Merge branch 'i2c/for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:
 "I2C has not so much stuff this time. Mostly driver enablement for new
  SoCs, some driver bugfixes, and some cleanups"

* 'i2c/for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (35 commits)
  MAINTAINERS: add maintainer for Renesas RIIC driver
  i2c: sh_mobile: Remove dummy runtime PM callbacks
  i2c: uniphier-f: fix race condition when IRQ is cleared
  i2c: uniphier-f: fix occasional timeout error
  i2c: uniphier-f: make driver robust against concurrency
  i2c: i2c-qcom-geni: Simplify irq handler
  i2c: i2c-qcom-geni: Simplify tx/rx functions
  i2c: designware: Set IRQF_NO_SUSPEND flag for all BYT and CHT controllers
  i2c: mux: mlxcpld: simplify code to reach the adapter
  i2c: mux: ltc4306: simplify code to reach the adapter
  i2c: mux: pca954x: simplify code to reach the adapter
  i2c: core: remove level of indentation in i2c_transfer
  i2c: core: remove outdated DEBUG output
  i2c: zx2967: use core to detect 'no zero length' quirk
  i2c: tegra: use core to detect 'no zero length' quirk
  i2c: qup: use core to detect 'no zero length' quirk
  i2c: omap: use core to detect 'no zero length' quirk
  i2c: Convert to using %pOFn instead of device_node.name
  i2c: brcmstb: Allow enabling the driver on DSL SoCs
  eeprom: at24: fix unexpected timeout under high load
  ...

22 files changed, 413 insertions, 298 deletions

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 451d4ae50e66..56ccb1ea7da5 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -432,12 +432,13 @@ config I2C_BCM_KONA
 	  If you do not need KONA I2C interface, say N.
 
 config I2C_BRCMSTB
-	tristate "BRCM Settop I2C controller"
-	depends on ARCH_BRCMSTB || BMIPS_GENERIC || COMPILE_TEST
+	tristate "BRCM Settop/DSL I2C controller"
+	depends on ARCH_BRCMSTB || BMIPS_GENERIC || ARCH_BCM_63XX || \
+		   COMPILE_TEST
 	default y
 	help
 	  If you say yes to this option, support will be included for the
-	  I2C interface on the Broadcom Settop SoCs.
+	  I2C interface on the Broadcom Settop/DSL SoCs.
 
 	  If you do not need I2C interface, say N.
 
diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
index a4f956c6d567..8dc9161ced38 100644
--- a/drivers/i2c/busses/i2c-aspeed.c
+++ b/drivers/i2c/busses/i2c-aspeed.c
@@ -82,6 +82,11 @@
 #define ASPEED_I2CD_INTR_RX_DONE			BIT(2)
 #define ASPEED_I2CD_INTR_TX_NAK				BIT(1)
 #define ASPEED_I2CD_INTR_TX_ACK				BIT(0)
+#define ASPEED_I2CD_INTR_MASTER_ERRORS					       \
+		(ASPEED_I2CD_INTR_SDA_DL_TIMEOUT |			       \
+		 ASPEED_I2CD_INTR_SCL_TIMEOUT |				       \
+		 ASPEED_I2CD_INTR_ABNORMAL |				       \
+		 ASPEED_I2CD_INTR_ARBIT_LOSS)
 #define ASPEED_I2CD_INTR_ALL						       \
 		(ASPEED_I2CD_INTR_SDA_DL_TIMEOUT |			       \
 		 ASPEED_I2CD_INTR_BUS_RECOVER_DONE |			       \
@@ -137,7 +142,8 @@ struct aspeed_i2c_bus {
 	/* Synchronizes I/O mem access to base. */
 	spinlock_t			lock;
 	struct completion		cmd_complete;
-	u32				(*get_clk_reg_val)(u32 divisor);
+	u32				(*get_clk_reg_val)(struct device *dev,
+							   u32 divisor);
 	unsigned long			parent_clk_frequency;
 	u32				bus_frequency;
 	/* Transaction state. */
@@ -227,32 +233,26 @@ reset_out:
 }
 
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
-static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus)
+static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
 {
-	u32 command, irq_status, status_ack = 0;
+	u32 command, irq_handled = 0;
 	struct i2c_client *slave = bus->slave;
-	bool irq_handled = true;
 	u8 value;
 
-	if (!slave) {
-		irq_handled = false;
-		goto out;
-	}
+	if (!slave)
+		return 0;
 
 	command = readl(bus->base + ASPEED_I2C_CMD_REG);
-	irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG);
 
