// SPDX-License-Identifier: GPL-2.0-only /* * Support functions for OMAP GPIO * * Copyright (C) 2003-2005 Nokia Corporation * Written by Juha Yrjölä <juha.yrjola@nokia.com> * * Copyright (C) 2009 Texas Instruments * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com> */ #include <linux/init.h> #include <linux/module.h> #include <linux/interrupt.h> #include <linux/seq_file.h> #include <linux/syscore_ops.h> #include <linux/err.h> #include <linux/clk.h> #include <linux/io.h> #include <linux/cpu_pm.h> #include <linux/device.h> #include <linux/pm_runtime.h> #include <linux/pm.h> #include <linux/of.h> #include <linux/gpio/driver.h> #include <linux/bitops.h> #include <linux/platform_data/gpio-omap.h> #define OMAP4_GPIO_DEBOUNCINGTIME_MASK 0xFF struct gpio_regs { u32 sysconfig; u32 irqenable1; u32 irqenable2; u32 wake_en; u32 ctrl; u32 oe; u32 leveldetect0; u32 leveldetect1; u32 risingdetect; u32 fallingdetect; u32 dataout; u32 debounce; u32 debounce_en; }; struct gpio_bank { void __iomem *base; const struct omap_gpio_reg_offs *regs; struct device *dev; int irq; u32 non_wakeup_gpios; u32 enabled_non_wakeup_gpios; struct gpio_regs context; u32 saved_datain; u32 level_mask; u32 toggle_mask; raw_spinlock_t lock; raw_spinlock_t wa_lock; struct gpio_chip chip; struct clk *dbck; struct notifier_block nb; unsigned int is_suspended:1; unsigned int needs_resume:1; u32 mod_usage; u32 irq_usage; u32 dbck_enable_mask; bool dbck_enabled; bool is_mpuio; bool dbck_flag; bool loses_context; bool context_valid; int stride; u32 width; int context_loss_count; void (*set_dataout)(struct gpio_bank *bank, unsigned gpio, int enable); int (*get_context_loss_count)(struct device *dev); }; #define GPIO_MOD_CTRL_BIT BIT(0) #define BANK_USED(bank) (bank->mod_usage || bank->irq_usage) #define LINE_USED(line, offset) (line & (BIT(offset))) static void omap_gpio_unmask_irq(struct irq_data *d); static inline struct gpio_bank *omap_irq_data_get_bank(struct irq_data *d) { struct gpio_chip *chip = irq_data_get_irq_chip_data(d); return gpiochip_get_data(chip); } static inline u32 omap_gpio_rmw(void __iomem *reg, u32 mask, bool set) { u32 val = readl_relaxed(reg); if (set) val |= mask; else val &= ~mask; writel_relaxed(val, reg); return val; } static void omap_set_gpio_direction(struct gpio_bank *bank, int gpio, int is_input) { bank->context.oe = omap_gpio_rmw(bank->base + bank->regs->direction, BIT(gpio), is_input); } /* set data out value using dedicate set/clear register */ static void omap_set_gpio_dataout_reg(struct gpio_bank *bank, unsigned offset, int enable) { void __iomem *reg = bank->base; u32 l = BIT(offset); if (enable) { reg += bank->regs->set_dataout; bank->context.dataout |= l; } else { reg += bank->regs->clr_dataout; bank->context.dataout &= ~l; } writel_relaxed(l, reg); } /* set data out value using mask register */ static void omap_set_gpio_dataout_mask(struct gpio_bank *bank, unsigned offset, int enable) { bank->context.dataout = omap_gpio_rmw(bank->base + bank->regs->dataout, BIT(offset), enable); } static inline void omap_gpio_dbck_enable(struct gpio_bank *bank) { if (bank->dbck_enable_mask && !bank->dbck_enabled) { clk_enable(bank->dbck); bank->dbck_enabled = true; writel_relaxed(bank->dbck_enable_mask, bank->base + bank->regs->debounce_en); } } static inline void omap_gpio_dbck_disable(struct gpio_bank *bank) { if (bank->dbck_enable_mask && bank->dbck_enabled) { /* * Disable debounce before cutting it's clock. If debounce is * enabled but the clock is not, GPIO module seems to be unable * to detect events and generate interrupts at least on OMAP3. */ writel_relaxed(0, bank->base + bank->regs->debounce_en); clk_disable(bank->dbck); bank->dbck_enabled = false; } } /** * omap2_set_gpio_debounce - low level gpio debounce time * @bank: the gpio bank we're acting upon * @offset: the gpio number on this @bank * @debounce: debounce time to use * * OMAP's debounce time is in 31us steps * <debounce time> = (GPIO_DEBOUNCINGTIME[7:0].DEBOUNCETIME + 1) x 31 * so we need to convert and round up to the closest unit. * * Return: 0 on success, negative error otherwise. */ static int omap2_set_gpio_debounce(struct gpio_bank *bank, unsigned offset, unsigned debounce) { u32 val; u32 l; bool enable = !!debounce; if (!bank->dbck_flag) return -ENOTSUPP; if (enable) { debounce = DIV_ROUND_UP(debounce, 31) - 1; if ((debounce & OMAP4_GPIO_DEBOUNCINGTIME_MASK) != debounce) return -EINVAL; } l = BIT(offset); clk_enable(bank->dbck); writel_relaxed(debounce, bank->base + bank->regs->debounce); val = omap_gpio_rmw(bank->base + bank->regs->debounce_en, l, enable); bank->dbck_enable_mask = val; clk_disable(bank->dbck); /* * Enable debounce clock per module. * This call is mandatory because in omap_gpio_request() when * *_runtime_get_sync() is called, _gpio_dbck_enable() within * runtime callbck fails to turn on dbck because dbck_enable_mask * used within _gpio_dbck_enable() is still not initialized at * that point. Therefore we have to enable dbck here. */ omap_gpio_dbck_enable(bank); if (bank->dbck_enable_mask) { bank->context.debounce = debounce; bank->context.debounce_en = val; } return 0; } /** * omap_clear_gpio_debounce - clear debounce settings for a gpio * @bank: the gpio bank we're acting upon * @offset: the gpio number on this @bank * * If a gpio is using debounce, then clear the debounce enable bit and if * this is the only gpio in this bank using debounce, then clear the debounce * time too. The debounce clock will also be disabled when calling this function * if this is the only gpio in the bank using debounce. */ static void omap_clear_gpio_debounce(struct gpio_bank *bank, unsigned offset) { u32 gpio_bit = BIT(offset); if (!bank->dbck_flag) return; if (!