diff options
Diffstat (limited to 'drivers/gpio/ab8500-gpio.c')
| -rw-r--r-- | drivers/gpio/ab8500-gpio.c | 522 |
1 files changed, 522 insertions, 0 deletions
diff --git a/drivers/gpio/ab8500-gpio.c b/drivers/gpio/ab8500-gpio.c new file mode 100644 index 00000000000..e7b834d054b --- /dev/null +++ b/drivers/gpio/ab8500-gpio.c @@ -0,0 +1,522 @@ +/* + * Copyright (C) ST-Ericsson SA 2011 + * + * Author: BIBEK BASU <bibek.basu@stericsson.com> + * License terms: GNU General Public License (GPL) version 2 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/gpio.h> +#include <linux/irq.h> +#include <linux/interrupt.h> +#include <linux/mfd/ab8500.h> +#include <linux/mfd/abx500.h> +#include <linux/mfd/ab8500/gpio.h> + +/* + * GPIO registers offset + * Bank: 0x10 + */ +#define AB8500_GPIO_SEL1_REG 0x00 +#define AB8500_GPIO_SEL2_REG 0x01 +#define AB8500_GPIO_SEL3_REG 0x02 +#define AB8500_GPIO_SEL4_REG 0x03 +#define AB8500_GPIO_SEL5_REG 0x04 +#define AB8500_GPIO_SEL6_REG 0x05 + +#define AB8500_GPIO_DIR1_REG 0x10 +#define AB8500_GPIO_DIR2_REG 0x11 +#define AB8500_GPIO_DIR3_REG 0x12 +#define AB8500_GPIO_DIR4_REG 0x13 +#define AB8500_GPIO_DIR5_REG 0x14 +#define AB8500_GPIO_DIR6_REG 0x15 + +#define AB8500_GPIO_OUT1_REG 0x20 +#define AB8500_GPIO_OUT2_REG 0x21 +#define AB8500_GPIO_OUT3_REG 0x22 +#define AB8500_GPIO_OUT4_REG 0x23 +#define AB8500_GPIO_OUT5_REG 0x24 +#define AB8500_GPIO_OUT6_REG 0x25 + +#define AB8500_GPIO_PUD1_REG 0x30 +#define AB8500_GPIO_PUD2_REG 0x31 +#define AB8500_GPIO_PUD3_REG 0x32 +#define AB8500_GPIO_PUD4_REG 0x33 +#define AB8500_GPIO_PUD5_REG 0x34 +#define AB8500_GPIO_PUD6_REG 0x35 + +#define AB8500_GPIO_IN1_REG 0x40 +#define AB8500_GPIO_IN2_REG 0x41 +#define AB8500_GPIO_IN3_REG 0x42 +#define AB8500_GPIO_IN4_REG 0x43 +#define AB8500_GPIO_IN5_REG 0x44 +#define AB8500_GPIO_IN6_REG 0x45 +#define AB8500_GPIO_ALTFUN_REG 0x45 +#define ALTFUN_REG_INDEX 6 +#define AB8500_NUM_GPIO 42 +#define AB8500_NUM_VIR_GPIO_IRQ 16 + +enum ab8500_gpio_action { + NONE, + STARTUP, + SHUTDOWN, + MASK, + UNMASK +}; + +struct ab8500_gpio { + struct gpio_chip chip; + struct ab8500 *parent; + struct device *dev; + struct mutex lock; + u32 irq_base; + enum ab8500_gpio_action irq_action; + u16 rising; + u16 falling; +}; +/** + * to_ab8500_gpio() - get the pointer to ab8500_gpio + * @chip: Member of the structure ab8500_gpio + */ +static inline struct ab8500_gpio *to_ab8500_gpio(struct gpio_chip *chip) +{ + return container_of(chip, struct ab8500_gpio, chip); +} + +static int ab8500_gpio_set_bits(struct gpio_chip *chip, u8 reg, + unsigned offset, int val) +{ + struct ab8500_gpio *ab8500_gpio = to_ab8500_gpio(chip); + u8 pos = offset % 8; + int ret; + + reg = reg + (offset / 8); + ret = abx500_mask_and_set_register_interruptible(ab8500_gpio->dev, + AB8500_MISC, reg, 1 << pos, val << pos); + if (ret < 0) + dev_err(ab8500_gpio->dev, "%s write failed\n", __func__); + return ret; +} +/** + * ab8500_gpio_get() - Get the particular GPIO value + * @chip: Gpio device + * @offset: GPIO number to read + */ +static int ab8500_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct ab8500_gpio *ab8500_gpio = to_ab8500_gpio(chip); + u8 mask = 1 << (offset % 8); + u8 reg = AB8500_GPIO_OUT1_REG + (offset / 8); + int ret; + u8 data; + ret = abx500_get_register_interruptible(ab8500_gpio->dev, AB8500_MISC, + reg, &data); + if (ret < 0) { + dev_err(ab8500_gpio->dev, "%s read failed\n", __func__); + return