/* * Copyright (C) ST-Ericsson SA 2010 * * License Terms: GNU General Public License, version 2 * Author: Rabin Vincent for ST-Ericsson */ #include #include #include #include #include #include #include #include #include /* * 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 /* No variant has more than 24 GPIOs */ #define CACHE_NR_BANKS (24 / 8) struct stmpe_gpio { struct gpio_chip chip; struct stmpe *stmpe; struct device *dev; struct mutex irq_lock; u32 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); /* * Some variants have single register for gpio set/clear functionality. * For them we need to write 0 to clear and 1 to set. */ if (stmpe->regs[STMPE_IDX_GPSR_LSB] == stmpe->regs[STMPE_IDX_GPCR_LSB]) stmpe_set_bits(stmpe, reg, mask, val ? mask : 0); else 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_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, .request = stmpe_gpio_request, .can_sleep = true, }; static int stmpe_gpio_irq_set_type(struct irq_data *d, unsigned int type) { struct gpio_chip *gc = irq_data_get_irq_chip_data(d); struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc); int offset = d->hwirq; int regoffset = offset / 8; int mask = 1 << (offset % 8); if (type & IRQ_TYPE_LEVEL_LOW || type & IRQ_TYPE_LEVEL_HIGH) return -EINVAL; /* STMPE801 doesn't have RE and FE registers */ if (stmpe_gpio->stmpe->partnum == STMPE801) return 0; 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 gpio_chip *gc = irq_data_get_irq_chip_data(d); struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc); mutex_lock(&stmpe_gpio->irq_lock); } static void stmpe_gpio_irq_sync_unlock(struct irq_data *d) { struct gpio_chip *gc = irq_data_get_irq_chip_data(d); struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc); 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++) { /* STMPE801 doesn't have RE and FE registers */ if ((stmpe->partnum == STMPE801) && (i != REG_IE)) continue; 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 gpio_chip *gc = irq_data_get_irq_chip_data(d); struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc); int offset = d->hwirq; 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 gpio_chip *gc = irq_data_get_irq_chip_data(d); struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc); int offset = d->hwirq; int regoffset = offset / 8; int mask = 1 << (offset % 8); stmpe_gpio->regs[REG_IE][regoffset] |= mask; } static void stmpe_dbg_show_one(struct seq_file *s, struct gpio_chip *gc, unsigned offset, unsigned gpio) { struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc); struct stmpe *stmpe = stmpe_gpio->stmpe; const char *label = gpiochip_is_requested(gc, offset); int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8); bool val = !!stmpe_gpio_get(gc, offset); u8 dir_reg = stmpe->regs[STMPE_IDX_GPDR_LSB] - (offset / 8); u8 mask = 1 << (offset % 8); int ret; u8 dir; ret = stmpe_reg_read(stmpe, dir_reg); if (ret < 0) return; dir = !!(ret & mask); if (dir) { seq_printf(s, " gpio-%-3d (%-20.20s) out %s", gpio, label ?: "(none)", val ? "hi" : "lo"); } else { u8 edge_det_reg = stmpe->regs[STMPE_IDX_GPEDR_MSB] + num_banks - 1 - (offset / 8); u8 rise_reg = stmpe->regs[STMPE_IDX_GPRER_LSB] - (offset / 8); u8 fall_reg = stmpe->regs[STMPE_IDX_GPFER_LSB] - (offset / 8); u8 irqen_reg = stmpe->regs[STMPE_IDX_IEGPIOR_LSB] - (offset / 8); bool edge_det; bool rise; bool fall; bool irqen; ret = stmpe_reg_read(stmpe, edge_det_reg); if (ret < 0) return; edge_det = !!(ret & mask); ret = stmpe_reg_read(stmpe, rise_reg); if (ret < 0) return; rise = !!(ret & mask); ret = stmpe_reg_read(stmpe, fall_reg); if (ret < 0) return; fall = !!(ret & mask); ret = stmpe_reg_read(stmpe, irqen_reg); if (ret < 0) return; irqen = !!(ret & mask); seq_printf(s, " gpio-%-3d (%-20.20s) in %s %s %s%s%s", gpio, label ?: "(none)", val ? "hi" : "lo", edge_det ? "edge-asserted" : "edge-inactive", irqen ? "IRQ-enabled" : "", rise ? " rising-edge-detection" : "", fall ? " falling-edge-detection" : ""); } } static void stmpe_dbg_show(struct seq_file *s, struct gpio_chip *gc) { unsigned i; unsigned gpio = gc->base; for (i = 0; i < gc->ngpio; i++, gpio++) { stmpe_dbg_show_one(s, gc, i, gpio); seq_printf(s, "\n"); } } 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; int child_irq = irq_find_mapping(stmpe_gpio->chip.irqdomain, line); handle_nested_irq(child_irq); stat &= ~(1 << bit); } stmpe_reg_write(stmpe, statmsbreg + i, status[i]); /* Edge detect register is not present on 801 */ if (stmpe->partnum != STMPE801) stmpe_reg_write(stmpe, stmpe->regs[STMPE_IDX_GPEDR_MSB] + i, status[i]); } return IRQ_HANDLED; } static int stmpe_gpio_probe(struct platform_device *pdev) { struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent); struct device_node *np = pdev->dev.of_node; struct stmpe_gpio *stmpe_gpio; int ret; int irq = 0; irq = platform_get_irq(pdev, 0); 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.of_node = np; stmpe_gpio->chip.base = -1; if (IS_ENABLED(CONFIG_DEBUG_FS)) stmpe_gpio->chip.dbg_show = stmpe_dbg_show; of_property_read_u32(np, "st,norequest-mask", &stmpe_gpio->norequest_mask); if (irq < 0) dev_info(&pdev->dev, "device configured in no-irq mode: " "irqs are not available\n"); ret = stmpe_enable(stmpe, STMPE_BLOCK_GPIO); if (ret) goto out_free; ret = gpiochip_add(&stmpe_gpio->chip); if (ret) { dev_err(&pdev->dev, "unable to add gpiochip: %d\n", ret); goto out_disable; } if (irq > 0) { ret = devm_request_threaded_irq(&pdev->dev, 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_disable; } ret = gpiochip_irqchip_add(&stmpe_gpio->chip, &stmpe_gpio_irq_chip, 0, handle_simple_irq, IRQ_TYPE_NONE); if (ret) { dev_err(&pdev->dev, "could not connect irqchip to gpiochip\n"); goto out_disable; } gpiochip_set_chained_irqchip(&stmpe_gpio->chip, &stmpe_gpio_irq_chip, irq, NULL); } platform_set_drvdata(pdev, stmpe_gpio); return 0; out_disable: stmpe_disable(stmpe, STMPE_BLOCK_GPIO); gpiochip_remove(&stmpe_gpio->chip); out_free: kfree(stmpe_gpio); return ret; } static int stmpe_gpio_remove(struct platform_device *pdev) { struct stmpe_gpio *stmpe_gpio = platform_get_drvdata(pdev); struct stmpe *stmpe = stmpe_gpio->stmpe; gpiochip_remove(&stmpe_gpio->chip); stmpe_disable(stmpe, STMPE_BLOCK_GPIO); 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 = 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 ");