diff options
Diffstat (limited to 'arch/powerpc/sysdev/qe_lib/gpio.c')
| -rw-r--r-- | arch/powerpc/sysdev/qe_lib/gpio.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/qe_lib/gpio.c b/arch/powerpc/sysdev/qe_lib/gpio.c new file mode 100644 index 000000000000..8e5a0bc36d0b --- /dev/null +++ b/arch/powerpc/sysdev/qe_lib/gpio.c @@ -0,0 +1,149 @@ +/* + * QUICC Engine GPIOs + * + * Copyright (c) MontaVista Software, Inc. 2008. + * + * Author: Anton Vorontsov <avorontsov@ru.mvista.com> + * + * 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 the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#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> +#include <asm/qe.h> + +struct qe_gpio_chip { + struct of_mm_gpio_chip mm_gc; + spinlock_t lock; + + /* shadowed data register to clear/set bits safely */ + u32 cpdata; +}; + +static inline struct qe_gpio_chip * +to_qe_gpio_chip(struct of_mm_gpio_chip *mm_gc) +{ + return container_of(mm_gc, struct qe_gpio_chip, mm_gc); +} + +static void qe_gpio_save_regs(struct of_mm_gpio_chip *mm_gc) +{ + struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc); + struct qe_pio_regs __iomem *regs = mm_gc->regs; + + qe_gc->cpdata = in_be32(®s->cpdata); +} + +static int qe_gpio_get(struct gpio_chip *gc, unsigned int gpio) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + struct qe_pio_regs __iomem *regs = mm_gc->regs; + u32 pin_mask = 1 << (QE_PIO_PINS - 1 - gpio); + + return in_be32(®s->cpdata) & pin_mask; +} + +static void qe_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc); + struct qe_pio_regs __iomem *regs = mm_gc->regs; + unsigned long flags; + u32 pin_mask = 1 << (QE_PIO_PINS - 1 - gpio); + + spin_lock_irqsave(&qe_gc->lock, flags); + + if (val) + qe_gc->cpdata |= pin_mask; + else + qe_gc->cpdata &= ~pin_mask; + + out_be32(®s->cpdata, qe_gc->cpdata); + + spin_unlock_irqrestore(&qe_gc->lock, flags); +} + +static int qe_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc); + unsigned long flags; + + spin_lock_irqsave(&qe_gc->lock, flags); + + __par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_IN, 0, 0, 0); + + spin_unlock_irqrestore(&qe_gc->lock, flags); + + return 0; +} + +static int qe_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc); + unsigned long flags; + + spin_lock_irqsave(&qe_gc->lock, flags); + + __par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_OUT, 0, 0, 0); + + spin_unlock_irqrestore(&qe_gc->lock, flags); + + qe_gpio_set(gc, gpio, val); + + return 0; +} + +static int __init qe_add_gpiochips(void) +{ + struct device_node *np; + + for_each_compatible_node(np, NULL, "fsl,mpc8323-qe-pario-bank") { + int ret; + struct qe_gpio_chip *qe_gc; + struct of_mm_gpio_chip *mm_gc; + struct of_gpio_chip *of_gc; + struct gpio_chip *gc; + + qe_gc = kzalloc(sizeof(*qe_gc), GFP_KERNEL); + if (!qe_gc) { + ret = -ENOMEM; + goto err; + } + + spin_lock_init(&qe_gc->lock); + + mm_gc = &qe_gc->mm_gc; + of_gc = &mm_gc->of_gc; + gc = &of_gc->gc; + + mm_gc->save_regs = qe_gpio_save_regs; + of_gc->gpio_cells = 2; + gc->ngpio = QE_PIO_PINS; + gc->direction_input = qe_gpio_dir_in; + gc->direction_output = qe_gpio_dir_out; + gc->get = qe_gpio_get; + gc->set = qe_gpio_set; + + ret = of_mm_gpiochip_add(np, mm_gc); + if (ret) + goto err; + continue; +err: + pr_err("%s: registration failed with status %d\n", + np->full_name, ret); + kfree(qe_gc); + /* try others anyway */ + } + return 0; +} +arch_initcall(qe_add_gpiochips); |