ret; + } + return (data & mask) >> (offset % 8); +} + +static void ab8500_gpio_set(struct gpio_chip *chip, unsigned offset, int val) +{ + struct ab8500_gpio *ab8500_gpio = to_ab8500_gpio(chip); + int ret; + /* Write the data */ + ret = ab8500_gpio_set_bits(chip, AB8500_GPIO_OUT1_REG, offset, 1); + if (ret < 0) + dev_err(ab8500_gpio->dev, "%s write failed\n", __func__); +} + +static int ab8500_gpio_direction_output(struct gpio_chip *chip, unsigned offset, + int val) +{ + int ret; + /* set direction as output */ + ret = ab8500_gpio_set_bits(chip, AB8500_GPIO_DIR1_REG, offset, 1); + if (ret < 0) + return ret; + /* disable pull down */ + ret = ab8500_gpio_set_bits(chip, AB8500_GPIO_PUD1_REG, offset, 1); + if (ret < 0) + return ret; + /* set the output as 1 or 0 */ + return ab8500_gpio_set_bits(chip, AB8500_GPIO_OUT1_REG, offset, val); + +} + +static int ab8500_gpio_direction_input(struct gpio_chip *chip, unsigned offset) +{ + /* set the register as input */ + return ab8500_gpio_set_bits(chip, AB8500_GPIO_DIR1_REG, offset, 0); +} + +static int ab8500_gpio_to_irq(struct gpio_chip *chip, unsigned offset) +{ + /* + * Only some GPIOs are interrupt capable, and they are + * organized in discontiguous clusters: + * + * GPIO6 to GPIO13 + * GPIO24 and GPIO25 + * GPIO36 to GPIO41 + */ + static struct ab8500_gpio_irq_cluster { + int start; + int end; + } clusters[] = { + {.start = 6, .end = 13}, + {.start = 24, .end = 25}, + {.start = 36, .end = 41}, + }; + struct ab8500_gpio *ab8500_gpio = to_ab8500_gpio(chip); + int base = ab8500_gpio->irq_base; + int i; + + for (i = 0; i < ARRAY_SIZE(clusters); i++) { + struct ab8500_gpio_irq_cluster *cluster = &clusters[i]; + + if (offset >= cluster->start && offset <= cluster->end) + return base + offset - cluster->start; + + /* Advance by the number of gpios in this cluster */ + base += cluster->end - cluster->start + 1; + } + + return -EINVAL; +} + +static struct gpio_chip ab8500gpio_chip = { + .label = "ab8500_gpio", + .owner = THIS_MODULE, + .direction_input = ab8500_gpio_direction_input, + .get = ab8500_gpio_get, + .direction_output = ab8500_gpio_direction_output, + .set = ab8500_gpio_set, + .to_irq = ab8500_gpio_to_irq, +}; + +static unsigned int irq_to_rising(unsigned int irq) +{ + struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq); + int offset = irq - ab8500_gpio->irq_base; + int new_irq = offset + AB8500_INT_GPIO6R + + ab8500_gpio->parent->irq_base; + return new_irq; +} + +static unsigned int irq_to_falling(unsigned int irq) +{ + struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq); + int offset = irq - ab8500_gpio->irq_base; + int new_irq = offset + AB8500_INT_GPIO6F + + ab8500_gpio->parent->irq_base; + return new_irq; + +} + +static unsigned int rising_to_irq(unsigned int irq, void *dev) +{ + struct ab8500_gpio *ab8500_gpio = dev; + int offset = irq - AB8500_INT_GPIO6R + - ab8500_gpio->parent->irq_base ; + int new_irq = offset + ab8500_gpio->irq_base; + return new_irq; +} + +static unsigned int falling_to_irq(unsigned int irq, void *dev) +{ + struct ab8500_gpio *ab8500_gpio = dev; + int offset = irq - AB8500_INT_GPIO6F + - ab8500_gpio->parent->irq_base ; + int new_irq = offset + ab8500_gpio->irq_base; + return new_irq; + +} + +/* + * IRQ handler + */ + +static irqreturn_t handle_rising(int irq, void *dev) +{ + + handle_nested_irq(rising_to_irq(irq , dev)); + return IRQ_HANDLED; +} + +static