diff options
Diffstat (limited to 'arch/powerpc/sysdev/mpc8xxx_gpio.c')
| -rw-r--r-- | arch/powerpc/sysdev/mpc8xxx_gpio.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/mpc8xxx_gpio.c b/arch/powerpc/sysdev/mpc8xxx_gpio.c new file mode 100644 index 000000000000..103eace36194 --- /dev/null +++ b/arch/powerpc/sysdev/mpc8xxx_gpio.c @@ -0,0 +1,171 @@ +/* + * GPIOs on MPC8349/8572/8610 and compatible + * + * Copyright (C) 2008 Peter Korsgaard <jacmet@sunsite.dk> + * + * This file is licensed under the terms of the GNU General Public License + * version 2. This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/gpio.h> + +#define MPC8XXX_GPIO_PINS 32 + +#define GPIO_DIR 0x00 +#define GPIO_ODR 0x04 +#define GPIO_DAT 0x08 +#define GPIO_IER 0x0c +#define GPIO_IMR 0x10 +#define GPIO_ICR 0x14 + +struct mpc8xxx_gpio_chip { + struct of_mm_gpio_chip mm_gc; + spinlock_t lock; + + /* + * shadowed data register to be able to clear/set output pins in + * open drain mode safely + */ + u32 data; +}; + +static inline u32 mpc8xxx_gpio2mask(unsigned int gpio) +{ + return 1u << (MPC8XXX_GPIO_PINS - 1 - gpio); +} + +static inline struct mpc8xxx_gpio_chip * +to_mpc8xxx_gpio_chip(struct of_mm_gpio_chip *mm) +{ + return container_of(mm, struct mpc8xxx_gpio_chip, mm_gc); +} + +static void mpc8xxx_gpio_save_regs(struct of_mm_gpio_chip *mm) +{ + struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm); + + mpc8xxx_gc->data = in_be32(mm->regs + GPIO_DAT); +} + +static int mpc8xxx_gpio_get(struct gpio_chip *gc, unsigned int gpio) +{ + struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc); + + return in_be32(mm->regs + GPIO_DAT) & mpc8xxx_gpio2mask(gpio); +} + +static void mpc8xxx_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val) +{ + struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc); + struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm); + unsigned long flags; + + spin_lock_irqsave(&mpc8xxx_gc->lock, flags); + + if (val) + mpc8xxx_gc->data |= mpc8xxx_gpio2mask(gpio); + else + mpc8xxx_gc->data &= ~mpc8xxx_gpio2mask(gpio); + + out_be32(mm->regs + GPIO_DAT, mpc8xxx_gc->data); + + spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags); +} + +static int mpc8xxx_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio) +{ + struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc); + struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm); + unsigned long flags; + + spin_lock_irqsave(&mpc8xxx_gc->lock, flags); + + clrbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio)); + + spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags); + + return 0; +} + +static int mpc8xxx_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val) +{ + struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc); + struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm); + unsigned long flags; + + mpc8xxx_gpio_set(gc, gpio, val); + + spin_lock_irqsave(&mpc8xxx_gc->lock, flags); + + setbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio)); + + spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags); + + return 0; +} + +static void __init mpc8xxx_add_controller(struct device_node *np) +{ + struct mpc8xxx_gpio_chip *mpc8xxx_gc; + struct of_mm_gpio_chip *mm_gc; + struct of_gpio_chip *of_gc; + struct gpio_chip *gc; + int ret; + + mpc8xxx_gc = kzalloc(sizeof(*mpc8xxx_gc), GFP_KERNEL); + if (!mpc8xxx_gc) { + ret = -ENOMEM; + goto err; + } + + spin_lock_init(&mpc8xxx_gc->lock); + + mm_gc = &mpc8xxx_gc->mm_gc; + of_gc = &mm_gc->of_gc; + gc = &of_gc->gc; + + mm_gc->save_regs = mpc8xxx_gpio_save_regs; + of_gc->gpio_cells = 2; + gc->ngpio = MPC8XXX_GPIO_PINS; + gc->direction_input = mpc8xxx_gpio_dir_in; + gc->direction_output = mpc8xxx_gpio_dir_out; + gc->get = mpc8xxx_gpio_get; + gc->set = mpc8xxx_gpio_set; + + ret = of_mm_gpiochip_add(np, mm_gc); + if (ret) + goto err; + + return; + +err: + pr_err("%s: registration failed with status %d\n", + np->full_name, ret); + kfree(mpc8xxx_gc); + + return; +} + +static int __init mpc8xxx_add_gpiochips(void) +{ + struct device_node *np; + + for_each_compatible_node(np, NULL, "fsl,mpc8349-gpio") + mpc8xxx_add_controller(np); + + for_each_compatible_node(np, NULL, "fsl,mpc8572-gpio") + mpc8xxx_add_controller(np); + + for_each_compatible_node(np, NULL, "fsl,mpc8610-gpio") + mpc8xxx_add_controller(np); + + return 0; +} +arch_initcall(mpc8xxx_add_gpiochips); |