX_TRIG(dma_burst);
+		} else {
+			chan = i2c_dev->tx_dma_chan;
+			reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_TX_FIFO);
+			slv_config.dst_addr = i2c_dev->base_phys + reg_offset;
+			slv_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+			slv_config.dst_maxburst = dma_burst;
+
+			if (i2c_dev->hw->has_mst_fifo)
+				val = I2C_MST_FIFO_CONTROL_TX_TRIG(dma_burst);
+			else
+				val = I2C_FIFO_CONTROL_TX_TRIG(dma_burst);
+		}
+
+		slv_config.device_fc = true;
+		ret = dmaengine_slave_config(chan, &slv_config);
+		if (ret < 0) {
+			dev_err(i2c_dev->dev, "DMA slave config failed: %d\n",
+				ret);
+			dev_err(i2c_dev->dev, "falling back to PIO\n");
+			tegra_i2c_release_dma(i2c_dev);
+			i2c_dev->is_curr_dma_xfer = false;
+		} else {
+			goto out;
+		}
+	}
+
+	if (i2c_dev->hw->has_mst_fifo)
+		val = I2C_MST_FIFO_CONTROL_TX_TRIG(8) |
+		      I2C_MST_FIFO_CONTROL_RX_TRIG(1);
+	else
+		val = I2C_FIFO_CONTROL_TX_TRIG(8) |
+		      I2C_FIFO_CONTROL_RX_TRIG(1);
+out:
+	i2c_writel(i2c_dev, val, reg);
+}
+
+static int tegra_i2c_issue_bus_clear(struct i2c_adapter *adap)
+{
+	struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
+	int err;
+	unsigned long time_left;
+	u32 reg;
+
+	reinit_completion(&i2c_dev->msg_complete);
+	reg = (I2C_BC_SCLK_THRESHOLD << I2C_BC_SCLK_THRESHOLD_SHIFT) |
+	      I2C_BC_STOP_COND | I2C_BC_TERMINATE;
+	i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG);
+	if (i2c_dev->hw->has_config_load_reg) {
+		err = tegra_i2c_wait_for_config_load(i2c_dev);
+		if (err)
+			return err;
+	}
+
+	reg |= I2C_BC_ENABLE;
+	i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG);
+	tegra_i2c_unmask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE);
+
+	time_left = wait_for_completion_timeout(&i2c_dev->msg_complete,
+						msecs_to_jiffies(50));
+	if (time_left == 0) {
+		dev_err(i2c_dev->dev, "timed out for bus clear\n");
+		return -ETIMEDOUT;
+	}
+
+	reg = i2c_readl(i2c_dev, I2C_BUS_CLEAR_STATUS);
+	if (!(reg & I2C_BC_STATUS)) {
+		dev_err(i2c_dev->dev,
+			"un-recovered arbitration lost\n");
+		return -EIO;
+	}
+
+	return -EAGAIN;
 }
 
 static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
···
 	u32 int_mask;
 	unsigned long time_left;
 	unsigned long flags;
+	size_t xfer_size;
+	u32 *buffer = NULL;
+	int err = 0;
+	bool dma;
+	u16 xfer_time = 100;
 
 	tegra_i2c_flush_fifos(i2c_dev);
 
···
 	i2c_dev->msg_read = (msg->flags & I2C_M_RD);
 	reinit_completion(&i2c_dev->msg_complete);
 
+	if (i2c_dev->msg_read)
+		xfer_size = msg->len;
+	else
+		xfer_size = msg->len + I2C_PACKET_HEADER_SIZE;
+
+	xfer_size = ALIGN(xfer_size, BYTES_PER_FIFO_WORD);
+	i2c_dev->is_curr_dma_xfer = (xfer_size > I2C_PIO_MODE_MAX_LEN) &&
+				    i2c_dev->dma_buf;
+	tegra_i2c_config_fifo_trig(i2c_dev, xfer_size);
+	dma = i2c_dev->is_curr_dma_xfer;
+	/*
+	 * Transfer time in mSec = Total bits / transfer rate
+	 * Total bits = 9 bits per byte (including ACK bit) + Start & stop bits
+	 */
+	xfer_time += DIV_ROUND_CLOSEST(((xfer_size * 9) + 2) * MSEC_PER_SEC,
+					i2c_dev->bus_clk_rate);
 	spin_lock_irqsave(&i2c_dev->xfer_lock, flags);
 
 	int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST;
 	tegra_i2c_unmask_irq(i2c_dev, int_mask);
+	if (dma) {
+		if (i2c_dev->msg_read) {
+			dma_sync_single_for_device(i2c_dev->dev,
+						   i2c_dev->dma_phys,
+						   xfer_size,
+						   DMA_FROM_DEVICE);
+			err = tegra_i2c_dma_submit(i2c_dev, xfer_size);
+			if (err < 0) {
+				dev_err(i2c_dev->dev,
+					"starting RX DMA failed, err %d\n",
+					err);
+				goto unlock;
+			}
+
+		} else {
+			dma_sync_single_for_cpu(i2c_dev->dev,
+						i2c_dev->dma_phys,
+						xfer_size,
+						DMA_TO_DEVICE);
+			buffer = i2c_dev->dma_buf;
+		}
+	}
 
 	packet_header = (0 << PACKET_HEADER0_HEADER_SIZE_SHIFT) |
 			PACKET_HEADER0_PROTOCOL_I2C |
 			(i2c_dev->cont_id << PACKET_HEADER0_CONT_ID_SHIFT) |
 			(1 << PACKET_HEADER0_PACKET_ID_SHIFT);
-	i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
+	if (dma && !i2c_dev->msg_read)
+		*buffer++ = packet_header;
+	else
+		i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
 
 	packet_header = msg->len - 1;
-	i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
+	if (dma && !i2c_dev->msg_read)
+		*buffer++ = packet_header;
+	else
+		i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
 
 	packet_header = I2C_HEADER_IE_ENABLE;
 	if (end_state == MSG_END_CONTINUE)
···
 		packet_header |= I2C_HEADER_CONT_ON_NAK;
 	if (msg->flags & I2C_M_RD)
 		packet_header |= I2C_HEADER_READ;
-	i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
+	if (dma && !i2c_dev->msg_read)
+		*buffer++ = packet_header;
+	else
+		i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
 