irqreturn_t handle_falling(int irq, void *dev) +{ + + handle_nested_irq(falling_to_irq(irq, dev)); + return IRQ_HANDLED; +} + +static void ab8500_gpio_irq_lock(unsigned int irq) +{ + struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq); + mutex_lock(&ab8500_gpio->lock); +} + +static void ab8500_gpio_irq_sync_unlock(unsigned int irq) +{ + struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq); + int offset = irq - ab8500_gpio->irq_base; + bool rising = ab8500_gpio->rising & BIT(offset); + bool falling = ab8500_gpio->falling & BIT(offset); + int ret; + + switch (ab8500_gpio->irq_action) { + case STARTUP: + if (rising) + ret = request_threaded_irq(irq_to_rising(irq), + NULL, handle_rising, + IRQF_TRIGGER_RISING, + "ab8500-gpio-r", ab8500_gpio); + if (falling) + ret = request_threaded_irq(irq_to_falling(irq), + NULL, handle_falling, + IRQF_TRIGGER_FALLING, + "ab8500-gpio-f", ab8500_gpio); + break; + case SHUTDOWN: + if (rising) + free_irq(irq_to_rising(irq), ab8500_gpio); + if (falling) + free_irq(irq_to_falling(irq), ab8500_gpio); + break; + case MASK: + if (rising) + disable_irq(irq_to_rising(irq)); + if (falling) + disable_irq(irq_to_falling(irq)); + break; + case UNMASK: + if (rising) + enable_irq(irq_to_rising(irq)); + if (falling) + enable_irq(irq_to_falling(irq)); + break; + case NONE: + break; + } + ab8500_gpio->irq_action = NONE; + ab8500_gpio->rising &= ~(BIT(offset)); + ab8500_gpio->falling &= ~(BIT(offset)); + mutex_unlock(&ab8500_gpio->lock); +} + + +static void ab8500_gpio_irq_mask(unsigned int irq) +{ + struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq); + ab8500_gpio->irq_action = MASK; +} + +static void ab8500_gpio_irq_unmask(unsigned int irq) +{ + struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq); + ab8500_gpio->irq_action = UNMASK; +} + +static int ab8500_gpio_irq_set_type(unsigned int irq, unsigned int type) +{ + struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq); + int offset = irq - ab8500_gpio->irq_base; + + if (type == IRQ_TYPE_EDGE_BOTH) { + ab8500_gpio->rising = BIT(offset); + ab8500_gpio->falling = BIT(offset); + } else if (type == IRQ_TYPE_EDGE_RISING) { + ab8500_gpio->rising = BIT(offset); + } else { + ab8500_gpio->falling = BIT(offset); + } + return 0; +} + +unsigned int ab8500_gpio_irq_startup(unsigned int irq) +{ + struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq); + ab8500_gpio->irq_action = STARTUP; + return 0; +} + +void ab8500_gpio_irq_shutdown(unsigned int irq) +{ + struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq); + ab8500_gpio->irq_action = SHUTDOWN; +} + +static struct irq_chip ab8500_gpio_irq_chip = { + .name = "ab8500-gpio", + .startup = ab8500_gpio_irq_startup, + .shutdown = ab8500_gpio_irq_shutdown, + .bus_lock = ab8500_gpio_irq_lock, + .bus_sync_unlock = ab8500_gpio_irq_sync_unlock, + .mask = ab8500_gpio_irq_mask, + .unmask = ab8500_gpio_irq_unmask, + .set_type = ab8500_gpio_irq_set_type, +}; + +static int ab8500_gpio_irq_init(struct ab8500_gpio *ab8500_gpio) +{ + u32 base = ab8500_gpio->irq_base; + int irq; + + for (irq = base; irq < base + AB8500_NUM_VIR_GPIO_IRQ ; irq++) { + set_irq_chip_data(irq, ab8500_gpio); + set_irq_chip_and_handler(irq, &ab8500_gpio_irq_chip, + handle_simple_irq); + set_irq_nested_thread(irq, 1); +#ifdef CONFIG_ARM + set_irq_flags(irq, IRQF_VALID); +#else + set_irq_noprobe(irq); +#endif + } + + return 0; +} + +static