 	/* Slave was requested, restart state machine. */
 	if (irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) {
-		status_ack |= ASPEED_I2CD_INTR_SLAVE_MATCH;
+		irq_handled |= ASPEED_I2CD_INTR_SLAVE_MATCH;
 		bus->slave_state = ASPEED_I2C_SLAVE_START;
 	}
 
 	/* Slave is not currently active, irq was for someone else. */
-	if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) {
-		irq_handled = false;
-		goto out;
-	}
+	if (bus->slave_state == ASPEED_I2C_SLAVE_STOP)
+		return irq_handled;
 
 	dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n",
 		irq_status, command);
@@ -269,31 +269,31 @@ static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus)
 				bus->slave_state =
 						ASPEED_I2C_SLAVE_WRITE_REQUESTED;
 		}
-		status_ack |= ASPEED_I2CD_INTR_RX_DONE;
+		irq_handled |= ASPEED_I2CD_INTR_RX_DONE;
 	}
 
 	/* Slave was asked to stop. */
 	if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) {
-		status_ack |= ASPEED_I2CD_INTR_NORMAL_STOP;
+		irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP;
 		bus->slave_state = ASPEED_I2C_SLAVE_STOP;
 	}
 	if (irq_status & ASPEED_I2CD_INTR_TX_NAK) {
-		status_ack |= ASPEED_I2CD_INTR_TX_NAK;
+		irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
 		bus->slave_state = ASPEED_I2C_SLAVE_STOP;
 	}
+	if (irq_status & ASPEED_I2CD_INTR_TX_ACK)
+		irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
 
 	switch (bus->slave_state) {
 	case ASPEED_I2C_SLAVE_READ_REQUESTED:
 		if (irq_status & ASPEED_I2CD_INTR_TX_ACK)
 			dev_err(bus->dev, "Unexpected ACK on read request.\n");
 		bus->slave_state = ASPEED_I2C_SLAVE_READ_PROCESSED;
-
 		i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value);
 		writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG);
 		writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG);
 		break;
 	case ASPEED_I2C_SLAVE_READ_PROCESSED:
-		status_ack |= ASPEED_I2CD_INTR_TX_ACK;
 		if (!(irq_status & ASPEED_I2CD_INTR_TX_ACK))
 			dev_err(bus->dev,
 				"Expected ACK after processed read.\n");
@@ -317,13 +317,6 @@ static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus)
 		break;
 	}
 
-	if (status_ack != irq_status)
-		dev_err(bus->dev,
-			"irq handled != irq. expected %x, but was %x\n",
-			irq_status, status_ack);
-	writel(status_ack, bus->base + ASPEED_I2C_INTR_STS_REG);
-
-out:
 	return irq_handled;
 }
 #endif /* CONFIG_I2C_SLAVE */
@@ -380,21 +373,21 @@ static int aspeed_i2c_is_irq_error(u32 irq_status)
 	return 0;
 }
 
-static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus)
+static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
 {
-	u32 irq_status, status_ack = 0, command = 0;
+	u32 irq_handled = 0, command = 0;
 	struct i2c_msg *msg;
 	u8 recv_byte;
 	int ret;
 
-	irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG);
-	/* Ack all interrupt bits. */
-	writel(irq_status, bus->base + ASPEED_I2C_INTR_STS_REG);
-
 	if (irq_status & ASPEED_I2CD_INTR_BUS_RECOVER_DONE) {
 		bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
-		status_ack |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE;
+		irq_handled |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE;
 		goto out_complete;
+	} else {
+		/* Master is not currently active, irq was for someone else. */
+		if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE)
+			goto out_no_complete;
 	}
 
 	/*
@@ -403,19 +396,22 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus)
 	 * INACTIVE state.
 	 */
 	ret = aspeed_i2c_is_irq_error(irq_status);
-	if (ret < 0) {
+	if (ret) {
 		dev_dbg(bus->dev, "received error interrupt: 0x%08x\n",
 			irq_status);
 		bus->cmd_err = ret;
 		bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
+		irq_handled |= (irq_status & ASPEED_I2CD_INTR_MASTER_ERRORS);
 		goto out_complete;
 	}
 