(bank->dbck_enable_mask & gpio_bit)) return; bank->dbck_enable_mask &= ~gpio_bit; bank->context.debounce_en &= ~gpio_bit; writel_relaxed(bank->context.debounce_en, bank->base + bank->regs->debounce_en); if (!bank->dbck_enable_mask) { bank->context.debounce = 0; writel_relaxed(bank->context.debounce, bank->base + bank->regs->debounce); clk_disable(bank->dbck); bank->dbck_enabled = false; } } /* * Off mode wake-up capable GPIOs in bank(s) that are in the wakeup domain. * See TRM section for GPIO for "Wake-Up Generation" for the list of GPIOs * in wakeup domain. If bank->non_wakeup_gpios is not configured, assume none * are capable waking up the system from off mode. */ static bool omap_gpio_is_off_wakeup_capable(struct gpio_bank *bank, u32 gpio_mask) { u32 no_wake = bank->non_wakeup_gpios; if (no_wake) return !!(~no_wake & gpio_mask); return false; } static inline void omap_set_gpio_trigger(struct gpio_bank *bank, int gpio, unsigned trigger) { void __iomem *base = bank->base; u32 gpio_bit = BIT(gpio); omap_gpio_rmw(base + bank->regs->leveldetect0, gpio_bit, trigger & IRQ_TYPE_LEVEL_LOW); omap_gpio_rmw(base + bank->regs->leveldetect1, gpio_bit, trigger & IRQ_TYPE_LEVEL_HIGH); /* * We need the edge detection enabled for to allow the GPIO block * to be woken from idle state. Set the appropriate edge detection * in addition to the level detection. */ omap_gpio_rmw(base + bank->regs->risingdetect, gpio_bit, trigger & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_HIGH)); omap_gpio_rmw(base + bank->regs->fallingdetect, gpio_bit, trigger & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_LEVEL_LOW)); bank->context.leveldetect0 = readl_relaxed(bank->base + bank->regs->leveldetect0); bank->context.leveldetect1 = readl_relaxed(bank->base + bank->regs->leveldetect1); bank->context.risingdetect = readl_relaxed(bank->base + bank->regs->risingdetect); bank->context.fallingdetect = readl_relaxed(bank->base + bank->regs->fallingdetect); bank->level_mask = bank->context.leveldetect0 | bank->context.leveldetect1; /* This part needs to be executed always for OMAP{34xx, 44xx} */ if (!bank->regs->irqctrl && !omap_gpio_is_off_wakeup_capable(bank, gpio)) { /* * Log the edge gpio and manually trigger the IRQ * after resume if the input level changes * to avoid irq lost during PER RET/OFF mode * Applies for omap2 non-wakeup gpio and all omap3 gpios */ if (trigger & IRQ_TYPE_EDGE_BOTH) bank->enabled_non_wakeup_gpios |= gpio_bit; else bank->enabled_non_wakeup_gpios &= ~gpio_bit; } } /* * This only applies to chips that can't do both rising and falling edge * detection at once. For all other chips, this function is a noop. */ static void omap_toggle_gpio_edge_triggering(struct gpio_bank *bank, int gpio) { if (IS_ENABLED(CONFIG_ARCH_OMAP1) && bank->regs->irqctrl) { void __iomem *reg = bank->base + bank->regs->irqctrl; writel_relaxed(readl_relaxed(reg) ^ BIT(gpio), reg); } } static int omap_set_gpio_triggering(struct gpio_bank *bank, int gpio, unsigned trigger) { void __iomem *reg = bank->base; u32 l = 0; if (bank->regs->leveldetect0 && bank->regs->wkup_en) { omap_set_gpio_trigger(bank, gpio, trigger); } else if (bank->regs->irqctrl) { reg += bank->regs->irqctrl; l = readl_relaxed(reg); if ((trigger & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH) bank->toggle_mask |= BIT(gpio); if (trigger & IRQ_TYPE_EDGE_RISING) l |= BIT(gpio); else if (trigger & IRQ_TYPE_EDGE_FALLING) l &= ~(BIT(gpio)); else return -EINVAL; writel_relaxed(l, reg); } else if (bank->regs->edgectrl1) { if (gpio & 0x08) reg += bank->regs->edgectrl2; else reg += bank->regs->edgectrl1; gpio &= 0x07; l = readl_relaxed(reg); l &= ~(3 << (gpio << 1)); if (trigger & IRQ_TYPE_EDGE_RISING) l |= 2 << (gpio << 1); if (trigger & IRQ_TYPE_EDGE_FALLING) l |= BIT(gpio << 1); writel_relaxed(l, reg); } return 0; } static void omap_enable_gpio_module(struct gpio_bank *bank, unsigned offset) { if (bank->regs->pinctrl) { void __iomem *reg = bank->base + bank->regs->pinctrl; /* Claim the pin for MPU */ writel_relaxed(readl_relaxed(reg) | (BIT(offset)), reg); } if (bank->regs->ctrl && !BANK_USED(bank)) { void __iomem *reg = bank->base + bank->regs->ctrl; u32 ctrl; ctrl = readl_relaxed(reg); /* Module is enabled, clocks are not gated */ ctrl &= ~GPIO_MOD_CTRL_BIT; writel_relaxed(ctrl, reg); bank->context.ctrl = ctrl; } } static void omap_disable_gpio_module(struct gpio_bank *bank, unsigned offset) { if (bank->regs->ctrl && !BANK_USED(bank)) { void __iomem *reg = bank->base + bank->regs->ctrl; u32 ctrl; ctrl = readl_relaxed(reg); /* Module is disabled, clocks are gated */ ctrl |= GPIO_MOD_CTRL_BIT; writel_relaxed(ctrl, reg); bank->context.ctrl = ctrl; } } static int omap_gpio_is_input(struct gpio_bank *bank, unsigned offset) { void __iomem *reg = bank->base + bank->regs->direction; return readl_relaxed(reg) & BIT(offset); } static void omap_gpio_init_irq(struct gpio_bank *bank, unsigned offset) { if (!LINE_USED(bank->mod_usage, offset)) { omap_enable_gpio_module(bank, offset); omap_set_gpio_direction(bank, offset, 1); } bank->irq_usage |= BIT(offset); } static int omap_gpio_irq_type(struct irq_data *d, unsigned type) { struct gpio_bank *bank = omap_irq_data_get_bank(d); int retval; unsigned long flags; unsigned offset = d->hwirq; if (type & ~IRQ_TYPE_SENSE_MASK) return -EINVAL; if (!bank->regs->leveldetect0 && (type & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH))) return -EINVAL; raw_spin_lock_irqsave(&bank->lock, flags); retval = omap_set_gpio_triggering(bank, offset, type); if (retval) { raw_spin_unlock_irqrestore(&bank->lock, flags); goto error; } omap_gpio_init_irq(bank, offset); if (!omap_gpio_is_input(bank, offset)) { raw_spin_unlock_irqrestore(&bank->lock, flags); retval = -EINVAL; goto error; } raw_spin_unlock_irqrestore(&bank->lock, flags); if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) irq_set_handler_locked(d, handle_level_irq); else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)) /* * Edge IRQs are already cleared/acked in irq_handler and * not need to be masked, as result handle_edge_irq() * logic is excessed here and may cause lose of interrupts. * So just use handle_simple_irq. */ irq_set_handler_locked(d, handle_simple_irq); return 0; error: return retval; } static void omap_clear_gpio_irqbank(struct gpio_bank *bank, int gpio_mask) { void __iomem *reg = bank->base; reg += bank->regs->irqstatus; writel_relaxed(gpio_mask, reg); /* Workaround for clearing DSP GPIO interrupts to allow retention */ if (bank->regs->irqstatus2) { reg = bank->base + bank->regs->irqstatus2; writel_relaxed(gpio_mask, reg); } /* Flush posted write for the irq status to avoid spurious interrupts */ readl_relaxed(reg); } static inline void omap_clear_gpio_irqstatus(struct gpio_bank *bank, unsigned offset) { omap_clear_gpio_irqbank(bank, BIT(offset)); } static u32 omap_get_gpio_irqbank_mask(struct gpio_bank *bank) { void __iomem *reg = bank->base; u32 l; u32 mask = (BIT(bank->width)) - 1; reg += bank->regs->irqenable; l = readl_relaxed(reg); if (bank->regs->irqenable_inv) l = ~l; l &= mask; return l; } static inline void omap_set_gpio_irqenable(struct gpio_bank *bank, unsigned offset, int enable) { void __iomem *reg = bank->base; u32 gpio_mask = BIT(offset); if (bank->regs->set_irqenable && bank->regs->clr_irqenable) { if (enable) { reg += bank->regs->set_irqenable; bank->context.irqenable1 |= gpio_mask; } else { reg += bank->regs->clr_irqenable; bank->context.irqenable1 &= ~gpio_mask; } writel_relaxed(gpio_mask, reg); } else { bank->context.irqenable1 = omap_gpio_rmw(reg + bank->regs->irqenable, gpio_mask, enable ^ bank->regs->irqenable_inv); } /* * Program GPIO wakeup along with IRQ enable to satisfy OMAP4430 TRM * note requiring correlation between the IRQ enable registers and * the wakeup registers. In any case, we want wakeup from idle * enabled for the GPIOs which support this feature. */ if (bank->regs->wkup_en && (bank->regs->edgectrl1 || !(bank->non_wakeup_gpios & gpio_mask))) { bank->context.wake_en = omap_gpio_rmw(bank->base + bank->regs->wkup_en, gpio_mask, enable); } } /* Use disable_irq_wake() and enable_irq_wake() functions from drivers */ static int omap_gpio_wake_enable(struct irq_data *d, unsigned int enable) { struct gpio_bank *bank = omap_irq_data_get_bank(d); return irq_set_irq_wake(bank->irq, enable); } /* * We need to unmask the GPIO bank interrupt as soon as possible to * avoid missing GPIO interrupts for other lines in the bank. * Then we need to mask-read-clear-unmask the triggered GPIO lines * in the bank to avoid missing nested interrupts for a GPIO line. * If we wait to unmask individual GPIO lines in the bank after the * line's interrupt handler has been run, we may miss some nested * interrupts. */ static irqreturn_t omap_gpio_irq_handler(int irq, void *gpiobank) { void __iomem *isr_reg = NULL; u32 enabled, isr, edge; unsigned int bit; struct gpio_bank *bank = gpiobank; unsigned long wa_lock_flags; unsigned long lock_flags; isr_reg = bank->base + bank->regs->irqstatus; if (WARN_ON(!isr_reg)) goto exit; if (WARN_ONCE(!pm_runtime_active(bank->chip.parent), "gpio irq%i while runtime suspended?