// SPDX-License-Identifier: GPL-2.0-or-later /* * TI DaVinci GPIO Support * * Copyright (c) 2006-2007 David Brownell * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com> */ #include <linux/gpio/driver.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/clk.h> #include <linux/err.h> #include <linux/io.h> #include <linux/irq.h> #include <linux/irqdomain.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_device.h> #include <linux/pinctrl/consumer.h> #include <linux/platform_device.h> #include <linux/platform_data/gpio-davinci.h> #include <linux/irqchip/chained_irq.h> #include <linux/spinlock.h> #include <linux/pm_runtime.h> #define MAX_REGS_BANKS 5 #define MAX_INT_PER_BANK 32 struct davinci_gpio_regs { u32 dir; u32 out_data; u32 set_data; u32 clr_data; u32 in_data; u32 set_rising; u32 clr_rising; u32 set_falling; u32 clr_falling; u32 intstat; }; typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq); #define BINTEN 0x8 /* GPIO Interrupt Per-Bank Enable Register */ static void __iomem *gpio_base; static unsigned int offset_array[5] = {0x10, 0x38, 0x60, 0x88, 0xb0}; struct davinci_gpio_irq_data { void __iomem *regs; struct davinci_gpio_controller *chip; int bank_num; }; struct davinci_gpio_controller { struct gpio_chip chip; struct irq_domain *irq_domain; /* Serialize access to GPIO registers */ spinlock_t lock; void __iomem *regs[MAX_REGS_BANKS]; int gpio_unbanked; int irqs[MAX_INT_PER_BANK]; struct davinci_gpio_regs context[MAX_REGS_BANKS]; u32 binten_context; }; static inline u32 __gpio_mask(unsigned gpio) { return 1 << (gpio % 32); } static inline struct davinci_gpio_regs __iomem *irq2regs(struct irq_data *d) { struct davinci_gpio_regs __iomem *g; g = (__force struct davinci_gpio_regs __iomem *)irq_data_get_irq_chip_data(d); return g; } static int davinci_gpio_irq_setup(struct platform_device *pdev); /*--------------------------------------------------------------------------*/ /* board setup code *MUST* setup pinmux and enable the GPIO clock. */ static inline int __davinci_direction(struct gpio_chip *chip, unsigned offset, bool out, int value) { struct davinci_gpio_controller *d = gpiochip_get_data(chip); struct davinci_gpio_regs __iomem *g; unsigned long flags; u32 temp; int bank = offset / 32; u32 mask = __gpio_mask(offset); g = d->regs[bank]; spin_lock_irqsave(&d->lock, flags); temp = readl_relaxed(&g->dir); if (out) { temp &= ~mask; writel_relaxed(mask, value ? &g->set_data : &g->clr_data); } else { temp |= mask; } writel_relaxed(temp, &g->dir); spin_unlock_irqrestore(&d->lock, flags); return 0; } static int davinci_direction_in(struct gpio_chip *chip, unsigned offset) { return __davinci_direction(chip, offset, false, 0); } static int davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value) { return __davinci_direction(chip, offset, true, value); } /* * Read the pin's value (works even if it's set up as output); * returns zero/nonzero. * * Note that changes are synched to the GPIO clock, so reading values back * right after you've set them may give old values. */ static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset) { struct davinci_gpio_controller *d = gpiochip_get_data(chip); struct davinci_gpio_regs __iomem *g; int bank = offset / 32; g = d->regs[bank]; return !!