1 files changed, 70 insertions, 46 deletions

diff --git a/drivers/gpio/gpio-loongson.c b/drivers/gpio/gpio-loongson.c
index 92c4fe7b2677..16cfbe9e72fe 100644
--- a/drivers/gpio/gpio-loongson.c
+++ b/drivers/gpio/gpio-loongson.c
@@ -17,9 +17,11 @@
 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <linux/err.h>
+#include <linux/gpio/driver.h>
+#include <linux/platform_device.h>
+#include <linux/bitops.h>
 #include <asm/types.h>
 #include <loongson.h>
-#include <linux/gpio.h>
 
 #define STLS2F_N_GPIO		4
 #define STLS3A_N_GPIO		16
@@ -30,86 +32,108 @@
 #define LOONGSON_N_GPIO	STLS2F_N_GPIO
 #endif
 
+/*
+ * Offset into the register where we read lines, we write them from offset 0.
+ * This offset is the only thing that stand between us and using
+ * GPIO_GENERIC.
+ */
 #define LOONGSON_GPIO_IN_OFFSET	16
 
 static DEFINE_SPINLOCK(gpio_lock);
 
-static int loongson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
+static int loongson_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
 {
-	u32 temp;
-	u32 mask;
+	u32 val;
 
 	spin_lock(&gpio_lock);
-	mask = 1 << gpio;
-	temp = LOONGSON_GPIOIE;
-	temp |= mask;
-	LOONGSON_GPIOIE = temp;
+	val = LOONGSON_GPIODATA;
 	spin_unlock(&gpio_lock);
 
-	return 0;
+	return !!(val & BIT(gpio + LOONGSON_GPIO_IN_OFFSET));
 }
 
-static int loongson_gpio_direction_output(struct gpio_chip *chip,
-		unsigned gpio, int level)
+static void loongson_gpio_set_value(struct gpio_chip *chip,
+		unsigned gpio, int value)
+{
+	u32 val;
+
+	spin_lock(&gpio_lock);
+	val = LOONGSON_GPIODATA;
+	if (value)
+		val |= BIT(gpio);
+	else
+		val &= ~BIT(gpio);
+	LOONGSON_GPIODATA = val;
+	spin_unlock(&gpio_lock);
+}
+
+static int loongson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 {
 	u32 temp;
-	u32 mask;
 
-	gpio_set_value(gpio, level);
 	spin_lock(&gpio_lock);
-	mask = 1 << gpio;
 	temp = LOONGSON_GPIOIE;
-	temp &= (~mask);
+	temp |= BIT(gpio);
 	LOONGSON_GPIOIE = temp;
 	spin_unlock(&gpio_lock);
 
 	return 0;
 }
 
-static int loongson_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
+static int loongson_gpio_direction_output(struct gpio_chip *chip,
+		unsigned gpio, int level)
 {
-	u32 val;
-	u32 mask;
+	u32 temp;
 
-	mask = 1 << (gpio + LOONGSON_GPIO_IN_OFFSET);
+	loongson_gpio_set_value(chip, gpio, level);
 	spin_lock(&gpio_lock);
-	val = LOONGSON_GPIODATA;
+	temp = LOONGSON_GPIOIE;
+	temp &= ~BIT(gpio);
+	LOONGSON_GPIOIE = temp;
 	spin_unlock(&gpio_lock);
 
-	return (val & mask) != 0;
+	return 0;
 }
 
-static void loongson_gpio_set_value(struct gpio_chip *chip,
-		unsigned gpio, int value)
+static int loongson_gpio_probe(struct platform_device *pdev)
 {
-	u32 val;
-	u32 mask;
-
-	mask = 1 << gpio;
-
-	spin_lock(&gpio_lock);
-	val = LOONGSON_GPIODATA;
-	if (value)
-		val |= mask;
-	else
-		val &= (~mask);
-	LOONGSON_GPIODATA = val;
-	spin_unlock(&gpio_lock);
+	struct gpio_chip *gc;
+	struct device *dev = &pdev->dev;
+
+	gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
+	if (!gc)
+		return -ENOMEM;
+
+	gc->label = "loongson-gpio-chip";
+	gc->base = 0;
+	gc->ngpio = LOONGSON_N_GPIO;
+	gc->get = loongson_gpio_get_value;
+	gc->set = loongson_gpio_set_value;
+	gc->direction_input = loongson_gpio_direction_input;
+	gc->direction_output = loongson_gpio_direction_output;
+
+	return gpiochip_add_data(gc, NULL);
 }
 
-static struct gpio_chip loongson_chip = {
-	.label                  = "Loongson-gpio-chip",
-	.direction_input        = loongson_gpio_direction_input,
-	.get                    = loongson_gpio_get_value,
-	.direction_output       = loongson_gpio_direction_output,
-	.set                    = loongson_gpio_set_value,
-	.base			= 0,
-	.ngpio                  = LOONGSON_N_GPIO,
-	.can_sleep		= false,
+static struct platform_driver loongson_gpio_driver = {
+	.driver = {
+		.name = "loongson-gpio",
+	},
+	.probe = loongson_gpio_probe,
 };
 
 static int __init loongson_gpio_setup(void)
 {
-	return gpiochip_add_data(&loongson_chip, NULL);
+	struct platform_device *pdev;
+	int ret;
+
+	ret = platform_driver_register(&loongson_gpio_driver);
+	if (ret) {
+		pr_err("error registering loongson GPIO driver\n");
+		return ret;
+	}
+
+	pdev = platform_device_register_simple("loongson-gpio", -1, NULL, 0);
+	return PTR_ERR_OR_ZERO(pdev);
 }
 postcore_initcall(loongson_gpio_setup);