[U-Boot] [PATCH] dm:gpio:mxc get configuration from dtb

[Peng Fan]

This patch supports getting gpios' configuration from dtb.
CONFIG_OF_CONTROL is used to indicated which part is for device tree,
and which is not.

This patch is already tested on mx6sxsabresd board. Since device tree
has not been upstreamed, if want to test this patch. The followings
need to be done.
 + pieces of code does not gpio_request when using gpio_direction_xxx and
   etc, need to request gpio.
 + move the gpio settings from board_early_init_f to board_init
 + define CONFIG_DM ,CONFIG_DM_GPIO and CONFIG_OF_CONTROL
 + Add device tree file and do related configuration in
   `make ARCH=arm menuconfig`

Signed-off-by: Peng Fan <Peng.Fan at freescale.com>
---
 drivers/gpio/mxc_gpio.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)

diff --git a/drivers/gpio/mxc_gpio.c b/drivers/gpio/mxc_gpio.c
index 8bb9e39..8603068 100644
--- a/drivers/gpio/mxc_gpio.c
+++ b/drivers/gpio/mxc_gpio.c
@@ -14,6 +14,10 @@
 #include <asm/arch/imx-regs.h>
 #include <asm/gpio.h>
 #include <asm/io.h>
+#ifdef CONFIG_OF_CONTROL
+#include <fdtdec.h>
+DECLARE_GLOBAL_DATA_PTR;
+#endif
 
 enum mxc_gpio_direction {
 	MXC_GPIO_DIRECTION_IN,
@@ -258,6 +262,7 @@ static const struct dm_gpio_ops gpio_mxc_ops = {
 	.get_function		= mxc_gpio_get_function,
 };
 
+#ifndef CONFIG_OF_CONTROL
 static const struct mxc_gpio_plat mxc_plat[] = {
 	{ (struct gpio_regs *)GPIO1_BASE_ADDR },
 	{ (struct gpio_regs *)GPIO2_BASE_ADDR },
@@ -274,6 +279,7 @@ static const struct mxc_gpio_plat mxc_plat[] = {
 	{ (struct gpio_regs *)GPIO7_BASE_ADDR },
 #endif
 };
+#endif
 
 static int mxc_gpio_probe(struct udevice *dev)
 {
@@ -283,7 +289,19 @@ static int mxc_gpio_probe(struct udevice *dev)
 	int banknum;
 	char name[18], *str;
 
+#ifdef CONFIG_OF_CONTROL
+	/*
+	 * In dts file add:
+	 * aliases {
+	 *	gpio0 = &gpio1;
+	 *	gpio1 = &gpio2;
+	 *	.....
+	 * };
+	 * Then set banknum accoring dev's seq number. */
+	banknum = dev->seq;
+#else
 	banknum = plat - mxc_plat;
+#endif
 	sprintf(name, "GPIO%d_", banknum + 1);
 	str = strdup(name);
 	if (!str)
@@ -295,14 +313,71 @@ static int mxc_gpio_probe(struct udevice *dev)
 	return 0;
 }
 
+#ifdef CONFIG_OF_CONTROL
+static int mxc_gpio_bind(struct udevice *device)
+{
+	struct mxc_gpio_plat *plat = device->platdata;
+	struct gpio_regs *ctrl;
+
+	if (plat)
+		return 0;
+	/*
+	 * In the dts file, gpiox bank are as following:
+	 *	gpio1: gpio at 0209c000 {
+	 *		compatible = "fsl,imx6q-gpio", "fsl,imx35-gpio";
+	 *		reg = <0x0209c000 0x4000>;
+	 *		interrupts = <0 66 0x04 0 67 0x04>;
+	 *		gpio-controller;
+	 *		#gpio-cells = <2>;
+	 *		interrupt-controller;
+	 *		#interrupt-cells = <2>;
+	 *	};
+	 *
+	 *	gpio2: gpio at 020a0000 {
+	 *		compatible = "fsl,imx6q-gpio", "fsl,imx35-gpio";
+	 *		reg = <0x020a0000 0x4000>;
+	 *		interrupts = <0 68 0x04 0 69 0x04>;
+	 *		gpio-controller;
+	 *		#gpio-cells = <2>;
+	 *		interrupt-controller;
+	 *		#interrupt-cells = <2>;
+	 *	};
+	 *
+	 * gpio1 is the 1st bank, gpio2 is the 2nd bank and gpio3 ....
+	 */
+
+	ctrl = (struct gpio_regs *)fdtdec_get_addr(gd->fdt_blob,
+						   device->of_offset, "reg");
+	plat = calloc(1, sizeof(*plat));
+	if (!plat)
+		return -ENOMEM;
+
+	plat->regs = ctrl;
+
+	device->platdata = plat;
+
+	return 0;
+}
+
+static const struct udevice_id mxc_gpio_ids[] = {
+	{ .compatible = "fsl,imx35-gpio" },
+	{ }
+};
+#endif
+
 U_BOOT_DRIVER(gpio_mxc) = {
 	.name	= "gpio_mxc",
 	.id	= UCLASS_GPIO,
 	.ops	= &gpio_mxc_ops,
 	.probe	= mxc_gpio_probe,
 	.priv_auto_alloc_size = sizeof(struct mxc_bank_info),
+#ifdef CONFIG_OF_CONTROL
+	.of_match = mxc_gpio_ids,
+	.bind	= mxc_gpio_bind,
+#endif
 };
 
+#ifndef CONFIG_OF_CONTROL
 U_BOOT_DEVICES(mxc_gpios) = {
 	{ "gpio_mxc", &mxc_plat[0] },
 	{ "gpio_mxc", &mxc_plat[1] },
@@ -320,3 +395,4 @@ U_BOOT_DEVICES(mxc_gpios) = {
 #endif
 };
 #endif
+#endif
-- 
1.8.4