\n", irq)) return IRQ_NONE; while (1) { raw_spin_lock_irqsave(&bank->lock, lock_flags); enabled = omap_get_gpio_irqbank_mask(bank); isr = readl_relaxed(isr_reg) & enabled; /* * Clear edge sensitive interrupts before calling handler(s) * so subsequent edge transitions are not missed while the * handlers are running. */ edge = isr & ~bank->level_mask; if (edge) omap_clear_gpio_irqbank(bank, edge); raw_spin_unlock_irqrestore(&bank->lock, lock_flags); if (!isr) break; while (isr) { bit = __ffs(isr); isr &= ~(BIT(bit)); raw_spin_lock_irqsave(&bank->lock, lock_flags); /* * Some chips can't respond to both rising and falling * at the same time. If this irq was requested with * both flags, we need to flip the ICR data for the IRQ * to respond to the IRQ for the opposite direction. * This will be indicated in the bank toggle_mask. */ if (bank->toggle_mask & (BIT(bit))) omap_toggle_gpio_edge_triggering(bank, bit); raw_spin_unlock_irqrestore(&bank->lock, lock_flags); raw_spin_lock_irqsave(&bank->wa_lock, wa_lock_flags); generic_handle_domain_irq(bank->chip.irq.domain, bit); raw_spin_unlock_irqrestore(&bank->wa_lock, wa_lock_flags); } } exit: return IRQ_HANDLED; } static unsigned int omap_gpio_irq_startup(struct irq_data *d) { struct gpio_bank *bank = omap_irq_data_get_bank(d); unsigned long flags; unsigned offset = d->hwirq; raw_spin_lock_irqsave(&bank->lock, flags); if (!LINE_USED(bank->mod_usage, offset)) omap_set_gpio_direction(bank, offset, 1); omap_enable_gpio_module(bank, offset); bank->irq_usage |= BIT(offset); raw_spin_unlock_irqrestore(&bank->lock, flags); omap_gpio_unmask_irq(d); return 0; } static void omap_gpio_irq_shutdown(struct irq_data *d) { struct gpio_bank *bank = omap_irq_data_get_bank(d); unsigned long flags; unsigned offset = d->hwirq; raw_spin_lock_irqsave(&bank->lock, flags); bank->irq_usage &= ~(BIT(offset)); omap_set_gpio_triggering(bank, offset, IRQ_TYPE_NONE); omap_clear_gpio_irqstatus(bank, offset); omap_set_gpio_irqenable(bank, offset, 0); if (!LINE_USED(bank->mod_usage, offset)) omap_clear_gpio_debounce(bank, offset); omap_disable_gpio_module(bank, offset); raw_spin_unlock_irqrestore(&bank->lock, flags); } static void omap_gpio_irq_bus_lock(struct irq_data *data) { struct gpio_bank *bank = omap_irq_data_get_bank(data); pm_runtime_get_sync(bank->chip.parent); } static void gpio_irq_bus_sync_unlock(struct irq_data *data) { struct gpio_bank *bank = omap_irq_data_get_bank(data); pm_runtime_put(bank->chip.parent); } static void omap_gpio_mask_irq(struct irq_data *d) { struct gpio_bank *bank = omap_irq_data_get_bank(d); unsigned offset = d->hwirq; unsigned long flags; raw_spin_lock_irqsave(&bank->lock, flags); omap_set_gpio_triggering(bank, offset, IRQ_TYPE_NONE); omap_set_gpio_irqenable(bank, offset, 0); raw_spin_unlock_irqrestore(&bank->lock, flags); gpiochip_disable_irq(&bank->chip, offset); } static void omap_gpio_unmask_irq(struct irq_data *d) { struct gpio_bank *bank = omap_irq_data_get_bank(d); unsigned offset = d->hwirq; u32 trigger = irqd_get_trigger_type(d); unsigned long flags; gpiochip_enable_irq(&bank->chip, offset); raw_spin_lock_irqsave(&bank->lock, flags); omap_set_gpio_irqenable(bank, offset, 1); /* * For level-triggered GPIOs, clearing must be done after the source * is cleared, thus after the handler has run. OMAP4 needs this done * after enabing the interrupt to clear the wakeup status. */ if (bank->regs->leveldetect0 && bank->regs->wkup_en && trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) omap_clear_gpio_irqstatus(bank, offset); if (trigger) omap_set_gpio_triggering(bank, offset, trigger); raw_spin_unlock_irqrestore(&bank->lock, flags); } static void omap_gpio_irq_print_chip(struct irq_data *d, struct seq_file *p) { struct gpio_bank *bank = omap_irq_data_get_bank(d); seq_printf(p, dev_name(bank->dev)); } static const struct irq_chip omap_gpio_irq_chip = { .irq_startup = omap_gpio_irq_startup, .irq_shutdown = omap_gpio_irq_shutdown, .irq_mask = omap_gpio_mask_irq, .irq_unmask = omap_gpio_unmask_irq, .irq_set_type = omap_gpio_irq_type, .irq_set_wake = omap_gpio_wake_enable, .irq_bus_lock = omap_gpio_irq_bus_lock, .irq_bus_sync_unlock = gpio_irq_bus_sync_unlock, .irq_print_chip = omap_gpio_irq_print_chip, .flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_IMMUTABLE, GPIOCHIP_IRQ_RESOURCE_HELPERS, }; static const struct irq_chip omap_gpio_irq_chip_nowake = { .irq_startup = omap_gpio_irq_startup, .irq_shutdown = omap_gpio_irq_shutdown, .irq_mask = omap_gpio_mask_irq, .irq_unmask = omap_gpio_unmask_irq, .irq_set_type = omap_gpio_irq_type, .irq_bus_lock = omap_gpio_irq_bus_lock, .irq_bus_sync_unlock = gpio_irq_bus_sync_unlock, .irq_print_chip = omap_gpio_irq_print_chip, .flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_IMMUTABLE, GPIOCHIP_IRQ_RESOURCE_HELPERS, }; /*---------------------------------------------------------------------*/ static int omap_mpuio_suspend_noirq(struct device *dev) { struct gpio_bank *bank = dev_get_drvdata(dev); void __iomem *mask_reg = bank->base + OMAP_MPUIO_GPIO_MASKIT / bank->stride; unsigned long flags; raw_spin_lock_irqsave(&bank->lock, flags); writel_relaxed(0xffff & ~bank->context.wake_en, mask_reg); raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } static int omap_mpuio_resume_noirq(struct device *dev) { struct gpio_bank *bank = dev_get_drvdata(dev); void __iomem *mask_reg = bank->base + OMAP_MPUIO_GPIO_MASKIT / bank->stride; unsigned long flags; raw_spin_lock_irqsave(&bank->lock, flags); writel_relaxed(bank->context.wake_en, mask_reg); raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } static const struct dev_pm_ops omap_mpuio_dev_pm_ops = { .suspend_noirq = omap_mpuio_suspend_noirq, .resume_noirq = omap_mpuio_resume_noirq, }; /* use platform_driver for this. */ static struct