Merge branch 'i2c/for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:

- the first series of making i2c_device_id optional instead of
mandatory (in favor of alternatives like of_device_id).

This involves adding a new probe callback (probe_new) which removes
some peculiarities I2C had for a long time now. The new probe is
matching the other subsystems now and the old one will be removed
once all users are converted. It is expected to take a while but
there is ongoing interest in that.

- SMBus Host Notify introduced 4.9 got refactored. They are now using
interrupts instead of the alert callback which solves multiple
issues.

- new drivers for iMX LowPower I2C, Mellanox CPLD and its I2C mux

- significant refactoring for bcm2835 driver

- the usual set of driver updates and improvements

* 'i2c/for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (46 commits)
i2c: fsl-lpi2c: read lpi2c fifo size in probe()
i2c: octeon: thunderx: Remove double-check after interrupt
i2c: octeon: thunderx: TWSI software reset in recovery
i2c: cadence: Allow Cadence I2C to be selected for Cadence Xtensa CPUs
i2c: sh_mobile: Add per-Generation fallback bindings
i2c: rcar: Add per-Generation fallback bindings
i2c: imx-lpi2c: add low power i2c bus driver
dt-bindings: i2c: imx-lpi2c: add devicetree bindings
i2c: designware-pcidrv: Add 10bit address feature to medfield/merrifield
i2c: pxa: Add support for the I2C units found in Armada 3700
i2c: pxa: Add definition of fast and high speed modes via the regs layout
dt-bindings: i2c: pxa: Update the documentation for the Armada 3700
i2c: qup: support SMBus block read
i2c: qup: add ACPI support
i2c: designware: Consolidate default functionality bits
i2c: i2c-mux-gpio: update mux with gpiod_set_array_value_cansleep
i2c: mux: pca954x: Add ACPI support for pca954x
i2c: use an IRQ to report Host Notify events, not alert
i2c: i801: remove SMBNTFDDAT reads as they always seem to return 0
i2c: i801: use the BIT() macro for FEATURES_* also
...

Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.txt

···
+* Freescale Low Power Inter IC (LPI2C) for i.MX
+
+Required properties:
+- compatible :
+  - "fsl,imx7ulp-lpi2c" for LPI2C compatible with the one integrated on i.MX7ULP soc
+  - "fsl,imx8dv-lpi2c" for LPI2C compatible with the one integrated on i.MX8DV soc
+- reg : address and length of the lpi2c master registers
+- interrupt-parent : core interrupt controller
+- interrupts : lpi2c interrupt
+- clocks : lpi2c clock specifier
+
+Examples:
+
+lpi2c7: lpi2c7@40A50000 {
+	compatible = "fsl,imx8dv-lpi2c";
+	reg = <0x40A50000 0x10000>;
+	interrupt-parent = <&intc>;
+	interrupts = <GIC_SPI 37 IRQ_TYPE_LEVEL_HIGH>;
+	clocks = <&clks IMX7ULP_CLK_LPI2C7>;
+};

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

···
    compatible processor, e.g. pxa168, pxa910, mmp2, mmp3.
    For the pxa2xx/pxa3xx, an additional node "mrvl,pxa-i2c" is required
    as shown in the example below.
+   For the Armada 3700, the compatible should be "marvell,armada-3700-i2c".
 
 Recommended properties :
 

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

···
 I2C for R-Car platforms
 
 Required properties:
-- compatible: Must be one of
-	"renesas,i2c-rcar"
-	"renesas,i2c-r8a7778"
-	"renesas,i2c-r8a7779"
-	"renesas,i2c-r8a7790"
-	"renesas,i2c-r8a7791"
-	"renesas,i2c-r8a7792"
-	"renesas,i2c-r8a7793"
-	"renesas,i2c-r8a7794"
-	"renesas,i2c-r8a7795"
-	"renesas,i2c-r8a7796"
+- compatible:
+	"renesas,i2c-r8a7778" if the device is a part of a R8A7778 SoC.
+	"renesas,i2c-r8a7779" if the device is a part of a R8A7779 SoC.
+	"renesas,i2c-r8a7790" if the device is a part of a R8A7790 SoC.
+	"renesas,i2c-r8a7791" if the device is a part of a R8A7791 SoC.
+	"renesas,i2c-r8a7792" if the device is a part of a R8A7792 SoC.
+	"renesas,i2c-r8a7793" if the device is a part of a R8A7793 SoC.
+	"renesas,i2c-r8a7794" if the device is a part of a R8A7794 SoC.
+	"renesas,i2c-r8a7795" if the device is a part of a R8A7795 SoC.
+	"renesas,i2c-r8a7796" if the device is a part of a R8A7796 SoC.
+	"renesas,rcar-gen1-i2c" for a generic R-Car Gen1 compatible device.
+	"renesas,rcar-gen2-i2c" for a generic R-Car Gen2 compatible device.
+	"renesas,rcar-gen3-i2c" for a generic R-Car Gen3 compatible device.
+	"renesas,i2c-rcar" (deprecated)
+
+	When compatible with the generic version, nodes must list the
+	SoC-specific version corresponding to the platform first followed
+	by the generic version.
+
 - reg: physical base address of the controller and length of memory mapped
   region.
 - interrupts: interrupt specifier.
···
 i2c0: i2c@e6508000 {
 	#address-cells = <1>;
 	#size-cells = <0>;
-	compatible = "renesas,i2c-r8a7791";
+	compatible = "renesas,i2c-r8a7791", "renesas,rcar-gen2-i2c";
 	reg = <0 0xe6508000 0 0x40>;
 	interrupts = <0 287 IRQ_TYPE_LEVEL_HIGH>;
 	clocks = <&mstp9_clks R8A7791_CLK_I2C0>;

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

···
 Device tree configuration for Renesas IIC (sh_mobile) driver
 
 Required properties:
-- compatible      : "renesas,iic-<soctype>". "renesas,rmobile-iic" as fallback
-		     Examples with soctypes are:
+- compatible      :
 			- "renesas,iic-r8a73a4" (R-Mobile APE6)
 			- "renesas,iic-r8a7740" (R-Mobile A1)
 			- "renesas,iic-r8a7790" (R-Car H2)
···
 			- "renesas,iic-r8a7794" (R-Car E2)
 			- "renesas,iic-r8a7795" (R-Car H3)
 			- "renesas,iic-sh73a0" (SH-Mobile AG5)
+			- "renesas,rcar-gen2-iic" (generic R-Car Gen2 compatible device)
+			- "renesas,rcar-gen3-iic" (generic R-Car Gen3 compatible device)
+			- "renesas,rmobile-iic" (generic device)
+
+			When compatible with a generic R-Car version, nodes
+			must list the SoC-specific version corresponding to
+			the platform first followed by the generic R-Car
+			version.
+
+			renesas,rmobile-iic must always follow.
+
 - reg             : address start and address range size of device
 - interrupts      : interrupt of device
 - clocks          : clock for device
···
 Example:
 
 	iic0: i2c@e6500000 {
-		compatible = "renesas,iic-r8a7790", "renesas,rmobile-iic";
+		compatible = "renesas,iic-r8a7790", "renesas,rcar-gen2-iic",
+			     "renesas,rmobile-iic";
 		reg = <0 0xe6500000 0 0x425>;
 		interrupts = <0 174 IRQ_TYPE_LEVEL_HIGH>;
 		clocks = <&mstp3_clks R8A7790_CLK_IIC0>;

Documentation/i2c/busses/i2c-mlxcpld

···
+Driver i2c-mlxcpld
+
+Author: Michael Shych <[e-mail]>
+
+This is the Mellanox I2C controller logic, implemented in Lattice CPLD
+device.
+Device supports:
+ - Master mode.
+ - One physical bus.
+ - Polling mode.
+
+This controller is equipped within the next Mellanox systems:
+"msx6710", "msx6720", "msb7700", "msn2700", "msx1410", "msn2410", "msb7800",
+"msn2740", "msn2100".
+
+The next transaction types are supported:
+ - Receive Byte/Block.
+ - Send Byte/Block.
+ - Read Byte/Block.
+ - Write Byte/Block.
+
+Registers:
+CTRL		0x1 - control reg.
+			Resets all the registers.
+HALF_CYC	0x4 - cycle reg.
+			Configure the width of I2C SCL half clock cycle (in 4 LPC_CLK
+			units).
+I2C_HOLD	0x5 - hold reg.
+			OE (output enable) is delayed by value set to this register
+			(in LPC_CLK units)
+CMD			0x6 - command reg.
+			Bit 0, 0 = write, 1 = read.
+			Bits [7:1] - the 7bit Address of the I2C device.
+			It should be written last as it triggers an I2C transaction.
+NUM_DATA	0x7 - data size reg.
+			Number of data bytes to write in read transaction
+NUM_ADDR	0x8 - address reg.
+			Number of address bytes to write in read transaction.
+STATUS		0x9 - status reg.
+			Bit 0 - transaction is completed.
+			Bit 4 - ACK/NACK.
+DATAx		0xa - 0x54  - 68 bytes data buffer regs.
+			For write transaction address is specified in four first bytes
+			(DATA1 - DATA4), data starting from DATA4.
+			For read transactions address is sent in a separate transaction and
+			specified in the four first bytes (DATA0 - DATA3). Data is read
+			starting from DATA0.

Documentation/i2c/smbus-protocol

···
 [S] [HostAddr] [Wr] A [DevAddr] A [DataLow] A [DataHigh] A [P]
 
 This is implemented in the following way in the Linux kernel:
-* I2C bus drivers which support SMBus Host Notify should call
-  i2c_setup_smbus_host_notify() to setup SMBus Host Notify support.
-* I2C drivers for devices which can trigger SMBus Host Notify should implement
-  the optional alert() callback.
+* I2C bus drivers which support SMBus Host Notify should report
+  I2C_FUNC_SMBUS_HOST_NOTIFY.
+* I2C bus drivers trigger SMBus Host Notify by a call to
+  i2c_handle_smbus_host_notify().
+* I2C drivers for devices which can trigger SMBus Host Notify will have
+  client->irq assigned to a Host Notify IRQ if noone else specified an other.
+
+There is currently no way to retrieve the data parameter from the client.
 
 
 Packet Error Checking (PEC)

MAINTAINERS

···
 Q:	http://patchwork.ozlabs.org/project/netdev/list/
 F:	drivers/net/ethernet/mellanox/mlxsw/
 
+MELLANOX MLXCPLD I2C AND MUX DRIVER
+M:	Vadim Pasternak <[e-mail]>
+M:	Michael Shych <[e-mail]>
+L:	[e-mail]
+S:	Supported
+F:	drivers/i2c/busses/i2c-mlxcpld.c
+F:	drivers/i2c/muxes/i2c-mux-mlxcpld.c
+F:	Documentation/i2c/busses/i2c-mlxcpld
+
 MELLANOX MLXCPLD LED DRIVER
 M:	Vadim Pasternak <[e-mail]>
 L:	[e-mail]

drivers/i2c/Kconfig

···
 config I2C
 	tristate "I2C support"
 	select RT_MUTEXES
+	select IRQ_DOMAIN
 	---help---
 	  I2C (pronounce: I-squared-C) is a slow serial bus protocol used in
 	  many micro controller applications and developed by Philips.  SMBus,

drivers/i2c/busses/Kconfig

···
 
 config I2C_CADENCE
 	tristate "Cadence I2C Controller"
-	depends on ARCH_ZYNQ || ARM64
+	depends on ARCH_ZYNQ || ARM64 || XTENSA
 	help
 	  Say yes here to select Cadence I2C Host Controller. This controller is
 	  e.g. used by Xilinx Zynq.
···
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-imx.
 
+config I2C_IMX_LPI2C
+	tristate "IMX Low Power I2C interface"
+	depends on ARCH_MXC || COMPILE_TEST
+	help
+          Say Y here if you want to use the Low Power IIC bus controller
+          on the Freescale i.MX processors.
+
+          This driver can also be built as a module. If so, the module
+          will be called i2c-imx-lpi2c.
+
 config I2C_IOP3XX
 	tristate "Intel IOPx3xx and IXP4xx on-chip I2C interface"
 	depends on ARCH_IOP32X || ARCH_IOP33X || ARCH_IXP4XX || ARCH_IOP13XX
···
 
 config I2C_PXA
 	tristate "Intel PXA2XX I2C adapter"
-	depends on ARCH_PXA || ARCH_MMP || (X86_32 && PCI && OF)
+	depends on ARCH_PXA || ARCH_MMP || ARCH_MVEBU || (X86_32 && PCI && OF)
 	help
 	  If you have devices in the PXA I2C bus, say yes to this option.
 	  This driver can also be built as a module.  If so, the module
···
 
 	  This support is also available as a module.  If so, the module
 	  will be called i2c-elektor.
+
+config I2C_MLXCPLD
+	tristate "Mellanox I2C driver"
+	depends on X86_64
+	help
+	  This exposes the Mellanox platform I2C busses to the linux I2C layer
+	  for X86 based systems.
+	  Controller is implemented as CPLD logic.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called as i2c-mlxcpld.
 
 config I2C_PCA_ISA
 	tristate "PCA9564/PCA9665 on an ISA bus"

drivers/i2c/busses/Makefile

···
 obj-$(CONFIG_I2C_IBM_IIC)	+= i2c-ibm_iic.o
 obj-$(CONFIG_I2C_IMG)		+= i2c-img-scb.o
 obj-$(CONFIG_I2C_IMX)		+= i2c-imx.o
+obj-$(CONFIG_I2C_IMX_LPI2C)	+= i2c-imx-lpi2c.o
 obj-$(CONFIG_I2C_IOP3XX)	+= i2c-iop3xx.o
 obj-$(CONFIG_I2C_JZ4780)	+= i2c-jz4780.o
 obj-$(CONFIG_I2C_KEMPLD)	+= i2c-kempld.o
···
 obj-$(CONFIG_I2C_BRCMSTB)	+= i2c-brcmstb.o
 obj-$(CONFIG_I2C_CROS_EC_TUNNEL)	+= i2c-cros-ec-tunnel.o
 obj-$(CONFIG_I2C_ELEKTOR)	+= i2c-elektor.o
+obj-$(CONFIG_I2C_MLXCPLD)	+= i2c-mlxcpld.o
 obj-$(CONFIG_I2C_OPAL)		+= i2c-opal.o
 obj-$(CONFIG_I2C_PCA_ISA)	+= i2c-pca-isa.o
 obj-$(CONFIG_I2C_SIBYTE)	+= i2c-sibyte.o

drivers/i2c/busses/i2c-axxia.c

···
 	.functionality = axxia_i2c_func,
 };
 
-static struct i2c_adapter_quirks axxia_i2c_quirks = {
+static const struct i2c_adapter_quirks axxia_i2c_quirks = {
 	.max_read_len = 255,
 	.max_write_len = 255,
 };

drivers/i2c/busses/i2c-bcm-iproc.c

···
 	.functionality = bcm_iproc_i2c_functionality,
 };
 
-static struct i2c_adapter_quirks bcm_iproc_i2c_quirks = {
+static const struct i2c_adapter_quirks bcm_iproc_i2c_quirks = {
 	/* need to reserve one byte in the FIFO for the slave address */
 	.max_read_len = M_TX_RX_FIFO_SIZE - 1,
 };

drivers/i2c/busses/i2c-bcm2835.c

···
 #define BCM2835_I2C_S_CLKT	BIT(9)
 #define BCM2835_I2C_S_LEN	BIT(10) /* Fake bit for SW error reporting */
 
