/* * 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; unsigned norequest_mask; /* 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; if (stmpe_gpio->norequest_mask & (1 << offset)) return -EINVAL; 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(struct irq_data *d, unsigned int type) { struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d); int offset = d->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(struct irq_data *d) { struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d); mutex_lock(&stmpe_gpio->irq_lock); } static void stmpe_gpio_irq_sync_unlock(struct irq_data *d) { struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d); 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(struct irq_data *d) { struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d); int offset = d->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(struct irq_data *d) { struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d); int offset = d->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", .irq_bus_lock = stmpe_gpio_irq_lock, .irq_bus_sync_unlock = stmpe_gpio_irq_sync_unlock, .irq_mask = stmpe_gpio_irq_mask, .irq_unmask = stmpe_gpio_irq_unmask, .irq_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; 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->norequest_mask = pdata ? pdata->norequest_mask : 0; 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) goto out_free; ret = stmpe_gpio_irq_init(stmpe_gpio); if (ret) goto out_disable; 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_disable: stmpe_disable(stmpe, STMPE_BLOCK_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>");