 	/* We are in an invalid state; reset bus to a known state. */
 	if (!bus->msgs) {
-		dev_err(bus->dev, "bus in unknown state\n");
+		dev_err(bus->dev, "bus in unknown state. irq_status: 0x%x\n",
+			irq_status);
 		bus->cmd_err = -EIO;
-		if (bus->master_state != ASPEED_I2C_MASTER_STOP)
+		if (bus->master_state != ASPEED_I2C_MASTER_STOP &&
+		    bus->master_state != ASPEED_I2C_MASTER_INACTIVE)
 			aspeed_i2c_do_stop(bus);
 		goto out_no_complete;
 	}
@@ -428,13 +424,18 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus)
 	 */
 	if (bus->master_state == ASPEED_I2C_MASTER_START) {
 		if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) {
+			if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_NAK))) {
+				bus->cmd_err = -ENXIO;
+				bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
+				goto out_complete;
+			}
 			pr_devel("no slave present at %02x\n", msg->addr);
-			status_ack |= ASPEED_I2CD_INTR_TX_NAK;
+			irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
 			bus->cmd_err = -ENXIO;
 			aspeed_i2c_do_stop(bus);
 			goto out_no_complete;
 		}
-		status_ack |= ASPEED_I2CD_INTR_TX_ACK;
+		irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
 		if (msg->len == 0) { /* SMBUS_QUICK */
 			aspeed_i2c_do_stop(bus);
 			goto out_no_complete;
@@ -449,14 +450,14 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus)
 	case ASPEED_I2C_MASTER_TX:
 		if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_NAK)) {
 			dev_dbg(bus->dev, "slave NACKed TX\n");
-			status_ack |= ASPEED_I2CD_INTR_TX_NAK;
+			irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
 			goto error_and_stop;
 		} else if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) {
 			dev_err(bus->dev, "slave failed to ACK TX\n");
 			goto error_and_stop;
 		}
-		status_ack |= ASPEED_I2CD_INTR_TX_ACK;
-		/* fallthrough intended */
+		irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
+		/* fall through */
 	case ASPEED_I2C_MASTER_TX_FIRST:
 		if (bus->buf_index < msg->len) {
 			bus->master_state = ASPEED_I2C_MASTER_TX;
@@ -472,13 +473,13 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus)
 		/* RX may not have completed yet (only address cycle) */
 		if (!(irq_status & ASPEED_I2CD_INTR_RX_DONE))
 			goto out_no_complete;
-		/* fallthrough intended */
+		/* fall through */
 	case ASPEED_I2C_MASTER_RX:
 		if (unlikely(!(irq_status & ASPEED_I2CD_INTR_RX_DONE))) {
 			dev_err(bus->dev, "master failed to RX\n");
 			goto error_and_stop;
 		}
-		status_ack |= ASPEED_I2CD_INTR_RX_DONE;
+		irq_handled |= ASPEED_I2CD_INTR_RX_DONE;
 
 		recv_byte = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8;
 		msg->buf[bus->buf_index++] = recv_byte;
@@ -506,11 +507,13 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus)
 		goto out_no_complete;
 	case ASPEED_I2C_MASTER_STOP:
 		if (unlikely(!(irq_status & ASPEED_I2CD_INTR_NORMAL_STOP))) {
-			dev_err(bus->dev, "master failed to STOP\n");
+			dev_err(bus->dev,
+				"master failed to STOP. irq_status:0x%x\n",
+				irq_status);
 			bus->cmd_err = -EIO;
 			/* Do not STOP as we have already tried. */
 		} else {
-			status_ack |= ASPEED_I2CD_INTR_NORMAL_STOP;
+			irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP;
 		}
 
 		bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
@@ -540,33 +543,57 @@ out_complete:
 		bus->master_xfer_result = bus->msgs_index + 1;
 	complete(&bus->cmd_complete);
 out_no_complete:
-	if (irq_status != status_ack)
-		dev_err(bus->dev,
-			"irq handled != irq. expected 0x%08x, but was 0x%08x\n",
-			irq_status, status_ack);
-	return !!irq_status;
+	return irq_handled;
 }
 
 static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id)
 {
 	struct aspeed_i2c_bus *bus = dev_id;
-	bool ret;
+	u32 irq_received, irq_remaining, irq_handled;
 
 	spin_lock(&bus->lock);
+	irq_received = readl(bus->base + ASPEED_I2C_INTR_STS_REG);
+	/* Ack all interrupts except for Rx done */
+	writel(irq_received & ~ASPEED_I2CD_INTR_RX_DONE,
+	       bus->base + ASPEED_I2C_INTR_STS_REG);
+	irq_remaining = irq_received;
 
