diff options
author | Chris Metcalf <cmetcalf@tilera.com> | 2010-08-13 19:59:15 -0400 |
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committer | Chris Metcalf <cmetcalf@tilera.com> | 2010-08-13 19:59:15 -0400 |
commit | 7d72e6fa56c4100b9669efe0044f77ed9eb785a1 (patch) | |
tree | 5e90bf4969809a1ab20b97432b85be20ccfaa1f4 /drivers/gpio/stmpe-gpio.c | |
parent | ba00376b0b13f234d839541a7b36a5bf5c2a4036 (diff) | |
parent | 2be1f3a73dd02e38e181cf5abacb3d45a6a2d6b8 (diff) |
Merge branch 'master' into for-linus
Diffstat (limited to 'drivers/gpio/stmpe-gpio.c')
-rw-r--r-- | drivers/gpio/stmpe-gpio.c | 399 |
1 files changed, 399 insertions, 0 deletions
diff --git a/drivers/gpio/stmpe-gpio.c b/drivers/gpio/stmpe-gpio.c new file mode 100644 index 00000000000..4e1f1b9d5e6 --- /dev/null +++ b/drivers/gpio/stmpe-gpio.c @@ -0,0 +1,399 @@ +/* + * Copyright (C) ST-Ericsson SA 2010 + * + * License Terms: GNU General Public License, version 2 + * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson + */ + +#include <linux/module.h> +#include <linux/init.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/stmpe.h> + +/* + * These registers are modified under the irq bus lock and cached to avoid + * unnecessary writes in bus_sync_unlock. + */ +enum { REG_RE, REG_FE, REG_IE }; + +#define CACHE_NR_REGS 3 +#define CACHE_NR_BANKS (STMPE_NR_GPIOS / 8) + +struct stmpe_gpio { + struct gpio_chip chip; + struct stmpe *stmpe; + struct device *dev; + struct mutex irq_lock; + + int irq_base; + + /* Caches of interrupt control registers for bus_lock */ + u8 regs[CACHE_NR_REGS][CACHE_NR_BANKS]; + u8 oldregs[CACHE_NR_REGS][CACHE_NR_BANKS]; +}; + +static inline struct stmpe_gpio *to_stmpe_gpio(struct gpio_chip *chip) +{ + return container_of(chip, struct stmpe_gpio, chip); +} + +static int stmpe_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip); + struct stmpe *stmpe = stmpe_gpio->stmpe; + u8 reg = stmpe->regs[STMPE_IDX_GPMR_LSB] - (offset / 8); + u8 mask = 1 << (offset % 8); + int ret; + + ret = stmpe_reg_read(stmpe, reg); + if (ret < 0) + return ret; + + return ret & mask; +} + +static void stmpe_gpio_set(struct gpio_chip *chip, unsigned offset, int val) +{ + struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip); + struct stmpe *stmpe = stmpe_gpio->stmpe; + int which = val ? STMPE_IDX_GPSR_LSB : STMPE_IDX_GPCR_LSB; + u8 reg = stmpe->regs[which] - (offset / 8); + u8 mask = 1 << (offset % 8); + + stmpe_reg_write(stmpe, reg, mask); +} + +static int stmpe_gpio_direction_output(struct gpio_chip *chip, + unsigned offset, int val) +{ + struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip); + struct stmpe *stmpe = stmpe_gpio->stmpe; + u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB] - (offset / 8); + u8 mask = 1 << (offset % 8); + + stmpe_gpio_set(chip, offset, val); + + return stmpe_set_bits(stmpe, reg, mask, mask); +} + +static int stmpe_gpio_direction_input(struct gpio_chip *chip, + unsigned offset) +{ + struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip); + struct stmpe *stmpe = stmpe_gpio->stmpe; + u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB] - (offset / 8); + u8 mask = 1 << (offset % 8); + + return stmpe_set_bits(stmpe, reg, mask, 0); +} + +static int stmpe_gpio_to_irq(struct gpio_chip *chip, unsigned offset) +{ + struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip); + + return stmpe_gpio->irq_base + offset; +} + +static int stmpe_gpio_request(struct gpio_chip *chip, unsigned offset) +{ + struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip); + struct