-	if (!(msg->flags & I2C_M_RD))
-		tegra_i2c_fill_tx_fifo(i2c_dev);
+	if (!i2c_dev->msg_read) {
+		if (dma) {
+			memcpy(buffer, msg->buf, msg->len);
+			dma_sync_single_for_device(i2c_dev->dev,
+						   i2c_dev->dma_phys,
+						   xfer_size,
+						   DMA_TO_DEVICE);
+			err = tegra_i2c_dma_submit(i2c_dev, xfer_size);
+			if (err < 0) {
+				dev_err(i2c_dev->dev,
+					"starting TX DMA failed, err %d\n",
+					err);
+				goto unlock;
+			}
+		} else {
+			tegra_i2c_fill_tx_fifo(i2c_dev);
+		}
+	}
 
 	if (i2c_dev->hw->has_per_pkt_xfer_complete_irq)
 		int_mask |= I2C_INT_PACKET_XFER_COMPLETE;
-	if (msg->flags & I2C_M_RD)
-		int_mask |= I2C_INT_RX_FIFO_DATA_REQ;
-	else if (i2c_dev->msg_buf_remaining)
-		int_mask |= I2C_INT_TX_FIFO_DATA_REQ;
+	if (!dma) {
+		if (msg->flags & I2C_M_RD)
+			int_mask |= I2C_INT_RX_FIFO_DATA_REQ;
+		else if (i2c_dev->msg_buf_remaining)
+			int_mask |= I2C_INT_TX_FIFO_DATA_REQ;
+	}
 
 	tegra_i2c_unmask_irq(i2c_dev, int_mask);
-	spin_unlock_irqrestore(&i2c_dev->xfer_lock, flags);
 	dev_dbg(i2c_dev->dev, "unmasked irq: %02x\n",
 		i2c_readl(i2c_dev, I2C_INT_MASK));
 
+unlock:
+	spin_unlock_irqrestore(&i2c_dev->xfer_lock, flags);
+
+	if (dma) {
+		if (err)
+			return err;
+
+		time_left = wait_for_completion_timeout(
+						&i2c_dev->dma_complete,
+						msecs_to_jiffies(xfer_time));
+		if (time_left == 0) {
+			dev_err(i2c_dev->dev, "DMA transfer timeout\n");
+			dmaengine_terminate_sync(i2c_dev->msg_read ?
+						 i2c_dev->rx_dma_chan :
+						 i2c_dev->tx_dma_chan);
+			tegra_i2c_init(i2c_dev, true);
+			return -ETIMEDOUT;
+		}
+
+		if (i2c_dev->msg_read && i2c_dev->msg_err == I2C_ERR_NONE) {
+			dma_sync_single_for_cpu(i2c_dev->dev,
+						i2c_dev->dma_phys,
+						xfer_size,
+						DMA_FROM_DEVICE);
+			memcpy(i2c_dev->msg_buf, i2c_dev->dma_buf,
+			       msg->len);
+		}
+
+		if (i2c_dev->msg_err != I2C_ERR_NONE)
+			dmaengine_synchronize(i2c_dev->msg_read ?
+					      i2c_dev->rx_dma_chan :
+					      i2c_dev->tx_dma_chan);
+	}
+
 	time_left = wait_for_completion_timeout(&i2c_dev->msg_complete,
-						TEGRA_I2C_TIMEOUT);
+						msecs_to_jiffies(xfer_time));
 	tegra_i2c_mask_irq(i2c_dev, int_mask);
 
 	if (time_left == 0) {
 		dev_err(i2c_dev->dev, "i2c transfer timed out\n");
 
-		tegra_i2c_init(i2c_dev);
+		tegra_i2c_init(i2c_dev, true);
 		return -ETIMEDOUT;
 	}
 
···
 		time_left, completion_done(&i2c_dev->msg_complete),
 		i2c_dev->msg_err);
 
+	i2c_dev->is_curr_dma_xfer = false;
 	if (likely(i2c_dev->msg_err == I2C_ERR_NONE))
 		return 0;
 
-	tegra_i2c_init(i2c_dev);
+	tegra_i2c_init(i2c_dev, true);
+	/* start recovery upon arbitration loss in single master mode */
+	if (i2c_dev->msg_err == I2C_ERR_ARBITRATION_LOST) {
+		if (!i2c_dev->is_multimaster_mode)
+			return i2c_recover_bus(&i2c_dev->adapter);
+		return -EAGAIN;
+	}
+
 	if (i2c_dev->msg_err == I2C_ERR_NO_ACK) {
 		if (msg->flags & I2C_M_IGNORE_NAK)
 			return 0;
···
 /* payload size is only 12 bit */
 static const struct i2c_adapter_quirks tegra_i2c_quirks = {
 	.flags = I2C_AQ_NO_ZERO_LEN,
-	.max_read_len = 4096,
-	.max_write_len = 4096,
+	.max_read_len = SZ_4K,
+	.max_write_len = SZ_4K - I2C_PACKET_HEADER_SIZE,
 };
 
 static const struct i2c_adapter_quirks tegra194_i2c_quirks = {
 	.flags = I2C_AQ_NO_ZERO_LEN,
+	.max_write_len = SZ_64K - I2C_PACKET_HEADER_SIZE,
+};
+
+static struct i2c_bus_recovery_info tegra_i2c_recovery_info = {
+	.recover_bus = tegra_i2c_issue_bus_clear,
 };
 