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
-	if (aspeed_i2c_slave_irq(bus)) {
-		dev_dbg(bus->dev, "irq handled by slave.\n");
-		ret = true;
-		goto out;
+	/*
+	 * In most cases, interrupt bits will be set one by one, although
+	 * multiple interrupt bits could be set at the same time. It's also
+	 * possible that master interrupt bits could be set along with slave
+	 * interrupt bits. Each case needs to be handled using corresponding
+	 * handlers depending on the current state.
+	 */
+	if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) {
+		irq_handled = aspeed_i2c_master_irq(bus, irq_remaining);
+		irq_remaining &= ~irq_handled;
+		if (irq_remaining)
+			irq_handled |= aspeed_i2c_slave_irq(bus, irq_remaining);
+	} else {
+		irq_handled = aspeed_i2c_slave_irq(bus, irq_remaining);
+		irq_remaining &= ~irq_handled;
+		if (irq_remaining)
+			irq_handled |= aspeed_i2c_master_irq(bus,
+							     irq_remaining);
 	}
+#else
+	irq_handled = aspeed_i2c_master_irq(bus, irq_remaining);
 #endif /* CONFIG_I2C_SLAVE */
 
-	ret = aspeed_i2c_master_irq(bus);
+	irq_remaining &= ~irq_handled;
+	if (irq_remaining)
+		dev_err(bus->dev,
+			"irq handled != irq. expected 0x%08x, but was 0x%08x\n",
+			irq_received, irq_handled);
 
-out:
+	/* Ack Rx done */
+	if (irq_received & ASPEED_I2CD_INTR_RX_DONE)
+		writel(ASPEED_I2CD_INTR_RX_DONE,
+		       bus->base + ASPEED_I2C_INTR_STS_REG);
 	spin_unlock(&bus->lock);
-	return ret ? IRQ_HANDLED : IRQ_NONE;
+	return irq_remaining ? IRQ_NONE : IRQ_HANDLED;
 }
 
 static int aspeed_i2c_master_xfer(struct i2c_adapter *adap,
@@ -684,16 +711,27 @@ static const struct i2c_algorithm aspeed_i2c_algo = {
 #endif /* CONFIG_I2C_SLAVE */
 };
 
-static u32 aspeed_i2c_get_clk_reg_val(u32 clk_high_low_max, u32 divisor)
+static u32 aspeed_i2c_get_clk_reg_val(struct device *dev,
+				      u32 clk_high_low_mask,
+				      u32 divisor)
 {
-	u32 base_clk, clk_high, clk_low, tmp;
+	u32 base_clk_divisor, clk_high_low_max, clk_high, clk_low, tmp;
+
+	/*
+	 * SCL_high and SCL_low represent a value 1 greater than what is stored
+	 * since a zero divider is meaningless. Thus, the max value each can
+	 * store is every bit set + 1. Since SCL_high and SCL_low are added
+	 * together (see below), the max value of both is the max value of one
+	 * them times two.
+	 */
+	clk_high_low_max = (clk_high_low_mask + 1) * 2;
 
 	/*
 	 * The actual clock frequency of SCL is:
 	 *	SCL_freq = APB_freq / (base_freq * (SCL_high + SCL_low))
 	 *		 = APB_freq / divisor
 	 * where base_freq is a programmable clock divider; its value is
-	 *	base_freq = 1 << base_clk
+	 *	base_freq = 1 << base_clk_divisor
 	 * SCL_high is the number of base_freq clock cycles that SCL stays high
 	 * and SCL_low is the number of base_freq clock cycles that SCL stays
 	 * low for a period of SCL.
@@ -703,47 +741,59 @@ static u32 aspeed_i2c_get_clk_reg_val(u32 clk_high_low_max, u32 divisor)
 	 *	SCL_low	 = clk_low + 1
 	 * Thus,
 	 *	SCL_freq = APB_freq /
-	 *		((1 << base_clk) * (clk_high + 1 + clk_low + 1))
+	 *		((1 << base_clk_divisor) * (clk_high + 1 + clk_low + 1))
 	 * The documentation recommends clk_high >= clk_high_max / 2 and
 	 * clk_low >= clk_low_max / 2 - 1 when possible; this last constraint
 	 * gives us the following solution:
 	 */
-	base_clk = divisor > clk_high_low_max ?
+	base_clk_divisor = divisor > clk_high_low_max ?
 			ilog2((divisor - 1) / clk_high_low_max) + 1 : 0;
-	tmp = (divisor + (1 << base_clk) - 1) >> base_clk;
-	clk_low = tmp / 2;
-	clk_high = tmp - clk_low;
 
