summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/gpio/gpio-davinci.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/drivers/gpio/gpio-davinci.c')
-rw-r--r--kernel/drivers/gpio/gpio-davinci.c629
1 files changed, 629 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpio-davinci.c b/kernel/drivers/gpio/gpio-davinci.c
new file mode 100644
index 000000000..c5e05c82d
--- /dev/null
+++ b/kernel/drivers/gpio/gpio-davinci.c
@@ -0,0 +1,629 @@
+/*
+ * TI DaVinci GPIO Support
+ *
+ * Copyright (c) 2006-2007 David Brownell
+ * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
+ *
+ * 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 <linux/gpio.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/platform_device.h>
+#include <linux/platform_data/gpio-davinci.h>
+#include <linux/irqchip/chained_irq.h>
+
+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 */
+
+#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;
+}
+
+#ifdef CONFIG_OF_GPIO
+static int davinci_gpio_of_xlate(struct gpio_chip *gc,
+ const struct of_phandle_args *gpiospec,
+ u32 *flags)
+{
+ struct davinci_gpio_controller *chips = dev_get_drvdata(gc->dev);
+ struct davinci_gpio_platform_data *pdata = dev_get_platdata(gc->dev);
+
+ if (gpiospec->args[0] > pdata->ngpio)
+ return -EINVAL;
+
+ if (gc != &chips[gpiospec->args[0] / 32].chip)
+ return -EINVAL;
+
+ if (flags)
+ *flags = gpiospec->args[1];
+
+ return gpiospec->args[0] % 32;
+}
+#endif
+
+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)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ 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_gpio_n_cells = 2;
+ chips[i].chip.of_xlate = davinci_gpio_of_xlate;
+ chips[i].chip.dev = dev;
+ 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 = &regs->set_data;
+ chips[i].clr_data = &regs->clr_data;
+ chips[i].in_data = &regs->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,
+};
+
+static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
+{
+ static struct irq_chip_type gpio_unbanked;
+
+ gpio_unbanked = *container_of(irq_get_chip(irq),
+ struct irq_chip_type, chip);
+
+ 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;
+ 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;
+ const struct of_device_id *match;
+ struct irq_chip *irq_chip;
+ 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;
+ 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) {
+ /* 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;
+ 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 = 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, irq_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,keystone-gpio", keystone_gpio_get_irq_chip},
+ { .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip},
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
+#endif
+
+static struct platform_driver davinci_gpio_driver = {
+ .probe = davinci_gpio_probe,
+ .driver = {
+ .name = "davinci_gpio",
+ .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);