(__gpio_mask(offset) & readl_relaxed(&g->in_data)); } /* * Assuming the pin is muxed as a gpio output, set its output value. */ static void davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value) { struct davinci_gpio_controller *d = gpiochip_get_data(chip); struct davinci_gpio_regs __iomem *g; int bank = offset / 32; g = d->regs[bank]; writel_relaxed(__gpio_mask(offset), value ? &g->set_data : &g->clr_data); } static struct davinci_gpio_platform_data * davinci_gpio_get_pdata(struct platform_device *pdev) { struct device_node *dn = pdev->dev.of_node; struct davinci_gpio_platform_data *pdata; int ret; u32 val; if (!IS_ENABLED(CONFIG_OF) || !pdev->dev.of_node) return dev_get_platdata(&pdev->dev); pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return NULL; ret = of_property_read_u32(dn, "ti,ngpio", &val); if (ret) goto of_err; pdata->ngpio = val; ret = of_property_read_u32(dn, "ti,davinci-gpio-unbanked", &val); if (ret) goto of_err; pdata->gpio_unbanked = val; return pdata; of_err: dev_err(&pdev->dev, "Populating pdata from DT failed: err %d\n", ret); return NULL; } static int davinci_gpio_probe(struct platform_device *pdev) { int bank, i, ret = 0; unsigned int ngpio, nbank, nirq; struct davinci_gpio_controller *chips; struct davinci_gpio_platform_data *pdata; struct device *dev = &pdev->dev; pdata = davinci_gpio_get_pdata(pdev); if (!pdata) { dev_err(dev, "No platform data found\n"); return -EINVAL; } dev->platform_data = pdata; /* * The gpio banks conceptually expose a segmented bitmap, * and "ngpio" is one more than the largest zero-based * bit index that's valid. */ ngpio = pdata->ngpio; if (ngpio == 0) { dev_err(dev, "How many GPIOs?\n"); return -EINVAL; } /* * If there are unbanked interrupts then the number of * interrupts is equal to number of gpios else all are banked so * number of interrupts is equal to number of banks(each with 16 gpios) */ if (pdata->gpio_unbanked) nirq = pdata->gpio_unbanked; else nirq = DIV_ROUND_UP(ngpio, 16); chips = devm_kzalloc(dev, sizeof(*chips), GFP_KERNEL); if (!chips) return -ENOMEM; gpio_base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(gpio_base)) return PTR_ERR(gpio_base); for (i = 0; i < nirq; i++) { chips->irqs[i] = platform_get_irq(pdev, i); if (chips->irqs[i] < 0) return chips->irqs[i]; } chips->chip.label = dev_name(dev); chips->chip.direction_input = davinci_direction_in; chips->chip.get = davinci_gpio_get; chips->chip.direction_output = davinci_direction_out; chips->chip.set = davinci_gpio_set; chips->chip.ngpio = ngpio; chips->chip.base = pdata->no_auto_base ? pdata->base : -1; #ifdef CONFIG_OF_GPIO chips->chip.parent = dev; chips->chip.request = gpiochip_generic_request; chips->chip.free = gpiochip_generic_free; #endif spin_lock_init(&chips->lock); nbank = DIV_ROUND_UP(ngpio, 32); for (bank = 0; bank < nbank; bank++) chips->regs[bank] = gpio_base + offset_array[bank]; ret = devm_gpiochip_add_data(dev, &chips->chip, chips); if (ret) return ret; platform_set_drvdata(pdev, chips); ret = davinci_gpio_irq_setup(pdev); if (ret) return ret; return 0; } /*--------------------------------------------------------------------------*/ /* * We expect irqs will normally be set up as input pins, but they can also be * used as output pins ... which is convenient for testing. * * NOTE: The first few GPIOs also have direct INTC hookups in addition * to their GPIOBNK0 irq, with a bit less overhead. * * All those INTC hookups (direct, plus several IRQ banks) can also * serve as EDMA event triggers. */ static void gpio_irq_disable(struct irq_data *d) { struct davinci_gpio_regs __iomem *g = irq2regs(d); uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d); writel_relaxed(mask, &g->clr_falling); writel_relaxed(mask, &g->clr_rising); } static void gpio_irq_enable(struct irq_data *d) { struct davinci_gpio_regs __iomem *g = irq2regs(d); uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d); unsigned status = irqd_get_trigger_type(d); status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING; if (!status) status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING; if (status & IRQ_TYPE_EDGE_FALLING) writel_relaxed(mask, &g->set_falling); if (status & IRQ_TYPE_EDGE_RISING) writel_relaxed(mask, &g->set_rising); } static int gpio_irq_type(struct irq_data *d, unsigned trigger) { if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)) return -EINVAL; return 0; } static struct irq_chip gpio_irqchip = { .name = "GPIO", .irq_enable = gpio_irq_enable, .irq_disable = gpio_irq_disable, .irq_set_type = gpio_irq_type, .flags = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_SKIP_SET_WAKE, }; static void gpio_irq_handler(struct irq_desc *desc) { struct davinci_gpio_regs __iomem *g; u32 mask = 0xffff; int bank_num; struct davinci_gpio_controller *d; struct davinci_gpio_irq_data *irqdata; irqdata = (struct davinci_gpio_irq_data *)irq_desc_get_handler_data(desc); bank_num = irqdata->bank_num; g = irqdata->regs; d = irqdata->chip; /* we only care about one bank */ if ((bank_num % 2) == 1) mask <<= 16; /* temporarily mask (level sensitive) parent IRQ */ chained_irq_enter(irq_desc_get_chip(desc), desc); while (1) { u32 status; int bit; irq_hw_number_t hw_irq; /* ack any irqs */ status = readl_relaxed(&g->intstat) & mask; if (!status) break; writel_relaxed(status, &g->intstat); /* now demux them to the right lowlevel handler */ while (status) { bit = __ffs(status); status &= ~BIT(bit); /* Max number of gpios per controller is 144 so * hw_irq will be in [0..143] */ hw_irq = (bank_num / 2) * 32 + bit; generic_handle_domain_irq(d->irq_domain, hw_irq); } } chained_irq_exit(irq_desc_get_chip(desc), desc); /* now it may re-trigger */ } static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset) { struct davinci_gpio_controller *d = gpiochip_get_data(chip); if (d->irq_domain) return irq_create_mapping(d->irq_domain, offset); else return -ENXIO; } static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset) { struct davinci_gpio_controller *d = gpiochip_get_data(chip); /* * NOTE: we assume for now that only irqs in the first gpio_chip * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs). */ if (offset < d->gpio_unbanked) return d->irqs[offset]; else return -ENODEV; } static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger) { struct davinci_gpio_controller *d; struct davinci_gpio_regs __iomem *g; u32 mask, i; d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data); g = (struct davinci_gpio_regs __iomem *)d->regs[0]; for (i = 0; i < MAX_INT_PER_BANK; i++) if (data->irq == d->irqs[i]) break; if (i == MAX_INT_PER_BANK) return -EINVAL; mask = __gpio_mask(i); if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)) return -EINVAL; writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING) ? &g->set_falling : &g->clr_falling); writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING) ? &g->set_rising : &g->clr_rising); return 0; } static int davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw) { struct davinci_gpio_controller *chips = (struct davinci_gpio_controller *)d->host_data; struct davinci_gpio_regs __iomem *g = chips->regs[hw / 32]; irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq, "davinci_gpio"); irq_set_irq_type(irq, IRQ_TYPE_NONE); irq_set_chip_data(irq, (__force void *)g); irq_set_handler_data(irq, (void *)(uintptr_t)__gpio_mask(hw)); return 0; } static const struct irq_domain_ops davinci_gpio_irq_ops = { .map = davinci_gpio_irq_map, .xlate = irq_domain_xlate_onetwocell, }; static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq) { static struct irq_chip_type gpio_unbanked; gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq)); return &gpio_unbanked.chip; }; static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq) { static struct irq_chip gpio_unbanked; gpio_unbanked = *irq_get_chip(irq); return &gpio_unbanked; }; static const struct