-#define BCM2835_I2C_BITMSK_S	0x03FF
-
 #define BCM2835_I2C_CDIV_MIN	0x0002
 #define BCM2835_I2C_CDIV_MAX	0xFFFE
-
-#define BCM2835_I2C_TIMEOUT (msecs_to_jiffies(1000))
 
 struct bcm2835_i2c_dev {
 	struct device *dev;
 	void __iomem *regs;
 	struct clk *clk;
 	int irq;
+	u32 bus_clk_rate;
 	struct i2c_adapter adapter;
 	struct completion completion;
+	struct i2c_msg *curr_msg;
+	int num_msgs;
 	u32 msg_err;
 	u8 *msg_buf;
 	size_t msg_buf_remaining;
···
 static inline u32 bcm2835_i2c_readl(struct bcm2835_i2c_dev *i2c_dev, u32 reg)
 {
 	return readl(i2c_dev->regs + reg);
+}
+
+static int bcm2835_i2c_set_divider(struct bcm2835_i2c_dev *i2c_dev)
+{
+	u32 divider;
+
+	divider = DIV_ROUND_UP(clk_get_rate(i2c_dev->clk),
+			       i2c_dev->bus_clk_rate);
+	/*
+	 * Per the datasheet, the register is always interpreted as an even
+	 * number, by rounding down. In other words, the LSB is ignored. So,
+	 * if the LSB is set, increment the divider to avoid any issue.
+	 */
+	if (divider & 1)
+		divider++;
+	if ((divider < BCM2835_I2C_CDIV_MIN) ||
+	    (divider > BCM2835_I2C_CDIV_MAX)) {
+		dev_err_ratelimited(i2c_dev->dev, "Invalid clock-frequency\n");
+		return -EINVAL;
+	}
+
+	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_DIV, divider);
+
+	return 0;
 }
 
 static void bcm2835_fill_txfifo(struct bcm2835_i2c_dev *i2c_dev)
···
 	}
 }
 
+/*
+ * Repeated Start Condition (Sr)
+ * The BCM2835 ARM Peripherals datasheet mentions a way to trigger a Sr when it
+ * talks about reading from a slave with 10 bit address. This is achieved by
+ * issuing a write, poll the I2CS.TA flag and wait for it to be set, and then
+ * issue a read.
+ * A comment in https://github.com/raspberrypi/linux/issues/254 shows how the
+ * firmware actually does it using polling and says that it's a workaround for
+ * a problem in the state machine.
+ * It turns out that it is possible to use the TXW interrupt to know when the
+ * transfer is active, provided the FIFO has not been prefilled.
+ */
+
+static void bcm2835_i2c_start_transfer(struct bcm2835_i2c_dev *i2c_dev)
+{
+	u32 c = BCM2835_I2C_C_ST | BCM2835_I2C_C_I2CEN;
+	struct i2c_msg *msg = i2c_dev->curr_msg;
+	bool last_msg = (i2c_dev->num_msgs == 1);
+
+	if (!i2c_dev->num_msgs)
+		return;
+
+	i2c_dev->num_msgs--;
+	i2c_dev->msg_buf = msg->buf;
+	i2c_dev->msg_buf_remaining = msg->len;
+
+	if (msg->flags & I2C_M_RD)
+		c |= BCM2835_I2C_C_READ | BCM2835_I2C_C_INTR;
+	else
+		c |= BCM2835_I2C_C_INTT;
+
+	if (last_msg)
+		c |= BCM2835_I2C_C_INTD;
+
+	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_A, msg->addr);
+	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_DLEN, msg->len);
+	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, c);
+}
+
+/*
+ * Note about I2C_C_CLEAR on error:
+ * The I2C_C_CLEAR on errors will take some time to resolve -- if you were in
+ * non-idle state and I2C_C_READ, it sets an abort_rx flag and runs through
+ * the state machine to send a NACK and a STOP. Since we're setting CLEAR
+ * without I2CEN, that NACK will be hanging around queued up for next time
+ * we start the engine.
+ */
+
 static irqreturn_t bcm2835_i2c_isr(int this_irq, void *data)
 {
 	struct bcm2835_i2c_dev *i2c_dev = data;
 	u32 val, err;
 
 	val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S);
-	val &= BCM2835_I2C_BITMSK_S;
-	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_S, val);
 
 	err = val & (BCM2835_I2C_S_CLKT | BCM2835_I2C_S_ERR);
 	if (err) {
 		i2c_dev->msg_err = err;
-		complete(&i2c_dev->completion);
-		return IRQ_HANDLED;
-	}
-
-	if (val & BCM2835_I2C_S_RXD) {
-		bcm2835_drain_rxfifo(i2c_dev);
-		if (!(val & BCM2835_I2C_S_DONE))
-			return IRQ_HANDLED;
+		goto complete;
 	}
 
 	if (val & BCM2835_I2C_S_DONE) {
-		if (i2c_dev->msg_buf_remaining)
+		if (i2c_dev->curr_msg->flags & I2C_M_RD) {
+			bcm2835_drain_rxfifo(i2c_dev);
+			val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S);
+		}
+
+		if ((val & BCM2835_I2C_S_RXD) || i2c_dev->msg_buf_remaining)
 			i2c_dev->msg_err = BCM2835_I2C_S_LEN;
 		else
 			i2c_dev->msg_err = 0;
-		complete(&i2c_dev->completion);
+		goto complete;
+	}
+
+	if (val & BCM2835_I2C_S_TXW) {
+		if (!i2c_dev->msg_buf_remaining) {
+			i2c_dev->msg_err = val | BCM2835_I2C_S_LEN;
+			goto complete;
+		}
+
+		bcm2835_fill_txfifo(i2c_dev);
+
+		if (i2c_dev->num_msgs && !i2c_dev->msg_buf_remaining) {
+			i2c_dev->curr_msg++;
+			bcm2835_i2c_start_transfer(i2c_dev);
+		}
+
 		return IRQ_HANDLED;
 	}
 
-	if (val & BCM2835_I2C_S_TXD) {
-		bcm2835_fill_txfifo(i2c_dev);
+	if (val & BCM2835_I2C_S_RXR) {
+		if (!i2c_dev->msg_buf_remaining) {
+			i2c_dev->msg_err = val | BCM2835_I2C_S_LEN;
+			goto complete;
+		}
+
+		bcm2835_drain_rxfifo(i2c_dev);
 		return IRQ_HANDLED;
 	}
 
 	return IRQ_NONE;
-}
 
-static int bcm2835_i2c_xfer_msg(struct bcm2835_i2c_dev *i2c_dev,
-				struct i2c_msg *msg)
-{
-	u32 c;
-	unsigned long time_left;
-
-	i2c_dev->msg_buf = msg->buf;
-	i2c_dev->msg_buf_remaining = msg->len;
-	reinit_completion(&i2c_dev->completion);
-
+complete:
 	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, BCM2835_I2C_C_CLEAR);
+	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_S, BCM2835_I2C_S_CLKT |
+			   BCM2835_I2C_S_ERR | BCM2835_I2C_S_DONE);
+	complete(&i2c_dev->completion);
 
-	if (msg->flags & I2C_M_RD) {
-		c = BCM2835_I2C_C_READ | BCM2835_I2C_C_INTR;
-	} else {
-		c = BCM2835_I2C_C_INTT;
-		bcm2835_fill_txfifo(i2c_dev);
-	}
-	c |= BCM2835_I2C_C_ST | BCM2835_I2C_C_INTD | BCM2835_I2C_C_I2CEN;
-
-	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_A, msg->addr);
-	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_DLEN, msg->len);
-	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, c);
-
-	time_left = wait_for_completion_timeout(&i2c_dev->completion,
-						BCM2835_I2C_TIMEOUT);
-	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, BCM2835_I2C_C_CLEAR);
-	if (!time_left) {
-		dev_err(i2c_dev->dev, "i2c transfer timed out\n");
-		return -ETIMEDOUT;
-	}
-
-	if (likely(!i2c_dev->msg_err))
-		return 0;
-
-	if ((i2c_dev->msg_err & BCM2835_I2C_S_ERR) &&
-	    (msg->flags & I2C_M_IGNORE_NAK))
-		return 0;
-
-	dev_err(i2c_dev->dev, "i2c transfer failed: %x\n", i2c_dev->msg_err);
-
-	if (i2c_dev->msg_err & BCM2835_I2C_S_ERR)
-		return -EREMOTEIO;
-	else
-		return -EIO;
+	return IRQ_HANDLED;
 }
 
 static int bcm2835_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
 			    int num)
 {
 	struct bcm2835_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
-	int i;
-	int ret = 0;
+	unsigned long time_left;
+	int i, ret;
 
-	for (i = 0; i < num; i++) {
-		ret = bcm2835_i2c_xfer_msg(i2c_dev, &msgs[i]);
-		if (ret)
-			break;
+	for (i = 0; i < (num - 1); i++)
+		if (msgs[i].flags & I2C_M_RD) {
+			dev_warn_once(i2c_dev->dev,
+				      "only one read message supported, has to be last\n");
+			return -EOPNOTSUPP;
+		}
+
+	ret = bcm2835_i2c_set_divider(i2c_dev);
+	if (ret)
+		return ret;
+
+	i2c_dev->curr_msg = msgs;
+	i2c_dev->num_msgs = num;
+	reinit_completion(&i2c_dev->completion);
+
+	bcm2835_i2c_start_transfer(i2c_dev);
+
+	time_left = wait_for_completion_timeout(&i2c_dev->completion,
+						adap->timeout);
+	if (!time_left) {
+		bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C,
+				   BCM2835_I2C_C_CLEAR);
+		dev_err(i2c_dev->dev, "i2c transfer timed out\n");
+		return -ETIMEDOUT;
 	}
 
-	return ret ?: i;
+	if (!i2c_dev->msg_err)
+		return num;
+
+	dev_dbg(i2c_dev->dev, "i2c transfer failed: %x\n", i2c_dev->msg_err);
+
+	if (i2c_dev->msg_err & BCM2835_I2C_S_ERR)
+		return -EREMOTEIO;
+
+	return -EIO;
 }
 
 static u32 bcm2835_i2c_func(struct i2c_adapter *adap)
···
 {
 	struct bcm2835_i2c_dev *i2c_dev;
 	struct resource *mem, *irq;
-	u32 bus_clk_rate, divider;
 	int ret;
 	struct i2c_adapter *adap;
 
···
 	}
 
 	ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency",
-				   &bus_clk_rate);
+				   &i2c_dev->bus_clk_rate);
 	if (ret < 0) {
 		dev_warn(&pdev->dev,
 			 "Could not read clock-frequency property\n");
-		bus_clk_rate = 100000;
+		i2c_dev->bus_clk_rate = 100000;
 	}
-
-	divider = DIV_ROUND_UP(clk_get_rate(i2c_dev->clk), bus_clk_rate);
-	/*
-	 * Per the datasheet, the register is always interpreted as an even
-	 * number, by rounding down. In other words, the LSB is ignored. So,
-	 * if the LSB is set, increment the divider to avoid any issue.
-	 */
-	if (divider & 1)
-		divider++;
-	if ((divider < BCM2835_I2C_CDIV_MIN) ||
-	    (divider > BCM2835_I2C_CDIV_MAX)) {
-		dev_err(&pdev->dev, "Invalid clock-frequency\n");
-		return -ENODEV;
-	}
-	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_DIV, divider);
 
 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (!irq) {

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

···
 	intr_mask = DW_IC_INTR_DEFAULT_MASK;
 
 	for (; dev->msg_write_idx < dev->msgs_num; dev->msg_write_idx++) {
+		u32 flags = msgs[dev->msg_write_idx].flags;
+
 		/*
 		 * if target address has changed, we need to
 		 * reprogram the target address in the i2c
···
 			 * detected from the registers so we set it always
 			 * when writing/reading the last byte.
 			 */
+
+			/*
+			 * i2c-core.c always sets the buffer length of
+			 * I2C_FUNC_SMBUS_BLOCK_DATA to 1. The length will
+			 * be adjusted when receiving the first byte.
+			 * Thus we can't stop the transaction here.
+			 */
 			if (dev->msg_write_idx == dev->msgs_num - 1 &&
-			    buf_len == 1)
+			    buf_len == 1 && !(flags & I2C_M_RECV_LEN))
 				cmd |= BIT(9);
 
 			if (need_restart) {
···
 		dev->tx_buf = buf;
 		dev->tx_buf_len = buf_len;
 
-		if (buf_len > 0) {
+		/*
+		 * Because we don't know the buffer length in the
+		 * I2C_FUNC_SMBUS_BLOCK_DATA case, we can't stop
+		 * the transaction here.
+		 */
+		if (buf_len > 0 || flags & I2C_M_RECV_LEN) {
 			/* more bytes to be written */
 			dev->status |= STATUS_WRITE_IN_PROGRESS;
 			break;
···
 		intr_mask = 0;
 
 	dw_writel(dev, intr_mask,  DW_IC_INTR_MASK);
+}
+
+static u8
+i2c_dw_recv_len(struct dw_i2c_dev *dev, u8 len)
+{
+	struct i2c_msg *msgs = dev->msgs;
+	u32 flags = msgs[dev->msg_read_idx].flags;
+
+	/*
+	 * Adjust the buffer length and mask the flag
+	 * after receiving the first byte.
+	 */
+	len += (flags & I2C_CLIENT_PEC) ? 2 : 1;
+	dev->tx_buf_len = len - min_t(u8, len, dev->rx_outstanding);
+	msgs[dev->msg_read_idx].len = len;
+	msgs[dev->msg_read_idx].flags &= ~I2C_M_RECV_LEN;
+
+	return len;
 }
 
 static void
···
 		rx_valid = dw_readl(dev, DW_IC_RXFLR);
 
 		for (; len > 0 && rx_valid > 0; len--, rx_valid--) {
-			*buf++ = dw_readl(dev, DW_IC_DATA_CMD);
+			u32 flags = msgs[dev->msg_read_idx].flags;
+
+			*buf = dw_readl(dev, DW_IC_DATA_CMD);
+			/* Ensure length byte is a valid value */
+			if (flags & I2C_M_RECV_LEN &&
+				*buf <= I2C_SMBUS_BLOCK_MAX && *buf > 0) {
+				len = i2c_dw_recv_len(dev, *buf);
+			}
+			buf++;
 			dev->rx_outstanding--;
 		}
 

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

···
  *
  */
 
+#include <linux/i2c.h>
+
+#define DW_IC_DEFAULT_FUNCTIONALITY (I2C_FUNC_I2C |			\
+					I2C_FUNC_SMBUS_BYTE |		\
+					I2C_FUNC_SMBUS_BYTE_DATA |	\
+					I2C_FUNC_SMBUS_WORD_DATA |	\
+					I2C_FUNC_SMBUS_BLOCK_DATA |	\
+					I2C_FUNC_SMBUS_I2C_BLOCK)
 
 #define DW_IC_CON_MASTER		0x1
 #define DW_IC_CON_SPEED_STD		0x2

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

···
 				DW_IC_CON_SLAVE_DISABLE |	\
 				DW_IC_CON_RESTART_EN)
 
-#define DW_DEFAULT_FUNCTIONALITY (I2C_FUNC_I2C |			\
-					I2C_FUNC_SMBUS_BYTE |		\
-					I2C_FUNC_SMBUS_BYTE_DATA |	\
-					I2C_FUNC_SMBUS_WORD_DATA |	\
-					I2C_FUNC_SMBUS_I2C_BLOCK)
-
 /* Merrifield HCNT/LCNT/SDA hold time */
 static struct dw_scl_sda_cfg mrfld_config = {
 	.ss_hcnt = 0x2f8,
···
 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
 		.tx_fifo_depth = 32,
 		.rx_fifo_depth = 32,
+		.functionality = I2C_FUNC_10BIT_ADDR,
 		.clk_khz      = 25000,
 		.setup = mfld_setup,
 	},
···
 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
 		.tx_fifo_depth = 64,
 		.rx_fifo_depth = 64,
+		.functionality = I2C_FUNC_10BIT_ADDR,
 		.scl_sda_cfg = &mrfld_config,
 		.setup = mrfld_setup,
 	},
···
 	}
 
 	dev->functionality = controller->functionality |
-				DW_DEFAULT_FUNCTIONALITY;
+				DW_IC_DEFAULT_FUNCTIONALITY;
 
 	dev->master_cfg = controller->bus_cfg;
 	if (controller->scl_sda_cfg) {

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

···
 	dev->irq = irq;
 	platform_set_drvdata(pdev, dev);
 
