diff options
Diffstat (limited to 'drivers/sh/pfc-gpio.c')
-rw-r--r-- | drivers/sh/pfc-gpio.c | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/drivers/sh/pfc-gpio.c b/drivers/sh/pfc-gpio.c new file mode 100644 index 000000000000..d74e5a96024b --- /dev/null +++ b/drivers/sh/pfc-gpio.c @@ -0,0 +1,309 @@ +/* + * SuperH Pin Function Controller GPIO driver. + * + * Copyright (C) 2008 Magnus Damm + * Copyright (C) 2009 - 2012 Paul Mundt + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/init.h> +#include <linux/gpio.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +struct sh_pfc_chip { + struct sh_pfc *pfc; + struct gpio_chip gpio_chip; +}; + +static struct sh_pfc_chip *gpio_to_pfc_chip(struct gpio_chip *gc) +{ + return container_of(gc, struct sh_pfc_chip, gpio_chip); +} + +static struct sh_pfc *gpio_to_pfc(struct gpio_chip *gc) +{ + return gpio_to_pfc_chip(gc)->pfc; +} + +static int sh_gpio_request(struct gpio_chip *gc, unsigned offset) +{ + struct sh_pfc *pfc = gpio_to_pfc(gc); + struct pinmux_data_reg *dummy; + unsigned long flags; + int i, ret, pinmux_type; + + ret = -EINVAL; + + if (!pfc) + goto err_out; + + spin_lock_irqsave(&pfc->lock, flags); + + if ((pfc->gpios[offset].flags & PINMUX_FLAG_TYPE) != PINMUX_TYPE_NONE) + goto err_unlock; + + /* setup pin function here if no data is associated with pin */ + + if (sh_pfc_get_data_reg(pfc, offset, &dummy, &i) != 0) + pinmux_type = PINMUX_TYPE_FUNCTION; + else + pinmux_type = PINMUX_TYPE_GPIO; + + if (pinmux_type == PINMUX_TYPE_FUNCTION) { + if (sh_pfc_config_gpio(pfc, offset, + pinmux_type, + GPIO_CFG_DRYRUN) != 0) + goto err_unlock; + + if (sh_pfc_config_gpio(pfc, offset, + pinmux_type, + GPIO_CFG_REQ) != 0) + BUG(); + } + + pfc->gpios[offset].flags &= ~PINMUX_FLAG_TYPE; + pfc->gpios[offset].flags |= pinmux_type; + + ret = 0; + err_unlock: + spin_unlock_irqrestore(&pfc->lock, flags); + err_out: + return ret; +} + +static void sh_gpio_free(struct gpio_chip *gc, unsigned offset) +{ + struct sh_pfc *pfc = gpio_to_pfc(gc); + unsigned long flags; + int pinmux_type; + + if (!pfc) + return; + + spin_lock_irqsave(&pfc->lock, flags); + + pinmux_type = pfc->gpios[offset].flags & PINMUX_FLAG_TYPE; + sh_pfc_config_gpio(pfc, offset, pinmux_type, GPIO_CFG_FREE); + pfc->gpios[offset].flags &= ~PINMUX_FLAG_TYPE; + pfc->gpios[offset].flags |= PINMUX_TYPE_NONE; + + spin_unlock_irqrestore(&pfc->lock, flags); +} + +static int sh_gpio_direction_input(struct gpio_chip *gc, unsigned offset) +{ + struct sh_pfc *pfc = gpio_to_pfc(gc); + unsigned long flags; + int ret; + + spin_lock_irqsave(&pfc->lock, flags); + ret = sh_pfc_set_direction(pfc, offset, PINMUX_TYPE_INPUT); + spin_unlock_irqrestore(&pfc->lock, flags); + + return ret; +} + +static void sh_gpio_set_value(struct sh_pfc *pfc, unsigned gpio, int value) +{ + struct pinmux_data_reg *dr = NULL; + int bit = 0; + + if (!pfc || sh_pfc_get_data_reg(pfc, gpio, &dr, &bit) != 0) + BUG(); + else + sh_pfc_write_bit(dr, bit, value); +} + +static int sh_gpio_direction_output(struct gpio_chip *gc, unsigned offset, + int value) +{ + struct sh_pfc *pfc = gpio_to_pfc(gc); + unsigned long flags; + int ret; + + sh_gpio_set_value(pfc, offset, value); + + spin_lock_irqsave(&pfc->lock, flags); + ret = sh_pfc_set_direction(pfc, offset, PINMUX_TYPE_OUTPUT); + spin_unlock_irqrestore(&pfc->lock, flags); + + return ret; +} + +static int sh_gpio_get_value(struct sh_pfc *pfc, unsigned gpio) +{ + struct pinmux_data_reg *dr = NULL; + int bit = 0; + + if (!pfc || sh_pfc_get_data_reg(pfc, gpio, &dr, &bit) != 0) + return -EINVAL; + + return sh_pfc_read_bit(dr, bit); +} + +static