of_device_id davinci_gpio_ids[]; /* * NOTE: for suspend/resume, probably best to make a platform_device with * suspend_late/resume_resume calls hooking into results of the set_wake() * calls ... so if no gpios are wakeup events the clock can be disabled, * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0 * (dm6446) can be set appropriately for GPIOV33 pins. */ static int davinci_gpio_irq_setup(struct platform_device *pdev) { unsigned gpio, bank; int irq; int ret; struct clk *clk; u32 binten = 0; unsigned ngpio; struct device *dev = &pdev->dev; struct davinci_gpio_controller *chips = platform_get_drvdata(pdev); struct davinci_gpio_platform_data *pdata = dev->platform_data; struct davinci_gpio_regs __iomem *g; struct irq_domain *irq_domain = NULL; const struct of_device_id *match; struct irq_chip *irq_chip; struct davinci_gpio_irq_data *irqdata; gpio_get_irq_chip_cb_t gpio_get_irq_chip; /* * Use davinci_gpio_get_irq_chip by default to handle non DT cases */ gpio_get_irq_chip = davinci_gpio_get_irq_chip; match = of_match_device(of_match_ptr(davinci_gpio_ids), dev); if (match) gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)match->data; ngpio = pdata->ngpio; clk = devm_clk_get(dev, "gpio"); if (IS_ERR(clk)) { dev_err(dev, "Error %ld getting gpio clock\n", PTR_ERR(clk)); return PTR_ERR(clk); } ret = clk_prepare_enable(clk); if (ret) return ret; if (!pdata->gpio_unbanked) { irq = devm_irq_alloc_descs(dev, -1, 0, ngpio, 0); if (irq < 0) { dev_err(dev, "Couldn't allocate IRQ numbers\n"); clk_disable_unprepare(clk); return irq; } irq_domain = irq_domain_add_legacy(dev->of_node, ngpio, irq, 0, &davinci_gpio_irq_ops, chips); if (!irq_domain) { dev_err(dev, "Couldn't register an IRQ domain\n"); clk_disable_unprepare(clk); return -ENODEV; } } /* * Arrange gpiod_to_irq() support, handling either direct IRQs or * banked IRQs. Having GPIOs in the first GPIO bank use direct * IRQs, while the others use banked IRQs, would need some setup * tweaks to recognize hardware which can do that. */ chips->chip.to_irq = gpio_to_irq_banked; chips->irq_domain = irq_domain; /* * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO * controller only handling trigger modes. We currently assume no * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs. */ if (pdata->gpio_unbanked) { /* pass "bank 0" GPIO IRQs to AINTC */ chips->chip.to_irq = gpio_to_irq_unbanked; chips->gpio_unbanked = pdata->gpio_unbanked; binten = GENMASK(pdata->gpio_unbanked / 16, 0); /* AINTC handles mask/unmask; GPIO handles triggering */ irq = chips->irqs[0]; irq_chip = gpio_get_irq_chip(irq); irq_chip->name = "GPIO-AINTC"; irq_chip->irq_set_type = gpio_irq_type_unbanked; /* default trigger: both edges */ g = chips->regs[0]; writel_relaxed(~0, &g->set_falling); writel_relaxed(~0, &g->set_rising); /* set the direct IRQs up to use that irqchip */ for (gpio = 0; gpio < pdata->gpio_unbanked; gpio++) { irq_set_chip(chips->irqs[gpio], irq_chip); irq_set_handler_data(chips->irqs[gpio], chips); irq_set_status_flags(chips->irqs[gpio], IRQ_TYPE_EDGE_BOTH); } goto done; } /* * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we * then chain through our own handler. */ for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 16) { /* disabled by default, enabled only as needed * There are register sets for 32 GPIOs. 