i2c: lpc2k: add driver

manabian · Wolfram Sang · commit 3f9c37a0c9a5 · 2015-08-24T14:05:18.000+02:00
Add support for the I2C controller found on several NXP devices
including LPC2xxx, LPC178x/7x and LPC18xx/43xx. The controller
is implemented as a state machine and the driver act upon the
state changes when the bus is accessed.

The I2C controller supports master/slave operation, bus
arbitration, programmable clock rate, and speeds up to 1 Mbit/s.

Signed-off-by: Joachim Eastwood &lt;manabian@gmail.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
diff --git a/Documentation/devicetree/bindings/i2c/i2c-lpc2k.txt b/Documentation/devicetree/bindings/i2c/i2c-lpc2k.txt
@@ -0,0 +1,33 @@
+NXP I2C controller for LPC2xxx/178x/18xx/43xx
+
+Required properties:
+ - compatible: must be "nxp,lpc1788-i2c"
+ - reg: physical address and length of the device registers
+ - interrupts: a single interrupt specifier
+ - clocks: clock for the device
+ - #address-cells: should be <1>
+ - #size-cells: should be <0>
+
+Optional properties:
+- clock-frequency: the desired I2C bus clock frequency in Hz; in
+  absence of this property the default value is used (100 kHz).
+
+Example:
+i2c0: i2c@400a1000 {
+	compatible = "nxp,lpc1788-i2c";
+	reg = <0x400a1000 0x1000>;
+	interrupts = <18>;
+	clocks = <&ccu1 CLK_APB1_I2C0>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+};
+
+&i2c0 {
+	clock-frequency = <400000>;
+
+	lm75@48 {
+		compatible = "nxp,lm75";
+		reg = <0x48>;
+	};
+};
+
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
@@ -619,6 +619,16 @@ config I2C_KEMPLD
 	  This driver can also be built as a module. If so, the module
 	  will be called i2c-kempld.
 
+config I2C_LPC2K
+	tristate "I2C bus support for NXP LPC2K/LPC178x/18xx/43xx"
+	depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
+	help
+	  This driver supports the I2C interface found several NXP
+	  devices including LPC2xxx, LPC178x/7x and LPC18xx/43xx.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-lpc2k.
+
 config I2C_MESON
 	tristate "Amlogic Meson I2C controller"
 	depends on ARCH_MESON
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
@@ -59,6 +59,7 @@ obj-$(CONFIG_I2C_IMX)		+= i2c-imx.o
 obj-$(CONFIG_I2C_IOP3XX)	+= i2c-iop3xx.o
 obj-$(CONFIG_I2C_JZ4780)	+= i2c-jz4780.o
 obj-$(CONFIG_I2C_KEMPLD)	+= i2c-kempld.o
+obj-$(CONFIG_I2C_LPC2K)		+= i2c-lpc2k.o
 obj-$(CONFIG_I2C_MESON)		+= i2c-meson.o
 obj-$(CONFIG_I2C_MPC)		+= i2c-mpc.o
 obj-$(CONFIG_I2C_MT65XX)	+= i2c-mt65xx.o
diff --git a/drivers/i2c/busses/i2c-lpc2k.c b/drivers/i2c/busses/i2c-lpc2k.c
