diff options
Diffstat (limited to 'drivers/gpio/gpio-tegra.c')
| -rw-r--r-- | drivers/gpio/gpio-tegra.c | 590 |
1 files changed, 590 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-tegra.c b/drivers/gpio/gpio-tegra.c new file mode 100644 index 000000000..1741981d5 --- /dev/null +++ b/drivers/gpio/gpio-tegra.c @@ -0,0 +1,590 @@ +/* + * arch/arm/mach-tegra/gpio.c + * + * Copyright (c) 2010 Google, Inc + * + * Author: + * Erik Gilling <konkers@google.com> + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <linux/err.h> +#include <linux/init.h> +#include <linux/irq.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/gpio.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/irqdomain.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/pinctrl/consumer.h> +#include <linux/pm.h> + +#define GPIO_BANK(x) ((x) >> 5) +#define GPIO_PORT(x) (((x) >> 3) & 0x3) +#define GPIO_BIT(x) ((x) & 0x7) + +#define GPIO_REG(x) (GPIO_BANK(x) * tegra_gpio_bank_stride + \ + GPIO_PORT(x) * 4) + +#define GPIO_CNF(x) (GPIO_REG(x) + 0x00) +#define GPIO_OE(x) (GPIO_REG(x) + 0x10) +#define GPIO_OUT(x) (GPIO_REG(x) + 0X20) +#define GPIO_IN(x) (GPIO_REG(x) + 0x30) +#define GPIO_INT_STA(x) (GPIO_REG(x) + 0x40) +#define GPIO_INT_ENB(x) (GPIO_REG(x) + 0x50) +#define GPIO_INT_LVL(x) (GPIO_REG(x) + 0x60) +#define GPIO_INT_CLR(x) (GPIO_REG(x) + 0x70) + +#define GPIO_MSK_CNF(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x00) +#define GPIO_MSK_OE(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x10) +#define GPIO_MSK_OUT(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0X20) +#define GPIO_MSK_INT_STA(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x40) +#define GPIO_MSK_INT_ENB(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x50) +#define GPIO_MSK_INT_LVL(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x60) + +#define GPIO_INT_LVL_MASK 0x010101 +#define GPIO_INT_LVL_EDGE_RISING 0x000101 +#define GPIO_INT_LVL_EDGE_FALLING 0x000100 +#define GPIO_INT_LVL_EDGE_BOTH 0x010100 +#define GPIO_INT_LVL_LEVEL_HIGH 0x000001 +#define GPIO_INT_LVL_LEVEL_LOW 0x000000 + +struct tegra_gpio_bank { + int bank; + int irq; + spinlock_t lvl_lock[4]; +#ifdef CONFIG_PM_SLEEP + u32 cnf[4]; + u32 out[4]; + u32 oe[4]; + u32 int_enb[4]; + u32 int_lvl[4]; + u32 wake_enb[4]; +#endif +}; + +static struct device *dev; +static struct irq_domain *irq_domain; +static void __iomem *regs; +static u32 tegra_gpio_bank_count; +static u32 tegra_gpio_bank_stride; +static u32 tegra_gpio_upper_offset; +static struct tegra_gpio_bank *tegra_gpio_banks; + +static inline void tegra_gpio_writel(u32 val, u32 reg) +{ + __raw_writel(val, regs + reg); +} + +static inline u32 tegra_gpio_readl(u32 reg) +{ + return __raw_readl(regs + reg); +} + +static int tegra_gpio_compose(int bank, int port, int bit) +{ + return (bank << 5) | ((port & 0x3) << 3) | (bit & 0x7); +} + +static void tegra_gpio_mask_write(u32 reg, int gpio, int value) +{ + u32 val; + + val = 0x100 << GPIO_BIT(gpio); + if (value) + val |= 1 << GPIO_BIT(gpio); + tegra_gpio_writel(val, reg); +} + +static void tegra_gpio_enable(int gpio) +{ + tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 1); +} + +static void tegra_gpio_disable(int gpio) +{ + tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 0); +} + +static int tegra_gpio_request(struct gpio_chip *chip, unsigned offset) +{ + return pinctrl_request_gpio(offset); +} + +static void tegra_gpio_free(struct gpio_chip *chip, unsigned offset) +{ + pinctrl_free_gpio(offset); + tegra_gpio_disable(offset); +} + +static void tegra_gpio_set(struct gpio_chip *chip, unsigned