dm:gpio:mxc add DT support

This patch add DT support for mxc gpio driver.

There are one place using CONFIG_OF_CONTROL macro.
1. The U_BOOT_DEVICES and mxc_plat array are complied out. To DT,
   platdata is alloced using calloc, so there is no need to use mxc_plat.

The following situations are tested, and all work fine:
1. with DM, without DT
2. with DM and DT
3. without DM
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`
These will be done in future patches by step.

Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
Acked-by: Simon Glass <sjg@chromium.org>

drivers/gpio/mxc_gpio.c

@@ -151,6 +151,9 @@ int gpio_direction_output(unsigned gpio, int value)
 #endif
 
 #ifdef CONFIG_DM_GPIO
+#include <fdtdec.h>
+DECLARE_GLOBAL_DATA_PTR;
+
 static int mxc_gpio_is_output(struct gpio_regs *regs, int offset)
 {
 	u32 val;
@@ -259,23 +262,6 @@ static const struct dm_gpio_ops gpio_mxc_ops = {
 	.get_function		= mxc_gpio_get_function,
 };
 
-static const struct mxc_gpio_plat mxc_plat[] = {
-	{ 0, (struct gpio_regs *)GPIO1_BASE_ADDR },
-	{ 1, (struct gpio_regs *)GPIO2_BASE_ADDR },
-	{ 2, (struct gpio_regs *)GPIO3_BASE_ADDR },
-#if defined(CONFIG_MX25) || defined(CONFIG_MX27) || defined(CONFIG_MX51) || \
-		defined(CONFIG_MX53) || defined(CONFIG_MX6)
-	{ 3, (struct gpio_regs *)GPIO4_BASE_ADDR },
-#endif
-#if defined(CONFIG_MX27) || defined(CONFIG_MX53) || defined(CONFIG_MX6)
-	{ 4, (struct gpio_regs *)GPIO5_BASE_ADDR },
-	{ 5, (struct gpio_regs *)GPIO6_BASE_ADDR },
-#endif
-#if defined(CONFIG_MX53) || defined(CONFIG_MX6)
-	{ 6, (struct gpio_regs *)GPIO7_BASE_ADDR },
-#endif
-};
-
 static int mxc_gpio_probe(struct udevice *dev)
 {
 	struct mxc_bank_info *bank = dev_get_priv(dev);
@@ -296,12 +282,72 @@ static int mxc_gpio_probe(struct udevice *dev)
 	return 0;
 }
 
+static int mxc_gpio_bind(struct udevice *dev)
+{
+	struct mxc_gpio_plat *plat = dev->platdata;
+	fdt_addr_t addr;
+
+	/*
+	 * If platdata already exsits, directly return.
+	 * Actually only when DT is not supported, platdata
+	 * is statically initialized in U_BOOT_DEVICES.Here
+	 * will return.
+	 */
+	if (plat)
+		return 0;
+
+	addr = dev_get_addr(dev);
+	if (addr == FDT_ADDR_T_NONE)
+		return -ENODEV;
+
+	/*
+	 * TODO:
+	 * When every board is converted to driver model and DT is supported,
+	 * this can be done by auto-alloc feature, but not using calloc
+	 * to alloc memory for platdata.
+	 */
+	plat = calloc(1, sizeof(*plat));
+	if (!plat)
+		return -ENOMEM;
+
+	plat->regs = (struct gpio_regs *)addr;
+	plat->bank_index = dev->req_seq;
+	dev->platdata = plat;
+
+	return 0;
+}
+
+static const struct udevice_id mxc_gpio_ids[] = {
+	{ .compatible = "fsl,imx35-gpio" },
+	{ }
+};
+
 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),
+	.of_match = mxc_gpio_ids,
+	.bind	= mxc_gpio_bind,
+};
+
+#ifndef CONFIG_OF_CONTROL
+static const struct mxc_gpio_plat mxc_plat[] = {
+	{ 0, (struct gpio_regs *)GPIO1_BASE_ADDR },
+	{ 1, (struct gpio_regs *)GPIO2_BASE_ADDR },
+	{ 2, (struct gpio_regs *)GPIO3_BASE_ADDR },
+#if defined(CONFIG_MX25) || defined(CONFIG_MX27) || defined(CONFIG_MX51) || \
+		defined(CONFIG_MX53) || defined(CONFIG_MX6)
+	{ 3, (struct gpio_regs *)GPIO4_BASE_ADDR },
+#endif
+#if defined(CONFIG_MX27) || defined(CONFIG_MX53) || defined(CONFIG_MX6)
+	{ 4, (struct gpio_regs *)GPIO5_BASE_ADDR },
+	{ 5, (struct gpio_regs *)GPIO6_BASE_ADDR },
+#endif
+#if defined(CONFIG_MX53) || defined(CONFIG_MX6)
+	{ 6, (struct gpio_regs *)GPIO7_BASE_ADDR },
+#endif
 };
 
 U_BOOT_DEVICES(mxc_gpios) = {
@@ -321,3 +367,4 @@ U_BOOT_DEVICES(mxc_gpios) = {
 #endif
 };
 #endif
+#endif