 static const struct tegra_i2c_hw_feature tegra20_i2c_hw = {
···
 	.has_per_pkt_xfer_complete_irq = false,
 	.has_single_clk_source = false,
 	.clk_divisor_hs_mode = 3,
-	.clk_divisor_std_fast_mode = 0,
+	.clk_divisor_std_mode = 0,
+	.clk_divisor_fast_mode = 0,
 	.clk_divisor_fast_plus_mode = 0,
 	.has_config_load_reg = false,
 	.has_multi_master_mode = false,
 	.has_slcg_override_reg = false,
 	.has_mst_fifo = false,
 	.quirks = &tegra_i2c_quirks,
+	.supports_bus_clear = false,
+	.has_apb_dma = true,
+	.tlow_std_mode = 0x4,
+	.thigh_std_mode = 0x2,
+	.tlow_fast_fastplus_mode = 0x4,
+	.thigh_fast_fastplus_mode = 0x2,
+	.setup_hold_time_std_mode = 0x0,
+	.setup_hold_time_fast_fast_plus_mode = 0x0,
+	.setup_hold_time_hs_mode = 0x0,
+	.has_interface_timing_reg = false,
 };
 
 static const struct tegra_i2c_hw_feature tegra30_i2c_hw = {
···
 	.has_per_pkt_xfer_complete_irq = false,
 	.has_single_clk_source = false,
 	.clk_divisor_hs_mode = 3,
-	.clk_divisor_std_fast_mode = 0,
+	.clk_divisor_std_mode = 0,
+	.clk_divisor_fast_mode = 0,
 	.clk_divisor_fast_plus_mode = 0,
 	.has_config_load_reg = false,
 	.has_multi_master_mode = false,
 	.has_slcg_override_reg = false,
 	.has_mst_fifo = false,
 	.quirks = &tegra_i2c_quirks,
+	.supports_bus_clear = false,
+	.has_apb_dma = true,
+	.tlow_std_mode = 0x4,
+	.thigh_std_mode = 0x2,
+	.tlow_fast_fastplus_mode = 0x4,
+	.thigh_fast_fastplus_mode = 0x2,
+	.setup_hold_time_std_mode = 0x0,
+	.setup_hold_time_fast_fast_plus_mode = 0x0,
+	.setup_hold_time_hs_mode = 0x0,
+	.has_interface_timing_reg = false,
 };
 
 static const struct tegra_i2c_hw_feature tegra114_i2c_hw = {
···
 	.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_std_mode = 0x19,
+	.clk_divisor_fast_mode = 0x19,
 	.clk_divisor_fast_plus_mode = 0x10,
 	.has_config_load_reg = false,
 	.has_multi_master_mode = false,
 	.has_slcg_override_reg = false,
 	.has_mst_fifo = false,
 	.quirks = &tegra_i2c_quirks,
+	.supports_bus_clear = true,
+	.has_apb_dma = true,
+	.tlow_std_mode = 0x4,
+	.thigh_std_mode = 0x2,
+	.tlow_fast_fastplus_mode = 0x4,
+	.thigh_fast_fastplus_mode = 0x2,
+	.setup_hold_time_std_mode = 0x0,
+	.setup_hold_time_fast_fast_plus_mode = 0x0,
+	.setup_hold_time_hs_mode = 0x0,
+	.has_interface_timing_reg = false,
 };
 
 static const struct tegra_i2c_hw_feature tegra124_i2c_hw = {
···
 	.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_std_mode = 0x19,
+	.clk_divisor_fast_mode = 0x19,
 	.clk_divisor_fast_plus_mode = 0x10,
 	.has_config_load_reg = true,
 	.has_multi_master_mode = false,
 	.has_slcg_override_reg = true,
 	.has_mst_fifo = false,
 	.quirks = &tegra_i2c_quirks,
+	.supports_bus_clear = true,
+	.has_apb_dma = true,
+	.tlow_std_mode = 0x4,
+	.thigh_std_mode = 0x2,
+	.tlow_fast_fastplus_mode = 0x4,
+	.thigh_fast_fastplus_mode = 0x2,
+	.setup_hold_time_std_mode = 0x0,
+	.setup_hold_time_fast_fast_plus_mode = 0x0,
+	.setup_hold_time_hs_mode = 0x0,
+	.has_interface_timing_reg = true,
 };
 
 static const struct tegra_i2c_hw_feature tegra210_i2c_hw = {
···
 	.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_std_mode = 0x19,
+	.clk_divisor_fast_mode = 0x19,
 	.clk_divisor_fast_plus_mode = 0x10,
 	.has_config_load_reg = true,
-	.has_multi_master_mode = true,
+	.has_multi_master_mode = false,
 	.has_slcg_override_reg = true,
 	.has_mst_fifo = false,
 	.quirks = &tegra_i2c_quirks,
+	.supports_bus_clear = true,
+	.has_apb_dma = true,
+	.tlow_std_mode = 0x4,
+	.thigh_std_mode = 0x2,
+	.tlow_fast_fastplus_mode = 0x4,
+	.thigh_fast_fastplus_mode = 0x2,
+	.setup_hold_time_std_mode = 0,
+	.setup_hold_time_fast_fast_plus_mode = 0,
+	.setup_hold_time_hs_mode = 0,
+	.has_interface_timing_reg = true,
+};
+
+static const struct tegra_i2c_hw_feature tegra186_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_mode = 0x16,
+	.clk_divisor_fast_mode = 0x19,
+	.clk_divisor_fast_plus_mode = 0x10,
+	.has_config_load_reg = true,
+	.has_multi_master_mode = false,
+	.has_slcg_override_reg = true,
+	.has_mst_fifo = false,
+	.quirks = &tegra_i2c_quirks,
+	.supports_bus_clear = true,
+	.has_apb_dma = false,
+	.tlow_std_mode = 0x4,
+	.thigh_std_mode = 0x3,
+	.tlow_fast_fastplus_mode = 0x4,
+	.thigh_fast_fastplus_mode = 0x2,
+	.setup_hold_time_std_mode = 0,
+	.setup_hold_time_fast_fast_plus_mode = 0,
+	.setup_hold_time_hs_mode = 0,
+	.has_interface_timing_reg = true,
 };
 
