4 files changed, 54 insertions, 10 deletions

diff --git a/drivers/i2c/i2c-uclass.c b/drivers/i2c/i2c-uclass.c
index 49e23a0a4b..e47abf1833 100644
--- a/drivers/i2c/i2c-uclass.c
+++ b/drivers/i2c/i2c-uclass.c
@@ -593,6 +593,29 @@ int i2c_chip_ofdata_to_platdata(struct udevice *dev, struct dm_i2c_chip *chip)
 }
 #endif
 
+static int i2c_pre_probe(struct udevice *dev)
+{
+#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
+	struct dm_i2c_bus *i2c = dev_get_uclass_priv(dev);
+	unsigned int max = 0;
+	ofnode node;
+	int ret;
+
+	i2c->max_transaction_bytes = 0;
+	dev_for_each_subnode(node, dev) {
+		ret = ofnode_read_u32(node,
+				      "u-boot,i2c-transaction-bytes",
+				      &max);
+		if (!ret && max > i2c->max_transaction_bytes)
+			i2c->max_transaction_bytes = max;
+	}
+
+	debug("%s: I2C bus: %s max transaction bytes: %d\n", __func__,
+	      dev->name, i2c->max_transaction_bytes);
+#endif
+	return 0;
+}
+
 static int i2c_post_probe(struct udevice *dev)
 {
 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
@@ -674,6 +697,7 @@ UCLASS_DRIVER(i2c) = {
 	.post_bind	= i2c_post_bind,
 	.init		= i2c_uclass_init,
 	.priv_auto_alloc_size = sizeof(struct i2c_priv),
+	.pre_probe      = i2c_pre_probe,
 	.post_probe	= i2c_post_probe,
 	.per_device_auto_alloc_size = sizeof(struct dm_i2c_bus),
 	.per_child_platdata_auto_alloc_size = sizeof(struct dm_i2c_chip),
diff --git a/drivers/i2c/muxes/Kconfig b/drivers/i2c/muxes/Kconfig
index b0da67ce2c..68f15261be 100644
--- a/drivers/i2c/muxes/Kconfig
+++ b/drivers/i2c/muxes/Kconfig
@@ -29,11 +29,12 @@ config I2C_MUX_PCA954x
 	tristate "TI PCA954x I2C Mux/switches"
 	depends on I2C_MUX
 	help
-	  If you say yes here you get support for the TI PCA954x
-	  I2C mux/switch devices. It is x width I2C multiplexer which enables to
-	  partitioning I2C bus and connect multiple devices with the same address
-	  to the same I2C controller where driver handles proper routing to
-	  target i2c device. PCA9544 and PCA9548 are supported.
+	  If you say yes here you get support for the TI PCA954x I2C mux/switch
+	  devices. It is x width I2C multiplexer which enables to partitioning
+	  I2C bus and connect multiple devices with the same address to the same
+	  I2C controller where driver handles proper routing to target i2c
+	  device. Supported chips are PCA9543, PCA9544, PCA9547, PCA9548 and
+	  PCA9646.
 
 config I2C_MUX_GPIO
         tristate "GPIO-based I2C multiplexer"
diff --git a/drivers/i2c/muxes/pca954x.c b/drivers/i2c/muxes/pca954x.c
index bd4e9abe5f..a630ce991d 100644
--- a/drivers/i2c/muxes/pca954x.c
+++ b/drivers/i2c/muxes/pca954x.c
@@ -15,6 +15,7 @@
 DECLARE_GLOBAL_DATA_PTR;
 
 enum pca_type {
+	PCA9543,
 	PCA9544,
 	PCA9547,
 	PCA9548,
@@ -22,7 +23,7 @@ enum pca_type {
 };
 
 struct chip_desc {
-	u8 enable;
+	u8 enable; /* Enable mask in ctl register (used for muxes only) */
 	enum muxtype {
 		pca954x_ismux = 0,
 		pca954x_isswi,
@@ -37,6 +38,10 @@ struct pca954x_priv {
 };
 
 static const struct chip_desc chips[] = {
+	[PCA9543] = {
+		.muxtype = pca954x_isswi,
+		.width = 2,
+	},
 	[PCA9544] = {
 		.enable = 0x4,
 		.muxtype = pca954x_ismux,
@@ -48,12 +53,10 @@ static const struct chip_desc chips[] = {
 		.width = 8,
 	},
 	[PCA9548] = {
-		.enable = 0x8,
 		.muxtype = pca954x_isswi,
 		.width = 8,
 	},
 	[PCA9646] = {
-		.enable = 0x0,
 		.muxtype = pca954x_isswi,
 		.width = 4,
 	},
@@ -89,6 +92,7 @@ static const struct i2c_mux_ops pca954x_ops = {
 };
 
 static const struct udevice_id pca954x_ids[] = {
+	{ .compatible = "nxp,pca9543", .data = PCA9543 },
 	{ .compatible = "nxp,pca9544", .data = PCA9544 },
 	{ .compatible = "nxp,pca9547", .data = PCA9547 },
 	{ .compatible = "nxp,pca9548", .data = PCA9548 },
diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c
index 9999d9fe5e..5420afbc8e 100644
--- a/drivers/i2c/mxc_i2c.c
+++ b/drivers/i2c/mxc_i2c.c
@@ -354,9 +354,10 @@ int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
 int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
 {
 	struct udevice *bus = i2c_bus->bus;
+	struct dm_i2c_bus *i2c = dev_get_uclass_priv(bus);
 	struct gpio_desc *scl_gpio = &i2c_bus->scl_gpio;
 	struct gpio_desc *sda_gpio = &i2c_bus->sda_gpio;
-	int sda, scl;
+	int sda, scl, idle_sclks;
 	int i, ret = 0;
 	ulong elapsed, start_time;
 
@@ -380,8 +381,22 @@ int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
 	if ((sda & scl) == 1)
 		goto exit;		/* Bus is idle already */
 
+	/*
+	 * In most cases it is just enough to generate 8 + 1 SCLK
+	 * clocks to recover I2C slave device from 'stuck' state
+	 * (when for example SW reset was performed, in the middle of
+	 * I2C transmission).
+	 *
+	 * However, there are devices which send data in packets of
+	 * N bytes (N > 1). In such case we do need N * 8 + 1 SCLK
+	 * clocks.
+	 */
+	idle_sclks = 8 + 1;
+
+	if (i2c->max_transaction_bytes > 0)
+		idle_sclks = i2c->max_transaction_bytes * 8 + 1;
 	/* Send high and low on the SCL line */
-	for (i = 0; i < 9; i++) {
+	for (i = 0; i < idle_sclks; i++) {
 		dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_OUT);
 		dm_gpio_set_value(scl_gpio, 0);
 		udelay(50);