-	if (clk_high)
-		clk_high--;
+	if (base_clk_divisor > ASPEED_I2CD_TIME_BASE_DIVISOR_MASK) {
+		base_clk_divisor = ASPEED_I2CD_TIME_BASE_DIVISOR_MASK;
+		clk_low = clk_high_low_mask;
+		clk_high = clk_high_low_mask;
+		dev_err(dev,
+			"clamping clock divider: divider requested, %u, is greater than largest possible divider, %u.\n",
+			divisor, (1 << base_clk_divisor) * clk_high_low_max);
+	} else {
+		tmp = (divisor + (1 << base_clk_divisor) - 1)
+				>> base_clk_divisor;
+		clk_low = tmp / 2;
+		clk_high = tmp - clk_low;
+
+		if (clk_high)
+			clk_high--;
 
-	if (clk_low)
-		clk_low--;
+		if (clk_low)
+			clk_low--;
+	}
 
 
 	return ((clk_high << ASPEED_I2CD_TIME_SCL_HIGH_SHIFT)
 		& ASPEED_I2CD_TIME_SCL_HIGH_MASK)
 			| ((clk_low << ASPEED_I2CD_TIME_SCL_LOW_SHIFT)
 			   & ASPEED_I2CD_TIME_SCL_LOW_MASK)
-			| (base_clk & ASPEED_I2CD_TIME_BASE_DIVISOR_MASK);
+			| (base_clk_divisor
+			   & ASPEED_I2CD_TIME_BASE_DIVISOR_MASK);
 }
 
-static u32 aspeed_i2c_24xx_get_clk_reg_val(u32 divisor)
+static u32 aspeed_i2c_24xx_get_clk_reg_val(struct device *dev, u32 divisor)
 {
 	/*
 	 * clk_high and clk_low are each 3 bits wide, so each can hold a max
 	 * value of 8 giving a clk_high_low_max of 16.
 	 */
-	return aspeed_i2c_get_clk_reg_val(16, divisor);
+	return aspeed_i2c_get_clk_reg_val(dev, GENMASK(2, 0), divisor);
 }
 
-static u32 aspeed_i2c_25xx_get_clk_reg_val(u32 divisor)
+static u32 aspeed_i2c_25xx_get_clk_reg_val(struct device *dev, u32 divisor)
 {
 	/*
 	 * clk_high and clk_low are each 4 bits wide, so each can hold a max
 	 * value of 16 giving a clk_high_low_max of 32.
 	 */
-	return aspeed_i2c_get_clk_reg_val(32, divisor);
+	return aspeed_i2c_get_clk_reg_val(dev, GENMASK(3, 0), divisor);
 }
 
 /* precondition: bus.lock has been acquired. */
@@ -756,7 +806,7 @@ static int aspeed_i2c_init_clk(struct aspeed_i2c_bus *bus)
 	clk_reg_val &= (ASPEED_I2CD_TIME_TBUF_MASK |
 			ASPEED_I2CD_TIME_THDSTA_MASK |
 			ASPEED_I2CD_TIME_TACST_MASK);
-	clk_reg_val |= bus->get_clk_reg_val(divisor);
+	clk_reg_val |= bus->get_clk_reg_val(bus->dev, divisor);
 	writel(clk_reg_val, bus->base + ASPEED_I2C_AC_TIMING_REG1);
 	writel(ASPEED_NO_TIMEOUT_CTRL, bus->base + ASPEED_I2C_AC_TIMING_REG2);
 
@@ -872,7 +922,8 @@ static int aspeed_i2c_probe_bus(struct platform_device *pdev)
 	if (!match)
 		bus->get_clk_reg_val = aspeed_i2c_24xx_get_clk_reg_val;
 	else
-		bus->get_clk_reg_val = (u32 (*)(u32))match->data;
+		bus->get_clk_reg_val = (u32 (*)(struct device *, u32))
+				match->data;
 
 	/* Initialize the I2C adapter */
 	spin_lock_init(&bus->lock);
diff --git a/drivers/i2c/busses/i2c-designware-baytrail.c b/drivers/i2c/busses/i2c-designware-baytrail.c
index a2a275cfc1f6..9ca1feaba98f 100644
--- a/drivers/i2c/busses/i2c-designware-baytrail.c
+++ b/drivers/i2c/busses/i2c-designware-baytrail.c
@@ -164,7 +164,7 @@ int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev)
 	dev_info(dev->dev, "I2C bus managed by PUNIT\n");
 	dev->acquire_lock = baytrail_i2c_acquire;
 	dev->release_lock = baytrail_i2c_release;
-	dev->pm_disabled = true;
+	dev->shared_with_punit = true;
 