 static const struct tegra_i2c_hw_feature tegra194_i2c_hw = {
···
 	.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,
+	.clk_divisor_std_mode = 0x4f,
+	.clk_divisor_fast_mode = 0x3c,
+	.clk_divisor_fast_plus_mode = 0x16,
 	.has_config_load_reg = true,
 	.has_multi_master_mode = true,
 	.has_slcg_override_reg = true,
 	.has_mst_fifo = true,
 	.quirks = &tegra194_i2c_quirks,
+	.supports_bus_clear = true,
+	.has_apb_dma = false,
+	.tlow_std_mode = 0x8,
+	.thigh_std_mode = 0x7,
+	.tlow_fast_fastplus_mode = 0x2,
+	.thigh_fast_fastplus_mode = 0x2,
+	.setup_hold_time_std_mode = 0x08080808,
+	.setup_hold_time_fast_fast_plus_mode = 0x02020202,
+	.setup_hold_time_hs_mode = 0x090909,
+	.has_interface_timing_reg = true,
 };
 
 /* Match table for of_platform binding */
 static const struct of_device_id tegra_i2c_of_match[] = {
 	{ .compatible = "nvidia,tegra194-i2c", .data = &tegra194_i2c_hw, },
+	{ .compatible = "nvidia,tegra186-i2c", .data = &tegra186_i2c_hw, },
 	{ .compatible = "nvidia,tegra210-i2c", .data = &tegra210_i2c_hw, },
 	{ .compatible = "nvidia,tegra124-i2c", .data = &tegra124_i2c_hw, },
 	{ .compatible = "nvidia,tegra114-i2c", .data = &tegra114_i2c_hw, },
···
 	struct clk *div_clk;
 	struct clk *fast_clk;
 	void __iomem *base;
+	phys_addr_t base_phys;
 	int irq;
 	int ret = 0;
-	int clk_multiplier = I2C_CLK_MULTIPLIER_STD_FAST_MODE;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base_phys = res->start;
 	base = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(base))
 		return PTR_ERR(base);
···
 		return -ENOMEM;
 
 	i2c_dev->base = base;
+	i2c_dev->base_phys = base_phys;
 	i2c_dev->div_clk = div_clk;
 	i2c_dev->adapter.algo = &tegra_i2c_algo;
+	i2c_dev->adapter.retries = 1;
+	i2c_dev->adapter.timeout = 6 * HZ;
 	i2c_dev->irq = irq;
 	i2c_dev->cont_id = pdev->id;
 	i2c_dev->dev = &pdev->dev;
···
 	i2c_dev->is_dvc = of_device_is_compatible(pdev->dev.of_node,
 						  "nvidia,tegra20-i2c-dvc");
 	i2c_dev->adapter.quirks = i2c_dev->hw->quirks;
+	i2c_dev->dma_buf_size = i2c_dev->adapter.quirks->max_write_len +
+				I2C_PACKET_HEADER_SIZE;
 	init_completion(&i2c_dev->msg_complete);
+	init_completion(&i2c_dev->dma_complete);
 	spin_lock_init(&i2c_dev->xfer_lock);
 
 	if (!i2c_dev->hw->has_single_clk_source) {
···
 		}
 	}
 
-	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))
+	if (i2c_dev->bus_clk_rate > I2C_FAST_MODE &&
+	    i2c_dev->bus_clk_rate <= I2C_FAST_PLUS_MODE)
 		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) {
-		dev_err(i2c_dev->dev, "Clock rate change failed %d\n", ret);
-		goto unprepare_fast_clk;
-	}
+				i2c_dev->hw->clk_divisor_fast_plus_mode;
+	else if (i2c_dev->bus_clk_rate > I2C_STANDARD_MODE &&
+		 i2c_dev->bus_clk_rate <= I2C_FAST_MODE)
+		i2c_dev->clk_divisor_non_hs_mode =
+				i2c_dev->hw->clk_divisor_fast_mode;
+	else
+		i2c_dev->clk_divisor_non_hs_mode =
+				i2c_dev->hw->clk_divisor_std_mode;
 
 	ret = clk_prepare(i2c_dev->div_clk);
 	if (ret < 0) {
···
 		}
 	}
 
-	ret = tegra_i2c_init(i2c_dev);
+	if (i2c_dev->hw->supports_bus_clear)
+		i2c_dev->adapter.bus_recovery_info = &tegra_i2c_recovery_info;
+
+	ret = tegra_i2c_init_dma(i2c_dev);
+	if (ret < 0)
+		goto disable_div_clk;
+
+	ret = tegra_i2c_init(i2c_dev, false);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to initialize i2c controller\n");
-		goto disable_div_clk;
+		goto release_dma;
 	}
 
 	ret = devm_request_irq(&pdev->dev, i2c_dev->irq,
 			tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq);
-		goto disable_div_clk;
+		goto release_dma;
 	}
 
 	i2c_set_adapdata(&i2c_dev->adapter, i2c_dev);
···
 
 	ret = i2c_add_numbered_adapter(&i2c_dev->adapter);
 	if (ret)
-		goto disable_div_clk;
+		goto release_dma;
 
 	return 0;
+
+release_dma:
+	tegra_i2c_release_dma(i2c_dev);
 
 disable_div_clk:
 	if (i2c_dev->is_multimaster_mode)
···
 	if (!i2c_dev->hw->has_single_clk_source)
 		clk_unprepare(i2c_dev->fast_clk);
 
+	tegra_i2c_release_dma(i2c_dev);
 	return 0;
 }
 
···
 	},
 };
 