-	/* fast mode by default because of legacy reasons */
-	dev->clk_freq = 400000;
-
 	if (pdata) {
 		dev->clk_freq = pdata->i2c_scl_freq;
 	} else {
···
 	}
 
 	acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev);
-	if (acpi_speed)
-		dev->clk_freq = acpi_speed;
+	/*
+	 * Find bus speed from the "clock-frequency" device property, ACPI
+	 * or by using fast mode if neither is set.
+	 */
+	if (acpi_speed && dev->clk_freq)
+		dev->clk_freq = min(dev->clk_freq, acpi_speed);
+	else if (acpi_speed || dev->clk_freq)
+		dev->clk_freq = max(dev->clk_freq, acpi_speed);
+	else
+		dev->clk_freq = 400000;
 
 	if (has_acpi_companion(&pdev->dev))
 		dw_i2c_acpi_configure(pdev);
···
 	if (r)
 		return r;
 
-	dev->functionality =
-		I2C_FUNC_I2C |
-		I2C_FUNC_10BIT_ADDR |
-		I2C_FUNC_SMBUS_BYTE |
-		I2C_FUNC_SMBUS_BYTE_DATA |
-		I2C_FUNC_SMBUS_WORD_DATA |
-		I2C_FUNC_SMBUS_I2C_BLOCK;
+	dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY;
 
 	dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
 			  DW_IC_CON_RESTART_EN;

drivers/i2c/busses/i2c-dln2.c

···
 	.functionality = dln2_i2c_func,
 };
 
-static struct i2c_adapter_quirks dln2_i2c_quirks = {
+static const struct i2c_adapter_quirks dln2_i2c_quirks = {
 	.max_read_len = DLN2_I2C_MAX_XFER_SIZE,
 	.max_write_len = DLN2_I2C_MAX_XFER_SIZE,
 };

drivers/i2c/busses/i2c-i801.c

···
 #define SMBSLVSTS(p)	(16 + (p)->smba)	/* ICH3 and later */
 #define SMBSLVCMD(p)	(17 + (p)->smba)	/* ICH3 and later */
 #define SMBNTFDADD(p)	(20 + (p)->smba)	/* ICH3 and later */
-#define SMBNTFDDAT(p)	(22 + (p)->smba)	/* ICH3 and later */
 
 /* PCI Address Constants */
 #define SMBBAR		4
···
 #define SBREG_SMBCTRL		0xc6000c
 
 /* Host status bits for SMBPCISTS */
-#define SMBPCISTS_INTS		0x08
+#define SMBPCISTS_INTS		BIT(3)
 
 /* Control bits for SMBPCICTL */
-#define SMBPCICTL_INTDIS	0x0400
+#define SMBPCICTL_INTDIS	BIT(10)
 
 /* Host configuration bits for SMBHSTCFG */
-#define SMBHSTCFG_HST_EN	1
-#define SMBHSTCFG_SMB_SMI_EN	2
-#define SMBHSTCFG_I2C_EN	4
-#define SMBHSTCFG_SPD_WD	0x10
+#define SMBHSTCFG_HST_EN	BIT(0)
+#define SMBHSTCFG_SMB_SMI_EN	BIT(1)
+#define SMBHSTCFG_I2C_EN	BIT(2)
+#define SMBHSTCFG_SPD_WD	BIT(4)
 
 /* TCO configuration bits for TCOCTL */
-#define TCOCTL_EN		0x0100
+#define TCOCTL_EN		BIT(8)
 
 /* Auxiliary status register bits, ICH4+ only */
-#define SMBAUXSTS_CRCE		1
-#define SMBAUXSTS_STCO		2
+#define SMBAUXSTS_CRCE		BIT(0)
+#define SMBAUXSTS_STCO		BIT(1)
 
 /* Auxiliary control register bits, ICH4+ only */
-#define SMBAUXCTL_CRC		1
-#define SMBAUXCTL_E32B		2
+#define SMBAUXCTL_CRC		BIT(0)
+#define SMBAUXCTL_E32B		BIT(1)
 
 /* Other settings */
 #define MAX_RETRIES		400
···
 #define I801_I2C_BLOCK_DATA	0x18	/* ICH5 and later */
 
 /* I801 Host Control register bits */
-#define SMBHSTCNT_INTREN	0x01
-#define SMBHSTCNT_KILL		0x02
-#define SMBHSTCNT_LAST_BYTE	0x20
-#define SMBHSTCNT_START		0x40
-#define SMBHSTCNT_PEC_EN	0x80	/* ICH3 and later */
+#define SMBHSTCNT_INTREN	BIT(0)
+#define SMBHSTCNT_KILL		BIT(1)
+#define SMBHSTCNT_LAST_BYTE	BIT(5)
+#define SMBHSTCNT_START		BIT(6)
+#define SMBHSTCNT_PEC_EN	BIT(7)	/* ICH3 and later */
 
 /* I801 Hosts Status register bits */
-#define SMBHSTSTS_BYTE_DONE	0x80
-#define SMBHSTSTS_INUSE_STS	0x40
-#define SMBHSTSTS_SMBALERT_STS	0x20
-#define SMBHSTSTS_FAILED	0x10
-#define SMBHSTSTS_BUS_ERR	0x08
-#define SMBHSTSTS_DEV_ERR	0x04
-#define SMBHSTSTS_INTR		0x02
-#define SMBHSTSTS_HOST_BUSY	0x01
+#define SMBHSTSTS_BYTE_DONE	BIT(7)
+#define SMBHSTSTS_INUSE_STS	BIT(6)
+#define SMBHSTSTS_SMBALERT_STS	BIT(5)
+#define SMBHSTSTS_FAILED	BIT(4)
+#define SMBHSTSTS_BUS_ERR	BIT(3)
+#define SMBHSTSTS_DEV_ERR	BIT(2)
+#define SMBHSTSTS_INTR		BIT(1)
+#define SMBHSTSTS_HOST_BUSY	BIT(0)
 
-/* Host Notify Status registers bits */
-#define SMBSLVSTS_HST_NTFY_STS	1
+/* Host Notify Status register bits */
+#define SMBSLVSTS_HST_NTFY_STS	BIT(0)
 
-/* Host Notify Command registers bits */
-#define SMBSLVCMD_HST_NTFY_INTREN	0x01
+/* Host Notify Command register bits */
+#define SMBSLVCMD_HST_NTFY_INTREN	BIT(0)
 
 #define STATUS_ERROR_FLAGS	(SMBHSTSTS_FAILED | SMBHSTSTS_BUS_ERR | \
 				 SMBHSTSTS_DEV_ERR)
···
 	struct i2c_adapter adapter;
 	unsigned long smba;
 	unsigned char original_hstcfg;
+	unsigned char original_slvcmd;
 	struct pci_dev *pci_dev;
 	unsigned int features;
 
···
 	 */
 	bool acpi_reserved;
 	struct mutex acpi_lock;
-	struct smbus_host_notify *host_notify;
 };
 
-#define SMBHSTNTFY_SIZE		8
-
-#define FEATURE_SMBUS_PEC	(1 << 0)
-#define FEATURE_BLOCK_BUFFER	(1 << 1)
-#define FEATURE_BLOCK_PROC	(1 << 2)
-#define FEATURE_I2C_BLOCK_READ	(1 << 3)
-#define FEATURE_IRQ		(1 << 4)
-#define FEATURE_HOST_NOTIFY	(1 << 5)
+#define FEATURE_SMBUS_PEC	BIT(0)
+#define FEATURE_BLOCK_BUFFER	BIT(1)
+#define FEATURE_BLOCK_PROC	BIT(2)
+#define FEATURE_I2C_BLOCK_READ	BIT(3)
+#define FEATURE_IRQ		BIT(4)
+#define FEATURE_HOST_NOTIFY	BIT(5)
 /* Not really a feature, but it's convenient to handle it as such */
-#define FEATURE_IDF		(1 << 15)
-#define FEATURE_TCO		(1 << 16)
+#define FEATURE_IDF		BIT(15)
+#define FEATURE_TCO		BIT(16)
 
 static const char *i801_feature_names[] = {
 	"SMBus PEC",
···
 static irqreturn_t i801_host_notify_isr(struct i801_priv *priv)
 {
 	unsigned short addr;
-	unsigned int data;
 
 	addr = inb_p(SMBNTFDADD(priv)) >> 1;
-	data = inw_p(SMBNTFDDAT(priv));
 
-	i2c_handle_smbus_host_notify(priv->host_notify, addr, data);
+	/*
+	 * With the tested platforms, reading SMBNTFDDAT (22 + (p)->smba)
+	 * always returns 0. Our current implementation doesn't provide
+	 * data, so we just ignore it.
+	 */
+	i2c_handle_smbus_host_notify(&priv->adapter, addr);
 
 	/* clear Host Notify bit and return */
 	outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv));
···
 		I2C_FUNC_SMBUS_HOST_NOTIFY : 0);
 }
 
-static int i801_enable_host_notify(struct i2c_adapter *adapter)
+static void i801_enable_host_notify(struct i2c_adapter *adapter)
 {
 	struct i801_priv *priv = i2c_get_adapdata(adapter);
 
 	if (!(priv->features & FEATURE_HOST_NOTIFY))
-		return -ENOTSUPP;
+		return;
 
-	if (!priv->host_notify)
-		priv->host_notify = i2c_setup_smbus_host_notify(adapter);
-	if (!priv->host_notify)
-		return -ENOMEM;
+	priv->original_slvcmd = inb_p(SMBSLVCMD(priv));
 
-	outb_p(SMBSLVCMD_HST_NTFY_INTREN, SMBSLVCMD(priv));
+	if (!(SMBSLVCMD_HST_NTFY_INTREN & priv->original_slvcmd))
+		outb_p(SMBSLVCMD_HST_NTFY_INTREN | priv->original_slvcmd,
+		       SMBSLVCMD(priv));
+
 	/* clear Host Notify bit to allow a new notification */
 	outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv));
+}
 
-	return 0;
+static void i801_disable_host_notify(struct i801_priv *priv)
+{
+	if (!(priv->features & FEATURE_HOST_NOTIFY))
+		return;
+
+	outb_p(priv->original_slvcmd, SMBSLVCMD(priv));
 }
 
 static const struct i2c_algorithm smbus_algorithm = {
···
 		return err;
 	}
 
-	/*
-	 * Enable Host Notify for chips that supports it.
-	 * It is done after i2c_add_adapter() so that we are sure the work queue
-	 * is not used if i2c_add_adapter() fails.
-	 */
-	err = i801_enable_host_notify(&priv->adapter);
-	if (err && err != -ENOTSUPP)
-		dev_warn(&dev->dev, "Unable to enable SMBus Host Notify\n");
+	i801_enable_host_notify(&priv->adapter);
 
 	i801_probe_optional_slaves(priv);
 	/* We ignore errors - multiplexing is optional */
···
 	pm_runtime_forbid(&dev->dev);
 	pm_runtime_get_noresume(&dev->dev);
 
+	i801_disable_host_notify(priv);
 	i801_del_mux(priv);
 	i2c_del_adapter(&priv->adapter);
 	i801_acpi_remove(priv);
···
 {
 	struct pci_dev *pci_dev = to_pci_dev(dev);
 	struct i801_priv *priv = pci_get_drvdata(pci_dev);
-	int err;
 
-	err = i801_enable_host_notify(&priv->adapter);
-	if (err && err != -ENOTSUPP)
-		dev_warn(dev, "Unable to enable SMBus Host Notify\n");
+	i801_enable_host_notify(&priv->adapter);
 
