MIPS: AR7: Implement gpiolib
This patch implements gpiolib for the AR7 SoC.
Signed-off-by: Florian Fainelli <florian@openwrt.org>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/816/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/ar7/gpio.c b/arch/mips/ar7/gpio.c
index 74e14a3..0e9f4e1 100644
--- a/arch/mips/ar7/gpio.c
+++ b/arch/mips/ar7/gpio.c
@@ -1,6 +1,7 @@
/*
* Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
* Copyright (C) 2007 Eugene Konev <ejka@openwrt.org>
+ * Copyright (C) 2009 Florian Fainelli <florian@openwrt.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -18,31 +19,113 @@
*/
#include <linux/module.h>
+#include <linux/gpio.h>
#include <asm/mach-ar7/gpio.h>
-static const char *ar7_gpio_list[AR7_GPIO_MAX];
+struct ar7_gpio_chip {
+ void __iomem *regs;
+ struct gpio_chip chip;
+};
-int gpio_request(unsigned gpio, const char *label)
+static int ar7_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
- if (gpio >= AR7_GPIO_MAX)
- return -EINVAL;
+ struct ar7_gpio_chip *gpch =
+ container_of(chip, struct ar7_gpio_chip, chip);
+ void __iomem *gpio_in = gpch->regs + AR7_GPIO_INPUT;
- if (ar7_gpio_list[gpio])
- return -EBUSY;
+ return readl(gpio_in) & (1 << gpio);
+}
- if (label)
- ar7_gpio_list[gpio] = label;
- else
- ar7_gpio_list[gpio] = "busy";
+static void ar7_gpio_set_value(struct gpio_chip *chip,
+ unsigned gpio, int value)
+{
+ struct ar7_gpio_chip *gpch =
+ container_of(chip, struct ar7_gpio_chip, chip);
+ void __iomem *gpio_out = gpch->regs + AR7_GPIO_OUTPUT;
+ unsigned tmp;
+
+ tmp = readl(gpio_out) & ~(1 << gpio);
+ if (value)
+ tmp |= 1 << gpio;
+ writel(tmp, gpio_out);
+}
+
+static int ar7_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
+{
+ struct ar7_gpio_chip *gpch =
+ container_of(chip, struct ar7_gpio_chip, chip);
+ void __iomem *gpio_dir = gpch->regs + AR7_GPIO_DIR;
+
+ writel(readl(gpio_dir) | (1 << gpio), gpio_dir);
return 0;
}
-EXPORT_SYMBOL(gpio_request);
-void gpio_free(unsigned gpio)
+static int ar7_gpio_direction_output(struct gpio_chip *chip,
+ unsigned gpio, int value)
{
- BUG_ON(!ar7_gpio_list[gpio]);
- ar7_gpio_list[gpio] = NULL;
+ struct ar7_gpio_chip *gpch =
+ container_of(chip, struct ar7_gpio_chip, chip);
+ void __iomem *gpio_dir = gpch->regs + AR7_GPIO_DIR;
+
+ ar7_gpio_set_value(chip, gpio, value);
+ writel(readl(gpio_dir) & ~(1 << gpio), gpio_dir);
+
+ return 0;
}
-EXPORT_SYMBOL(gpio_free);
+
+static struct ar7_gpio_chip ar7_gpio_chip = {
+ .chip = {
+ .label = "ar7-gpio",
+ .direction_input = ar7_gpio_direction_input,
+ .direction_output = ar7_gpio_direction_output,
+ .set = ar7_gpio_set_value,
+ .get = ar7_gpio_get_value,
+ .base = 0,
+ .ngpio = AR7_GPIO_MAX,
+ }
+};
+
+int ar7_gpio_enable(unsigned gpio)
+{
+ void __iomem *gpio_en = ar7_gpio_chip.regs + AR7_GPIO_ENABLE;
+
+ writel(readl(gpio_en) | (1 << gpio), gpio_en);
+
+ return 0;
+}
+EXPORT_SYMBOL(ar7_gpio_enable);
+
+int ar7_gpio_disable(unsigned gpio)
+{
+ void __iomem *gpio_en = ar7_gpio_chip.regs + AR7_GPIO_ENABLE;
+
+ writel(readl(gpio_en) & ~(1 << gpio), gpio_en);
+
+ return 0;
+}
+EXPORT_SYMBOL(ar7_gpio_disable);
+
+static int __init ar7_gpio_init(void)
+{
+ int ret;
+
+ ar7_gpio_chip.regs = ioremap_nocache(AR7_REGS_GPIO,
+ AR7_REGS_GPIO + 0x10);
+
+ if (!ar7_gpio_chip.regs) {
+ printk(KERN_ERR "ar7-gpio: failed to ioremap regs\n");
+ return -ENOMEM;
+ }
+
+ ret = gpiochip_add(&ar7_gpio_chip.chip);
+ if (ret) {
+ printk(KERN_ERR "ar7-gpio: failed to add gpiochip\n");
+ return ret;
+ }
+ printk(KERN_INFO "ar7-gpio: registered %d GPIOs\n",
+ ar7_gpio_chip.chip.ngpio);
+ return ret;
+}
+arch_initcall(ar7_gpio_init);