gpio/mxc: add device tree probe support

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

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

diff --git a/Documentation/devicetree/bindings/gpio/fsl-imx-gpio.txt b/Documentation/devicetree/bindings/gpio/fsl-imx-gpio.txt
new file mode 100644 (file)
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@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 3775dcc..89fda58 100644 (file)
--- 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 {
@@ -120,6 +122,13 @@ 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[IMX21_GPIO], },
+       { .compatible = "fsl,imx31-gpio", .data = &mxc_gpio_devtype[IMX31_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
@@ -302,7 +311,13 @@ 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) {
                /*
@@ -324,6 +339,7 @@ static void __devinit mxc_gpio_get_hw(struct platform_device *pdev)
 
 static int __devinit mxc_gpio_probe(struct platform_device *pdev)
 {
+       struct device_node *np = pdev->dev.of_node;
        struct mxc_gpio_port *port;
        struct resource *iores;
        int err;
@@ -334,8 +350,6 @@ static int __devinit mxc_gpio_probe(struct platform_device *pdev)
        if (!port)
                return -ENOMEM;
 
-       port->virtual_irq_start = MXC_GPIO_IRQ_START + pdev->id * 32;
-
        iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!iores) {
                err = -ENODEV;
@@ -365,9 +379,6 @@ static int __devinit mxc_gpio_probe(struct platform_device *pdev)
        writel(0, port->base + GPIO_IMR);
        writel(~0, port->base + GPIO_ISR);
 
-       /* gpio-mxc can be a generic irq chip */
-       mxc_gpio_init_gc(port);
-
        if (mxc_gpio_hwtype == IMX21_GPIO) {
                /* setup one handler for all GPIO interrupts */
                if (pdev->id == 0)
@@ -400,6 +411,16 @@ static int __devinit mxc_gpio_probe(struct platform_device *pdev)
        if (err)
                goto out_bgpio_remove;
 
+       /*
+        * In dt case, we use gpio number range dynamically
+        * allocated by gpio core.
+        */
+       port->virtual_irq_start = MXC_GPIO_IRQ_START + (np ? port->bgc.gc.base :
+                                                            pdev->id * 32);
+
+       /* gpio-mxc can be a generic irq chip */
+       mxc_gpio_init_gc(port);
+
        list_add_tail(&port->node, &mxc_gpio_ports);
 
        return 0;
@@ -420,6 +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,