platform_driver omap_mpuio_driver = { .driver = { .name = "mpuio", .pm = &omap_mpuio_dev_pm_ops, }, }; static struct platform_device omap_mpuio_device = { .name = "mpuio", .id = -1, .dev = { .driver = &omap_mpuio_driver.driver, } /* could list the /proc/iomem resources */ }; static inline void omap_mpuio_init(struct gpio_bank *bank) { platform_set_drvdata(&omap_mpuio_device, bank); if (platform_driver_register(&omap_mpuio_driver) == 0) (void) platform_device_register(&omap_mpuio_device); } /*---------------------------------------------------------------------*/ static int omap_gpio_request(struct gpio_chip *chip, unsigned offset) { struct gpio_bank *bank = gpiochip_get_data(chip); unsigned long flags; pm_runtime_get_sync(chip->parent); raw_spin_lock_irqsave(&bank->lock, flags); omap_enable_gpio_module(bank, offset); bank->mod_usage |= BIT(offset); raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } static void omap_gpio_free(struct gpio_chip *chip, unsigned offset) { struct gpio_bank *bank = gpiochip_get_data(chip); unsigned long flags; raw_spin_lock_irqsave(&bank->lock, flags); bank->mod_usage &= ~(BIT(offset)); if (!LINE_USED(bank->irq_usage, offset)) { omap_set_gpio_direction(bank, offset, 1); omap_clear_gpio_debounce(bank, offset); } omap_disable_gpio_module(bank, offset); raw_spin_unlock_irqrestore(&bank->lock, flags); pm_runtime_put(chip->parent); } static int omap_gpio_get_direction(struct gpio_chip *chip, unsigned offset) { struct gpio_bank *bank = gpiochip_get_data(chip); if (readl_relaxed(bank->base + bank->regs->direction) & BIT(offset)) return GPIO_LINE_DIRECTION_IN; return GPIO_LINE_DIRECTION_OUT; } static int omap_gpio_input(struct gpio_chip *chip, unsigned offset) { struct gpio_bank *bank; unsigned long flags; bank = gpiochip_get_data(chip); raw_spin_lock_irqsave(&bank->lock, flags); omap_set_gpio_direction(bank, offset, 1); raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } static int omap_gpio_get(struct gpio_chip *chip, unsigned offset) { struct gpio_bank *bank = gpiochip_get_data(chip); void __iomem *reg; if (omap_gpio_is_input(bank, offset)) reg = bank->base + bank->regs->datain; else reg = bank->base + bank->regs->dataout; return (readl_relaxed(reg) & BIT(offset)) != 0; } static int omap_gpio_output(struct gpio_chip *chip, unsigned offset, int value) { struct gpio_bank *bank; unsigned long flags; bank = gpiochip_get_data(chip); raw_spin_lock_irqsave(&bank->lock, flags); bank->set_dataout(bank, offset, value); omap_set_gpio_direction(bank, offset, 0); raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } static int omap_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask, unsigned long *bits) { struct gpio_bank *bank = gpiochip_get_data(chip); void __iomem *base = bank->base; u32 direction, m, val = 0; direction = readl_relaxed(base + bank->regs->direction); m = direction & *mask; if (m) val |= readl_relaxed(base + bank->regs->datain) & m; m = ~direction & *mask; if (m) val |= readl_relaxed(base + bank->regs->dataout) & m; *bits = val; return 0; } static int omap_gpio_debounce(struct gpio_chip *chip, unsigned offset, unsigned debounce) { struct gpio_bank *bank; unsigned long flags; int ret; bank = gpiochip_get_data(chip); raw_spin_lock_irqsave(&bank->lock, flags); ret = omap2_set_gpio_debounce(bank, offset, debounce); raw_spin_unlock_irqrestore(&bank->lock, flags); if (ret) dev_info(chip->parent, "Could not set line %u debounce to %u microseconds (%d)", offset, debounce, ret); return ret; } static int omap_gpio_set_config(struct gpio_chip *chip, unsigned offset, unsigned long config) { u32 debounce; int ret = -ENOTSUPP; switch (pinconf_to_config_param(config)) { case PIN_CONFIG_BIAS_DISABLE: case PIN_CONFIG_BIAS_PULL_UP: case PIN_CONFIG_BIAS_PULL_DOWN: ret = gpiochip_generic_config(chip, offset, config); break; case PIN_CONFIG_INPUT_DEBOUNCE: debounce = pinconf_to_config_argument(config); ret = omap_gpio_debounce(chip, offset, debounce); break; default: break; } return ret; } static void omap_gpio_set(struct gpio_chip *chip, unsigned offset, int value) { struct gpio_bank *bank; unsigned long flags; bank = gpiochip_get_data(chip); raw_spin_lock_irqsave(&bank->lock, flags); bank->set_dataout(bank, offset, value); raw_spin_unlock_irqrestore(&bank->lock, flags); } static void omap_gpio_set_multiple(struct gpio_chip *chip, unsigned long *mask, unsigned long *bits) { struct gpio_bank *bank = gpiochip_get_data(chip); void __iomem *reg = bank->base + bank->regs->dataout; unsigned long flags; u32 l; raw_spin_lock_irqsave(&bank->lock, flags); l = (readl_relaxed(reg) & ~*mask) | (*bits & *mask); writel_relaxed(l, reg); bank->context.dataout = l; raw_spin_unlock_irqrestore(&bank->lock, flags); } /*---------------------------------------------------------------------*/ static void omap_gpio_show_rev(struct gpio_bank *bank) { static bool called; u32 rev; if (called || bank->regs->revision == USHRT_MAX) return; rev = readw_relaxed(bank->base + bank->regs->revision); pr_info("OMAP GPIO hardware version %d.