 	pm_qos_add_request(&dev->pm_qos, PM_QOS_CPU_DMA_LATENCY,
 			   PM_QOS_DEFAULT_VALUE);
diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index 69ec4a791f23..36271cd75342 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -201,6 +201,8 @@ int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev)
 		dev_dbg(dev->dev, "SDA Hold Time TX:RX = %d:%d\n",
 			dev->sda_hold_time & ~(u32)DW_IC_SDA_HOLD_RX_MASK,
 			dev->sda_hold_time >> DW_IC_SDA_HOLD_RX_SHIFT);
+	} else if (dev->set_sda_hold_time) {
+		dev->set_sda_hold_time(dev);
 	} else if (dev->sda_hold_time) {
 		dev_warn(dev->dev,
 			"Hardware too old to adjust SDA hold time.\n");
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index e367b1af4ab2..9ec8394f4787 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -212,7 +212,7 @@
  * @pm_qos: pm_qos_request used while holding a hardware lock on the bus
  * @acquire_lock: function to acquire a hardware lock on the bus
  * @release_lock: function to release a hardware lock on the bus
- * @pm_disabled: true if power-management should be disabled for this i2c-bus
+ * @shared_with_punit: true if this bus is shared with the SoCs PUNIT
  * @disable: function to disable the controller
  * @disable_int: function to disable all interrupts
  * @init: function to initialize the I2C hardware
@@ -225,6 +225,7 @@
 struct dw_i2c_dev {
 	struct device		*dev;
 	void __iomem		*base;
+	void __iomem		*ext;
 	struct completion	cmd_complete;
 	struct clk		*clk;
 	struct reset_control	*rst;
@@ -265,10 +266,11 @@ struct dw_i2c_dev {
 	struct pm_qos_request	pm_qos;
 	int			(*acquire_lock)(struct dw_i2c_dev *dev);
 	void			(*release_lock)(struct dw_i2c_dev *dev);
-	bool			pm_disabled;
+	bool			shared_with_punit;
 	void			(*disable)(struct dw_i2c_dev *dev);
 	void			(*disable_int)(struct dw_i2c_dev *dev);
 	int			(*init)(struct dw_i2c_dev *dev);
+	int			(*set_sda_hold_time)(struct dw_i2c_dev *dev);
 	int			mode;
 	struct i2c_bus_recovery_info rinfo;
 };
@@ -276,8 +278,11 @@ struct dw_i2c_dev {
 #define ACCESS_SWAP		0x00000001
 #define ACCESS_16BIT		0x00000002
 #define ACCESS_INTR_MASK	0x00000004
+#define ACCESS_NO_IRQ_SUSPEND	0x00000008
 
 #define MODEL_CHERRYTRAIL	0x00000100
+#define MODEL_MSCC_OCELOT	0x00000200
+#define MODEL_MASK		0x00000f00
 
 u32 dw_readl(struct dw_i2c_dev *dev, int offset);
 void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset);
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index 18cc324f3ca9..8d1bc44d2530 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -709,7 +709,7 @@ int i2c_dw_probe(struct dw_i2c_dev *dev)
 	adap->dev.parent = dev->dev;
 	i2c_set_adapdata(adap, dev);
 
-	if (dev->pm_disabled) {
+	if (dev->flags & ACCESS_NO_IRQ_SUSPEND) {
 		irq_flags = IRQF_NO_SUSPEND;
 	} else {
 		irq_flags = IRQF_SHARED | IRQF_COND_SUSPEND;
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index b5750fd85125..997bbb3d925f 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -85,10 +85,6 @@ static int dw_i2c_acpi_configure(struct platform_device *pdev)
 	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
 	struct i2c_timings *t = &dev->timings;
 	u32 ss_ht = 0, fp_ht = 0, hs_ht = 0, fs_ht = 0;
-	acpi_handle handle = ACPI_HANDLE(&pdev->dev);
-	const struct acpi_device_id *id;
-	struct acpi_device *adev;
-	const char *uid;
 
 	dev->adapter.nr = -1;
 	dev->tx_fifo_depth = 32;
@@ -119,22 +115,6 @@ static int dw_i2c_acpi_configure(struct platform_device *pdev)
 		break;
 	}
 
