/* * TI DaVinci GPIO Support * * Copyright (c) 2006-2007 David Brownell * Copyright (c) 2007, MontaVista Software, Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include 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; }; #define BINTEN 0x8 /* GPIO Interrupt Per-Bank Enable Register */ #define chip2controller(chip) \ container_of(chip, struct davinci_gpio_controller, chip) static void __iomem *gpio_base; static struct davinci_gpio_regs __iomem *gpio2regs(unsigned gpio) { void __iomem *ptr; if (gpio < 32 * 1) ptr = gpio_base + 0x10; else if (gpio < 32 * 2) ptr = gpio_base + 0x38; else if (gpio < 32 * 3) ptr = gpio_base + 0x60; else if (gpio < 32 * 4) ptr = gpio_base + 0x88; else if (gpio < 32 * 5) ptr = gpio_base + 0xb0; else ptr = NULL; return ptr; } static inline struct davinci_gpio_regs __iomem *irq2regs(int irq) { struct davinci_gpio_regs __iomem *g; g = (__force struct davinci_gpio_regs __iomem *)irq_get_chip_data(irq); 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 = chip2controller(chip); struct davinci_gpio_regs __iomem *g = d->regs; unsigned long flags; u32 temp; u32 mask = 1 << offset; 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 = chip2controller(chip); struct davinci_gpio_regs __iomem *g = d->regs; return (1 << 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 = chip2controller(chip); struct davinci_gpio_regs __iomem *g = d->regs; writel_relaxed((1 << 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 pdev->dev.platform_data; 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 i, base; unsigned ngpio; struct davinci_gpio_controller *chips; struct davinci_gpio_platform_data *pdata; struct davinci_gpio_regs __iomem *regs; struct device *dev = &pdev->dev; struct resource *res; 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 (WARN_ON(ARCH_NR_GPIOS < ngpio)) ngpio = ARCH_NR_GPIOS; chips = devm_kzalloc(dev, ngpio * sizeof(struct davinci_gpio_controller), GFP_KERNEL); if (!chips) { dev_err(dev, "Memory allocation failed\n"); return -ENOMEM; } res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(dev, "Invalid memory resource\n"); return -EBUSY; } gpio_base = devm_ioremap_resource(dev, res); if (IS_ERR(gpio_base)) return PTR_ERR(gpio_base); for (i = 0, base = 0; base < ngpio; i++, base += 32) { chips[i].chip.label = "DaVinci"; chips[i].chip.direction_input = davinci_direction_in; chips[i].chip.get = davinci_gpio_get; chips[i].chip.direction_output = davinci_direction_out; chips[i].chip.set = davinci_gpio_set; chips[i].chip.base = base; chips[i].chip.ngpio = ngpio - base; if (chips[i].chip.ngpio > 32) chips[i].chip.ngpio = 32; #ifdef CONFIG_OF_GPIO chips[i].chip.of_node = dev->of_node; #endif spin_lock_init(&chips[i].lock); regs = gpio2regs(base); chips[i].regs = regs; chips[i].set_data = ®s->set_data; chips[i].clr_data = ®s->clr_data; chips[i].in_data = ®s->in_data; gpiochip_add(&chips[i].chip); } platform_set_drvdata(pdev, chips); davinci_gpio_irq_setup(pdev); 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->irq); u32 mask = (u32) 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->irq); u32 mask = (u32) 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, }; static void gpio_irq_handler(unsigned irq, struct irq_desc *desc) { struct davinci_gpio_regs __iomem *g; u32 mask = 0xffff; struct davinci_gpio_controller *d; d = (struct davinci_gpio_controller *)irq_desc_get_handler_data(desc); g = (struct davinci_gpio_regs __iomem *)d->regs; /* we only care about one bank */ if (irq & 1) mask <<= 16; /* temporarily mask (level sensitive) parent IRQ */ chained_irq_enter(irq_desc_get_chip(desc), desc); while (1) { u32 status; int bit; /* 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); generic_handle_irq( irq_find_mapping(d->irq_domain, d->chip.base + bit)); } } 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 = chip2controller(chip); if (d->irq_domain) return irq_create_mapping(d->irq_domain, d->chip.base + offset); else return -ENXIO; } static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset) { struct davinci_gpio_controller *d = chip2controller(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->gpio_irq + 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; d = (struct davinci_gpio_controller *)data->handler_data; g = (struct davinci_gpio_regs __iomem *)d->regs; mask = __gpio_mask(data->irq - d->gpio_irq); 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_regs __iomem *g = gpio2regs(hw); 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 *)__gpio_mask(hw)); set_irq_flags(irq, IRQF_VALID); return 0; } static const struct irq_domain_ops davinci_gpio_irq_ops = { .map = davinci_gpio_irq_map, .xlate = irq_domain_xlate_onetwocell, }; /* * 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; struct clk *clk; u32 binten = 0; unsigned ngpio, bank_irq; struct device *dev = &pdev->dev; struct resource *res; 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; ngpio = pdata->ngpio; res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); if (!res) { dev_err(dev, "Invalid IRQ resource\n"); return -EBUSY; } bank_irq = res->start; if (!bank_irq) { dev_err(dev, "Invalid IRQ resource\n"); return -ENODEV; } clk = devm_clk_get(dev, "gpio"); if (IS_ERR(clk)) { printk(KERN_ERR "Error %ld getting gpio clock?\n", PTR_ERR(clk)); return PTR_ERR(clk); } clk_prepare_enable(clk); if (!pdata->gpio_unbanked) { irq = irq_alloc_descs(-1, 0, ngpio, 0); if (irq < 0) { dev_err(dev, "Couldn't allocate IRQ numbers\n"); return irq; } irq_domain = irq_domain_add_legacy(NULL, ngpio, irq, 0, &davinci_gpio_irq_ops, chips); if (!irq_domain) { dev_err(dev, "Couldn't register an IRQ domain\n"); return -ENODEV; } } /* * Arrange gpio_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. */ for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 32) { chips[bank].chip.to_irq = gpio_to_irq_banked; chips[bank].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) { static struct irq_chip_type gpio_unbanked; /* pass "bank 0" GPIO IRQs to AINTC */ chips[0].chip.to_irq = gpio_to_irq_unbanked; chips[0].gpio_irq = bank_irq; chips[0].gpio_unbanked = pdata->gpio_unbanked; binten = BIT(0); /* AINTC handles mask/unmask; GPIO handles triggering */ irq = bank_irq; gpio_unbanked = *container_of(irq_get_chip(irq), struct irq_chip_type, chip); gpio_unbanked.chip.name = "GPIO-AINTC"; gpio_unbanked.chip.irq_set_type = gpio_irq_type_unbanked; /* default trigger: both edges */ g = gpio2regs(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++) { irq_set_chip(irq, &gpio_unbanked.chip); irq_set_handler_data(irq, &chips[gpio / 32]); irq_set_status_flags(irq, 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++, bank_irq++, gpio += 16) { /* disabled by default, enabled only as needed */ g = gpio2regs(gpio); writel_relaxed(~0, &g->clr_falling); writel_relaxed(~0, &g->clr_rising); /* set up all irqs in this bank */ irq_set_chained_handler(bank_irq, gpio_irq_handler); /* * 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. */ irq_set_handler_data(bank_irq, &chips[gpio / 32]); 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; } #if IS_ENABLED(CONFIG_OF) static const struct of_device_id davinci_gpio_ids[] = { { .compatible = "ti,dm6441-gpio", }, { /* sentinel */ }, }; MODULE_DEVICE_TABLE(of, davinci_gpio_ids); #endif static struct platform_driver davinci_gpio_driver = { .probe = davinci_gpio_probe, .driver = { .name = "davinci_gpio", .owner = THIS_MODULE, .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);