 	return 0;
 }

drivers/i2c/busses/i2c-imx-lpi2c.c

···
+/*
+ * This is i.MX low power i2c controller driver.
+ *
+ * Copyright 2016 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#define DRIVER_NAME "imx-lpi2c"
+
+#define LPI2C_PARAM	0x04	/* i2c RX/TX FIFO size */
+#define LPI2C_MCR	0x10	/* i2c contrl register */
+#define LPI2C_MSR	0x14	/* i2c status register */
+#define LPI2C_MIER	0x18	/* i2c interrupt enable */
+#define LPI2C_MCFGR0	0x20	/* i2c master configuration */
+#define LPI2C_MCFGR1	0x24	/* i2c master configuration */
+#define LPI2C_MCFGR2	0x28	/* i2c master configuration */
+#define LPI2C_MCFGR3	0x2C	/* i2c master configuration */
+#define LPI2C_MCCR0	0x48	/* i2c master clk configuration */
+#define LPI2C_MCCR1	0x50	/* i2c master clk configuration */
+#define LPI2C_MFCR	0x58	/* i2c master FIFO control */
+#define LPI2C_MFSR	0x5C	/* i2c master FIFO status */
+#define LPI2C_MTDR	0x60	/* i2c master TX data register */
+#define LPI2C_MRDR	0x70	/* i2c master RX data register */
+
+/* i2c command */
+#define TRAN_DATA	0X00
+#define RECV_DATA	0X01
+#define GEN_STOP	0X02
+#define RECV_DISCARD	0X03
+#define GEN_START	0X04
+#define START_NACK	0X05
+#define START_HIGH	0X06
+#define START_HIGH_NACK	0X07
+
+#define MCR_MEN		BIT(0)
+#define MCR_RST		BIT(1)
+#define MCR_DOZEN	BIT(2)
+#define MCR_DBGEN	BIT(3)
+#define MCR_RTF		BIT(8)
+#define MCR_RRF		BIT(9)
+#define MSR_TDF		BIT(0)
+#define MSR_RDF		BIT(1)
+#define MSR_SDF		BIT(9)
+#define MSR_NDF		BIT(10)
+#define MSR_ALF		BIT(11)
+#define MSR_MBF		BIT(24)
+#define MSR_BBF		BIT(25)
+#define MIER_TDIE	BIT(0)
+#define MIER_RDIE	BIT(1)
+#define MIER_SDIE	BIT(9)
+#define MIER_NDIE	BIT(10)
+#define MCFGR1_AUTOSTOP	BIT(8)
+#define MCFGR1_IGNACK	BIT(9)
+#define MRDR_RXEMPTY	BIT(14)
+
+#define I2C_CLK_RATIO	2
+#define CHUNK_DATA	256
+
+#define LPI2C_DEFAULT_RATE	100000
+#define STARDARD_MAX_BITRATE	400000
+#define FAST_MAX_BITRATE	1000000
+#define FAST_PLUS_MAX_BITRATE	3400000
+#define HIGHSPEED_MAX_BITRATE	5000000
+
+enum lpi2c_imx_mode {
+	STANDARD,	/* 100+Kbps */
+	FAST,		/* 400+Kbps */
+	FAST_PLUS,	/* 1.0+Mbps */
+	HS,		/* 3.4+Mbps */
+	ULTRA_FAST,	/* 5.0+Mbps */
+};
+
+enum lpi2c_imx_pincfg {
+	TWO_PIN_OD,
+	TWO_PIN_OO,
+	TWO_PIN_PP,
+	FOUR_PIN_PP,
+};
+
+struct lpi2c_imx_struct {
+	struct i2c_adapter	adapter;
+	struct clk		*clk;
+	void __iomem		*base;
+	__u8			*rx_buf;
+	__u8			*tx_buf;
+	struct completion	complete;
+	unsigned int		msglen;
+	unsigned int		delivered;
+	unsigned int		block_data;
+	unsigned int		bitrate;
+	unsigned int		txfifosize;
+	unsigned int		rxfifosize;
+	enum lpi2c_imx_mode	mode;
+};
+
+static void lpi2c_imx_intctrl(struct lpi2c_imx_struct *lpi2c_imx,
+			      unsigned int enable)
+{
+	writel(enable, lpi2c_imx->base + LPI2C_MIER);
+}
+
+static int lpi2c_imx_bus_busy(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	unsigned long orig_jiffies = jiffies;
+	unsigned int temp;
+
+	while (1) {
+		temp = readl(lpi2c_imx->base + LPI2C_MSR);
+
+		/* check for arbitration lost, clear if set */
+		if (temp & MSR_ALF) {
+			writel(temp, lpi2c_imx->base + LPI2C_MSR);
+			return -EAGAIN;
+		}
+
+		if (temp & (MSR_BBF | MSR_MBF))
+			break;
+
+		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
+			dev_dbg(&lpi2c_imx->adapter.dev, "bus not work\n");
+			return -ETIMEDOUT;
+		}
+		schedule();
+	}
+
+	return 0;
+}
+
+static void lpi2c_imx_set_mode(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	unsigned int bitrate = lpi2c_imx->bitrate;
+	enum lpi2c_imx_mode mode;
+
+	if (bitrate < STARDARD_MAX_BITRATE)
+		mode = STANDARD;
+	else if (bitrate < FAST_MAX_BITRATE)
+		mode = FAST;
+	else if (bitrate < FAST_PLUS_MAX_BITRATE)
+		mode = FAST_PLUS;
+	else if (bitrate < HIGHSPEED_MAX_BITRATE)
+		mode = HS;
+	else
+		mode = ULTRA_FAST;
+
+	lpi2c_imx->mode = mode;
+}
+
+static int lpi2c_imx_start(struct lpi2c_imx_struct *lpi2c_imx,
+			   struct i2c_msg *msgs)
+{
+	unsigned int temp;
+	u8 read;
+
+	temp = readl(lpi2c_imx->base + LPI2C_MCR);
+	temp |= MCR_RRF | MCR_RTF;
+	writel(temp, lpi2c_imx->base + LPI2C_MCR);
+	writel(0x7f00, lpi2c_imx->base + LPI2C_MSR);
+
+	read = msgs->flags & I2C_M_RD;
+	temp = (msgs->addr << 1 | read) | (GEN_START << 8);
+	writel(temp, lpi2c_imx->base + LPI2C_MTDR);
+
+	return lpi2c_imx_bus_busy(lpi2c_imx);
+}
+
+static void lpi2c_imx_stop(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	unsigned long orig_jiffies = jiffies;
+	unsigned int temp;
+
+	writel(GEN_STOP << 8, lpi2c_imx->base + LPI2C_MTDR);
+
+	do {
+		temp = readl(lpi2c_imx->base + LPI2C_MSR);
+		if (temp & MSR_SDF)
+			break;
+
+		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
+			dev_dbg(&lpi2c_imx->adapter.dev, "stop timeout\n");
+			break;
+		}
+		schedule();
+
+	} while (1);
+}
+
+/* CLKLO = I2C_CLK_RATIO * CLKHI, SETHOLD = CLKHI, DATAVD = CLKHI/2 */
+static int lpi2c_imx_config(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	u8 prescale, filt, sethold, clkhi, clklo, datavd;
+	unsigned int clk_rate, clk_cycle;
+	enum lpi2c_imx_pincfg pincfg;
+	unsigned int temp;
+
+	lpi2c_imx_set_mode(lpi2c_imx);
+
+	clk_rate = clk_get_rate(lpi2c_imx->clk);
+	if (lpi2c_imx->mode == HS || lpi2c_imx->mode == ULTRA_FAST)
+		filt = 0;
+	else
+		filt = 2;
+
+	for (prescale = 0; prescale <= 7; prescale++) {
+		clk_cycle = clk_rate / ((1 << prescale) * lpi2c_imx->bitrate)
+			    - 3 - (filt >> 1);
+		clkhi = (clk_cycle + I2C_CLK_RATIO) / (I2C_CLK_RATIO + 1);
+		clklo = clk_cycle - clkhi;
+		if (clklo < 64)
+			break;
+	}
+
+	if (prescale > 7)
+		return -EINVAL;
+
+	/* set MCFGR1: PINCFG, PRESCALE, IGNACK */
+	if (lpi2c_imx->mode == ULTRA_FAST)
+		pincfg = TWO_PIN_OO;
+	else
+		pincfg = TWO_PIN_OD;
+	temp = prescale | pincfg << 24;
+
+	if (lpi2c_imx->mode == ULTRA_FAST)
+		temp |= MCFGR1_IGNACK;
+
+	writel(temp, lpi2c_imx->base + LPI2C_MCFGR1);
+
+	/* set MCFGR2: FILTSDA, FILTSCL */
+	temp = (filt << 16) | (filt << 24);
+	writel(temp, lpi2c_imx->base + LPI2C_MCFGR2);
+
+	/* set MCCR: DATAVD, SETHOLD, CLKHI, CLKLO */
+	sethold = clkhi;
+	datavd = clkhi >> 1;
+	temp = datavd << 24 | sethold << 16 | clkhi << 8 | clklo;
+
+	if (lpi2c_imx->mode == HS)
+		writel(temp, lpi2c_imx->base + LPI2C_MCCR1);
+	else
+		writel(temp, lpi2c_imx->base + LPI2C_MCCR0);
+
+	return 0;
+}
+
+static int lpi2c_imx_master_enable(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	unsigned int temp;
+	int ret;
+
+	ret = clk_enable(lpi2c_imx->clk);
+	if (ret)
+		return ret;
+
+	temp = MCR_RST;
+	writel(temp, lpi2c_imx->base + LPI2C_MCR);
+	writel(0, lpi2c_imx->base + LPI2C_MCR);
+
+	ret = lpi2c_imx_config(lpi2c_imx);
+	if (ret)
+		goto clk_disable;
+
+	temp = readl(lpi2c_imx->base + LPI2C_MCR);
+	temp |= MCR_MEN;
+	writel(temp, lpi2c_imx->base + LPI2C_MCR);
+
+	return 0;
+
+clk_disable:
+	clk_disable(lpi2c_imx->clk);
+
+	return ret;
+}
+
+static int lpi2c_imx_master_disable(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	u32 temp;
+
+	temp = readl(lpi2c_imx->base + LPI2C_MCR);
+	temp &= ~MCR_MEN;
+	writel(temp, lpi2c_imx->base + LPI2C_MCR);
+
+	clk_disable(lpi2c_imx->clk);
+
+	return 0;
+}
+
+static int lpi2c_imx_msg_complete(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	unsigned long timeout;
+
+	timeout = wait_for_completion_timeout(&lpi2c_imx->complete, HZ);
+
+	return timeout ? 0 : -ETIMEDOUT;
+}
+
+static int lpi2c_imx_txfifo_empty(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	unsigned long orig_jiffies = jiffies;
+	u32 txcnt;
+
+	do {
+		txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
+
+		if (readl(lpi2c_imx->base + LPI2C_MSR) & MSR_NDF) {
+			dev_dbg(&lpi2c_imx->adapter.dev, "NDF detected\n");
+			return -EIO;
+		}
+
+		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
+			dev_dbg(&lpi2c_imx->adapter.dev, "txfifo empty timeout\n");
+			return -ETIMEDOUT;
+		}
+		schedule();
+
+	} while (txcnt);
+
+	return 0;
+}
+
+static void lpi2c_imx_set_tx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	writel(lpi2c_imx->txfifosize >> 1, lpi2c_imx->base + LPI2C_MFCR);
+}
+
+static void lpi2c_imx_set_rx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	unsigned int temp, remaining;
+
+	remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
+
+	if (remaining > (lpi2c_imx->rxfifosize >> 1))
+		temp = lpi2c_imx->rxfifosize >> 1;
+	else
+		temp = 0;
+
+	writel(temp << 16, lpi2c_imx->base + LPI2C_MFCR);
+}
+
+static void lpi2c_imx_write_txfifo(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	unsigned int data, txcnt;
+
+	txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
+
+	while (txcnt < lpi2c_imx->txfifosize) {
+		if (lpi2c_imx->delivered == lpi2c_imx->msglen)
+			break;
+
+		data = lpi2c_imx->tx_buf[lpi2c_imx->delivered++];
+		writel(data, lpi2c_imx->base + LPI2C_MTDR);
+		txcnt++;
+	}
+
+	if (lpi2c_imx->delivered < lpi2c_imx->msglen)
+		lpi2c_imx_intctrl(lpi2c_imx, MIER_TDIE | MIER_NDIE);
+	else
+		complete(&lpi2c_imx->complete);
+}
+
+static void lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct *lpi2c_imx)
+{
+	unsigned int blocklen, remaining;
+	unsigned int temp, data;
+
+	do {
+		data = readl(lpi2c_imx->base + LPI2C_MRDR);
+		if (data & MRDR_RXEMPTY)
+			break;
+
+		lpi2c_imx->rx_buf[lpi2c_imx->delivered++] = data & 0xff;
+	} while (1);
+
+	/*
+	 * First byte is the length of remaining packet in the SMBus block
+	 * data read. Add it to msgs->len.
+	 */
+	if (lpi2c_imx->block_data) {
+		blocklen = lpi2c_imx->rx_buf[0];
+		lpi2c_imx->msglen += blocklen;
+	}
+
+	remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
+
+	if (!remaining) {
+		complete(&lpi2c_imx->complete);
+		return;
+	}
+
+	/* not finished, still waiting for rx data */
+	lpi2c_imx_set_rx_watermark(lpi2c_imx);
+
+	/* multiple receive commands */
+	if (lpi2c_imx->block_data) {
+		lpi2c_imx->block_data = 0;
+		temp = remaining;
+		temp |= (RECV_DATA << 8);
+		writel(temp, lpi2c_imx->base + LPI2C_MTDR);
+	} else if (!(lpi2c_imx->delivered & 0xff)) {
+		temp = (remaining > CHUNK_DATA ? CHUNK_DATA : remaining) - 1;
+		temp |= (RECV_DATA << 8);
+		writel(temp, lpi2c_imx->base + LPI2C_MTDR);
+	}
+
+	lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE);
+}
+
+static void lpi2c_imx_write(struct lpi2c_imx_struct *lpi2c_imx,
+			    struct i2c_msg *msgs)
+{
+	lpi2c_imx->tx_buf = msgs->buf;
+	lpi2c_imx_set_tx_watermark(lpi2c_imx);
+	lpi2c_imx_write_txfifo(lpi2c_imx);
+}
+
+static void lpi2c_imx_read(struct lpi2c_imx_struct *lpi2c_imx,
+			   struct i2c_msg *msgs)
+{
+	unsigned int temp;
+
+	lpi2c_imx->rx_buf = msgs->buf;
+	lpi2c_imx->block_data = msgs->flags & I2C_M_RECV_LEN;
+
+	lpi2c_imx_set_rx_watermark(lpi2c_imx);
+	temp = msgs->len > CHUNK_DATA ? CHUNK_DATA - 1 : msgs->len - 1;
+	temp |= (RECV_DATA << 8);
+	writel(temp, lpi2c_imx->base + LPI2C_MTDR);
+
+	lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE | MIER_NDIE);
+}
+
+static int lpi2c_imx_xfer(struct i2c_adapter *adapter,
+			  struct i2c_msg *msgs, int num)
+{
+	struct lpi2c_imx_struct *lpi2c_imx = i2c_get_adapdata(adapter);
+	unsigned int temp;
+	int i, result;
+
+	result = lpi2c_imx_master_enable(lpi2c_imx);
+	if (result)
+		return result;
+
+	for (i = 0; i < num; i++) {
+		result = lpi2c_imx_start(lpi2c_imx, &msgs[i]);
+		if (result)
+			goto disable;
+
+		/* quick smbus */
+		if (num == 1 && msgs[0].len == 0)
+			goto stop;
+
+		lpi2c_imx->delivered = 0;
+		lpi2c_imx->msglen = msgs[i].len;
+		init_completion(&lpi2c_imx->complete);
+
+		if (msgs[i].flags & I2C_M_RD)
+			lpi2c_imx_read(lpi2c_imx, &msgs[i]);
+		else
+			lpi2c_imx_write(lpi2c_imx, &msgs[i]);
+
+		result = lpi2c_imx_msg_complete(lpi2c_imx);
+		if (result)
+			goto stop;
+
+		if (!(msgs[i].flags & I2C_M_RD)) {
+			result = lpi2c_imx_txfifo_empty(lpi2c_imx);
+			if (result)
+				goto stop;
+		}
+	}
+
+stop:
+	lpi2c_imx_stop(lpi2c_imx);
+
+	temp = readl(lpi2c_imx->base + LPI2C_MSR);
+	if ((temp & MSR_NDF) && !result)
+		result = -EIO;
+
+disable:
+	lpi2c_imx_master_disable(lpi2c_imx);
+
+	dev_dbg(&lpi2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
+		(result < 0) ? "error" : "success msg",
+		(result < 0) ? result : num);
+
+	return (result < 0) ? result : num;
+}
+
+static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id)
+{
+	struct lpi2c_imx_struct *lpi2c_imx = dev_id;
+	unsigned int temp;
+
+	lpi2c_imx_intctrl(lpi2c_imx, 0);
+	temp = readl(lpi2c_imx->base + LPI2C_MSR);
+
+	if (temp & MSR_RDF)
+		lpi2c_imx_read_rxfifo(lpi2c_imx);
+
+	if (temp & MSR_TDF)
+		lpi2c_imx_write_txfifo(lpi2c_imx);
+
+	if (temp & MSR_NDF)
+		complete(&lpi2c_imx->complete);
+
+	return IRQ_HANDLED;
+}
+
+static u32 lpi2c_imx_func(struct i2c_adapter *adapter)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
+		I2C_FUNC_SMBUS_READ_BLOCK_DATA;
+}
+
+static struct i2c_algorithm lpi2c_imx_algo = {
+	.master_xfer	= lpi2c_imx_xfer,
+	.functionality	= lpi2c_imx_func,
+};
+
+static const struct of_device_id lpi2c_imx_of_match[] = {
+	{ .compatible = "fsl,imx7ulp-lpi2c" },
+	{ .compatible = "fsl,imx8dv-lpi2c" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, lpi2c_imx_of_match);
+
+static int lpi2c_imx_probe(struct platform_device *pdev)
+{
+	struct lpi2c_imx_struct *lpi2c_imx;
+	struct resource *res;
+	unsigned int temp;
+	int irq, ret;
+
+	lpi2c_imx = devm_kzalloc(&pdev->dev, sizeof(*lpi2c_imx), GFP_KERNEL);
+	if (!lpi2c_imx)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	lpi2c_imx->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(lpi2c_imx->base))
+		return PTR_ERR(lpi2c_imx->base);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "can't get irq number\n");
+		return irq;
+	}
+
+	lpi2c_imx->adapter.owner	= THIS_MODULE;
+	lpi2c_imx->adapter.algo		= &lpi2c_imx_algo;
+	lpi2c_imx->adapter.dev.parent	= &pdev->dev;
+	lpi2c_imx->adapter.dev.of_node	= pdev->dev.of_node;
+	strlcpy(lpi2c_imx->adapter.name, pdev->name,
+		sizeof(lpi2c_imx->adapter.name));
+
+	lpi2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(lpi2c_imx->clk)) {
+		dev_err(&pdev->dev, "can't get I2C peripheral clock\n");
+		return PTR_ERR(lpi2c_imx->clk);
+	}
+
+	ret = of_property_read_u32(pdev->dev.of_node,
+				   "clock-frequency", &lpi2c_imx->bitrate);
+	if (ret)
+		lpi2c_imx->bitrate = LPI2C_DEFAULT_RATE;
+
+	ret = devm_request_irq(&pdev->dev, irq, lpi2c_imx_isr, 0,
+			       pdev->name, lpi2c_imx);
+	if (ret) {
+		dev_err(&pdev->dev, "can't claim irq %d\n", irq);
+		return ret;
+	}
+
+	i2c_set_adapdata(&lpi2c_imx->adapter, lpi2c_imx);
+	platform_set_drvdata(pdev, lpi2c_imx);
+
+	ret = clk_prepare_enable(lpi2c_imx->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "clk enable failed %d\n", ret);
+		return ret;
+	}
+
+	temp = readl(lpi2c_imx->base + LPI2C_PARAM);
+	lpi2c_imx->txfifosize = 1 << (temp & 0x0f);
+	lpi2c_imx->rxfifosize = 1 << ((temp >> 8) & 0x0f);
+
+	clk_disable(lpi2c_imx->clk);
+
+	ret = i2c_add_adapter(&lpi2c_imx->adapter);
+	if (ret)
+		goto clk_unprepare;
+
+	dev_info(&lpi2c_imx->adapter.dev, "LPI2C adapter registered\n");
+
+	return 0;
+
+clk_unprepare:
+	clk_unprepare(lpi2c_imx->clk);
+
+	return ret;
+}
+
+static int lpi2c_imx_remove(struct platform_device *pdev)
+{
+	struct lpi2c_imx_struct *lpi2c_imx = platform_get_drvdata(pdev);
+
+	i2c_del_adapter(&lpi2c_imx->adapter);
+
+	clk_unprepare(lpi2c_imx->clk);
+
+	return 0;
+}
+
+static struct platform_driver lpi2c_imx_driver = {
+	.probe = lpi2c_imx_probe,
+	.remove = lpi2c_imx_remove,
+	.driver = {
+		.name = DRIVER_NAME,
+		.of_match_table = lpi2c_imx_of_match,
+	},
+};
+
+module_platform_driver(lpi2c_imx_driver);
+
+MODULE_AUTHOR("Gao Pan <[e-mail]>");
+MODULE_DESCRIPTION("I2C adapter driver for LPI2C bus");
+MODULE_LICENSE("GPL");