-	id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
-	if (id && id->driver_data)
-		dev->flags |= (u32)id->driver_data;
-
-	if (acpi_bus_get_device(handle, &adev))
-		return -ENODEV;
-
-	/*
-	 * Cherrytrail I2C7 gets used for the PMIC which gets accessed
-	 * through ACPI opregions during late suspend / early resume
-	 * disable pm for it.
-	 */
-	uid = adev->pnp.unique_id;
-	if ((dev->flags & MODEL_CHERRYTRAIL) && !strcmp(uid, "7"))
-		dev->pm_disabled = true;
-
 	return 0;
 }
 
@@ -143,8 +123,8 @@ static const struct acpi_device_id dw_i2c_acpi_match[] = {
 	{ "INT33C3", 0 },
 	{ "INT3432", 0 },
 	{ "INT3433", 0 },
-	{ "80860F41", 0 },
-	{ "808622C1", MODEL_CHERRYTRAIL },
+	{ "80860F41", ACCESS_NO_IRQ_SUSPEND },
+	{ "808622C1", ACCESS_NO_IRQ_SUSPEND | MODEL_CHERRYTRAIL },
 	{ "AMD0010", ACCESS_INTR_MASK },
 	{ "AMDI0010", ACCESS_INTR_MASK },
 	{ "AMDI0510", 0 },
@@ -161,6 +141,51 @@ static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
 }
 #endif
 
+#ifdef CONFIG_OF
+#define MSCC_ICPU_CFG_TWI_DELAY		0x0
+#define MSCC_ICPU_CFG_TWI_DELAY_ENABLE	BIT(0)
+#define MSCC_ICPU_CFG_TWI_SPIKE_FILTER	0x4
+
+static int mscc_twi_set_sda_hold_time(struct dw_i2c_dev *dev)
+{
+	writel((dev->sda_hold_time << 1) | MSCC_ICPU_CFG_TWI_DELAY_ENABLE,
+	       dev->ext + MSCC_ICPU_CFG_TWI_DELAY);
+
+	return 0;
+}
+
+static int dw_i2c_of_configure(struct platform_device *pdev)
+{
+	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
+	struct resource *mem;
+
+	switch (dev->flags & MODEL_MASK) {
+	case MODEL_MSCC_OCELOT:
+		mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+		dev->ext = devm_ioremap_resource(&pdev->dev, mem);
+		if (!IS_ERR(dev->ext))
+			dev->set_sda_hold_time = mscc_twi_set_sda_hold_time;
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id dw_i2c_of_match[] = {
+	{ .compatible = "snps,designware-i2c", },
+	{ .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT },
+	{},
+};
+MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
+#else
+static inline int dw_i2c_of_configure(struct platform_device *pdev)
+{
+	return -ENODEV;
+}
+#endif
+
 static void i2c_dw_configure_master(struct dw_i2c_dev *dev)
 {
 	struct i2c_timings *t = &dev->timings;
@@ -221,7 +246,7 @@ static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
 {
 	pm_runtime_disable(dev->dev);
 
-	if (dev->pm_disabled)
+	if (dev->shared_with_punit)
 		pm_runtime_put_noidle(dev->dev);
 }
 
@@ -291,6 +316,11 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 	else
 		t->bus_freq_hz = 400000;
 
+	dev->flags |= (uintptr_t)device_get_match_data(&pdev->dev);
+
+	if (pdev->dev.of_node)
+		dw_i2c_of_configure(pdev);
+
 	if (has_acpi_companion(&pdev->dev))
 		dw_i2c_acpi_configure(pdev);
 
@@ -348,7 +378,7 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_set_active(&pdev->dev);
 
-	if (dev->pm_disabled)
+	if (dev->shared_with_punit)
 		pm_runtime_get_noresume(&pdev->dev);
 
 	pm_runtime_enable(&pdev->dev);
@@ -393,14 +423,6 @@ static int dw_i2c_plat_remove(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_OF
-static const struct of_device_id dw_i2c_of_match[] = {
-	{ .compatible = "snps,designware-i2c", },
-	{},
-};
-MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
-#endif
-
 #ifdef CONFIG_PM_SLEEP
 static int dw_i2c_plat_prepare(struct device *dev)
 {
@@ -434,7 +456,7 @@ static int dw_i2c_plat_suspend(struct device *dev)
 {
 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 
-	if (i_dev->pm_disabled)
+	if (i_dev->shared_with_punit)
 		return 0;
 
 	i_dev->disable(i_dev);
@@ -447,7 +469,7 @@ static int dw_i2c_plat_resume(struct device *dev)
 {
 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 
-	if (!i_dev->pm_disabled)
+	if (!i_dev->shared_with_punit)
 		i2c_dw_prepare_clk(i_dev, true);
 
