[PATCH v2 3/3] gpio/mxc: add device tree probe support

[Shawn Guo]

The patch adds device tree probe support for gpio-mxc driver.

Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
Cc: Grant Likely <grant.likely at secretlab.ca>
---
 .../devicetree/bindings/gpio/fsl-imx-gpio.txt      |   22 ++++++++++++++++++++
 drivers/gpio/gpio-mxc.c                            |   18 +++++++++++++++-
 2 files changed, 39 insertions(+), 1 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/gpio/fsl-imx-gpio.txt

diff --git a/Documentation/devicetree/bindings/gpio/fsl-imx-gpio.txt b/Documentation/devicetree/bindings/gpio/fsl-imx-gpio.txt
new file mode 100644
index 0000000..4363ae4
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/fsl-imx-gpio.txt
@@ -0,0 +1,22 @@
+* Freescale i.MX/MXC GPIO controller
+
+Required properties:
+- compatible : Should be "fsl,<soc>-gpio"
+- reg : Address and length of the register set for the device
+- interrupts : Should be the port interrupt shared by all 32 pins, if
+  one number.  If two numbers, the first one is the interrupt shared
+  by low 16 pins and the second one is for high 16 pins.
+- 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 optional parameters (currently
+  unused).
+
+Example:
+
+gpio0: gpio at 73f84000 {
+	compatible = "fsl,imx51-gpio", "fsl,imx31-gpio";
+	reg = <0x73f84000 0x4000>;
+	interrupts = <50 51>;
+	gpio-controller;
+	#gpio-cells = <2>;
+};
diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c
index 4875690..059d44a 100644
--- a/drivers/gpio/gpio-mxc.c
+++ b/drivers/gpio/gpio-mxc.c
@@ -27,6 +27,8 @@
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/basic_mmio_gpio.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 #include <asm-generic/bug.h>
 
 enum mxc_gpio_hwtype {
@@ -126,6 +128,13 @@ static struct platform_device_id mxc_gpio_devtype[] = {
 	}
 };
 
+static const struct of_device_id mxc_gpio_dt_ids[] = {
+	{ .compatible = "fsl,imx1-gpio", .data = &mxc_gpio_devtype[IMX1_GPIO], },
+	{ .compatible = "fsl,imx21-gpio", .data = &mxc_gpio_devtype[IMX2_GPIO], },
+	{ .compatible = "fsl,imx31-gpio", .data = &mxc_gpio_devtype[IMX_GPIO], },
+	{ /* sentinel */ }
+};
+
 /*
  * MX2 has one interrupt *for all* gpio ports. The list is used
  * to save the references to all ports, so that mx2_gpio_irq_handler
@@ -308,7 +317,13 @@ static void __init mxc_gpio_init_gc(struct mxc_gpio_port *port)
 
 static void __devinit mxc_gpio_get_hw(struct platform_device *pdev)
 {
-	enum mxc_gpio_hwtype hwtype = pdev->id_entry->driver_data;
+	const struct of_device_id *of_id =
+			of_match_device(mxc_gpio_dt_ids, &pdev->dev);
+	enum mxc_gpio_hwtype hwtype;
+
+	if (of_id)
+		pdev->id_entry = of_id->data;
+	hwtype = pdev->id_entry->driver_data;
 
 	if (mxc_gpio_hwtype) {
 		/*
@@ -426,6 +441,7 @@ static struct platform_driver mxc_gpio_driver = {
 	.driver		= {
 		.name	= "gpio-mxc",
 		.owner	= THIS_MODULE,
+		.of_match_table = mxc_gpio_dt_ids,
 	},
 	.probe		= mxc_gpio_probe,
 	.id_table	= mxc_gpio_devtype,
-- 
1.7.4.1