drivers/i2c/busses/i2c-mlxcpld.c

···
+/*
+ * Copyright (c) 2016 Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2016 Michael Shych <[e-mail]>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+/* General defines */
+#define MLXPLAT_CPLD_LPC_I2C_BASE_ADDR	0x2000
+#define MLXCPLD_I2C_DEVICE_NAME		"i2c_mlxcpld"
+#define MLXCPLD_I2C_VALID_FLAG		(I2C_M_RECV_LEN | I2C_M_RD)
+#define MLXCPLD_I2C_BUS_NUM		1
+#define MLXCPLD_I2C_DATA_REG_SZ		36
+#define MLXCPLD_I2C_MAX_ADDR_LEN	4
+#define MLXCPLD_I2C_RETR_NUM		2
+#define MLXCPLD_I2C_XFER_TO		500000 /* usec */
+#define MLXCPLD_I2C_POLL_TIME		2000   /* usec */
+
+/* LPC I2C registers */
+#define MLXCPLD_LPCI2C_LPF_REG		0x0
+#define MLXCPLD_LPCI2C_CTRL_REG		0x1
+#define MLXCPLD_LPCI2C_HALF_CYC_REG	0x4
+#define MLXCPLD_LPCI2C_I2C_HOLD_REG	0x5
+#define MLXCPLD_LPCI2C_CMD_REG		0x6
+#define MLXCPLD_LPCI2C_NUM_DAT_REG	0x7
+#define MLXCPLD_LPCI2C_NUM_ADDR_REG	0x8
+#define MLXCPLD_LPCI2C_STATUS_REG	0x9
+#define MLXCPLD_LPCI2C_DATA_REG		0xa
+
+/* LPC I2C masks and parametres */
+#define MLXCPLD_LPCI2C_RST_SEL_MASK	0x1
+#define MLXCPLD_LPCI2C_TRANS_END	0x1
+#define MLXCPLD_LPCI2C_STATUS_NACK	0x10
+#define MLXCPLD_LPCI2C_NO_IND		0
+#define MLXCPLD_LPCI2C_ACK_IND		1
+#define MLXCPLD_LPCI2C_NACK_IND		2
+
+struct  mlxcpld_i2c_curr_xfer {
+	u8 cmd;
+	u8 addr_width;
+	u8 data_len;
+	u8 msg_num;
+	struct i2c_msg *msg;
+};
+
+struct mlxcpld_i2c_priv {
+	struct i2c_adapter adap;
+	u32 base_addr;
+	struct mutex lock;
+	struct  mlxcpld_i2c_curr_xfer xfer;
+	struct device *dev;
+};
+
+static void mlxcpld_i2c_lpc_write_buf(u8 *data, u8 len, u32 addr)
+{
+	int i;
+
+	for (i = 0; i < len - len % 4; i += 4)
+		outl(*(u32 *)(data + i), addr + i);
+	for (; i < len; ++i)
+		outb(*(data + i), addr + i);
+}
+
+static void mlxcpld_i2c_lpc_read_buf(u8 *data, u8 len, u32 addr)
+{
+	int i;
+
+	for (i = 0; i < len - len % 4; i += 4)
+		*(u32 *)(data + i) = inl(addr + i);
+	for (; i < len; ++i)
+		*(data + i) = inb(addr + i);
+}
+
+static void mlxcpld_i2c_read_comm(struct mlxcpld_i2c_priv *priv, u8 offs,
+				  u8 *data, u8 datalen)
+{
+	u32 addr = priv->base_addr + offs;
+
+	switch (datalen) {
+	case 1:
+		*(data) = inb(addr);
+		break;
+	case 2:
+		*((u16 *)data) = inw(addr);
+		break;
+	case 3:
+		*((u16 *)data) = inw(addr);
+		*(data + 2) = inb(addr + 2);
+		break;
+	case 4:
+		*((u32 *)data) = inl(addr);
+		break;
+	default:
+		mlxcpld_i2c_lpc_read_buf(data, datalen, addr);
+		break;
+	}
+}
+
+static void mlxcpld_i2c_write_comm(struct mlxcpld_i2c_priv *priv, u8 offs,
+				   u8 *data, u8 datalen)
+{
+	u32 addr = priv->base_addr + offs;
+
+	switch (datalen) {
+	case 1:
+		outb(*(data), addr);
+		break;
+	case 2:
+		outw(*((u16 *)data), addr);
+		break;
+	case 3:
+		outw(*((u16 *)data), addr);
+		outb(*(data + 2), addr + 2);
+		break;
+	case 4:
+		outl(*((u32 *)data), addr);
+		break;
+	default:
+		mlxcpld_i2c_lpc_write_buf(data, datalen, addr);
+		break;
+	}
+}
+
+/*
+ * Check validity of received i2c messages parameters.
+ * Returns 0 if OK, other - in case of invalid parameters.
+ */
+static int mlxcpld_i2c_check_msg_params(struct mlxcpld_i2c_priv *priv,
+					struct i2c_msg *msgs, int num)
+{
+	int i;
+
+	if (!num) {
+		dev_err(priv->dev, "Incorrect 0 num of messages\n");
+		return -EINVAL;
+	}
+
+	if (unlikely(msgs[0].addr > 0x7f)) {
+		dev_err(priv->dev, "Invalid address 0x%03x\n",
+			msgs[0].addr);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < num; ++i) {
+		if (unlikely(!msgs[i].buf)) {
+			dev_err(priv->dev, "Invalid buf in msg[%d]\n",
+				i);
+			return -EINVAL;
+		}
+		if (unlikely(msgs[0].addr != msgs[i].addr)) {
+			dev_err(priv->dev, "Invalid addr in msg[%d]\n",
+				i);
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Check if transfer is completed and status of operation.
+ * Returns 0 - transfer completed (both ACK or NACK),
+ * negative - transfer isn't finished.
+ */
+static int mlxcpld_i2c_check_status(struct mlxcpld_i2c_priv *priv, int *status)
+{
+	u8 val;
+
+	mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_STATUS_REG, &val, 1);
+
+	if (val & MLXCPLD_LPCI2C_TRANS_END) {
+		if (val & MLXCPLD_LPCI2C_STATUS_NACK)
+			/*
+			 * The slave is unable to accept the data. No such
+			 * slave, command not understood, or unable to accept
+			 * any more data.
+			 */
+			*status = MLXCPLD_LPCI2C_NACK_IND;
+		else
+			*status = MLXCPLD_LPCI2C_ACK_IND;
+		return 0;
+	}
+	*status = MLXCPLD_LPCI2C_NO_IND;
+
+	return -EIO;
+}
+
+static void mlxcpld_i2c_set_transf_data(struct mlxcpld_i2c_priv *priv,
+					struct i2c_msg *msgs, int num,
+					u8 comm_len)
+{
+	priv->xfer.msg = msgs;
+	priv->xfer.msg_num = num;
+
+	/*
+	 * All upper layers currently are never use transfer with more than
+	 * 2 messages. Actually, it's also not so relevant in Mellanox systems
+	 * because of HW limitation. Max size of transfer is not more than 32
+	 * bytes in the current x86 LPCI2C bridge.
+	 */
+	priv->xfer.cmd = msgs[num - 1].flags & I2C_M_RD;
+
+	if (priv->xfer.cmd == I2C_M_RD && comm_len != msgs[0].len) {
+		priv->xfer.addr_width = msgs[0].len;
+		priv->xfer.data_len = comm_len - priv->xfer.addr_width;
+	} else {
+		priv->xfer.addr_width = 0;
+		priv->xfer.data_len = comm_len;
+	}
+}
+
+/* Reset CPLD LPCI2C block */
+static void mlxcpld_i2c_reset(struct mlxcpld_i2c_priv *priv)
+{
+	u8 val;
+
+	mutex_lock(&priv->lock);
+
+	mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_CTRL_REG, &val, 1);
+	val &= ~MLXCPLD_LPCI2C_RST_SEL_MASK;
+	mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_CTRL_REG, &val, 1);
+
+	mutex_unlock(&priv->lock);
+}
+
+/* Make sure the CPLD is ready to start transmitting. */
+static int mlxcpld_i2c_check_busy(struct mlxcpld_i2c_priv *priv)
+{
+	u8 val;
+
+	mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_STATUS_REG, &val, 1);
+
+	if (val & MLXCPLD_LPCI2C_TRANS_END)
+		return 0;
+
+	return -EIO;
+}
+
+static int mlxcpld_i2c_wait_for_free(struct mlxcpld_i2c_priv *priv)
+{
+	int timeout = 0;
+
+	do {
+		if (!mlxcpld_i2c_check_busy(priv))
+			break;
+		usleep_range(MLXCPLD_I2C_POLL_TIME / 2, MLXCPLD_I2C_POLL_TIME);
+		timeout += MLXCPLD_I2C_POLL_TIME;
+	} while (timeout <= MLXCPLD_I2C_XFER_TO);
+
+	if (timeout > MLXCPLD_I2C_XFER_TO)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+/*
+ * Wait for master transfer to complete.
+ * It puts current process to sleep until we get interrupt or timeout expires.
+ * Returns the number of transferred or read bytes or error (<0).
+ */
+static int mlxcpld_i2c_wait_for_tc(struct mlxcpld_i2c_priv *priv)
+{
+	int status, i, timeout = 0;
+	u8 datalen;
+
+	do {
+		usleep_range(MLXCPLD_I2C_POLL_TIME / 2, MLXCPLD_I2C_POLL_TIME);
+		if (!mlxcpld_i2c_check_status(priv, &status))
+			break;
+		timeout += MLXCPLD_I2C_POLL_TIME;
+	} while (status == 0 && timeout < MLXCPLD_I2C_XFER_TO);
+
+	switch (status) {
+	case MLXCPLD_LPCI2C_NO_IND:
+		return -ETIMEDOUT;
+
+	case MLXCPLD_LPCI2C_ACK_IND:
+		if (priv->xfer.cmd != I2C_M_RD)
+			return (priv->xfer.addr_width + priv->xfer.data_len);
+
+		if (priv->xfer.msg_num == 1)
+			i = 0;
+		else
+			i = 1;
+
+		if (!priv->xfer.msg[i].buf)
+			return -EINVAL;
+
+		/*
+		 * Actual read data len will be always the same as
+		 * requested len. 0xff (line pull-up) will be returned
+		 * if slave has no data to return. Thus don't read
+		 * MLXCPLD_LPCI2C_NUM_DAT_REG reg from CPLD.
+		 */
+		datalen = priv->xfer.data_len;
+
+		mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_DATA_REG,
+				      priv->xfer.msg[i].buf, datalen);
+
+		return datalen;
+
+	case MLXCPLD_LPCI2C_NACK_IND:
+		return -ENXIO;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static void mlxcpld_i2c_xfer_msg(struct mlxcpld_i2c_priv *priv)
+{
+	int i, len = 0;
+	u8 cmd;
+
+	mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_NUM_DAT_REG,
+			       &priv->xfer.data_len, 1);
+	mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_NUM_ADDR_REG,
+			       &priv->xfer.addr_width, 1);
+
+	for (i = 0; i < priv->xfer.msg_num; i++) {
+		if ((priv->xfer.msg[i].flags & I2C_M_RD) != I2C_M_RD) {
+			/* Don't write to CPLD buffer in read transaction */
+			mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_DATA_REG +
+					       len, priv->xfer.msg[i].buf,
+					       priv->xfer.msg[i].len);
+			len += priv->xfer.msg[i].len;
+		}
+	}
+
+	/*
+	 * Set target slave address with command for master transfer.
+	 * It should be latest executed function before CPLD transaction.
+	 */
+	cmd = (priv->xfer.msg[0].addr << 1) | priv->xfer.cmd;
+	mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_CMD_REG, &cmd, 1);
+}
+
+/*
+ * Generic lpc-i2c transfer.
+ * Returns the number of processed messages or error (<0).
+ */
+static int mlxcpld_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
+			    int num)
+{
+	struct mlxcpld_i2c_priv *priv = i2c_get_adapdata(adap);
+	u8 comm_len = 0;
+	int i, err;
+
+	err = mlxcpld_i2c_check_msg_params(priv, msgs, num);
+	if (err) {
+		dev_err(priv->dev, "Incorrect message\n");
+		return err;
+	}
+
+	for (i = 0; i < num; ++i)
+		comm_len += msgs[i].len;
+
+	/* Check bus state */
+	if (mlxcpld_i2c_wait_for_free(priv)) {
+		dev_err(priv->dev, "LPCI2C bridge is busy\n");
+
+		/*
+		 * Usually it means something serious has happened.
+		 * We can not have unfinished previous transfer
+		 * so it doesn't make any sense to try to stop it.
+		 * Probably we were not able to recover from the
+		 * previous error.
+		 * The only reasonable thing - is soft reset.
+		 */
+		mlxcpld_i2c_reset(priv);
+		if (mlxcpld_i2c_check_busy(priv)) {
+			dev_err(priv->dev, "LPCI2C bridge is busy after reset\n");
+			return -EIO;
+		}
+	}
+
+	mlxcpld_i2c_set_transf_data(priv, msgs, num, comm_len);
+
+	mutex_lock(&priv->lock);
+
+	/* Do real transfer. Can't fail */
+	mlxcpld_i2c_xfer_msg(priv);
+
+	/* Wait for transaction complete */
+	err = mlxcpld_i2c_wait_for_tc(priv);
+
+	mutex_unlock(&priv->lock);
+
+	return err < 0 ? err : num;
+}
+
+static u32 mlxcpld_i2c_func(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA;
+}
+
+static const struct i2c_algorithm mlxcpld_i2c_algo = {
+	.master_xfer	= mlxcpld_i2c_xfer,
+	.functionality	= mlxcpld_i2c_func
+};
+
+static struct i2c_adapter_quirks mlxcpld_i2c_quirks = {
+	.flags = I2C_AQ_COMB_WRITE_THEN_READ,
+	.max_read_len = MLXCPLD_I2C_DATA_REG_SZ - MLXCPLD_I2C_MAX_ADDR_LEN,
+	.max_write_len = MLXCPLD_I2C_DATA_REG_SZ,
+	.max_comb_1st_msg_len = 4,
+};
+
+static struct i2c_adapter mlxcpld_i2c_adapter = {
+	.owner          = THIS_MODULE,
+	.name           = "i2c-mlxcpld",
+	.class          = I2C_CLASS_HWMON | I2C_CLASS_SPD,
+	.algo           = &mlxcpld_i2c_algo,
+	.quirks		= &mlxcpld_i2c_quirks,
+	.retries	= MLXCPLD_I2C_RETR_NUM,
+	.nr		= MLXCPLD_I2C_BUS_NUM,
+};
+
+static int mlxcpld_i2c_probe(struct platform_device *pdev)
+{
+	struct mlxcpld_i2c_priv *priv;
+	int err;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	mutex_init(&priv->lock);
+	platform_set_drvdata(pdev, priv);
+
+	priv->dev = &pdev->dev;
+
+	/* Register with i2c layer */
+	mlxcpld_i2c_adapter.timeout = usecs_to_jiffies(MLXCPLD_I2C_XFER_TO);
+	priv->adap = mlxcpld_i2c_adapter;
+	priv->adap.dev.parent = &pdev->dev;
+	priv->base_addr = MLXPLAT_CPLD_LPC_I2C_BASE_ADDR;
+	i2c_set_adapdata(&priv->adap, priv);
+
+	err = i2c_add_numbered_adapter(&priv->adap);
+	if (err)
+		mutex_destroy(&priv->lock);
+
+	return err;
+}
+
+static int mlxcpld_i2c_remove(struct platform_device *pdev)
+{
+	struct mlxcpld_i2c_priv *priv = platform_get_drvdata(pdev);
+
+	i2c_del_adapter(&priv->adap);
+	mutex_destroy(&priv->lock);
+
+	return 0;
+}
+
+static struct platform_driver mlxcpld_i2c_driver = {
+	.probe		= mlxcpld_i2c_probe,
+	.remove		= mlxcpld_i2c_remove,
+	.driver = {
+		.name = MLXCPLD_I2C_DEVICE_NAME,
+	},
+};
+
+module_platform_driver(mlxcpld_i2c_driver);
+
+MODULE_AUTHOR("Michael Shych <[e-mail]>");
+MODULE_DESCRIPTION("Mellanox I2C-CPLD controller driver");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS("platform:i2c-mlxcpld");