-static int __init tegra_i2c_init_driver(void)
-{
-	return platform_driver_register(&tegra_i2c_driver);
-}
-
-static void __exit tegra_i2c_exit_driver(void)
-{
-	platform_driver_unregister(&tegra_i2c_driver);
-}
-
-subsys_initcall(tegra_i2c_init_driver);
-module_exit(tegra_i2c_exit_driver);
+module_platform_driver(tegra_i2c_driver);
 
 MODULE_DESCRIPTION("nVidia Tegra2 I2C Bus Controller driver");
 MODULE_AUTHOR("Colin Cross");

drivers/i2c/busses/i2c-zx2967.c

···
 	int			msg_rd;
 	u8			*cur_trans;
 	u8			access_cnt;
-	bool			is_suspended;
 	int			error;
 };
 
···
 	int ret;
 	int i;
 
-	if (i2c->is_suspended)
-		return -EBUSY;
-
 	zx2967_set_addr(i2c, msgs->addr);
 
 	for (i = 0; i < num; i++) {
···
 {
 	struct zx2967_i2c *i2c = dev_get_drvdata(dev);
 
-	i2c->is_suspended = true;
+	i2c_mark_adapter_suspended(&i2c->adap);
 	clk_disable_unprepare(i2c->clk);
 
 	return 0;
···
 {
 	struct zx2967_i2c *i2c = dev_get_drvdata(dev);
 
-	i2c->is_suspended = false;
 	clk_prepare_enable(i2c->clk);
+	i2c_mark_adapter_resumed(&i2c->adap);
 
 	return 0;
 }

drivers/i2c/i2c-core-base.c

···
 	dev_pm_clear_wake_irq(&client->dev);
 	device_init_wakeup(&client->dev, false);
 
-	client->irq = 0;
+	client->irq = client->init_irq;
 
 	return status;
 }
···
 	client->flags = info->flags;
 	client->addr = info->addr;
 
-	client->irq = info->irq;
-	if (!client->irq)
-		client->irq = i2c_dev_irq_from_resources(info->resources,
+	client->init_irq = info->irq;
+	if (!client->init_irq)
+		client->init_irq = i2c_dev_irq_from_resources(info->resources,
 							 info->num_resources);
+	client->irq = client->init_irq;
 
 	strlcpy(client->name, info->type, sizeof(client->name));
 
···
 	if (!adap->lock_ops)
 		adap->lock_ops = &i2c_adapter_lock_ops;
 
+	adap->locked_flags = 0;
 	rt_mutex_init(&adap->bus_lock);
 	rt_mutex_init(&adap->mux_lock);
 	mutex_init(&adap->userspace_clients_lock);
···
 
 	if (WARN_ON(!msgs || num < 1))
 		return -EINVAL;
+	if (WARN_ON(test_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags)))
+		return -ESHUTDOWN;
 
 	if (adap->quirks && i2c_check_for_quirks(adap, msgs, num))
 		return -EOPNOTSUPP;

drivers/i2c/i2c-core-of.c

···
 	return dev->of_node == data;
 }
 
+static int of_dev_or_parent_node_match(struct device *dev, void *data)
+{
+	if (dev->of_node == data)
+		return 1;
+
+	if (dev->parent)
+		return dev->parent->of_node == data;
+
+	return 0;
+}
+
 /* must call put_device() when done with returned i2c_client device */
 struct i2c_client *of_find_i2c_device_by_node(struct device_node *node)
 {
···
 	struct device *dev;
 	struct i2c_adapter *adapter;
 
-	dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
+	dev = bus_find_device(&i2c_bus_type, NULL, node,
+			      of_dev_or_parent_node_match);
 	if (!dev)
 		return NULL;
 

drivers/i2c/i2c-core-smbus.c

···
 trace:
 	/* If enabled, the reply tracepoint is conditional on read_write. */
 	trace_smbus_reply(adapter, addr, flags, read_write,
-			  command, protocol, data);
+			  command, protocol, data, res);
 	trace_smbus_result(adapter, addr, flags, read_write,
 			   command, protocol, res);
 

drivers/i2c/i2c-dev.c

···
 	struct cdev cdev;
 };
 
-#define I2C_MINORS	MINORMASK
+#define I2C_MINORS	(MINORMASK + 1)
 static LIST_HEAD(i2c_dev_list);
 static DEFINE_SPINLOCK(i2c_dev_list_lock);
 

drivers/misc/eeprom/at24.c

···
 #include <linux/i2c.h>
 #include <linux/nvmem-provider.h>
 #include <linux/regmap.h>
-#include <linux/platform_data/at24.h>
 #include <linux/pm_runtime.h>
 #include <linux/gpio/consumer.h>
+
+/* Address pointer is 16 bit. */
+#define AT24_FLAG_ADDR16	BIT(7)
+/* sysfs-entry will be read-only. */
+#define AT24_FLAG_READONLY	BIT(6)
+/* sysfs-entry will be world-readable. */
+#define AT24_FLAG_IRUGO		BIT(5)
+/* Take always 8 addresses (24c00). */
+#define AT24_FLAG_TAKE8ADDR	BIT(4)
+/* Factory-programmed serial number. */
+#define AT24_FLAG_SERIAL	BIT(3)
+/* Factory-programmed mac address. */
+#define AT24_FLAG_MAC		BIT(2)
+/* Does not auto-rollover reads to the next slave address. */
+#define AT24_FLAG_NO_RDROL	BIT(1)
 
 /*
  * I2C EEPROMs from most vendors are inexpensive and mostly interchangeable.
···
 MODULE_PARM_DESC(at24_write_timeout, "Time (in ms) to try writes (default 25)");
 
 struct at24_chip_data {
-	/*
-	 * these fields mirror their equivalents in
-	 * struct at24_platform_data
-	 */
 	u32 byte_len;
 	u8 flags;
 };
···
 	return 0;
 }
 
