gpio/mxs: convert gpio-mxs to use basic_mmio_gpio library

The gpio-mxs controller complies with basic_mmio_gpio library.  This
patch converts the driver to use the library.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

drivers/gpio/Kconfig

@@ -101,6 +101,7 @@ config GPIO_MXC
 config GPIO_MXS
 	def_bool y
 	depends on ARCH_MXS
+	select GPIO_GENERIC
 
 config GPIO_PLAT_SAMSUNG
 	def_bool y

drivers/gpio/gpio-mxs.c

@@ -27,6 +27,7 @@
 #include <linux/gpio.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/basic_mmio_gpio.h>
 #include <mach/mxs.h>
 
 #define MXS_SET		0x4
@@ -54,7 +55,7 @@ struct mxs_gpio_port {
 	int irq;
 	int irq_high;
 	int virtual_irq_start;
-	struct gpio_chip chip;
+	struct bgpio_chip bgc;
 };
 
 /* Note: This driver assumes 32 GPIOs are handled in one register */
@@ -99,8 +100,6 @@ static void mxs_gpio_unmask_irq(struct irq_data *d)
 	set_gpio_irqenable(port, gpio & 0x1f, 1);
 }
 
-static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset);
-
 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
 {
 	u32 gpio = irq_to_gpio(d->irq);
@@ -203,61 +202,15 @@ static struct irq_chip gpio_irq_chip = {
 	.irq_set_wake = mxs_gpio_set_wake_irq,
 };
 
-static void mxs_set_gpio_direction(struct gpio_chip *chip, unsigned offset,
-				int dir)
-{
-	struct mxs_gpio_port *port =
-		container_of(chip, struct mxs_gpio_port, chip);
-	void __iomem *pin_addr = port->base + PINCTRL_DOE(port->id);
-
-	if (dir)
-		writel(1 << offset, pin_addr + MXS_SET);
-	else
-		writel(1 << offset, pin_addr + MXS_CLR);
-}
-
-static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset)
-{
-	struct mxs_gpio_port *port =
-		container_of(chip, struct mxs_gpio_port, chip);
-
-	return (readl(port->base + PINCTRL_DIN(port->id)) >> offset) & 1;
-}
-
-static void mxs_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
-{
-	struct mxs_gpio_port *port =
-		container_of(chip, struct mxs_gpio_port, chip);
-	void __iomem *pin_addr = port->base + PINCTRL_DOUT(port->id);
-
-	if (value)
-		writel(1 << offset, pin_addr + MXS_SET);
-	else
-		writel(1 << offset, pin_addr + MXS_CLR);
-}
-
-static int mxs_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
+static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
 {
+	struct bgpio_chip *bgc = to_bgpio_chip(gc);
 	struct mxs_gpio_port *port =
-		container_of(chip, struct mxs_gpio_port, chip);
+		container_of(bgc, struct mxs_gpio_port, bgc);
 
 	return port->virtual_irq_start + offset;
 }
 
-static int mxs_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
-{
-	mxs_set_gpio_direction(chip, offset, 0);
-	return 0;
-}
-
-static int mxs_gpio_direction_output(struct gpio_chip *chip,
-				     unsigned offset, int value)
-{
-	mxs_gpio_set(chip, offset, value);
-	mxs_set_gpio_direction(chip, offset, 1);
-	return 0;
-}
-
 static int __devinit mxs_gpio_probe(struct platform_device *pdev)
 {
 	static void __iomem *base;
@@ -322,21 +275,24 @@ static int __devinit mxs_gpio_probe(struct platform_device *pdev)
 	irq_set_chained_handler(port->irq, mxs_gpio_irq_handler);
 	irq_set_handler_data(port->irq, port);
 
-	/* register gpio chip */
-	port->chip.direction_input = mxs_gpio_direction_input;
-	port->chip.direction_output = mxs_gpio_direction_output;
-	port->chip.get = mxs_gpio_get;
-	port->chip.set = mxs_gpio_set;
-	port->chip.to_irq = mxs_gpio_to_irq;
-	port->chip.base = port->id * 32;
-	port->chip.ngpio = 32;
-
-	err = gpiochip_add(&port->chip);
+	err = bgpio_init(&port->bgc, &pdev->dev, 4,
+			 port->base + PINCTRL_DIN(port->id),
+			 port->base + PINCTRL_DOUT(port->id), NULL,
+			 port->base + PINCTRL_DOE(port->id), NULL, false);
 	if (err)
 		goto out_iounmap;
 
+	port->bgc.gc.to_irq = mxs_gpio_to_irq;
+	port->bgc.gc.base = port->id * 32;
+
+	err = gpiochip_add(&port->bgc.gc);
+	if (err)
+		goto out_bgpio_remove;
+
 	return 0;
 
+out_bgpio_remove:
+	bgpio_remove(&port->bgc);
 out_iounmap:
 	if (iores)
 		iounmap(port->base);