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

···
 	return (octeon_i2c_ctl_read(i2c) & TWSI_CTL_IFLG);
 }
 
-static bool octeon_i2c_test_ready(struct octeon_i2c *i2c, bool *first)
-{
-	if (octeon_i2c_test_iflg(i2c))
-		return true;
-
-	if (*first) {
-		*first = false;
-		return false;
-	}
-
-	/*
-	 * IRQ has signaled an event but IFLG hasn't changed.
-	 * Sleep and retry once.
-	 */
-	usleep_range(I2C_OCTEON_EVENT_WAIT, 2 * I2C_OCTEON_EVENT_WAIT);
-	return octeon_i2c_test_iflg(i2c);
-}
-
 /**
  * octeon_i2c_wait - wait for the IFLG to be set
  * @i2c: The struct octeon_i2c
···
 static int octeon_i2c_wait(struct octeon_i2c *i2c)
 {
 	long time_left;
-	bool first = true;
 
 	/*
 	 * Some chip revisions don't assert the irq in the interrupt
···
 	}
 
 	i2c->int_enable(i2c);
-	time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_ready(i2c, &first),
+	time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_iflg(i2c),
 				       i2c->adap.timeout);
 	i2c->int_disable(i2c);
 
···
 static bool octeon_i2c_hlc_test_valid(struct octeon_i2c *i2c)
 {
 	return (__raw_readq(i2c->twsi_base + SW_TWSI(i2c)) & SW_TWSI_V) == 0;
-}
-
-static bool octeon_i2c_hlc_test_ready(struct octeon_i2c *i2c, bool *first)
-{
-	/* check if valid bit is cleared */
-	if (octeon_i2c_hlc_test_valid(i2c))
-		return true;
-
-	if (*first) {
-		*first = false;
-		return false;
-	}
-
-	/*
-	 * IRQ has signaled an event but valid bit isn't cleared.
-	 * Sleep and retry once.
-	 */
-	usleep_range(I2C_OCTEON_EVENT_WAIT, 2 * I2C_OCTEON_EVENT_WAIT);
-	return octeon_i2c_hlc_test_valid(i2c);
 }
 
 static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c)
···
  */
 static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
 {
-	bool first = true;
 	int time_left;
 
 	/*
···
 
 	i2c->hlc_int_enable(i2c);
 	time_left = wait_event_timeout(i2c->queue,
-				       octeon_i2c_hlc_test_ready(i2c, &first),
+				       octeon_i2c_hlc_test_valid(i2c),
 				       i2c->adap.timeout);
 	i2c->hlc_int_disable(i2c);
 	if (!time_left)
···
 	struct octeon_i2c *i2c = i2c_get_adapdata(adap);
 
 	octeon_i2c_hlc_disable(i2c);
+	octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_RST, 0);
+	/* wait for software reset to settle */
+	udelay(5);
 
 	/*
 	 * Bring control register to a good state regardless

drivers/i2c/busses/i2c-pxa-pci.c

···
 /*
+ * CE4100 PCI-I2C glue code for PXA's driver
+ * Author: Sebastian Andrzej Siewior <[e-mail]>
+ * License: GPL v2
+ *
  * The CE4100's I2C device is more or less the same one as found on PXA.
  * It does not support slave mode, the register slightly moved. This PCI
  * device provides three bars, every contains a single I2C controller.
  */
-#include <linux/module.h>
+#include <linux/init.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/i2c/pxa-i2c.h>
···
 	return ret;
 }
 
-static void ce4100_i2c_remove(struct pci_dev *dev)
-{
-	struct ce4100_devices *sds;
-	unsigned int i;
-
-	sds = pci_get_drvdata(dev);
-
-	for (i = 0; i < ARRAY_SIZE(sds->pdev); i++)
-		platform_device_unregister(sds->pdev[i]);
-
-	pci_disable_device(dev);
-	kfree(sds);
-}
-
 static const struct pci_device_id ce4100_i2c_devices[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e68)},
 	{ },
 };
-MODULE_DEVICE_TABLE(pci, ce4100_i2c_devices);
 
 static struct pci_driver ce4100_i2c_driver = {
+	.driver = {
+		.suppress_bind_attrs = true,
+	},
 	.name           = "ce4100_i2c",
 	.id_table       = ce4100_i2c_devices,
 	.probe          = ce4100_i2c_probe,
-	.remove         = ce4100_i2c_remove,
 };
-
-module_pci_driver(ce4100_i2c_driver);
-
-MODULE_DESCRIPTION("CE4100 PCI-I2C glue code for PXA's driver");
-MODULE_LICENSE("GPL v2");
-MODULE_AUTHOR("Sebastian Andrzej Siewior <[e-mail]>");
+builtin_pci_driver(ce4100_i2c_driver);

drivers/i2c/busses/i2c-pxa.c

···
 	u32 isar;
 	u32 ilcr;
 	u32 iwcr;
+	u32 fm;
+	u32 hs;
 };
 
 enum pxa_i2c_types {
···
 	REGS_PXA3XX,
 	REGS_CE4100,
 	REGS_PXA910,
+	REGS_A3700,
 };
+
+#define ICR_BUSMODE_FM	(1 << 16)	   /* shifted fast mode for armada-3700 */
+#define ICR_BUSMODE_HS	(1 << 17)	   /* shifted high speed mode for armada-3700 */
 
 /*
  * I2C registers definitions
···
 		.ilcr = 0x28,
 		.iwcr = 0x30,
 	},
+	[REGS_A3700] = {
+		.ibmr =	0x00,
+		.idbr =	0x04,
+		.icr =	0x08,
+		.isr =	0x0c,
+		.isar =	0x10,
+		.fm = ICR_BUSMODE_FM,
+		.hs = ICR_BUSMODE_HS,
+	},
 };
 
 static const struct platform_device_id i2c_pxa_id_table[] = {
···
 	{ "pxa3xx-pwri2c",	REGS_PXA3XX },
 	{ "ce4100-i2c",		REGS_CE4100 },
 	{ "pxa910-i2c",		REGS_PXA910 },
+	{ "armada-3700-i2c",	REGS_A3700  },
 	{ },
 };
 MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
···
 	unsigned char		master_code;
 	unsigned long		rate;
 	bool			highmode_enter;
+	u32			fm_mask;
+	u32			hs_mask;
 };
 
 #define _IBMR(i2c)	((i2c)->reg_ibmr)
···
 		writel(i2c->slave_addr, _ISAR(i2c));
 
 	/* set control register values */
-	writel(I2C_ICR_INIT | (i2c->fast_mode ? ICR_FM : 0), _ICR(i2c));
-	writel(readl(_ICR(i2c)) | (i2c->high_mode ? ICR_HS : 0), _ICR(i2c));
+	writel(I2C_ICR_INIT | (i2c->fast_mode ? i2c->fm_mask : 0), _ICR(i2c));
+	writel(readl(_ICR(i2c)) | (i2c->high_mode ? i2c->hs_mask : 0), _ICR(i2c));
 
 #ifdef CONFIG_I2C_PXA_SLAVE
 	dev_info(&i2c->adap.dev, "Enabling slave mode\n");
···
 	{ .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX },
 	{ .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX },
 	{ .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA910 },
+	{ .compatible = "marvell,armada-3700-i2c", .data = (void *)REGS_A3700 },
 	{}
 };
 MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
···
 	i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr;
 	i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr;
 	i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr;
+	i2c->fm_mask = pxa_reg_layout[i2c_type].fm ? : ICR_FM;
+	i2c->hs_mask = pxa_reg_layout[i2c_type].hs ? : ICR_HS;
+
 	if (i2c_type != REGS_CE4100)
 		i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;
 

drivers/i2c/busses/i2c-qup.c

···
  *
  */
 
+#include <linux/acpi.h>
 #include <linux/atomic.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
···
 
 /* Max timeout in ms for 32k bytes */
 #define TOUT_MAX			300
+
+/* Default values. Use these if FW query fails */
+#define DEFAULT_CLK_FREQ 100000
+#define DEFAULT_SRC_CLK 20000000
 
 struct qup_i2c_block {
 	int	count;
···
 	return data_len;
 }
 
+static bool qup_i2c_check_msg_len(struct i2c_msg *msg)
+{
+	return ((msg->flags & I2C_M_RD) && (msg->flags & I2C_M_RECV_LEN));
+}
+
+static int qup_i2c_set_tags_smb(u16 addr, u8 *tags, struct qup_i2c_dev *qup,
+			struct i2c_msg *msg)
+{
+	int len = 0;
+
+	if (msg->len > 1) {
+		tags[len++] = QUP_TAG_V2_DATARD_STOP;
+		tags[len++] = qup_i2c_get_data_len(qup) - 1;
+	} else {
+		tags[len++] = QUP_TAG_V2_START;
+		tags[len++] = addr & 0xff;
+
+		if (msg->flags & I2C_M_TEN)
+			tags[len++] = addr >> 8;
+
+		tags[len++] = QUP_TAG_V2_DATARD;
+		/* Read 1 byte indicating the length of the SMBus message */
+		tags[len++] = 1;
+	}
+	return len;
+}
+
 static int qup_i2c_set_tags(u8 *tags, struct qup_i2c_dev *qup,
 			    struct i2c_msg *msg,  int is_dma)
 {
···
 	int data_len;
 
 	int last = (qup->blk.pos == (qup->blk.count - 1)) && (qup->is_last);
+
+	/* Handle tags for SMBus block read */
+	if (qup_i2c_check_msg_len(msg))
+		return qup_i2c_set_tags_smb(addr, tags, qup, msg);
 
 	if (qup->blk.pos == 0) {
 		tags[len++] = QUP_TAG_V2_START;
···
 				struct i2c_msg *msg)
 {
 	u32 val;
-	int idx, pos = 0, ret = 0, total;
+	int idx, pos = 0, ret = 0, total, msg_offset = 0;
 
+	/*
+	 * If the message length is already read in
+	 * the first byte of the buffer, account for
+	 * that by setting the offset
+	 */
+	if (qup_i2c_check_msg_len(msg) && (msg->len > 1))
+		msg_offset = 1;
 	total = qup_i2c_get_data_len(qup);
+	total -= msg_offset;
 
 	/* 2 extra bytes for read tags */
 	while (pos < (total + 2)) {
···
 
 			if (pos >= (total + 2))
 				goto out;
-
-			msg->buf[qup->pos++] = val & 0xff;
+			msg->buf[qup->pos + msg_offset] = val & 0xff;
+			qup->pos++;
 		}
 	}
 
···
 			goto err;
 
 		qup->blk.pos++;
+
+		/* Handle SMBus block read length */
+		if (qup_i2c_check_msg_len(msg) && (msg->len == 1)) {
+			if (msg->buf[0] > I2C_SMBUS_BLOCK_MAX) {
+				ret = -EPROTO;
+				goto err;
+			}
+			msg->len += msg->buf[0];
+			qup->pos = 0;
+			qup_i2c_set_blk_data(qup, msg);
+			/* set tag length for block read */
+			qup->blk.tx_tag_len = 2;
+			qup_i2c_set_read_mode_v2(qup, msg->buf[0]);
+		}
 	} while (qup->blk.pos < qup->blk.count);
 
 err:
···
 
 		if (qup_i2c_poll_state_i2c_master(qup)) {
 			ret = -EIO;
+			goto out;
+		}
+
+		if (qup_i2c_check_msg_len(&msgs[idx])) {
+			ret = -EINVAL;
 			goto out;
 		}
 
···
 static int qup_i2c_probe(struct platform_device *pdev)
 {
 	static const int blk_sizes[] = {4, 16, 32};
-	struct device_node *node = pdev->dev.of_node;
 	struct qup_i2c_dev *qup;
 	unsigned long one_bit_t;
 	struct resource *res;
 	u32 io_mode, hw_ver, size;
 	int ret, fs_div, hs_div;
-	int src_clk_freq;
-	u32 clk_freq = 100000;
+	u32 src_clk_freq = DEFAULT_SRC_CLK;
+	u32 clk_freq = DEFAULT_CLK_FREQ;
 	int blocks;
 
 	qup = devm_kzalloc(&pdev->dev, sizeof(*qup), GFP_KERNEL);
···
 	init_completion(&qup->xfer);
 	platform_set_drvdata(pdev, qup);
 
-	of_property_read_u32(node, "clock-frequency", &clk_freq);
+	ret = device_property_read_u32(qup->dev, "clock-frequency", &clk_freq);
+	if (ret) {
+		dev_notice(qup->dev, "using default clock-frequency %d",
+			DEFAULT_CLK_FREQ);
+	}
 
 	if (of_device_is_compatible(pdev->dev.of_node, "qcom,i2c-qup-v1.1.1")) {
 		qup->adap.algo = &qup_i2c_algo;
···
 		return qup->irq;
 	}
 
-	qup->clk = devm_clk_get(qup->dev, "core");
-	if (IS_ERR(qup->clk)) {
-		dev_err(qup->dev, "Could not get core clock\n");
-		return PTR_ERR(qup->clk);
-	}
+	if (has_acpi_companion(qup->dev)) {
+		ret = device_property_read_u32(qup->dev,
+				"src-clock-hz", &src_clk_freq);
+		if (ret) {
+			dev_notice(qup->dev, "using default src-clock-hz %d",
+				DEFAULT_SRC_CLK);
+		}
+		ACPI_COMPANION_SET(&qup->adap.dev, ACPI_COMPANION(qup->dev));
+	} else {
+		qup->clk = devm_clk_get(qup->dev, "core");
+		if (IS_ERR(qup->clk)) {
+			dev_err(qup->dev, "Could not get core clock\n");
+			return PTR_ERR(qup->clk);
+		}
 
-	qup->pclk = devm_clk_get(qup->dev, "iface");
-	if (IS_ERR(qup->pclk)) {
-		dev_err(qup->dev, "Could not get iface clock\n");
-		return PTR_ERR(qup->pclk);
+		qup->pclk = devm_clk_get(qup->dev, "iface");
+		if (IS_ERR(qup->pclk)) {
+			dev_err(qup->dev, "Could not get iface clock\n");
+			return PTR_ERR(qup->pclk);
+		}
+		qup_i2c_enable_clocks(qup);
+		src_clk_freq = clk_get_rate(qup->clk);
 	}
-
-	qup_i2c_enable_clocks(qup);
 
 	/*
 	 * Bootloaders might leave a pending interrupt on certain QUP's,
···
 	size = QUP_INPUT_FIFO_SIZE(io_mode);
 	qup->in_fifo_sz = qup->in_blk_sz * (2 << size);
 
-	src_clk_freq = clk_get_rate(qup->clk);
 	fs_div = ((src_clk_freq / clk_freq) / 2) - 3;
 	hs_div = 3;
 	qup->clk_ctl = (hs_div << 8) | (fs_div & 0xff);
···
 };
 MODULE_DEVICE_TABLE(of, qup_i2c_dt_match);
 
