Merge branch 'i2c-mux/for-next' of https://github.com/peda-r/i2c-mux …

…into i2c/for-4.12

Pull in changes from the i2c-mux subsubsystem:

"Here are a new LTC4306/5 driver, a fix needed by the RT kernel and some
error message cleanup."

Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt

@@ -0,0 +1,61 @@
+* Linear Technology / Analog Devices I2C bus switch
+
+Required Properties:
+
+  - compatible: Must contain one of the following.
+    "lltc,ltc4305", "lltc,ltc4306"
+  - reg: The I2C address of the device.
+
+  The following required properties are defined externally:
+
+  - Standard I2C mux properties. See i2c-mux.txt in this directory.
+  - I2C child bus nodes. See i2c-mux.txt in this directory.
+
+Optional Properties:
+
+  - enable-gpios: Reference to the GPIO connected to the enable input.
+  - i2c-mux-idle-disconnect: Boolean; if defined, forces mux to disconnect all
+    children in idle state. This is necessary for example, if there are several
+    multiplexers on the bus and the devices behind them use same I2C addresses.
+  - gpio-controller: Marks the device node as a GPIO Controller.
+  - #gpio-cells: Should be two.  The first cell is the pin number and
+	the second cell is used to specify flags.
+	See ../gpio/gpio.txt for more information.
+  - ltc,downstream-accelerators-enable: Enables the rise time accelerators
+	on the downstream port.
+  - ltc,upstream-accelerators-enable: Enables the rise time accelerators
+	on the upstream port.
+
+Example:
+
+	ltc4306: i2c-mux@4a {
+		compatible = "lltc,ltc4306";
+		#address-cells = <1>;
+		#size-cells = <0>;
+		reg = <0x4a>;
+
+		gpio-controller;
+		#gpio-cells = <2>;
+
+		i2c@0 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <0>;
+
+			eeprom@50 {
+				compatible = "at,24c02";
+				reg = <0x50>;
+			};
+		};
+
+		i2c@1 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <1>;
+
+			eeprom@50 {
+				compatible = "at,24c02";
+				reg = <0x50>;
+			};
+		};
+	};

MAINTAINERS

@@ -7698,6 +7698,14 @@ S:	Maintained
 F:	Documentation/hwmon/ltc4261
 F:	drivers/hwmon/ltc4261.c
 
+LTC4306 I2C MULTIPLEXER DRIVER
+M:	Michael Hennerich <michael.hennerich@analog.com>
+W:	http://ez.analog.com/community/linux-device-drivers
+L:	linux-i2c@vger.kernel.org
+S:	Supported
+F:	drivers/i2c/muxes/i2c-mux-ltc4306.c
+F:	Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
+
 LTP (Linux Test Project)
 M:	Mike Frysinger <vapier@gentoo.org>
 M:	Cyril Hrubis <chrubis@suse.cz>

drivers/i2c/i2c-mux.c

@@ -395,13 +395,16 @@ int i2c_mux_add_adapter(struct i2c_mux_core *muxc,
 	if (force_nr) {
 		priv->adap.nr = force_nr;
 		ret = i2c_add_numbered_adapter(&priv->adap);
+		dev_err(&parent->dev,
+			"failed to add mux-adapter %u as bus %u (error=%d)\n",
+			chan_id, force_nr, ret);
 	} else {
 		ret = i2c_add_adapter(&priv->adap);
+		dev_err(&parent->dev,
+			"failed to add mux-adapter %u (error=%d)\n",
+			chan_id, ret);
 	}
 	if (ret < 0) {
-		dev_err(&parent->dev,
-			"failed to add mux-adapter (error=%d)\n",
-			ret);
 		kfree(priv);
 		return ret;
 	}

drivers/i2c/muxes/Kconfig

@@ -30,6 +30,17 @@ config I2C_MUX_GPIO
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-mux-gpio.
 
+config I2C_MUX_LTC4306
+	tristate "LTC LTC4306/5 I2C multiplexer"
+	select GPIOLIB
+	select REGMAP_I2C
+	help
+	  If you say yes here you get support for the Analog Devices
+	  LTC4306 or LTC4305 I2C mux/switch devices.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-mux-ltc4306.
+
 config I2C_MUX_PCA9541
 	tristate "NXP PCA9541 I2C Master Selector"
 	help

drivers/i2c/muxes/Makefile

@@ -6,6 +6,7 @@ obj-$(CONFIG_I2C_ARB_GPIO_CHALLENGE)	+= i2c-arb-gpio-challenge.o
 obj-$(CONFIG_I2C_DEMUX_PINCTRL)		+= i2c-demux-pinctrl.o
 
 obj-$(CONFIG_I2C_MUX_GPIO)	+= i2c-mux-gpio.o
+obj-$(CONFIG_I2C_MUX_LTC4306)	+= i2c-mux-ltc4306.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

drivers/i2c/muxes/i2c-arb-gpio-challenge.c

@@ -202,10 +202,8 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
 
 	/* Actually add the mux adapter */
 	ret = i2c_mux_add_adapter(muxc, 0, 0, 0);
-	if (ret) {
-		dev_err(dev, "Failed to add adapter\n");
+	if (ret)
 		i2c_put_adapter(muxc->parent);
-	}
 
 	return ret;
 }

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

@@ -245,10 +245,8 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
 		unsigned int class = mux->data.classes ? mux->data.classes[i] : 0;
 
 		ret = i2c_mux_add_adapter(muxc, nr, mux->data.values[i], class);
-		if (ret) {
-			dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
+		if (ret)
 			goto add_adapter_failed;
-		}
 	}
 
 	dev_info(&pdev->dev, "%d port mux on %s adapter\n",