int sh_gpio_get(struct gpio_chip *gc, unsigned offset) +{ + return sh_gpio_get_value(gpio_to_pfc(gc), offset); +} + +static void sh_gpio_set(struct gpio_chip *gc, unsigned offset, int value) +{ + sh_gpio_set_value(gpio_to_pfc(gc), offset, value); +} + +static int sh_gpio_to_irq(struct gpio_chip *gc, unsigned offset) +{ + struct sh_pfc *pfc = gpio_to_pfc(gc); + pinmux_enum_t enum_id; + pinmux_enum_t *enum_ids; + int i, k, pos; + + pos = 0; + enum_id = 0; + while (1) { + pos = sh_pfc_gpio_to_enum(pfc, offset, pos, &enum_id); + if (pos <= 0 || !enum_id) + break; + + for (i = 0; i < pfc->gpio_irq_size; i++) { + enum_ids = pfc->gpio_irq[i].enum_ids; + for (k = 0; enum_ids[k]; k++) { + if (enum_ids[k] == enum_id) + return pfc->gpio_irq[i].irq; + } + } + } + + return -ENOSYS; +} + +static void sh_pfc_gpio_setup(struct sh_pfc_chip *chip) +{ + struct sh_pfc *pfc = chip->pfc; + struct gpio_chip *gc = &chip->gpio_chip; + + gc->request = sh_gpio_request; + gc->free = sh_gpio_free; + gc->direction_input = sh_gpio_direction_input; + gc->get = sh_gpio_get; + gc->direction_output = sh_gpio_direction_output; + gc->set = sh_gpio_set; + gc->to_irq = sh_gpio_to_irq; + + WARN_ON(pfc->first_gpio != 0); /* needs testing */ + + gc->label = pfc->name; + gc->owner = THIS_MODULE; + gc->base = pfc->first_gpio; + gc->ngpio = (pfc->last_gpio - pfc->first_gpio) + 1; +} + +int sh_pfc_register_gpiochip(struct sh_pfc *pfc) +{ + struct sh_pfc_chip *chip; + int ret; + + chip = kzalloc(sizeof(struct sh_pfc_chip), GFP_KERNEL); + if (unlikely(!chip)) + return -ENOMEM; + + chip->pfc = pfc; + + sh_pfc_gpio_setup(chip); + + ret = gpiochip_add(&chip->gpio_chip); + if (unlikely(ret < 0)) + kfree(chip); + + pr_info("%s handling gpio %d -> %d\n", + pfc->name, pfc->first_gpio, pfc->last_gpio); + + return ret; +} +EXPORT_SYMBOL_GPL(sh_pfc_register_gpiochip); + +static int sh_pfc_gpio_match(struct gpio_chip *gc, void *data) +{ + return !!strstr(gc->label, data); +} + +static int __devinit sh_pfc_gpio_probe(struct platform_device *pdev) +{ + struct sh_pfc_chip *chip; + struct gpio_chip *gc; + + gc = gpiochip_find("_pfc", sh_pfc_gpio_match); + if (unlikely(!gc)) { + pr_err("Cant find gpio chip\n"); + return -ENODEV; + } + + chip = gpio_to_pfc_chip(gc); + platform_set_drvdata(pdev, chip); + + pr_info("attaching to GPIO chip %s\n", chip->pfc->name); + + return 0; +} + +static int __devexit sh_pfc_gpio_remove(struct platform_device *pdev) +{ + struct sh_pfc_chip *chip = platform_get_drvdata(pdev); + int ret; + + ret = gpiochip_remove(&chip->gpio_chip); + if (unlikely(ret < 0)) + return ret; + + kfree(chip); + return 0; +} + +static struct platform_driver sh_pfc_gpio_driver = { + .probe = sh_pfc_gpio_probe, + .remove = __devexit_p(sh_pfc_gpio_remove), + .driver = { + .name = KBUILD_MODNAME, + .owner = THIS_MODULE, + }, +}; + +static struct platform_device sh_pfc_gpio_device = { + .name = KBUILD_MODNAME, + .id = -1, +}; + +static int __init sh_pfc_gpio_init(void) +{ + int rc; + + rc = platform_driver_register(&sh_pfc_gpio_driver); + if (likely(!rc)) { + rc = platform_device_register(&sh_pfc_gpio_device); + if (unlikely(rc)) + platform_driver_unregister(&sh_pfc_gpio_driver); + } + + return rc; +} + +static void __exit sh_pfc_gpio_exit(void) +{ + platform_device_unregister(&sh_pfc_gpio_device); + platform_driver_unregister(&sh_pfc_gpio_driver); +} + +module_init(sh_pfc_gpio_init); +module_exit(sh_pfc_gpio_exit); + +MODULE_AUTHOR("Magnus Damm, Paul Mundt"); +MODULE_DESCRIPTION("GPIO driver for SuperH pin function controller"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:pfc-gpio"); |