+#if IS_ENABLED(CONFIG_ACPI)
+static const struct acpi_device_id qup_i2c_acpi_match[] = {
+	{ "QCOM8010"},
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, qup_i2c_acpi_match);
+#endif
+
 static struct platform_driver qup_i2c_driver = {
 	.probe  = qup_i2c_probe,
 	.remove = qup_i2c_remove,
···
 		.name = "i2c_qup",
 		.pm = &qup_i2c_qup_pm_ops,
 		.of_match_table = qup_i2c_dt_match,
+		.acpi_match_table = ACPI_PTR(qup_i2c_acpi_match),
 	},
 };
 

drivers/i2c/busses/i2c-rcar.c

···
 };
 
 static const struct of_device_id rcar_i2c_dt_ids[] = {
-	{ .compatible = "renesas,i2c-rcar", .data = (void *)I2C_RCAR_GEN1 },
 	{ .compatible = "renesas,i2c-r8a7778", .data = (void *)I2C_RCAR_GEN1 },
 	{ .compatible = "renesas,i2c-r8a7779", .data = (void *)I2C_RCAR_GEN1 },
 	{ .compatible = "renesas,i2c-r8a7790", .data = (void *)I2C_RCAR_GEN2 },
···
 	{ .compatible = "renesas,i2c-r8a7794", .data = (void *)I2C_RCAR_GEN2 },
 	{ .compatible = "renesas,i2c-r8a7795", .data = (void *)I2C_RCAR_GEN3 },
 	{ .compatible = "renesas,i2c-r8a7796", .data = (void *)I2C_RCAR_GEN3 },
+	{ .compatible = "renesas,i2c-rcar", .data = (void *)I2C_RCAR_GEN1 },	/* Deprecated */
+	{ .compatible = "renesas,rcar-gen1-i2c", .data = (void *)I2C_RCAR_GEN1 },
+	{ .compatible = "renesas,rcar-gen2-i2c", .data = (void *)I2C_RCAR_GEN2 },
+	{ .compatible = "renesas,rcar-gen3-i2c", .data = (void *)I2C_RCAR_GEN3 },
 	{},
 };
 MODULE_DEVICE_TABLE(of, rcar_i2c_dt_ids);

drivers/i2c/busses/i2c-sh_mobile.c

···
 };
 
 static const struct of_device_id sh_mobile_i2c_dt_ids[] = {
-	{ .compatible = "renesas,rmobile-iic", .data = &default_dt_config },
 	{ .compatible = "renesas,iic-r8a73a4", .data = &fast_clock_dt_config },
 	{ .compatible = "renesas,iic-r8a7740", .data = &r8a7740_dt_config },
 	{ .compatible = "renesas,iic-r8a7790", .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-sh73a0", .data = &fast_clock_dt_config },
+	{ .compatible = "renesas,rmobile-iic", .data = &default_dt_config },
 	{},
 };
 MODULE_DEVICE_TABLE(of, sh_mobile_i2c_dt_ids);

drivers/i2c/busses/i2c-uniphier-f.c

···
 	if (!clk_rate) {
 		dev_err(dev, "input clock rate should not be zero\n");
 		ret = -EINVAL;
-		goto err;
+		goto disable_clk;
 	}
 
 	init_completion(&priv->comp);
···
 			       pdev->name, priv);
 	if (ret) {
 		dev_err(dev, "failed to request irq %d\n", irq);
-		goto err;
+		goto disable_clk;
 	}
 
 	ret = i2c_add_adapter(&priv->adap);
-err:
+disable_clk:
 	if (ret)
 		clk_disable_unprepare(priv->clk);
 

drivers/i2c/busses/i2c-uniphier.c

···
 	if (!clk_rate) {
 		dev_err(dev, "input clock rate should not be zero\n");
 		ret = -EINVAL;
-		goto err;
+		goto disable_clk;
 	}
 
 	init_completion(&priv->comp);
···
 			       priv);
 	if (ret) {
 		dev_err(dev, "failed to request irq %d\n", irq);
-		goto err;
+		goto disable_clk;
 	}
 
 	ret = i2c_add_adapter(&priv->adap);
-err:
+disable_clk:
 	if (ret)
 		clk_disable_unprepare(priv->clk);
 

drivers/i2c/busses/i2c-viperboard.c

···
 	.functionality	= vprbrd_i2c_func,
 };
 
-static struct i2c_adapter_quirks vprbrd_quirks = {
+static const struct i2c_adapter_quirks vprbrd_quirks = {
 	.max_read_len = 2048,
 	.max_write_len = 2048,
 };

drivers/i2c/busses/i2c-xlp9xx.c

···
 	init_completion(&priv->msg_complete);
 	priv->adapter.dev.parent = &pdev->dev;
 	priv->adapter.algo = &xlp9xx_i2c_algo;
+	ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&pdev->dev));
 	priv->adapter.dev.of_node = pdev->dev.of_node;
 	priv->dev = &pdev->dev;
 

drivers/i2c/i2c-core.c

···
 #define I2C_ADDR_OFFSET_TEN_BIT	0xa000
 #define I2C_ADDR_OFFSET_SLAVE	0x1000
 
+#define I2C_ADDR_7BITS_MAX	0x77
+#define I2C_ADDR_7BITS_COUNT	(I2C_ADDR_7BITS_MAX + 1)
+
 /* core_lock protects i2c_adapter_idr, and guarantees
    that device detection, deletion of detected devices, and attach_adapter
    calls are serialized */
···
 
 /* ------------------------------------------------------------------------- */
 
-static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
+const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
 						const struct i2c_client *client)
 {
+	if (!(id && client))
+		return NULL;
+
 	while (id->name[0]) {
 		if (strcmp(client->name, id->name) == 0)
 			return id;
···
 	}
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(i2c_match_id);
 
 static int i2c_device_match(struct device *dev, struct device_driver *drv)
 {
 	struct i2c_client	*client = i2c_verify_client(dev);
 	struct i2c_driver	*driver;
 
-	if (!client)
-		return 0;
 
 	/* Attempt an OF style match */
-	if (of_driver_match_device(dev, drv))
+	if (i2c_of_match_device(drv->of_match_table, client))
 		return 1;
 
 	/* Then ACPI style match */
···
 		return 1;
 
 	driver = to_i2c_driver(drv);
-	/* match on an id table if there is one */
-	if (driver->id_table)
-		return i2c_match_id(driver->id_table, client) != NULL;
+
+	/* Finally an I2C match */
+	if (i2c_match_id(driver->id_table, client))
+		return 1;
 
 	return 0;
 }
···
 	adap->bus_recovery_info = NULL;
 }
 
+static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client)
+{
+	struct i2c_adapter *adap = client->adapter;
+	unsigned int irq;
+
+	if (!adap->host_notify_domain)
+		return -ENXIO;
+
+	if (client->flags & I2C_CLIENT_TEN)
+		return -EINVAL;
+
+	irq = irq_find_mapping(adap->host_notify_domain, client->addr);
+	if (!irq)
+		irq = irq_create_mapping(adap->host_notify_domain,
+					 client->addr);
+
+	return irq > 0 ? irq : -ENXIO;
+}
+
 static int i2c_device_probe(struct device *dev)
 {
 	struct i2c_client	*client = i2c_verify_client(dev);
···
 		}
 		if (irq == -EPROBE_DEFER)
 			return irq;
+		/*
+		 * ACPI and OF did not find any useful IRQ, try to see
+		 * if Host Notify can be used.
+		 */
+		if (irq < 0) {
+			dev_dbg(dev, "Using Host Notify IRQ\n");
+			irq = i2c_smbus_host_notify_to_irq(client);
+		}
 		if (irq < 0)
 			irq = 0;
 
···
 	}
 
 	driver = to_i2c_driver(dev->driver);
-	if (!driver->probe || !driver->id_table)
+
+	/*
+	 * An I2C ID table is not mandatory, if and only if, a suitable Device
+	 * Tree match table entry is supplied for the probing device.
+	 */
+	if (!driver->id_table &&
+	    !i2c_of_match_device(dev->driver->of_match_table, client))
 		return -ENODEV;
 
 	if (client->flags & I2C_CLIENT_WAKE) {
···
 	if (status == -EPROBE_DEFER)
 		goto err_clear_wakeup_irq;
 
-	status = driver->probe(client, i2c_match_id(driver->id_table, client));
+	/*
+	 * When there are no more users of probe(),
+	 * rename probe_new to probe.
+	 */
+	if (driver->probe_new)
+		status = driver->probe_new(client);
+	else if (driver->probe)
+		status = driver->probe(client,
+				       i2c_match_id(driver->id_table, client));
+	else
+		status = -EINVAL;
+
 	if (status)
 		goto err_detach_pm_domain;
 
···
 	return adapter;
 }
 EXPORT_SYMBOL(of_get_i2c_adapter_by_node);
+
+static const struct of_device_id*
+i2c_of_match_device_sysfs(const struct of_device_id *matches,
+				  struct i2c_client *client)
+{
+	const char *name;
+
+	for (; matches->compatible[0]; matches++) {
+		/*
+		 * Adding devices through the i2c sysfs interface provides us
+		 * a string to match which may be compatible with the device
+		 * tree compatible strings, however with no actual of_node the
+		 * of_match_device() will not match
+		 */
+		if (sysfs_streq(client->name, matches->compatible))
+			return matches;
+
+		name = strchr(matches->compatible, ',');
+		if (!name)
+			name = matches->compatible;
+		else
+			name++;
+
+		if (sysfs_streq(client->name, name))
+			return matches;
+	}
+
+	return NULL;
+}
+
+const struct of_device_id
+*i2c_of_match_device(const struct of_device_id *matches,
+		     struct i2c_client *client)
+{
+	const struct of_device_id *match;
+
+	if (!(client && matches))
+		return NULL;
+
+	match = of_match_device(matches, &client->dev);
+	if (match)
+		return match;
+
+	return i2c_of_match_device_sysfs(matches, client);
+}
+EXPORT_SYMBOL_GPL(i2c_of_match_device);
 #else
 static void of_i2c_register_devices(struct i2c_adapter *adap) { }
 #endif /* CONFIG_OF */
···
 	.unlock_bus =  i2c_adapter_unlock_bus,
 };
 
+static void i2c_host_notify_irq_teardown(struct i2c_adapter *adap)
+{
+	struct irq_domain *domain = adap->host_notify_domain;
+	irq_hw_number_t hwirq;
+
+	if (!domain)
+		return;
+
+	for (hwirq = 0 ; hwirq < I2C_ADDR_7BITS_COUNT ; hwirq++)
+		irq_dispose_mapping(irq_find_mapping(domain, hwirq));
+
+	irq_domain_remove(domain);
+	adap->host_notify_domain = NULL;
+}
+
+static int i2c_host_notify_irq_map(struct irq_domain *h,
+					  unsigned int virq,
+					  irq_hw_number_t hw_irq_num)
+{
+	irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq);
+
+	return 0;
+}
+
+static const struct irq_domain_ops i2c_host_notify_irq_ops = {
+	.map = i2c_host_notify_irq_map,
+};
+
+static int i2c_setup_host_notify_irq_domain(struct i2c_adapter *adap)
+{
+	struct irq_domain *domain;
+
+	if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_HOST_NOTIFY))
+		return 0;
+
+	domain = irq_domain_create_linear(adap->dev.fwnode,
+					  I2C_ADDR_7BITS_COUNT,
+					  &i2c_host_notify_irq_ops, adap);
+	if (!domain)
+		return -ENOMEM;
+
+	adap->host_notify_domain = domain;
+
+	return 0;
+}
+
+/**
+ * i2c_handle_smbus_host_notify - Forward a Host Notify event to the correct
+ * I2C client.
+ * @adap: the adapter
+ * @addr: the I2C address of the notifying device
+ * Context: can't sleep
+ *
+ * Helper function to be called from an I2C bus driver's interrupt
+ * handler. It will schedule the Host Notify IRQ.
+ */
+int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr)
+{
+	int irq;
+
+	if (!adap)
+		return -EINVAL;
+
+	irq = irq_find_mapping(adap->host_notify_domain, addr);
+	if (irq <= 0)
+		return -ENXIO;
+
+	generic_handle_irq(irq);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(i2c_handle_smbus_host_notify);
+
 static int i2c_register_adapter(struct i2c_adapter *adap)
 {
 	int res = -EINVAL;
···
 	/* Set default timeout to 1 second if not already set */
 	if (adap->timeout == 0)
 		adap->timeout = HZ;
+
+	/* register soft irqs for Host Notify */
+	res = i2c_setup_host_notify_irq_domain(adap);
+	if (res) {
+		pr_err("adapter '%s': can't create Host Notify IRQs (%d)\n",
+		       adap->name, res);
+		goto out_list;
+	}
 
 	dev_set_name(&adap->dev, "i2c-%d", adap->nr);
 	adap->dev.bus = &i2c_bus_type;
···
 	dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name);
 
 	pm_runtime_disable(&adap->dev);
+
+	i2c_host_notify_irq_teardown(adap);
 
 	/* wait until all references to the device are gone
 	 *

drivers/i2c/i2c-smbus.c

···
 }
 EXPORT_SYMBOL_GPL(i2c_handle_smbus_alert);
 
-static void smbus_host_notify_work(struct work_struct *work)
-{
-	struct alert_data alert;
-	struct i2c_adapter *adapter;
-	unsigned long flags;
-	u16 payload;
-	u8 addr;
-	struct smbus_host_notify *data;
-
-	data = container_of(work, struct smbus_host_notify, work);
-
-	spin_lock_irqsave(&data->lock, flags);
-	payload = data->payload;
-	addr = data->addr;
-	adapter = data->adapter;
-
-	/* clear the pending bit and release the spinlock */
-	data->pending = false;
-	spin_unlock_irqrestore(&data->lock, flags);
-
-	if (!adapter || !addr)
-		return;
-
-	alert.type = I2C_PROTOCOL_SMBUS_HOST_NOTIFY;
-	alert.addr = addr;
-	alert.data = payload;
-
-	device_for_each_child(&adapter->dev, &alert, smbus_do_alert);
-}
-
-/**
- * i2c_setup_smbus_host_notify - Allocate a new smbus_host_notify for the given
- * I2C adapter.
- * @adapter: the adapter we want to associate a Host Notify function
- *
- * Returns a struct smbus_host_notify pointer on success, and NULL on failure.
- * The resulting smbus_host_notify must not be freed afterwards, it is a
- * managed resource already.
- */
-struct smbus_host_notify *i2c_setup_smbus_host_notify(struct i2c_adapter *adap)
-{
-	struct smbus_host_notify *host_notify;
-
-	host_notify = devm_kzalloc(&adap->dev, sizeof(struct smbus_host_notify),
-				   GFP_KERNEL);
-	if (!host_notify)
-		return NULL;
-
-	host_notify->adapter = adap;
-
-	spin_lock_init(&host_notify->lock);
-	INIT_WORK(&host_notify->work, smbus_host_notify_work);
-
-	return host_notify;
-}
-EXPORT_SYMBOL_GPL(i2c_setup_smbus_host_notify);
-
-/**
- * i2c_handle_smbus_host_notify - Forward a Host Notify event to the correct
- * I2C client.
- * @host_notify: the struct host_notify attached to the relevant adapter
- * @addr: the I2C address of the notifying device
- * @data: the payload of the notification
- * Context: can't sleep
- *
- * Helper function to be called from an I2C bus driver's interrupt
- * handler. It will schedule the Host Notify work, in turn calling the
- * corresponding I2C device driver's alert function.
- *
- * host_notify should be a valid pointer previously returned by
- * i2c_setup_smbus_host_notify().
- */
-int i2c_handle_smbus_host_notify(struct smbus_host_notify *host_notify,
-				 unsigned short addr, unsigned int data)
-{
-	unsigned long flags;
-	struct i2c_adapter *adapter;
-
-	if (!host_notify || !host_notify->adapter)
-		return -EINVAL;
-
-	adapter = host_notify->adapter;
-
-	spin_lock_irqsave(&host_notify->lock, flags);
-
-	if (host_notify->pending) {
-		spin_unlock_irqrestore(&host_notify->lock, flags);
-		dev_warn(&adapter->dev, "Host Notify already scheduled.\n");
-		return -EBUSY;
-	}
-
-	host_notify->payload = data;
-	host_notify->addr = addr;
-
-	/* Mark that there is a pending notification and release the lock */
-	host_notify->pending = true;
-	spin_unlock_irqrestore(&host_notify->lock, flags);
-
-	return schedule_work(&host_notify->work);
-}
-EXPORT_SYMBOL_GPL(i2c_handle_smbus_host_notify);
-
 module_i2c_driver(smbalert_driver);
 
 MODULE_AUTHOR("Jean Delvare <[e-mail]>");

drivers/i2c/muxes/Kconfig

···
 	  demultiplexer that uses the pinctrl subsystem. This is useful if you
 	  want to change the I2C master at run-time depending on features.
 