stmpe *stmpe = stmpe_gpio->stmpe; + + return stmpe_set_altfunc(stmpe, 1 << offset, STMPE_BLOCK_GPIO); +} + +static struct gpio_chip template_chip = { + .label = "stmpe", + .owner = THIS_MODULE, + .direction_input = stmpe_gpio_direction_input, + .get = stmpe_gpio_get, + .direction_output = stmpe_gpio_direction_output, + .set = stmpe_gpio_set, + .to_irq = stmpe_gpio_to_irq, + .request = stmpe_gpio_request, + .can_sleep = 1, +}; + +static int stmpe_gpio_irq_set_type(unsigned int irq, unsigned int type) +{ + struct stmpe_gpio *stmpe_gpio = get_irq_chip_data(irq); + int offset = irq - stmpe_gpio->irq_base; + int regoffset = offset / 8; + int mask = 1 << (offset % 8); + + if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_LEVEL_HIGH) + return -EINVAL; + + if (type == IRQ_TYPE_EDGE_RISING) + stmpe_gpio->regs[REG_RE][regoffset] |= mask; + else + stmpe_gpio->regs[REG_RE][regoffset] &= ~mask; + + if (type == IRQ_TYPE_EDGE_FALLING) + stmpe_gpio->regs[REG_FE][regoffset] |= mask; + else + stmpe_gpio->regs[REG_FE][regoffset] &= ~mask; + + return 0; +} + +static void stmpe_gpio_irq_lock(unsigned int irq) +{ + struct stmpe_gpio *stmpe_gpio = get_irq_chip_data(irq); + + mutex_lock(&stmpe_gpio->irq_lock); +} + +static void stmpe_gpio_irq_sync_unlock(unsigned int irq) +{ + struct stmpe_gpio *stmpe_gpio = get_irq_chip_data(irq); + struct stmpe *stmpe = stmpe_gpio->stmpe; + int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8); + static const u8 regmap[] = { + [REG_RE] = STMPE_IDX_GPRER_LSB, + [REG_FE] = STMPE_IDX_GPFER_LSB, + [REG_IE] = STMPE_IDX_IEGPIOR_LSB, + }; + int i, j; + + for (i = 0; i < CACHE_NR_REGS; i++) { + for (j = 0; j < num_banks; j++) { + u8 old = stmpe_gpio->oldregs[i][j]; + u8 new = stmpe_gpio->regs[i][j]; + + if (new == old) + continue; + + stmpe_gpio->oldregs[i][j] = new; + stmpe_reg_write(stmpe, stmpe->regs[regmap[i]] - j, new); + } + } + + mutex_unlock(&stmpe_gpio->irq_lock); +} + +static void stmpe_gpio_irq_mask(unsigned int irq) +{ + struct stmpe_gpio *stmpe_gpio = get_irq_chip_data(irq); + int offset = irq - stmpe_gpio->irq_base; + int regoffset = offset / 8; + int mask = 1 << (offset % 8); + + stmpe_gpio->regs[REG_IE][regoffset] &= ~mask; +} + +static void stmpe_gpio_irq_unmask(unsigned int irq) +{ + struct stmpe_gpio *stmpe_gpio = get_irq_chip_data(irq); + int offset = irq - stmpe_gpio->irq_base; + int regoffset = offset / 8; + int mask = 1 << (offset % 8); + + stmpe_gpio->regs[REG_IE][regoffset] |= mask; +} + +static struct irq_chip stmpe_gpio_irq_chip = { + .name = "stmpe-gpio", + .bus_lock = stmpe_gpio_irq_lock, + .bus_sync_unlock = stmpe_gpio_irq_sync_unlock, + .mask = stmpe_gpio_irq_mask, + .unmask = stmpe_gpio_irq_unmask, + .set_type = stmpe_gpio_irq_set_type, +}; + +static irqreturn_t stmpe_gpio_irq(int irq, void *dev) +{ + struct stmpe_gpio *stmpe_gpio = dev; + struct stmpe *stmpe = stmpe_gpio->stmpe; + u8 statmsbreg = stmpe->regs[STMPE_IDX_ISGPIOR_MSB]; + int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8); + u8 status[num_banks]; + int ret; + int i; + + ret = stmpe_block_read(stmpe, statmsbreg, num_banks, status); + if (ret < 0) + return IRQ_NONE; + + for (i = 0; i < num_banks; i++) { + int bank = num_banks - i - 1; + unsigned int enabled = stmpe_gpio->regs[REG_IE][bank]; + unsigned int stat = status[i]; + + stat &= enabled; + if (!stat) + continue; + + while (stat) { + int bit = __ffs(stat); + int line = bank * 8 + bit; + + handle_nested_irq(stmpe_gpio->irq_base + line); + stat &= ~(1 << bit); + } + + stmpe_reg_write(stmpe, statmsbreg + i, status[i]); + stmpe_reg_write(stmpe, stmpe->regs[STMPE_IDX_GPEDR_MSB] + i, + status[i]); + } + + return IRQ_HANDLED; +} + +static int __devinit stmpe_gpio_irq_init(struct stmpe_gpio *stmpe_gpio) +{ + int base = stmpe_gpio->irq_base; + int irq; + + for (irq = base; irq < base + stmpe_gpio->chip.ngpio; irq++) { + set_irq_chip_data(irq, stmpe_gpio); + set_irq_chip_and_handler(irq, &stmpe_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 stmpe_gpio_irq_remove(struct stmpe_gpio *stmpe_gpio) +{ + int base = stmpe_gpio->irq_base; + int irq; + + for (irq = base; irq < base + stmpe_gpio->chip.ngpio; 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 stmpe_gpio_probe(struct platform_device *pdev) +{ + struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent); + struct stmpe_gpio_platform_data *pdata; + struct stmpe_gpio *stmpe_gpio; + int ret; + int irq; + + pdata = stmpe->pdata->gpio; + if (!pdata) + return -ENODEV; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + stmpe_gpio = kzalloc(sizeof(struct stmpe_gpio), GFP_KERNEL); + if (!stmpe_gpio) + return -ENOMEM; + + mutex_init(&stmpe_gpio->irq_lock); + + stmpe_gpio->dev = &pdev->dev; + stmpe_gpio->stmpe = stmpe; + + stmpe_gpio->chip = template_chip; + stmpe_gpio->chip.ngpio = stmpe->num_gpios; + stmpe_gpio->chip.dev = &pdev->dev; + stmpe_gpio->chip.base = pdata ? pdata->gpio_base : -1; + + stmpe_gpio->irq_base = stmpe->irq_base + STMPE_INT_GPIO(0); + + ret = stmpe_enable(stmpe, STMPE_BLOCK_GPIO); + if (ret) + return ret; + + ret = stmpe_gpio_irq_init(stmpe_gpio); + if (ret) + goto out_free; + + ret = request_threaded_irq(irq, NULL, stmpe_gpio_irq, IRQF_ONESHOT, + "stmpe-gpio", stmpe_gpio); + if (ret) { + dev_err(&pdev->dev, "unable to get irq: %d\n", ret); + goto out_removeirq; + } + + ret = gpiochip_add(&stmpe_gpio->chip); + if (ret) { + dev_err(&pdev->dev, "unable to add gpiochip: %d\n", ret); + goto out_freeirq; + } + + if (pdata && pdata->setup) + pdata->setup(stmpe, stmpe_gpio->chip.base); + + platform_set_drvdata(pdev, stmpe_gpio); + + return 0; + +out_freeirq: + free_irq(irq, stmpe_gpio); +out_removeirq: + stmpe_gpio_irq_remove(stmpe_gpio); +out_free: + kfree(stmpe_gpio); + return ret; +} + +static int __devexit stmpe_gpio_remove(struct platform_device *pdev) +{ + struct stmpe_gpio *stmpe_gpio = platform_get_drvdata(pdev); + struct stmpe *stmpe = stmpe_gpio->stmpe; + struct stmpe_gpio_platform_data *pdata = stmpe->pdata->gpio; + int irq = platform_get_irq(pdev, 0); + int ret; + + if (pdata && pdata->remove) + pdata->remove(stmpe, stmpe_gpio->chip.base); + + ret = gpiochip_remove(&stmpe_gpio->chip); + if (ret < 0) { + dev_err(stmpe_gpio->dev, + "unable to remove gpiochip: %d\n", ret); + return ret; + } + + stmpe_disable(stmpe, STMPE_BLOCK_GPIO); + + free_irq(irq, stmpe_gpio); + stmpe_gpio_irq_remove(stmpe_gpio); + platform_set_drvdata(pdev, NULL); + kfree(stmpe_gpio); + + return 0; +} + +static struct platform_driver stmpe_gpio_driver = { + .driver.name = "stmpe-gpio", + .driver.owner = THIS_MODULE, + .probe = stmpe_gpio_probe, + .remove = __devexit_p(stmpe_gpio_remove), +}; + +static int __init stmpe_gpio_init(void) +{ + return platform_driver_register(&stmpe_gpio_driver); +} +subsys_initcall(stmpe_gpio_init); + +static void __exit stmpe_gpio_exit(void) +{ + platform_driver_unregister(&stmpe_gpio_driver); +} +module_exit(stmpe_gpio_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("STMPExxxx GPIO driver"); +MODULE_AUTHOR("Rabin Vincent <rabin.vincent@stericsson.com>"); |