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
  ...

32 files changed, 2068 insertions, 382 deletions

diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index 11edabf425ae..efc3354d60ae 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -7,6 +7,7 @@ menu "I2C support"
 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,
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index d252276feadf..0cdc8443deab 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -426,7 +426,7 @@ config I2C_BLACKFIN_TWI_CLK_KHZ
 
 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.
@@ -597,6 +597,16 @@ config I2C_IMX
 	  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
@@ -763,7 +773,7 @@ config I2C_PUV3
 
 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
@@ -1150,6 +1160,17 @@ config I2C_ELEKTOR
 	  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"
 	depends on ISA
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 29764cc20a44..1c1bac87a9db 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -56,6 +56,7 @@ obj-$(CONFIG_I2C_HIX5HD2)	+= i2c-hix5hd2.o
 obj-$(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
@@ -116,6 +117,7 @@ obj-$(CONFIG_I2C_BCM_KONA)	+= i2c-bcm-kona.o
 obj-$(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
diff --git a/drivers/i2c/busses/i2c-axxia.c b/drivers/i2c/busses/i2c-axxia.c
index 4351a9343058..13f07482ec68 100644
--- a/drivers/i2c/busses/i2c-axxia.c
+++ b/drivers/i2c/busses/i2c-axxia.c
@@ -489,7 +489,7 @@ static const struct i2c_algorithm axxia_i2c_algo = {
 	.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,
 };
diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c
index 326b3db02c48..318df559adc5 100644
--- a/drivers/i2c/busses/i2c-bcm-iproc.c
+++ b/drivers/i2c/busses/i2c-bcm-iproc.c
@@ -395,7 +395,7 @@ static const struct i2c_algorithm bcm_iproc_algo = {
 	.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,
 };
diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c
index d4f3239b5686..c3436f627028 100644
--- a/drivers/i2c/busses/i2c-bcm2835.c
+++ b/drivers/i2c/busses/i2c-bcm2835.c
@@ -50,20 +50,19 @@
 #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;
@@ -80,6 +79,30 @@ 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)
 {
 	u32 val;
@@ -110,106 +133,159 @@ static void bcm2835_drain_rxfifo(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);
-		return IRQ_HANDLED;
+		goto complete;
 	}
 
-	if (val & BCM2835_I2C_S_TXD) {
+	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_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;
+
+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);
+
+	return IRQ_HANDLED;
 }
 
-static int bcm2835_i2c_xfer_msg(struct bcm2835_i2c_dev *i2c_dev,
-				struct i2c_msg *msg)
+static int bcm2835_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
+			    int num)
 {
-	u32 c;
+	struct bcm2835_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
 	unsigned long time_left;
+	int i, ret;
 
-	i2c_dev->msg_buf = msg->buf;
-	i2c_dev->msg_buf_remaining = msg->len;
-	reinit_completion(&i2c_dev->completion);
+	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;
+		}
 
-	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, BCM2835_I2C_C_CLEAR);
+	ret = bcm2835_i2c_set_divider(i2c_dev);
+	if (ret)
+		return ret;
 
-	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;
+	i2c_dev->curr_msg = msgs;
+	i2c_dev->num_msgs = num;
+	reinit_completion(&i2c_dev->completion);
 
-	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);
+	bcm2835_i2c_start_transfer(i2c_dev);
 
 	time_left = wait_for_completion_timeout(&i2c_dev->completion,
-						BCM2835_I2C_TIMEOUT);
-	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, BCM2835_I2C_C_CLEAR);
+						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;
 	}
 
-	if (likely(!i2c_dev->msg_err))
-		return 0;
+	if (!i2c_dev->msg_err)
+		return num;
 
-	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);
+	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;
-	else
-		return -EIO;
-}
-
-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;
-
-	for (i = 0; i < num; i++) {
-		ret = bcm2835_i2c_xfer_msg(i2c_dev, &msgs[i]);
-		if (ret)
-			break;
-	}
 
-	return ret ?: i;
+	return -EIO;
 }
 
 static u32 bcm2835_i2c_func(struct i2c_adapter *adap)
@@ -235,7 +311,6 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
 {
 	struct bcm2835_i2c_dev *i2c_dev;
 	struct resource *mem, *irq;
-	u32 bus_clk_rate, divider;
 	int ret;
 	struct i2c_adapter *adap;
 
@@ -259,27 +334,12 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
 	}
 
 	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;
-	}
-
-	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;
+		i2c_dev->bus_clk_rate = 100000;
 	}
-	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_DIV, divider);
 
 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (!irq) {
diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index b403fa5ecf49..6d81c56184d3 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -536,6 +536,8 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
 	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
@@ -581,8 +583,15 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
 			 * 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) {
@@ -607,7 +616,12 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
 		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;
@@ -628,6 +642,24 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
 	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
 i2c_dw_read(struct dw_i2c_dev *dev)
 {
@@ -652,7 +684,15 @@ i2c_dw_read(struct dw_i2c_dev *dev)
 		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--;
 		}
 
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 0d44d2ae7d4c..26250b425e2f 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -22,6 +22,14 @@
  *
  */
 
+#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
diff --git a/drivers/i2c/busses/i2c-designware-pcidrv.c b/drivers/i2c/busses/i2c-designware-pcidrv.c
index 96f8230cd2d3..d6423cfac588 100644
--- a/drivers/i2c/busses/i2c-designware-pcidrv.c
+++ b/drivers/i2c/busses/i2c-designware-pcidrv.c
@@ -71,12 +71,6 @@ struct dw_pci_controller {
 				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,
@@ -147,6 +141,7 @@ static struct dw_pci_controller dw_pci_controllers[] = {
 		.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,
 	},
@@ -155,6 +150,7 @@ static struct dw_pci_controller dw_pci_controllers[] = {
 		.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,
 	},
@@ -249,7 +245,7 @@ static int i2c_dw_pci_probe(struct pci_dev *pdev,
 	}
 
 	dev->functionality = controller->functionality |
-				DW_DEFAULT_FUNCTIONALITY;
+				DW_IC_DEFAULT_FUNCTIONALITY;
 
 	dev->master_cfg = controller->bus_cfg;
 	if (controller->scl_sda_cfg) {
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 0b42a12171f3..08153ea4d848 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -176,9 +176,6 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 	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 {
@@ -193,8 +190,16 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 	}
 
 	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);
@@ -214,13 +219,7 @@ static int dw_i2c_plat_probe(struct platform_device *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;
diff --git a/drivers/i2c/busses/i2c-dln2.c b/drivers/i2c/busses/i2c-dln2.c
index 8acda2aa1558..69075a32073e 100644
--- a/drivers/i2c/busses/i2c-dln2.c
+++ b/drivers/i2c/busses/i2c-dln2.c
@@ -182,7 +182,7 @@ static const struct i2c_algorithm dln2_i2c_usb_algorithm = {
 	.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,
 };
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index eb3627f35d12..e242db43774b 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -118,7 +118,6 @@
 #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
@@ -137,27 +136,27 @@
 #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
@@ -172,27 +171,27 @@
 #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)
@@ -243,6 +242,7 @@ struct i801_priv {
 	struct i2c_adapter adapter;
 	unsigned long smba;
 	unsigned char original_hstcfg;
+	unsigned char original_slvcmd;
 	struct pci_dev *pci_dev;
 	unsigned int features;
 
@@ -269,20 +269,17 @@ struct i801_priv {
 	 */
 	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",
@@ -582,12 +579,15 @@ static void i801_isr_byte_done(struct i801_priv *priv)
 stat