+config I2C_MUX_MLXCPLD
+        tristate "Mellanox CPLD based I2C multiplexer"
+        help
+          If you say yes to this option, support will be included for a
+          CPLD based I2C multiplexer. This driver provides access to
+          I2C busses connected through a MUX, which is controlled
+          by a CPLD register.
+
+          This driver can also be built as a module.  If so, the module
+          will be called i2c-mux-mlxcpld.
+
 endmenu

drivers/i2c/muxes/Makefile

···
 obj-$(CONFIG_I2C_DEMUX_PINCTRL)		+= i2c-demux-pinctrl.o
 
 obj-$(CONFIG_I2C_MUX_GPIO)	+= i2c-mux-gpio.o
+obj-$(CONFIG_I2C_MUX_MLXCPLD)	+= i2c-mux-mlxcpld.o
 obj-$(CONFIG_I2C_MUX_PCA9541)	+= i2c-mux-pca9541.o
 obj-$(CONFIG_I2C_MUX_PCA954x)	+= i2c-mux-pca954x.o
 obj-$(CONFIG_I2C_MUX_PINCTRL)	+= i2c-mux-pinctrl.o

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

···
 struct gpiomux {
 	struct i2c_mux_gpio_platform_data data;
 	unsigned gpio_base;
+	struct gpio_desc **gpios;
+	int *values;
 };
 
 static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val)
···
 	int i;
 
 	for (i = 0; i < mux->data.n_gpios; i++)
-		gpio_set_value_cansleep(mux->gpio_base + mux->data.gpios[i],
-					val & (1 << i));
+		mux->values[i] = (val >> i) & 1;
+
+	gpiod_set_array_value_cansleep(mux->data.n_gpios,
+				       mux->gpios, mux->values);
 }
 
 static int i2c_mux_gpio_select(struct i2c_mux_core *muxc, u32 chan)
···
 	if (!parent)
 		return -EPROBE_DEFER;
 
-	muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values, 0, 0,
+	muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values,
+			     mux->data.n_gpios * sizeof(*mux->gpios) +
+			     mux->data.n_gpios * sizeof(*mux->values), 0,
 			     i2c_mux_gpio_select, NULL);
 	if (!muxc) {
 		ret = -ENOMEM;
 		goto alloc_failed;
 	}
+	mux->gpios = muxc->priv;
+	mux->values = (int *)(mux->gpios + mux->data.n_gpios);
 	muxc->priv = mux;
 
 	platform_set_drvdata(pdev, muxc);
···
 			goto err_request_gpio;
 		}
 
+		gpio_desc = gpio_to_desc(gpio_base + mux->data.gpios[i]);
+		mux->gpios[i] = gpio_desc;
+
 		if (!muxc->mux_locked)
 			continue;
 
-		gpio_desc = gpio_to_desc(gpio_base + mux->data.gpios[i]);
 		gpio_dev = &gpio_desc->gdev->dev;
 		muxc->mux_locked = i2c_root_adapter(gpio_dev) == root;
 	}

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

···
+/*
+ * drivers/i2c/muxes/i2c-mux-mlxcpld.c
+ * Copyright (c) 2016 Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2016 Michael Shych <[e-mail]>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/version.h>
+#include <linux/i2c/mlxcpld.h>
+
+#define CPLD_MUX_MAX_NCHANS	8
+
+/* mlxcpld_mux - mux control structure:
+ * @last_chan - last register value
+ * @client - I2C device client
+ */
+struct mlxcpld_mux {
+	u8 last_chan;
+	struct i2c_client *client;
+};
+
+/* MUX logic description.
+ * Driver can support different mux control logic, according to CPLD
+ * implementation.
+ *
+ * Connectivity schema.
+ *
+ * i2c-mlxcpld                                 Digital               Analog
+ * driver
+ * *--------*                                 * -> mux1 (virt bus2) -> mux -> |
+ * | I2CLPC | i2c physical                    * -> mux2 (virt bus3) -> mux -> |
+ * | bridge | bus 1                 *---------*                               |
+ * | logic  |---------------------> * mux reg *                               |
+ * | in CPLD|                       *---------*                               |
+ * *--------*   i2c-mux-mlxpcld          ^    * -> muxn (virt busn) -> mux -> |
+ *     |        driver                   |                                    |
+ *     |        *---------------*        |                              Devices
+ *     |        * CPLD (i2c bus)* select |
+ *     |        * registers for *--------*
+ *     |        * mux selection * deselect
+ *     |        *---------------*
+ *     |                 |
+ * <-------->     <----------->
+ * i2c cntrl      Board cntrl reg
+ * reg space      space (mux select,
+ *                IO, LED, WD, info)
+ *
+ */
+
+static const struct i2c_device_id mlxcpld_mux_id[] = {
+	{ "mlxcpld_mux_module", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, mlxcpld_mux_id);
+
+/* Write to mux register. Don't use i2c_transfer() and i2c_smbus_xfer()
+ * for this as they will try to lock adapter a second time.
+ */
+static int mlxcpld_mux_reg_write(struct i2c_adapter *adap,
+				 struct i2c_client *client, u8 val)
+{
+	struct mlxcpld_mux_plat_data *pdata = dev_get_platdata(&client->dev);
+
+	if (adap->algo->master_xfer) {
+		struct i2c_msg msg;
+		u8 msgbuf[] = {pdata->sel_reg_addr, val};
+
+		msg.addr = client->addr;
+		msg.flags = 0;
+		msg.len = 2;
+		msg.buf = msgbuf;
+		return __i2c_transfer(adap, &msg, 1);
+	} else if (adap->algo->smbus_xfer) {
+		union i2c_smbus_data data;
+
+		data.byte = val;
+		return adap->algo->smbus_xfer(adap, client->addr,
+					      client->flags, I2C_SMBUS_WRITE,
+					      pdata->sel_reg_addr,
+					      I2C_SMBUS_BYTE_DATA, &data);
+	} else
+		return -ENODEV;
+}
+
+static int mlxcpld_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
+{
+	struct mlxcpld_mux *data = i2c_mux_priv(muxc);
+	struct i2c_client *client = data->client;
+	u8 regval = chan + 1;
+	int err = 0;
+
+	/* Only select the channel if its different from the last channel */
+	if (data->last_chan != regval) {
+		err = mlxcpld_mux_reg_write(muxc->parent, client, regval);
+		if (err)
+			data->last_chan = 0;
+		else
+			data->last_chan = regval;
+	}
+
+	return err;
+}
+
+static int mlxcpld_mux_deselect(struct i2c_mux_core *muxc, u32 chan)
+{
+	struct mlxcpld_mux *data = i2c_mux_priv(muxc);
+	struct i2c_client *client = data->client;
+
+	/* Deselect active channel */
+	data->last_chan = 0;
+
+	return mlxcpld_mux_reg_write(muxc->parent, client, data->last_chan);
+}
+
+/* Probe/reomove functions */
+static int mlxcpld_mux_probe(struct i2c_client *client,
+			     const struct i2c_device_id *id)
+{
+	struct i2c_adapter *adap = to_i2c_adapter(client->dev.parent);
+	struct mlxcpld_mux_plat_data *pdata = dev_get_platdata(&client->dev);
+	struct i2c_mux_core *muxc;
+	int num, force;
+	struct mlxcpld_mux *data;
+	int err;
+
+	if (!pdata)
+		return -EINVAL;
+
+	if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
+		return -ENODEV;
+
+	muxc = i2c_mux_alloc(adap, &client->dev, CPLD_MUX_MAX_NCHANS,
+			     sizeof(*data), 0, mlxcpld_mux_select_chan,
+			     mlxcpld_mux_deselect);
+	if (!muxc)
+		return -ENOMEM;
+
+	data = i2c_mux_priv(muxc);
+	i2c_set_clientdata(client, muxc);
+	data->client = client;
+	data->last_chan = 0; /* force the first selection */
+
+	/* Create an adapter for each channel. */
+	for (num = 0; num < CPLD_MUX_MAX_NCHANS; num++) {
+		if (num >= pdata->num_adaps)
+			/* discard unconfigured channels */
+			break;
+
+		force = pdata->adap_ids[num];
+
+		err = i2c_mux_add_adapter(muxc, force, num, 0);
+		if (err)
+			goto virt_reg_failed;
+	}
+
+	return 0;
+
+virt_reg_failed:
+	i2c_mux_del_adapters(muxc);
+	return err;
+}
+
+static int mlxcpld_mux_remove(struct i2c_client *client)
+{
+	struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+
+	i2c_mux_del_adapters(muxc);
+	return 0;
+}
+
+static struct i2c_driver mlxcpld_mux_driver = {
+	.driver		= {
+		.name	= "mlxcpld-mux",
+	},
+	.probe		= mlxcpld_mux_probe,
+	.remove		= mlxcpld_mux_remove,
+	.id_table	= mlxcpld_mux_id,
+};
+
+module_i2c_driver(mlxcpld_mux_driver);
+
+MODULE_AUTHOR("Michael Shych ([e-mail])");
+MODULE_DESCRIPTION("Mellanox I2C-CPLD-MUX driver");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS("platform:i2c-mux-mlxcpld");

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

···
  * warranty of any kind, whether express or implied.
  */
 
+#include <linux/acpi.h>
 #include <linux/device.h>
 #include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
···
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, pca954x_id);
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id pca954x_acpi_ids[] = {
+	{ .id = "PCA9540", .driver_data = pca_9540 },
+	{ .id = "PCA9542", .driver_data = pca_9540 },
+	{ .id = "PCA9543", .driver_data = pca_9543 },
+	{ .id = "PCA9544", .driver_data = pca_9544 },
+	{ .id = "PCA9545", .driver_data = pca_9545 },
+	{ .id = "PCA9546", .driver_data = pca_9545 },
+	{ .id = "PCA9547", .driver_data = pca_9547 },
+	{ .id = "PCA9548", .driver_data = pca_9548 },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, pca954x_acpi_ids);
+#endif
 
 #ifdef CONFIG_OF
 static const struct of_device_id pca954x_of_match[] = {
···
 	match = of_match_device(of_match_ptr(pca954x_of_match), &client->dev);
 	if (match)
 		data->chip = of_device_get_match_data(&client->dev);
-	else
+	else if (id)
 		data->chip = &chips[id->driver_data];
+	else {
+		const struct acpi_device_id *acpi_id;
+
+		acpi_id = acpi_match_device(ACPI_PTR(pca954x_acpi_ids),
+						&client->dev);
+		if (!acpi_id)
+			return -ENODEV;
+		data->chip = &chips[acpi_id->driver_data];
+	}
 
 	data->last_chan = 0;		   /* force the first selection */
 
···
 		.name	= "pca954x",
 		.pm	= &pca954x_pm,
 		.of_match_table = of_match_ptr(pca954x_of_match),
+		.acpi_match_table = ACPI_PTR(pca954x_acpi_ids),
 	},
 	.probe		= pca954x_probe,
 	.remove		= pca954x_remove,

drivers/mfd/88pm860x-core.c

···
 	return 0;
 }
 
-static int pm860x_probe(struct i2c_client *client,
-				  const struct i2c_device_id *id)
+static int pm860x_probe(struct i2c_client *client)
 {
 	struct pm860x_platform_data *pdata = dev_get_platdata(&client->dev);
 	struct device_node *node = client->dev.of_node;
···
 		.pm     = &pm860x_pm_ops,
 		.of_match_table	= pm860x_dt_ids,
 	},
-	.probe		= pm860x_probe,
+	.probe_new	= pm860x_probe,
 	.remove		= pm860x_remove,
 	.id_table	= pm860x_id_table,
 };

include/linux/i2c-smbus.h

···
 					 struct i2c_smbus_alert_setup *setup);
 int i2c_handle_smbus_alert(struct i2c_client *ara);
 
-/**
- * smbus_host_notify - internal structure used by the Host Notify mechanism.
- * @adapter: the I2C adapter associated with this struct
- * @work: worker used to schedule the IRQ in the slave device
- * @lock: spinlock to check if a notification is already pending
- * @pending: flag set when a notification is pending (any new notification will
- *		be rejected if pending is true)
- * @payload: the actual payload of the Host Notify event
- * @addr: the address of the slave device which raised the notification
- *
- * This struct needs to be allocated by i2c_setup_smbus_host_notify() and does
- * not need to be freed. Internally, i2c_setup_smbus_host_notify() uses a
- * managed resource to clean this up when the adapter get released.
- */
-struct smbus_host_notify {
-	struct i2c_adapter	*adapter;
-	struct work_struct	work;
-	spinlock_t		lock;
-	bool			pending;
-	u16			payload;
-	u8			addr;
-};
-
-struct smbus_host_notify *i2c_setup_smbus_host_notify(struct i2c_adapter *adap);
-int i2c_handle_smbus_host_notify(struct smbus_host_notify *host_notify,
-				 unsigned short addr, unsigned int data);
-
 #endif /* _LINUX_I2C_SMBUS_H */

include/linux/i2c.h

···
 #include <linux/device.h>	/* for struct device */
 #include <linux/sched.h>	/* for completion */
 #include <linux/mutex.h>
+#include <linux/irqdomain.h>		/* for Host Notify IRQ */
 #include <linux/of.h>		/* for struct device_node */
 #include <linux/swab.h>		/* for swab16 */
 #include <uapi/linux/i2c.h>
···
  * struct i2c_driver - represent an I2C device driver
  * @class: What kind of i2c device we instantiate (for detect)
  * @attach_adapter: Callback for bus addition (deprecated)
- * @probe: Callback for device binding
+ * @probe: Callback for device binding - soon to be deprecated
+ * @probe_new: New callback for device binding
  * @remove: Callback for device unbinding
  * @shutdown: Callback for device shutdown
  * @alert: Alert callback, for example for the SMBus alert protocol
···
 	/* Standard driver model interfaces */
 	int (*probe)(struct i2c_client *, const struct i2c_device_id *);
 	int (*remove)(struct i2c_client *);
+
+	/* New driver model interface to aid the seamless removal of the
+	 * current probe()'s, more commonly unused than used second parameter.
+	 */
+	int (*probe_new)(struct i2c_client *);
 
 	/* driver model interfaces that don't relate to enumeration  */
 	void (*shutdown)(struct i2c_client *);
···
 
 extern struct i2c_client *i2c_verify_client(struct device *dev);
 extern struct i2c_adapter *i2c_verify_adapter(struct device *dev);
+extern const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
+					const struct i2c_client *client);
 
 static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
 {
···
 
 	struct i2c_bus_recovery_info *bus_recovery_info;
 	const struct i2c_adapter_quirks *quirks;
+
+	struct irq_domain *host_notify_domain;
 };
 #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
 
···
 	return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0);
 }
 
+int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr);
 /**
  * module_i2c_driver() - Helper macro for registering a modular I2C driver
  * @__i2c_driver: i2c_driver struct
···
 /* must call i2c_put_adapter() when done with returned i2c_adapter device */
 struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node);
 
+extern const struct of_device_id
+*i2c_of_match_device(const struct of_device_id *matches,
+		     struct i2c_client *client);
+
 #else
 
 static inline struct i2c_client *of_find_i2c_device_by_node(struct device_node *node)
···
 {
 	return NULL;
 }
+
+static inline const struct of_device_id
+*i2c_of_match_device(const struct of_device_id *matches,
+		     struct i2c_client *client)
+{
+	return NULL;
+}
+
 #endif /* CONFIG_OF */
 
 #if IS_ENABLED(CONFIG_ACPI)

include/linux/i2c/mlxcpld.h

···
+/*
+ * mlxcpld.h - Mellanox I2C multiplexer support in CPLD
+ *
+ * Copyright (c) 2016 Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2016 Michael Shych <[e-mail]>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _LINUX_I2C_MLXCPLD_H
+#define _LINUX_I2C_MLXCPLD_H
+
+/* Platform data for the CPLD I2C multiplexers */
+
+/* mlxcpld_mux_plat_data - per mux data, used with i2c_register_board_info
+ * @adap_ids - adapter array
+ * @num_adaps - number of adapters
+ * @sel_reg_addr - mux select register offset in CPLD space
+ */
+struct mlxcpld_mux_plat_data {
+	int *adap_ids;
+	int num_adaps;
+	int sel_reg_addr;
+};
+
+#endif /* _LINUX_I2C_MLXCPLD_H */