2 banks of 16 * GPIOs are covered by each set of registers hence divide by 2 */ g = chips->regs[bank / 2]; writel_relaxed(~0, &g->clr_falling); writel_relaxed(~0, &g->clr_rising); /* * Each chip handles 32 gpios, and each irq bank consists of 16 * gpio irqs. Pass the irq bank's corresponding controller to * the chained irq handler. */ irqdata = devm_kzalloc(&pdev->dev, sizeof(struct davinci_gpio_irq_data), GFP_KERNEL); if (!irqdata) { clk_disable_unprepare(clk); return -ENOMEM; } irqdata->regs = g; irqdata->bank_num = bank; irqdata->chip = chips; irq_set_chained_handler_and_data(chips->irqs[bank], gpio_irq_handler, irqdata); binten |= BIT(bank); } done: /* * BINTEN -- per-bank interrupt enable. genirq would also let these * bits be set/cleared dynamically. */ writel_relaxed(binten, gpio_base + BINTEN); return 0; } static void davinci_gpio_save_context(struct davinci_gpio_controller *chips, u32 nbank) { struct davinci_gpio_regs __iomem *g; struct davinci_gpio_regs *context; u32 bank; void __iomem *base; base = chips->regs[0] - offset_array[0]; chips->binten_context = readl_relaxed(base + BINTEN); for (bank = 0; bank < nbank; bank++) { g = chips->regs[bank]; context = &chips->context[bank]; context->dir = readl_relaxed(&g->dir); context->set_data = readl_relaxed(&g->set_data); context->set_rising = readl_relaxed(&g->set_rising); context->set_falling = readl_relaxed(&g->set_falling); } /* Clear all interrupt status registers */ writel_relaxed(GENMASK(31, 0), &g->intstat); } static void davinci_gpio_restore_context(struct davinci_gpio_controller *chips, u32 nbank) { struct davinci_gpio_regs __iomem *g; struct davinci_gpio_regs *context; u32 bank; void __iomem *base; base = chips->regs[0] - offset_array[0]; if (readl_relaxed(base + BINTEN) != chips->binten_context) writel_relaxed(chips->binten_context, base + BINTEN); for (bank = 0; bank < nbank; bank++) { g = chips->regs[bank]; context = &chips->context[bank]; if (readl_relaxed(&g->dir) != context->dir) writel_relaxed(context->dir, &g->dir); if (readl_relaxed(&g->set_data) != context->set_data) writel_relaxed(context->set_data, &g->set_data); if (readl_relaxed(&g->set_rising) != context->set_rising) writel_relaxed(context->set_rising, &g->set_rising); if (readl_relaxed(&g->set_falling) != context->set_falling) writel_relaxed(context->set_falling, &g->set_falling); } } static int davinci_gpio_suspend(struct device *dev) { struct davinci_gpio_controller *chips = dev_get_drvdata(dev); struct davinci_gpio_platform_data *pdata = dev_get_platdata(dev); u32 nbank = DIV_ROUND_UP(pdata->ngpio, 32); davinci_gpio_save_context(chips, nbank); return 0; } static int davinci_gpio_resume(struct device *dev) { struct davinci_gpio_controller *chips = dev_get_drvdata(dev); struct davinci_gpio_platform_data *pdata = dev_get_platdata(dev); u32 nbank = DIV_ROUND_UP(pdata->ngpio, 32); davinci_gpio_restore_context(chips, nbank); return 0; } static DEFINE_SIMPLE_DEV_PM_OPS(davinci_gpio_dev_pm_ops, davinci_gpio_suspend, davinci_gpio_resume); static const struct of_device_id davinci_gpio_ids[] = { { .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip}, { .compatible = "ti,am654-gpio", keystone_gpio_get_irq_chip}, { .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip}, { /* sentinel */ }, }; MODULE_DEVICE_TABLE(of, davinci_gpio_ids); static struct platform_driver davinci_gpio_driver = { .probe = davinci_gpio_probe, .driver = { .name = "davinci_gpio", .pm = pm_sleep_ptr(&davinci_gpio_dev_pm_ops), .of_match_table = of_match_ptr(davinci_gpio_ids), }, }; /* * GPIO driver registration needs to be done before machine_init functions * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall. */ static int __init davinci_gpio_drv_reg(void) { return platform_driver_register(&davinci_gpio_driver); } postcore_initcall(davinci_gpio_drv_reg); static void __exit davinci_gpio_exit(void) { platform_driver_unregister(&davinci_gpio_driver); } module_exit(davinci_gpio_exit); MODULE_AUTHOR("Jan Kotas <jank@cadence.com>"); MODULE_DESCRIPTION("DAVINCI GPIO driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:gpio-davinci");