-static void at24_properties_to_pdata(struct device *dev,
-				     struct at24_platform_data *chip)
-{
-	int err;
-	u32 val;
-
-	if (device_property_present(dev, "read-only"))
-		chip->flags |= AT24_FLAG_READONLY;
-	if (device_property_present(dev, "no-read-rollover"))
-		chip->flags |= AT24_FLAG_NO_RDROL;
-
-	err = device_property_read_u32(dev, "address-width", &val);
-	if (!err) {
-		switch (val) {
-		case 8:
-			if (chip->flags & AT24_FLAG_ADDR16)
-				dev_warn(dev, "Override address width to be 8, while default is 16\n");
-			chip->flags &= ~AT24_FLAG_ADDR16;
-			break;
-		case 16:
-			chip->flags |= AT24_FLAG_ADDR16;
-			break;
-		default:
-			dev_warn(dev, "Bad \"address-width\" property: %u\n",
-				 val);
-		}
-	}
-
-	err = device_property_read_u32(dev, "size", &val);
-	if (!err)
-		chip->byte_len = val;
-
-	err = device_property_read_u32(dev, "pagesize", &val);
-	if (!err) {
-		chip->page_size = val;
-	} else {
-		/*
-		 * This is slow, but we can't know all eeproms, so we better
-		 * play safe. Specifying custom eeprom-types via platform_data
-		 * is recommended anyhow.
-		 */
-		chip->page_size = 1;
-	}
-}
-
-static int at24_get_pdata(struct device *dev, struct at24_platform_data *pdata)
+static const struct at24_chip_data *at24_get_chip_data(struct device *dev)
 {
 	struct device_node *of_node = dev->of_node;
 	const struct at24_chip_data *cdata;
 	const struct i2c_device_id *id;
-	struct at24_platform_data *pd;
-
-	pd = dev_get_platdata(dev);
-	if (pd) {
-		memcpy(pdata, pd, sizeof(*pdata));
-		return 0;
-	}
 
 	id = i2c_match_id(at24_ids, to_i2c_client(dev));
 
···
 		cdata = acpi_device_get_match_data(dev);
 
 	if (!cdata)
-		return -ENODEV;
+		return ERR_PTR(-ENODEV);
 
-	pdata->byte_len = cdata->byte_len;
-	pdata->flags = cdata->flags;
-	at24_properties_to_pdata(dev, pdata);
-
-	return 0;
+	return cdata;
 }
 
 static void at24_remove_dummy_clients(struct at24_data *at24)
···
 {
 	struct regmap_config regmap_config = { };
 	struct nvmem_config nvmem_config = { };
-	struct at24_platform_data pdata = { };
+	u32 byte_len, page_size, flags, addrw;
+	const struct at24_chip_data *cdata;
 	struct device *dev = &client->dev;
 	bool i2c_fn_i2c, i2c_fn_block;
 	unsigned int i, num_addresses;
···
 	i2c_fn_block = i2c_check_functionality(client->adapter,
 					       I2C_FUNC_SMBUS_WRITE_I2C_BLOCK);
 
-	err = at24_get_pdata(dev, &pdata);
+	cdata = at24_get_chip_data(dev);
+	if (IS_ERR(cdata))
+		return PTR_ERR(cdata);
+
+	err = device_property_read_u32(dev, "pagesize", &page_size);
 	if (err)
-		return err;
+		/*
+		 * This is slow, but we can't know all eeproms, so we better
+		 * play safe. Specifying custom eeprom-types via platform_data
+		 * is recommended anyhow.
+		 */
+		page_size = 1;
+
+	flags = cdata->flags;
+	if (device_property_present(dev, "read-only"))
+		flags |= AT24_FLAG_READONLY;
+	if (device_property_present(dev, "no-read-rollover"))
+		flags |= AT24_FLAG_NO_RDROL;
+
+	err = device_property_read_u32(dev, "address-width", &addrw);
+	if (!err) {
+		switch (addrw) {
+		case 8:
+			if (flags & AT24_FLAG_ADDR16)
+				dev_warn(dev,
+					 "Override address width to be 8, while default is 16\n");
+			flags &= ~AT24_FLAG_ADDR16;
+			break;
+		case 16:
+			flags |= AT24_FLAG_ADDR16;
+			break;
+		default:
+			dev_warn(dev, "Bad \"address-width\" property: %u\n",
+				 addrw);
+		}
+	}
+
+	err = device_property_read_u32(dev, "size", &byte_len);
+	if (err)
+		byte_len = cdata->byte_len;
 
 	if (!i2c_fn_i2c && !i2c_fn_block)
-		pdata.page_size = 1;
+		page_size = 1;
 
-	if (!pdata.page_size) {
+	if (!page_size) {
 		dev_err(dev, "page_size must not be 0!\n");
 		return -EINVAL;
 	}
 
-	if (!is_power_of_2(pdata.page_size))
+	if (!is_power_of_2(page_size))
 		dev_warn(dev, "page_size looks suspicious (no power of 2)!\n");
 
-	if (pdata.flags & AT24_FLAG_TAKE8ADDR)
-		num_addresses = 8;
-	else
-		num_addresses =	DIV_ROUND_UP(pdata.byte_len,
-			(pdata.flags & AT24_FLAG_ADDR16) ? 65536 : 256);
+	err = device_property_read_u32(dev, "num-addresses", &num_addresses);
+	if (err) {
+		if (flags & AT24_FLAG_TAKE8ADDR)
+			num_addresses = 8;
+		else
+			num_addresses =	DIV_ROUND_UP(byte_len,
+				(flags & AT24_FLAG_ADDR16) ? 65536 : 256);
+	}
 