%d\n", (rev >> 4) & 0x0f, rev & 0x0f); called = true; } static void omap_gpio_mod_init(struct gpio_bank *bank) { void __iomem *base = bank->base; u32 l = 0xffffffff; if (bank->width == 16) l = 0xffff; if (bank->is_mpuio) { writel_relaxed(l, bank->base + bank->regs->irqenable); return; } omap_gpio_rmw(base + bank->regs->irqenable, l, bank->regs->irqenable_inv); omap_gpio_rmw(base + bank->regs->irqstatus, l, !bank->regs->irqenable_inv); if (bank->regs->debounce_en) writel_relaxed(0, base + bank->regs->debounce_en); /* Save OE default value (0xffffffff) in the context */ bank->context.oe = readl_relaxed(bank->base + bank->regs->direction); /* Initialize interface clk ungated, module enabled */ if (bank->regs->ctrl) writel_relaxed(0, base + bank->regs->ctrl); } static int omap_gpio_chip_init(struct gpio_bank *bank, struct device *pm_dev) { struct gpio_irq_chip *irq; static int gpio; const char *label; int ret; /* * REVISIT eventually switch from OMAP-specific gpio structs * over to the generic ones */ bank->chip.request = omap_gpio_request; bank->chip.free = omap_gpio_free; bank->chip.get_direction = omap_gpio_get_direction; bank->chip.direction_input = omap_gpio_input; bank->chip.get = omap_gpio_get; bank->chip.get_multiple = omap_gpio_get_multiple; bank->chip.direction_output = omap_gpio_output; bank->chip.set_config = omap_gpio_set_config; bank->chip.set = omap_gpio_set; bank->chip.set_multiple = omap_gpio_set_multiple; if (bank->is_mpuio) { bank->chip.label = "mpuio"; if (bank->regs->wkup_en) bank->chip.parent = &omap_mpuio_device.dev; bank->chip.base = OMAP_MPUIO(0); } else { label = devm_kasprintf(bank->chip.parent, GFP_KERNEL, "gpio-%d-%d", gpio, gpio + bank->width - 1); if (!label) return -ENOMEM; bank->chip.label = label; bank->chip.base = -1; } bank->chip.ngpio = bank->width; irq = &bank->chip.irq; /* MPUIO is a bit different, reading IRQ status clears it */ if (bank->is_mpuio && !bank->regs->wkup_en) gpio_irq_chip_set_chip(irq, &omap_gpio_irq_chip_nowake); else gpio_irq_chip_set_chip(irq, &omap_gpio_irq_chip); irq->handler = handle_bad_irq; irq->default_type = IRQ_TYPE_NONE; irq->num_parents = 1; irq->parents = &bank->irq; ret = gpiochip_add_data(&bank->chip, bank); if (ret) return dev_err_probe(bank->chip.parent, ret, "Could not register gpio chip\n"); irq_domain_set_pm_device(bank->chip.irq.domain, pm_dev); ret = devm_request_irq(bank->chip.parent, bank->irq, omap_gpio_irq_handler, 0, dev_name(bank->chip.parent), bank); if (ret) gpiochip_remove(&bank->chip); if (!bank->is_mpuio) gpio += bank->width; return ret; } static void omap_gpio_init_context(struct gpio_bank *p) { const struct omap_gpio_reg_offs *regs = p->regs; void __iomem *base = p->base; p->context.sysconfig = readl_relaxed(base + regs->sysconfig); p->context.ctrl = readl_relaxed(base + regs->ctrl); p->context.oe = readl_relaxed(base + regs->direction); p->context.wake_en = readl_relaxed(base + regs->wkup_en); p->context.leveldetect0 = readl_relaxed(base + regs->leveldetect0); p->context.leveldetect1 = readl_relaxed(base + regs->leveldetect1); p->context.risingdetect = readl_relaxed(base + regs->risingdetect); p->context.fallingdetect = readl_relaxed(base + regs->fallingdetect); p->context.irqenable1 = readl_relaxed(base + regs->irqenable); p->context.irqenable2 = readl_relaxed(base + regs->irqenable2); p->context.dataout = readl_relaxed(base + regs->dataout); p->context_valid = true; } static void omap_gpio_restore_context(struct gpio_bank *bank) { const struct omap_gpio_reg_offs *regs = bank->regs; void __iomem *base = bank->base; writel_relaxed(bank->context.sysconfig, base + regs->sysconfig); writel_relaxed(bank->context.wake_en, base + regs->wkup_en); writel_relaxed(bank->context.ctrl, base + regs->ctrl); writel_relaxed(bank->context.leveldetect0, base + regs->leveldetect0); writel_relaxed(bank->context.leveldetect1, base + regs->leveldetect1); writel_relaxed(bank->context.risingdetect, base + regs->risingdetect); writel_relaxed(bank->context.fallingdetect, base + regs->fallingdetect); writel_relaxed(bank->context.dataout, base + regs->dataout); writel_relaxed(bank->context.oe, base + regs->direction); if (bank->dbck_enable_mask) { writel_relaxed(bank->context.debounce, base + regs->debounce); writel_relaxed(bank->context.debounce_en, base + regs->debounce_en); } writel_relaxed(bank->context.irqenable1, base + regs->irqenable); writel_relaxed(bank->context.irqenable2, base + regs->irqenable2); } static void omap_gpio_idle(struct gpio_bank *bank, bool may_lose_context) { struct device *dev = bank->chip.parent; void __iomem *base = bank->base; u32 mask, nowake; bank->saved_datain = readl_relaxed(base + bank->regs->datain); /* Save syconfig, it's runtime value can be different from init value */ if (bank->loses_context) bank->context.sysconfig = readl_relaxed(base + bank->regs->sysconfig); if (!bank->enabled_non_wakeup_gpios) goto update_gpio_context_count; /* Check for pending EDGE_FALLING, ignore EDGE_BOTH */ mask = bank->enabled_non_wakeup_gpios & bank->context.fallingdetect; mask &= ~bank->context.risingdetect; bank->saved_datain |= mask; /* Check for pending EDGE_RISING, ignore EDGE_BOTH */ mask = bank->enabled_non_wakeup_gpios & bank->context.risingdetect; mask &= ~bank->context.fallingdetect; bank->saved_datain &= ~mask; if (!may_lose_context) goto update_gpio_context_count; /* * If going to OFF, remove triggering for all wkup domain * non-wakeup GPIOs. Otherwise spurious IRQs will be * generated. See OMAP2420 Errata item 1.101. */ if (!bank->loses_context && bank->enabled_non_wakeup_gpios) { nowake = bank->enabled_non_wakeup_gpios; omap_gpio_rmw(base + bank->regs->fallingdetect, nowake, ~nowake); omap_gpio_rmw(base + bank->regs->risingdetect, nowake, ~nowake); } update_gpio_context_count: if (bank->get_context_loss_count) bank->context_loss_count = bank->get_context_loss_count(dev); omap_gpio_dbck_disable(bank); } static void omap_gpio_unidle(struct gpio_bank *bank) { struct device *dev = bank->chip.parent; u32 l = 0, gen, gen0, gen1; int c; /* * On the first resume during the probe, the context has not * been initialised and so initialise it now. Also initialise * the context loss count. */ if (bank->loses_context && !bank->context_valid) { omap_gpio_init_context(bank); if (bank->get_context_loss_count) bank->context_loss_count = bank->get_context_loss_count(dev); } omap_gpio_dbck_enable(bank); if (bank->loses_context) { if (!bank->get_context_loss_count) { omap_gpio_restore_context(bank); } else { c = bank->get_context_loss_count(dev); if (c != bank->context_loss_count) { omap_gpio_restore_context(bank); } else { return; } } } else { /* Restore changes done for OMAP2420 errata 1.101 */ writel_relaxed(bank->context.fallingdetect, bank->base + bank->regs->fallingdetect); writel_relaxed(bank->context.risingdetect, bank->base + bank->regs->risingdetect); } l = readl_relaxed(bank->base + bank->regs->datain); /* * Check if any of the non-wakeup interrupt GPIOs have changed * state. If so, generate an IRQ by software. This is * horribly racy, but it's the best we can do to work around * this silicon bug. */ l ^= bank->saved_datain; l &= bank->enabled_non_wakeup_gpios; /* * No need to generate IRQs for the rising edge for gpio IRQs * configured with falling edge only; and vice versa. */ gen0 = l & bank->context.fallingdetect; gen0 &= bank->saved_datain; gen1 = l & bank->context.risingdetect; gen1 &= ~(bank->saved_datain); /* FIXME: Consider GPIO IRQs with level detections properly! */ gen = l & (~(bank->context.fallingdetect) & ~(bank->context.risingdetect)); /* Consider all GPIO IRQs needed to be updated */ gen |= gen0 | gen1; if (gen) { u32 old0, old1; old0 = readl_relaxed(bank->base + bank->regs->leveldetect0); old1 = readl_relaxed(bank->base + bank->regs->leveldetect1); if (!bank->regs->irqstatus_raw0) { writel_relaxed(old0 | gen, bank->base + bank->regs->leveldetect0); writel_relaxed(old1 | gen, bank->base + bank->regs->leveldetect1); } if (bank->regs->irqstatus_raw0) { writel_relaxed(old0 | l, bank->base + bank->regs->leveldetect0); writel_relaxed(old1 | l, bank->base + bank->regs->leveldetect1); } writel_relaxed(old0, bank->base + bank->regs->leveldetect0); writel_relaxed(old1, bank->base + bank->regs->leveldetect1); } } static int gpio_omap_cpu_notifier(struct notifier_block *nb, unsigned long cmd, void *v) { struct gpio_bank *bank; unsigned long flags; int ret = NOTIFY_OK; u32 isr, mask; bank = container_of(nb, struct gpio_bank, nb); raw_spin_lock_irqsave(&bank->lock, flags); if (bank->is_suspended) goto out_unlock; switch (cmd) { case CPU_CLUSTER_PM_ENTER: mask = omap_get_gpio_irqbank_mask(bank); isr = readl_relaxed(bank->base + bank->regs->irqstatus) & mask; if (isr) { ret = NOTIFY_BAD; break; } omap_gpio_idle(bank, true); break; case CPU_CLUSTER_PM_ENTER_FAILED: case CPU_CLUSTER_PM_EXIT: omap_gpio_unidle(bank); break; } out_unlock: raw_spin_unlock_irqrestore(&bank->lock, flags); return ret; } static const struct omap_gpio_reg_offs omap2_gpio_regs = { .revision = OMAP24XX_GPIO_REVISION, .sysconfig = OMAP24XX_GPIO_SYSCONFIG, .direction = OMAP24XX_GPIO_OE, .datain = OMAP24XX_GPIO_DATAIN, .dataout = OMAP24XX_GPIO_DATAOUT, .set_dataout = OMAP24XX_GPIO_SETDATAOUT, .clr_dataout = OMAP24XX_GPIO_CLEARDATAOUT, .irqstatus = OMAP24XX_GPIO_IRQSTATUS1, .irqstatus2 = OMAP24XX_GPIO_IRQSTATUS2, .irqenable = OMAP24XX_GPIO_IRQENABLE1, .irqenable2 = OMAP24XX_GPIO_IRQENABLE2, .set_irqenable = OMAP24XX_GPIO_SETIRQENABLE1, .clr_irqenable = OMAP24XX_GPIO_CLEARIRQENABLE1, .debounce = OMAP24XX_GPIO_DEBOUNCE_VAL, .debounce_en = OMAP24XX_GPIO_DEBOUNCE_EN, .ctrl = OMAP24XX_GPIO_CTRL, .wkup_en = OMAP24XX_GPIO_WAKE_EN, .leveldetect0 = OMAP24XX_GPIO_LEVELDETECT0, .leveldetect1 = OMAP24XX_GPIO_LEVELDETECT1, .risingdetect = OMAP24XX_GPIO_RISINGDETECT, .fallingdetect = OMAP24XX_GPIO_FALLINGDETECT, }; static const struct omap_gpio_reg_offs omap4_gpio_regs = { .revision = OMAP4_GPIO_REVISION, .sysconfig = OMAP4_GPIO_SYSCONFIG, .direction = OMAP4_GPIO_OE, .datain = OMAP4_GPIO_DATAIN, .dataout = OMAP4_GPIO_DATAOUT, .set_dataout = OMAP4_GPIO_SETDATAOUT, .clr_dataout = OMAP4_GPIO_CLEARDATAOUT, .irqstatus = OMAP4_GPIO_IRQSTATUS0, .irqstatus2 = OMAP4_GPIO_IRQSTATUS1, .irqstatus_raw0 = OMAP4_GPIO_IRQSTATUSRAW0, .irqstatus_raw1 = OMAP4_GPIO_IRQSTATUSRAW1, .irqenable = OMAP4_GPIO_IRQSTATUSSET0, .irqenable2 = OMAP4_GPIO_IRQSTATUSSET1, .set_irqenable = OMAP4_GPIO_IRQSTATUSSET0, .clr_irqenable = OMAP4_GPIO_IRQSTATUSCLR0, .debounce = OMAP4_GPIO_DEBOUNCINGTIME, .debounce_en = OMAP4_GPIO_DEBOUNCENABLE, .ctrl = OMAP4_GPIO_CTRL, .wkup_en = OMAP4_GPIO_IRQWAKEN0, .leveldetect0 = OMAP4_GPIO_LEVELDETECT0, .leveldetect1 = OMAP4_GPIO_LEVELDETECT1, .risingdetect = OMAP4_GPIO_RISINGDETECT, .fallingdetect = OMAP4_GPIO_FALLINGDETECT, }; static const struct omap_gpio_platform_data omap2_pdata = { .regs = &omap2_gpio_regs, .bank_width = 32, .dbck_flag = false, }; static const struct omap_gpio_platform_data omap3_pdata = { .regs = &omap2_gpio_regs, .bank_width = 32, .dbck_flag = true, }; static const struct omap_gpio_platform_data omap4_pdata = { .regs = &omap4_gpio_regs, .bank_width = 32, .dbck_flag = true, }; static const struct of_device_id omap_gpio_match[] = { { .compatible = "ti,omap4-gpio", .data = &omap4_pdata, }, { .compatible = "ti,omap3-gpio", .data = &omap3_pdata, }, { .compatible = "ti,omap2-gpio", .data = &omap2_pdata, }, { }, }; MODULE_DEVICE_TABLE(of, omap_gpio_match); static int omap_gpio_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device_node *node = dev->of_node; const struct omap_gpio_platform_data *pdata; struct gpio_bank *bank; int ret; pdata = device_get_match_data(dev); pdata = pdata ?: dev_get_platdata(dev); if (!pdata) return -EINVAL; bank = devm_kzalloc(dev, sizeof(*bank), GFP_KERNEL); if (!bank) return -ENOMEM; bank->dev = dev; bank->irq = platform_get_irq(pdev, 0); if (bank->irq < 0) return bank->irq; bank->chip.parent = dev; bank->chip.owner = THIS_MODULE; bank->dbck_flag = pdata->dbck_flag; bank->stride = pdata->bank_stride; bank->width = pdata->bank_width; bank->is_mpuio = pdata->is_mpuio; bank->non_wakeup_gpios = pdata->non_wakeup_gpios; bank->regs = pdata->regs; if (node) { if (!of_property_read_bool(node, "ti,gpio-always-on")) bank->loses_context = true; } else { bank->loses_context = pdata->loses_context; if (bank->loses_context) bank->get_context_loss_count = pdata->get_context_loss_count; } if (bank->regs->set_dataout && bank->regs->clr_dataout) bank->set_dataout = omap_set_gpio_dataout_reg; else bank->set_dataout = omap_set_gpio_dataout_mask; raw_spin_lock_init(&bank->lock); raw_spin_lock_init(&bank->wa_lock); /* Static mapping, never released */ bank->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(bank->base)) { return PTR_ERR(bank->base); } if (bank->dbck_flag) { bank->dbck = devm_clk_get(dev, "dbclk"); if (IS_ERR(bank->dbck)) { dev_err(dev, "Could not get gpio dbck. Disable debounce\n"); bank->dbck_flag = false; } else { clk_prepare(bank->dbck); } } platform_set_drvdata(pdev, bank); pm_runtime_enable(dev); pm_runtime_get_sync(dev); if (bank->is_mpuio) omap_mpuio_init(bank); omap_gpio_mod_init(bank); ret = omap_gpio_chip_init(bank, dev); if (ret) { pm_runtime_put_sync(dev); pm_runtime_disable(dev); if (bank->dbck_flag) clk_unprepare(bank->dbck); return ret; } omap_gpio_show_rev(bank); bank->nb.notifier_call = gpio_omap_cpu_notifier; cpu_pm_register_notifier(&bank->nb); pm_runtime_put(dev); return 0; } static int omap_gpio_remove(struct platform_device *pdev) { struct gpio_bank *bank = platform_get_drvdata(pdev); cpu_pm_unregister_notifier(&bank->nb); gpiochip_remove(&bank->chip); pm_runtime_disable(&pdev->dev); if (bank->dbck_flag) clk_unprepare(bank->dbck); return 0; } static int __maybe_unused omap_gpio_runtime_suspend(struct device *dev) { struct gpio_bank *bank = dev_get_drvdata(dev); unsigned long flags; raw_spin_lock_irqsave(&bank->lock, flags); omap_gpio_idle(bank, true); bank->is_suspended = true; raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } static int __maybe_unused omap_gpio_runtime_resume(struct device *dev) { struct gpio_bank *bank = dev_get_drvdata(dev); unsigned long flags; raw_spin_lock_irqsave(&bank->lock, flags); omap_gpio_unidle(bank); bank->is_suspended = false; raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } static int __maybe_unused omap_gpio_suspend(struct device *dev) { struct gpio_bank *bank = dev_get_drvdata(dev); if (bank->is_suspended) return 0; bank->needs_resume = 1; return omap_gpio_runtime_suspend(dev); } static int __maybe_unused omap_gpio_resume(struct device *dev) { struct gpio_bank *bank = dev_get_drvdata(dev); if (!bank->needs_resume) return 0; bank->needs_resume = 0; return omap_gpio_runtime_resume(dev); } static const struct dev_pm_ops gpio_pm_ops = { SET_RUNTIME_PM_OPS(omap_gpio_runtime_suspend, omap_gpio_runtime_resume, NULL) SET_LATE_SYSTEM_SLEEP_PM_OPS(omap_gpio_suspend, omap_gpio_resume) }; static struct platform_driver omap_gpio_driver = { .probe = omap_gpio_probe, .remove = omap_gpio_remove, .driver = { .name = "omap_gpio", .pm = &gpio_pm_ops, .of_match_table = omap_gpio_match, }, }; /* * gpio driver register needs to be done before * machine_init functions access gpio APIs. * Hence omap_gpio_drv_reg() is a postcore_initcall. */ static int __init omap_gpio_drv_reg(void) { return platform_driver_register(&omap_gpio_driver); } postcore_initcall(omap_gpio_drv_reg); static void __exit omap_gpio_exit(void) { platform_driver_unregister(&omap_gpio_driver); } module_exit(omap_gpio_exit); MODULE_DESCRIPTION("omap gpio driver"); MODULE_ALIAS("platform:gpio-omap"); MODULE_LICENSE("GPL v2");