void ab8500_gpio_irq_remove(struct ab8500_gpio *ab8500_gpio) +{ + int base = ab8500_gpio->irq_base; + int irq; + + for (irq = base; irq < base + AB8500_NUM_VIR_GPIO_IRQ; irq++) { +#ifdef CONFIG_ARM + set_irq_flags(irq, 0); +#endif + set_irq_chip_and_handler(irq, NULL, NULL); + set_irq_chip_data(irq, NULL); + } +} + +static int __devinit ab8500_gpio_probe(struct platform_device *pdev) +{ + struct ab8500_platform_data *ab8500_pdata = + dev_get_platdata(pdev->dev.parent); + struct ab8500_gpio_platform_data *pdata; + struct ab8500_gpio *ab8500_gpio; + int ret; + int i; + + pdata = ab8500_pdata->gpio; + if (!pdata) { + dev_err(&pdev->dev, "gpio platform data missing\n"); + return -ENODEV; + } + + ab8500_gpio = kzalloc(sizeof(struct ab8500_gpio), GFP_KERNEL); + if (ab8500_gpio == NULL) { + dev_err(&pdev->dev, "failed to allocate memory\n"); + return -ENOMEM; + } + ab8500_gpio->dev = &pdev->dev; + ab8500_gpio->parent = dev_get_drvdata(pdev->dev.parent); + ab8500_gpio->chip = ab8500gpio_chip; + ab8500_gpio->chip.ngpio = AB8500_NUM_GPIO; + ab8500_gpio->chip.dev = &pdev->dev; + ab8500_gpio->chip.base = pdata->gpio_base; + ab8500_gpio->irq_base = pdata->irq_base; + /* initialize the lock */ + mutex_init(&ab8500_gpio->lock); + /* + * AB8500 core will handle and clear the IRQ + * configre GPIO based on config-reg value. + * These values are for selecting the PINs as + * GPIO or alternate function + */ + for (i = AB8500_GPIO_SEL1_REG; i <= AB8500_GPIO_SEL6_REG; i++) { + ret = abx500_set_register_interruptible(ab8500_gpio->dev, + AB8500_MISC, i, + pdata->config_reg[i]); + if (ret < 0) + goto out_free; + } + ret = abx500_set_register_interruptible(ab8500_gpio->dev, AB8500_MISC, + AB8500_GPIO_ALTFUN_REG, + pdata->config_reg[ALTFUN_REG_INDEX]); + if (ret < 0) + goto out_free; + + ret = ab8500_gpio_irq_init(ab8500_gpio); + if (ret) + goto out_free; + ret = gpiochip_add(&ab8500_gpio->chip); + if (ret) { + dev_err(&pdev->dev, "unable to add gpiochip: %d\n", + ret); + goto out_rem_irq; + } + platform_set_drvdata(pdev, ab8500_gpio); + return 0; + +out_rem_irq: + ab8500_gpio_irq_remove(ab8500_gpio); +out_free: + mutex_destroy(&ab8500_gpio->lock); + kfree(ab8500_gpio); + return ret; +} + +/* + * ab8500_gpio_remove() - remove Ab8500-gpio driver + * @pdev : Platform device registered + */ +static int __devexit ab8500_gpio_remove(struct platform_device *pdev) +{ + struct ab8500_gpio *ab8500_gpio = platform_get_drvdata(pdev); + int ret; + + ret = gpiochip_remove(&ab8500_gpio->chip); + if (ret < 0) { + dev_err(ab8500_gpio->dev, "unable to remove gpiochip:\ + %d\n", ret); + return ret; + } + + platform_set_drvdata(pdev, NULL); + mutex_destroy(&ab8500_gpio->lock); + kfree(ab8500_gpio); + + return 0; +} + +static struct platform_driver ab8500_gpio_driver = { + .driver = { + .name = "ab8500-gpio", + .owner = THIS_MODULE, + }, + .probe = ab8500_gpio_probe, + .remove = __devexit_p(ab8500_gpio_remove), +}; + +static int __init ab8500_gpio_init(void) +{ + return platform_driver_register(&ab8500_gpio_driver); +} +arch_initcall(ab8500_gpio_init); + +static void __exit ab8500_gpio_exit(void) +{ + platform_driver_unregister(&ab8500_gpio_driver); +} +module_exit(ab8500_gpio_exit); + +MODULE_AUTHOR("BIBEK BASU <bibek.basu@stericsson.com>"); +MODULE_DESCRIPTION("Driver allows to use AB8500 unused pins\ + to be used as GPIO"); +MODULE_ALIAS("AB8500 GPIO driver"); +MODULE_LICENSE("GPL v2"); |