-	if ((pdata.flags & AT24_FLAG_SERIAL) && (pdata.flags & AT24_FLAG_MAC)) {
+	if ((flags & AT24_FLAG_SERIAL) && (flags & AT24_FLAG_MAC)) {
 		dev_err(dev,
 			"invalid device data - cannot have both AT24_FLAG_SERIAL & AT24_FLAG_MAC.");
 		return -EINVAL;
 	}
 
 	regmap_config.val_bits = 8;
-	regmap_config.reg_bits = (pdata.flags & AT24_FLAG_ADDR16) ? 16 : 8;
+	regmap_config.reg_bits = (flags & AT24_FLAG_ADDR16) ? 16 : 8;
 	regmap_config.disable_locking = true;
 
 	regmap = devm_regmap_init_i2c(client, &regmap_config);
···
 		return -ENOMEM;
 
 	mutex_init(&at24->lock);
-	at24->byte_len = pdata.byte_len;
-	at24->page_size = pdata.page_size;
-	at24->flags = pdata.flags;
+	at24->byte_len = byte_len;
+	at24->page_size = page_size;
+	at24->flags = flags;
 	at24->num_addresses = num_addresses;
-	at24->offset_adj = at24_get_offset_adj(pdata.flags, pdata.byte_len);
+	at24->offset_adj = at24_get_offset_adj(flags, byte_len);
 	at24->client[0].client = client;
 	at24->client[0].regmap = regmap;
 
···
 	if (IS_ERR(at24->wp_gpio))
 		return PTR_ERR(at24->wp_gpio);
 
-	writable = !(pdata.flags & AT24_FLAG_READONLY);
+	writable = !(flags & AT24_FLAG_READONLY);
 	if (writable) {
 		at24->write_max = min_t(unsigned int,
-					pdata.page_size, at24_io_limit);
+					page_size, at24_io_limit);
 		if (!i2c_fn_i2c && at24->write_max > I2C_SMBUS_BLOCK_MAX)
 			at24->write_max = I2C_SMBUS_BLOCK_MAX;
 	}
···
 	nvmem_config.priv = at24;
 	nvmem_config.stride = 1;
 	nvmem_config.word_size = 1;
-	nvmem_config.size = pdata.byte_len;
+	nvmem_config.size = byte_len;
 
 	at24->nvmem = devm_nvmem_register(dev, &nvmem_config);
 	if (IS_ERR(at24->nvmem)) {
···
 	}
 
 	dev_info(dev, "%u byte %s EEPROM, %s, %u bytes/write\n",
-		 pdata.byte_len, client->name,
+		 byte_len, client->name,
 		 writable ? "writable" : "read-only", at24->write_max);
-
-	/* export data to kernel code */
-	if (pdata.setup)
-		pdata.setup(at24->nvmem, pdata.context);
 
 	return 0;
 

include/linux/acpi.h

···
 }
 #endif
 
-#if defined(CONFIG_ACPI) && IS_ENABLED(CONFIG_I2C)
-bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares,
-			       struct acpi_resource_i2c_serialbus **i2c);
-#else
-static inline bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares,
-					     struct acpi_resource_i2c_serialbus **i2c)
-{
-	return false;
-}
-#endif
-
 /* Device properties */
 
 #ifdef CONFIG_ACPI

include/linux/i2c-algo-bit.h

···
-/* ------------------------------------------------------------------------- */
-/* i2c-algo-bit.h i2c driver algorithms for bit-shift adapters               */
-/* ------------------------------------------------------------------------- */
-/*   Copyright (C) 1995-99 Simon G. Vogl
-
-    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.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
-    MA 02110-1301 USA.							     */
-/* ------------------------------------------------------------------------- */
-
-/* With some changes from Kyösti Mälkki <[e-mail]> and even
-   Frodo Looijaard <[e-mail]> */
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * i2c-algo-bit.h: i2c driver algorithms for bit-shift adapters
+ *
+ *   Copyright (C) 1995-99 Simon G. Vogl
+ * With some changes from Kyösti Mälkki <[e-mail]> and even
+ * Frodo Looijaard <[e-mail]>
+ */
 
 #ifndef _LINUX_I2C_ALGO_BIT_H
 #define _LINUX_I2C_ALGO_BIT_H
+
+#include <linux/i2c.h>
 
 /* --- Defines for bit-adapters ---------------------------------------	*/
 /*

include/linux/i2c.h

···
 	char name[I2C_NAME_SIZE];
 	struct i2c_adapter *adapter;	/* the adapter we sit on	*/
 	struct device dev;		/* the device structure		*/
+	int init_irq;			/* irq set at initialization	*/
 	int irq;			/* irq issued by device		*/
 	struct list_head detected;
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
···
 	int timeout;			/* in jiffies */
 	int retries;
 	struct device dev;		/* the adapter device */
+	unsigned long locked_flags;	/* owned by the I2C core */
+#define I2C_ALF_IS_SUSPENDED	0
 
 	int nr;
 	char name[48];
···
 i2c_unlock_bus(struct i2c_adapter *adapter, unsigned int flags)
 {
 	adapter->lock_ops->unlock_bus(adapter, flags);
+}
+
+/**
+ * i2c_mark_adapter_suspended - Report suspended state of the adapter to the core
+ * @adap: Adapter to mark as suspended
+ *
+ * When using this helper to mark an adapter as suspended, the core will reject
+ * further transfers to this adapter. The usage of this helper is optional but
+ * recommended for devices having distinct handlers for system suspend and
+ * runtime suspend. More complex devices are free to implement custom solutions
+ * to reject transfers when suspended.
+ */
+static inline void i2c_mark_adapter_suspended(struct i2c_adapter *adap)
+{
+	i2c_lock_bus(adap, I2C_LOCK_ROOT_ADAPTER);
+	set_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags);
+	i2c_unlock_bus(adap, I2C_LOCK_ROOT_ADAPTER);
+}
+
+/**
+ * i2c_mark_adapter_resumed - Report resumed state of the adapter to the core
+ * @adap: Adapter to mark as resumed
+ *
+ * When using this helper to mark an adapter as resumed, the core will allow
+ * further transfers to this adapter. See also further notes to
+ * @i2c_mark_adapter_suspended().
+ */
+static inline void i2c_mark_adapter_resumed(struct i2c_adapter *adap)
+{
+	i2c_lock_bus(adap, I2C_LOCK_ROOT_ADAPTER);
+	clear_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags);
+	i2c_unlock_bus(adap, I2C_LOCK_ROOT_ADAPTER);
 }
 
