[U-Boot] [PATCH v3 5/6] dm: sunxi: Modify the GPIO driver to support driver model

[Simon Glass]

This adds driver model support to the sunxi GPIO driver, using the device
tree to trigger binding of the driver. The driver will still operate
without driver model too.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

Changes in v3:
- Put enabling of DM GPIO into sunxi-common.h

Changes in v2:
- Remove references to exynos and tegra
- Use the word 'bank' instead of 'port'

 drivers/gpio/sunxi_gpio.c      | 170 +++++++++++++++++++++++++++++++++++++++++
 include/configs/sunxi-common.h |   1 +
 2 files changed, 171 insertions(+)

diff --git a/drivers/gpio/sunxi_gpio.c b/drivers/gpio/sunxi_gpio.c
index 0c50a8f..44135e5 100644
--- a/drivers/gpio/sunxi_gpio.c
+++ b/drivers/gpio/sunxi_gpio.c
@@ -11,9 +11,25 @@
  */
 
 #include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <malloc.h>
 #include <asm/io.h>
 #include <asm/gpio.h>
+#include <dm/device-internal.h>
 
+DECLARE_GLOBAL_DATA_PTR;
+
+#define SUNXI_GPIOS_PER_BANK	SUNXI_GPIO_A_NR
+
+struct sunxi_gpio_platdata {
+	struct sunxi_gpio *regs;
+	const char *bank_name;	/* Name of bank, e.g. "B" */
+	int gpio_count;
+};
+
+#ifndef CONFIG_DM_GPIO
 static int sunxi_gpio_output(u32 pin, u32 val)
 {
 	u32 dat;
@@ -100,3 +116,157 @@ int sunxi_name_to_gpio(const char *name)
 		return -1;
 	return group * 32 + pin;
 }
+#endif
+
+#ifdef CONFIG_DM_GPIO
+static int sunxi_gpio_direction_input(struct udevice *dev, unsigned offset)
+{
+	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
+
+	sunxi_gpio_set_cfgbank(plat->regs, offset, SUNXI_GPIO_INPUT);
+
+	return 0;
+}
+
+static int sunxi_gpio_direction_output(struct udevice *dev, unsigned offset,
+				       int value)
+{
+	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
+	u32 num = GPIO_NUM(offset);
+
+	sunxi_gpio_set_cfgbank(plat->regs, offset, SUNXI_GPIO_OUTPUT);
+	clrsetbits_le32(&plat->regs->dat, 1 << num, value ? (1 << num) : 0);
+
+	return 0;
+}
+
+static int sunxi_gpio_get_value(struct udevice *dev, unsigned offset)
+{
+	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
+	u32 num = GPIO_NUM(offset);
+	unsigned dat;
+
+	dat = readl(&plat->regs->dat);
+	dat >>= num;
+
+	return dat & 0x1;
+}
+
+static int sunxi_gpio_set_value(struct udevice *dev, unsigned offset,
+				int value)
+{
+	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
+	u32 num = GPIO_NUM(offset);
+
+	clrsetbits_le32(&plat->regs->dat, 1 << num, value ? (1 << num) : 0);
+	return 0;
+}
+
+static int sunxi_gpio_get_function(struct udevice *dev, unsigned offset)
+{
+	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
+	int func;
+
+	func = sunxi_gpio_get_cfgbank(plat->regs, offset);
+	if (func == SUNXI_GPIO_OUTPUT)
+		return GPIOF_OUTPUT;
+	else if (func == SUNXI_GPIO_INPUT)
+		return GPIOF_INPUT;
+	else
+		return GPIOF_FUNC;
+}
+
+static const struct dm_gpio_ops gpio_sunxi_ops = {
+	.direction_input	= sunxi_gpio_direction_input,
+	.direction_output	= sunxi_gpio_direction_output,
+	.get_value		= sunxi_gpio_get_value,
+	.set_value		= sunxi_gpio_set_value,
+	.get_function		= sunxi_gpio_get_function,
+};
+
+/**
+ * Returns the name of a GPIO bank
+ *
+ * GPIO banks are named A, B, C, ...
+ *
+ * @bank:	Bank number (0, 1..n-1)
+ * @return allocated string containing the name
+ */
+static char *gpio_bank_name(int bank)
+{
+	char *name;
+
+	name = malloc(2);
+	if (name) {
+		name[0] = 'A' + bank;
+		name[1] = '\0';
+	}
+
+	return name;
+}
+
+static int gpio_sunxi_probe(struct udevice *dev)
+{
+	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
+	struct gpio_dev_priv *uc_priv = dev->uclass_priv;
+
+	/* Tell the uclass how many GPIOs we have */
+	if (plat) {
+		uc_priv->gpio_count = plat->gpio_count;
+		uc_priv->bank_name = plat->bank_name;
+	}
+
+	return 0;
+}
+/**
+ * We have a top-level GPIO device with no actual GPIOs. It has a child
+ * device for each Sunxi bank.
+ */
+static int gpio_sunxi_bind(struct udevice *parent)
+{
+	struct sunxi_gpio_platdata *plat = parent->platdata;
+	struct sunxi_gpio_reg *ctlr;
+	int bank;
+	int ret;
+
+	/* If this is a child device, there is nothing to do here */
+	if (plat)
+		return 0;
+
+	ctlr = (struct sunxi_gpio_reg *)fdtdec_get_addr(gd->fdt_blob,
+						   parent->of_offset, "reg");
+	for (bank = 0; bank < SUNXI_GPIO_BANKS; bank++) {
+		struct sunxi_gpio_platdata *plat;
+		struct udevice *dev;
+
+		plat = calloc(1, sizeof(*plat));
+		if (!plat)
+			return -ENOMEM;
+		plat->regs = &ctlr->gpio_bank[bank];
+		plat->bank_name = gpio_bank_name(bank);
+		plat->gpio_count = SUNXI_GPIOS_PER_BANK;
+
+		ret = device_bind(parent, parent->driver,
+					plat->bank_name, plat, -1, &dev);
+		if (ret)
+			return ret;
+		dev->of_offset = parent->of_offset;
+	}
+
+	return 0;
+}
+
+static const struct udevice_id sunxi_gpio_ids[] = {
+	{ .compatible = "allwinner,sun7i-a20-pinctrl" },
+	{ }
+};
+
+U_BOOT_DRIVER(gpio_sunxi) = {
+	.name	= "gpio_sunxi",
+	.id	= UCLASS_GPIO,
+	.ops	= &gpio_sunxi_ops,
+	.of_match = sunxi_gpio_ids,
+	.bind	= gpio_sunxi_bind,
+	.probe	= gpio_sunxi_probe,
+};
+#endif
diff --git a/include/configs/sunxi-common.h b/include/configs/sunxi-common.h
index 4d88991..316e7d9 100644
--- a/include/configs/sunxi-common.h
+++ b/include/configs/sunxi-common.h
@@ -29,6 +29,7 @@
 
 #if !defined(CONFIG_SPL_BUILD) && defined(CONFIG_DM)
 # define CONFIG_CMD_DM
+# define CONFIG_DM_GPIO
 #endif
 
 /*
-- 
2.1.0.rc2.206.gedb03e5