 	i_dev->init(i_dev);
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index 1e57f58fcb00..a74ef76705e0 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -441,6 +441,8 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
 	u16 control_reg;
 	u16 restart_flag = 0;
 	u32 reg_4g_mode;
+	u8 *dma_rd_buf = NULL;
+	u8 *dma_wr_buf = NULL;
 	dma_addr_t rpaddr = 0;
 	dma_addr_t wpaddr = 0;
 	int ret;
@@ -500,10 +502,18 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
 	if (i2c->op == I2C_MASTER_RD) {
 		writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG);
 		writel(I2C_DMA_CON_RX, i2c->pdmabase + OFFSET_CON);
-		rpaddr = dma_map_single(i2c->dev, msgs->buf,
+
+		dma_rd_buf = i2c_get_dma_safe_msg_buf(msgs, 0);
+		if (!dma_rd_buf)
+			return -ENOMEM;
+
+		rpaddr = dma_map_single(i2c->dev, dma_rd_buf,
 					msgs->len, DMA_FROM_DEVICE);
-		if (dma_mapping_error(i2c->dev, rpaddr))
+		if (dma_mapping_error(i2c->dev, rpaddr)) {
+			i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, false);
+
 			return -ENOMEM;
+		}
 
 		if (i2c->dev_comp->support_33bits) {
 			reg_4g_mode = mtk_i2c_set_4g_mode(rpaddr);
@@ -515,10 +525,18 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
 	} else if (i2c->op == I2C_MASTER_WR) {
 		writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG);
 		writel(I2C_DMA_CON_TX, i2c->pdmabase + OFFSET_CON);
-		wpaddr = dma_map_single(i2c->dev, msgs->buf,
+
+		dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 0);
+		if (!dma_wr_buf)
+			return -ENOMEM;
+
+		wpaddr = dma_map_single(i2c->dev, dma_wr_buf,
 					msgs->len, DMA_TO_DEVICE);
-		if (dma_mapping_error(i2c->dev, wpaddr))
+		if (dma_mapping_error(i2c->dev, wpaddr)) {
+			i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
+
 			return -ENOMEM;
+		}
 
 		if (i2c->dev_comp->support_33bits) {
 			reg_4g_mode = mtk_i2c_set_4g_mode(wpaddr);
@@ -530,16 +548,39 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
 	} else {
 		writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_INT_FLAG);
 		writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_CON);
-		wpaddr = dma_map_single(i2c->dev, msgs->buf,
+
+		dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 0);
+		if (!dma_wr_buf)
+			return -ENOMEM;
+
+		wpaddr = dma_map_single(i2c->dev, dma_wr_buf,
 					msgs->len, DMA_TO_DEVICE);
-		if (dma_mapping_error(i2c->dev, wpaddr))
+		if (dma_mapping_error(i2c->dev, wpaddr)) {
+			i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
+
 			return -ENOMEM;
-		rpaddr = dma_map_single(i2c->dev, (msgs + 1)->buf,
+		}
+
+		dma_rd_buf = i2c_get_dma_safe_msg_buf((msgs + 1), 0);
+		if (!dma_rd_buf) {
+			dma_unmap_single(i2c->dev, wpaddr,
+					 msgs->len, DMA_TO_DEVICE);
+
+			i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
+
+			return -ENOMEM;
+		}
+
+		rpaddr = dma_map_single(i2c->dev, dma_rd_buf,
 					(msgs + 1)->len,
 					DMA_FROM_DEVICE);
 		if (dma_mapping_error(i2c->dev, rpaddr)) {
 			dma_unmap_single(i2c->dev, wpaddr,
 					 msgs->len, DMA_TO_DEVICE);
+
+			i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
+			i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), false);
+
 			return -ENOMEM;
 		}
 
@@ -578,14 +619,21 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
 	if (i2c->op == I2C_MASTER_WR) {
 		dma_unmap_single(i2c->dev, wpaddr,
 				 msgs->len, DMA_TO_DEVICE);
+
+		i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true);
 	} else if (i2c->op == I2C_MASTER_RD) {
 		dma_unmap_single(i2c->dev, rpaddr,
 				 msgs->len, DMA_FROM_DEVICE);
+
+		i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, true);
 	} else {
 		dma_unmap_single(i2c->dev, wpaddr, msgs->len,
 				 DMA_TO_DEVICE);
 		dma_unmap_single(i2c->dev, rpaddr, (msgs + 1)->len,
 				 DMA_FROM_DEVICE);
+
+		i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true);