 /*flags for the client struct: */
···
 
 #endif /* CONFIG_OF */
 
+struct acpi_resource;
+struct acpi_resource_i2c_serialbus;
+
 #if IS_ENABLED(CONFIG_ACPI)
+bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares,
+			       struct acpi_resource_i2c_serialbus **i2c);
 u32 i2c_acpi_find_bus_speed(struct device *dev);
 struct i2c_client *i2c_acpi_new_device(struct device *dev, int index,
 				       struct i2c_board_info *info);
 #else
+static inline bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares,
+					     struct acpi_resource_i2c_serialbus **i2c)
+{
+	return false;
+}
 static inline u32 i2c_acpi_find_bus_speed(struct device *dev)
 {
 	return 0;

include/linux/platform_data/at24.h

···
-/*
- * at24.h - platform_data for the at24 (generic eeprom) driver
- * (C) Copyright 2008 by Pengutronix
- * (C) Copyright 2012 by Wolfram Sang
- * same license as the driver
- */
-
-#ifndef _LINUX_AT24_H
-#define _LINUX_AT24_H
-
-#include <linux/types.h>
-#include <linux/nvmem-consumer.h>
-#include <linux/bitops.h>
-
-/**
- * struct at24_platform_data - data to set up at24 (generic eeprom) driver
- * @byte_len: size of eeprom in byte
- * @page_size: number of byte which can be written in one go
- * @flags: tunable options, check AT24_FLAG_* defines
- * @setup: an optional callback invoked after eeprom is probed; enables kernel
-	code to access eeprom via nvmem, see example
- * @context: optional parameter passed to setup()
- *
- * If you set up a custom eeprom type, please double-check the parameters.
- * Especially page_size needs extra care, as you risk data loss if your value
- * is bigger than what the chip actually supports!
- *
- * An example in pseudo code for a setup() callback:
- *
- * void get_mac_addr(struct nvmem_device *nvmem, void *context)
- * {
- *	u8 *mac_addr = ethernet_pdata->mac_addr;
- *	off_t offset = context;
- *
- *	// Read MAC addr from EEPROM
- *	if (nvmem_device_read(nvmem, offset, ETH_ALEN, mac_addr) == ETH_ALEN)
- *		pr_info("Read MAC addr from EEPROM: %pM\n", mac_addr);
- * }
- *
- * This function pointer and context can now be set up in at24_platform_data.
- */
-
-struct at24_platform_data {
-	u32		byte_len;		/* size (sum of all addr) */
-	u16		page_size;		/* for writes */
-	u8		flags;
-#define AT24_FLAG_ADDR16	BIT(7)	/* address pointer is 16 bit */
-#define AT24_FLAG_READONLY	BIT(6)	/* sysfs-entry will be read-only */
-#define AT24_FLAG_IRUGO		BIT(5)	/* sysfs-entry will be world-readable */
-#define AT24_FLAG_TAKE8ADDR	BIT(4)	/* take always 8 addresses (24c00) */
-#define AT24_FLAG_SERIAL	BIT(3)	/* factory-programmed serial number */
-#define AT24_FLAG_MAC		BIT(2)	/* factory-programmed mac address */
-#define AT24_FLAG_NO_RDROL	BIT(1)	/* does not auto-rollover reads to */
-					/* the next slave address */
-
-	void		(*setup)(struct nvmem_device *nvmem, void *context);
-	void		*context;
-};
-
-#endif /* _LINUX_AT24_H */

include/linux/platform_data/i2c-cbus-gpio.h

···
-/*
- * i2c-cbus-gpio.h - CBUS I2C platform_data definition
- *
- * Copyright (C) 2004-2009 Nokia Corporation
- *
- * Written by Felipe Balbi and Aaro Koskinen.
- *
- * This file is subject to the terms and conditions of the GNU General
- * Public License. See the file "COPYING" in the main directory of this
- * archive for more details.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#ifndef __INCLUDE_LINUX_I2C_CBUS_GPIO_H
-#define __INCLUDE_LINUX_I2C_CBUS_GPIO_H
-
-struct i2c_cbus_platform_data {
-	int dat_gpio;
-	int clk_gpio;
-	int sel_gpio;
-};
-
-#endif /* __INCLUDE_LINUX_I2C_CBUS_GPIO_H */

include/linux/platform_data/i2c-ocores.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * i2c-ocores.h - definitions for the i2c-ocores interface
  *
  * Peter Korsgaard <[e-mail]>
- *
- * This file is licensed under the terms of the GNU General Public License
- * version 2.  This program is licensed "as is" without any warranty of any
- * kind, whether express or implied.
  */
 
 #ifndef _LINUX_I2C_OCORES_H
···
 	u32 reg_shift; /* register offset shift value */
 	u32 reg_io_width; /* register io read/write width */
 	u32 clock_khz; /* input clock in kHz */
+	u32 bus_khz; /* bus clock in kHz */
 	bool big_endian; /* registers are big endian */
 	u8 num_devices; /* number of devices in the devices list */
 	struct i2c_board_info const *devices; /* devices connected to the bus */

include/trace/events/smbus.h

···
 	TP_PROTO(const struct i2c_adapter *adap,
 		 u16 addr, unsigned short flags,
 		 char read_write, u8 command, int protocol,
-		 const union i2c_smbus_data *data),
-	TP_ARGS(adap, addr, flags, read_write, command, protocol, data),
-	TP_CONDITION(read_write == I2C_SMBUS_READ),
+		 const union i2c_smbus_data *data, int res),
+	TP_ARGS(adap, addr, flags, read_write, command, protocol, data, res),
+	TP_CONDITION(res >= 0 && read_write == I2C_SMBUS_READ),
 	TP_STRUCT__entry(
 		__field(int,	adapter_nr		)
 		__field(__u16,	addr			)