offset, int value) +{ + tegra_gpio_mask_write(GPIO_MSK_OUT(offset), offset, value); +} + +static int tegra_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + /* If gpio is in output mode then read from the out value */ + if ((tegra_gpio_readl(GPIO_OE(offset)) >> GPIO_BIT(offset)) & 1) + return (tegra_gpio_readl(GPIO_OUT(offset)) >> + GPIO_BIT(offset)) & 0x1; + + return (tegra_gpio_readl(GPIO_IN(offset)) >> GPIO_BIT(offset)) & 0x1; +} + +static int tegra_gpio_direction_input(struct gpio_chip *chip, unsigned offset) +{ + tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 0); + tegra_gpio_enable(offset); + return 0; +} + +static int tegra_gpio_direction_output(struct gpio_chip *chip, unsigned offset, + int value) +{ + tegra_gpio_set(chip, offset, value); + tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 1); + tegra_gpio_enable(offset); + return 0; +} + +static int tegra_gpio_to_irq(struct gpio_chip *chip, unsigned offset) +{ + return irq_find_mapping(irq_domain, offset); +} + +static struct gpio_chip tegra_gpio_chip = { + .label = "tegra-gpio", + .request = tegra_gpio_request, + .free = tegra_gpio_free, + .direction_input = tegra_gpio_direction_input, + .get = tegra_gpio_get, + .direction_output = tegra_gpio_direction_output, + .set = tegra_gpio_set, + .to_irq = tegra_gpio_to_irq, + .base = 0, +}; + +static void tegra_gpio_irq_ack(struct irq_data *d) +{ + int gpio = d->hwirq; + + tegra_gpio_writel(1 << GPIO_BIT(gpio), GPIO_INT_CLR(gpio)); +} + +static void tegra_gpio_irq_mask(struct irq_data *d) +{ + int gpio = d->hwirq; + + tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 0); +} + +static void tegra_gpio_irq_unmask(struct irq_data *d) +{ + int gpio = d->hwirq; + + tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 1); +} + +static int tegra_gpio_irq_set_type(struct irq_data *d, unsigned int type) +{ + int gpio = d->hwirq; + struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d); + int port = GPIO_PORT(gpio); + int lvl_type; + int val; + unsigned long flags; + int ret; + + switch (type & IRQ_TYPE_SENSE_MASK) { + case IRQ_TYPE_EDGE_RISING: + lvl_type = GPIO_INT_LVL_EDGE_RISING; + break; + + case IRQ_TYPE_EDGE_FALLING: + lvl_type = GPIO_INT_LVL_EDGE_FALLING; + break; + + case IRQ_TYPE_EDGE_BOTH: + lvl_type = GPIO_INT_LVL_EDGE_BOTH; + break; + + case IRQ_TYPE_LEVEL_HIGH: + lvl_type = GPIO_INT_LVL_LEVEL_HIGH; + break; + + case IRQ_TYPE_LEVEL_LOW: + lvl_type = GPIO_INT_LVL_LEVEL_LOW; + break; + + default: + return -EINVAL; + } + + ret = gpiochip_lock_as_irq(&tegra_gpio_chip, gpio); + if (ret) { + dev_err(dev, "unable to lock Tegra GPIO %d as IRQ\n", gpio); + return ret; + } + + spin_lock_irqsave(&bank->lvl_lock[port], flags); + + val = tegra_gpio_readl(GPIO_INT_LVL(gpio)); + val &= ~(GPIO_INT_LVL_MASK << GPIO_BIT(gpio)); + val |= lvl_type << GPIO_BIT(gpio); + tegra_gpio_writel(val, GPIO_INT_LVL(gpio)); + + spin_unlock_irqrestore(&bank->lvl_lock[port], flags); + + tegra_gpio_mask_write(GPIO_MSK_OE(gpio), gpio, 0); + tegra_gpio_enable(gpio); + + if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) + __irq_set_handler_locked(d->irq, handle_level_irq); + else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)) + __irq_set_handler_locked(d->irq, handle_edge_irq); + + return 0; +} + +static void tegra_gpio_irq_shutdown(struct irq_data *d) +{ + int gpio = d->hwirq; + + gpiochip_unlock_as_irq(&tegra_gpio_chip, gpio); +} + +static void tegra_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) +{ + struct tegra_gpio_bank *bank; + int port; + int pin; + int unmasked = 0; + struct irq_chip *chip = irq_desc_get_chip(desc); + + chained_irq_enter(chip, desc); + + bank = irq_get_handler_data(irq); + + for (port = 0; port < 4; port++) { + int gpio = tegra_gpio_compose(bank->bank, port, 0); + unsigned long sta = tegra_gpio_readl(GPIO_INT_STA(gpio)) & + tegra_gpio_readl(GPIO_INT_ENB(gpio)); + u32 lvl = tegra_gpio_readl(GPIO_INT_LVL(gpio)); + + for_each_set_bit(pin, &sta, 8) { + tegra_gpio_writel(1 << pin, GPIO_INT_CLR(gpio)); + + /* if gpio is edge triggered, clear condition + * before executing the hander so that we don't + * miss edges + */ + if (lvl & (0x100 << pin)) { + unmasked = 1; + chained_irq_exit(chip, desc); + } + + generic_handle_irq(gpio_to_irq(gpio + pin)); + } + } + + if (!unmasked) + chained_irq_exit(chip, desc); + +} + +#ifdef CONFIG_PM_SLEEP +static int tegra_gpio_resume(struct device *dev) +{ + unsigned long flags; + int b; + int p; + + local_irq_save(flags); + + for (b = 0; b < tegra_gpio_bank_count; b++) { + struct tegra_gpio_bank *bank = &tegra_gpio_banks[b]; + + for (p = 0; p < ARRAY_SIZE(bank->oe); p++) { + unsigned int gpio = (b<<5) | (p<<3); + tegra_gpio_writel(bank->cnf[p], GPIO_CNF(gpio)); + tegra_gpio_writel(bank->out[p], GPIO_OUT(gpio)); + tegra_gpio_writel(bank->oe[p], GPIO_OE(gpio)); + tegra_gpio_writel(bank->int_lvl[p], GPIO_INT_LVL(gpio)); + tegra_gpio_writel(bank->int_enb[p], GPIO_INT_ENB(gpio)); + } + } + + local_irq_restore(flags); + return 0; +} + +static int tegra_gpio_suspend(struct device *dev) +{ + unsigned long flags; + int b; + int p; + + local_irq_save(flags); + for (b = 0; b < tegra_gpio_bank_count; b++) { + struct tegra_gpio_bank *bank = &tegra_gpio_banks[b]; + + for (p = 0; p < ARRAY_SIZE(bank->oe); p++) { + unsigned int gpio = (b<<5) | (p<<3); + bank->cnf[p] = tegra_gpio_readl(GPIO_CNF(gpio)); + bank->out[p] = tegra_gpio_readl(GPIO_OUT(gpio)); + bank->oe[p] = tegra_gpio_readl(GPIO_OE(gpio)); + bank->int_enb[p] = tegra_gpio_readl(GPIO_INT_ENB(gpio)); + bank->int_lvl[p] = tegra_gpio_readl(GPIO_INT_LVL(gpio)); + + /* Enable gpio irq for wake up source */ + tegra_gpio_writel(bank->wake_enb[p], + GPIO_INT_ENB(gpio)); + } + } + local_irq_restore(flags); + return 0; +} + +static int tegra_gpio_irq_set_wake(struct irq_data *d, unsigned int enable) +{ + struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d); + int gpio = d->hwirq; + u32 port, bit, mask; + + port = GPIO_PORT(gpio); + bit = GPIO_BIT(gpio); + mask = BIT(bit); + + if (enable) + bank->wake_enb[port] |= mask; + else + bank->wake_enb[port] &= ~mask; + + return irq_set_irq_wake(bank->irq, enable); +} +#endif + +static struct irq_chip tegra_gpio_irq_chip = { + .name = "GPIO", + .irq_ack = tegra_gpio_irq_ack, + .irq_mask = tegra_gpio_irq_mask, + .irq_unmask = tegra_gpio_irq_unmask, + .irq_set_type = tegra_gpio_irq_set_type, + .irq_shutdown = tegra_gpio_irq_shutdown, +#ifdef CONFIG_PM_SLEEP + .irq_set_wake = tegra_gpio_irq_set_wake, +#endif +}; + +static const struct dev_pm_ops tegra_gpio_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(tegra_gpio_suspend, tegra_gpio_resume) +}; + +struct tegra_gpio_soc_config { + u32 bank_stride; + u32 upper_offset; +}; + +static struct tegra_gpio_soc_config tegra20_gpio_config = { + .bank_stride = 0x80, + .upper_offset = 0x800, +}; + +static struct tegra_gpio_soc_config tegra30_gpio_config = { + .bank_stride = 0x100, + .upper_offset = 0x80, +}; + +static const struct of_device_id tegra_gpio_of_match[] = { + { .compatible = "nvidia,tegra30-gpio", .data = &tegra30_gpio_config }, + { .compatible = "nvidia,tegra20-gpio", .data = &tegra20_gpio_config }, + { }, +}; + +/* This lock class tells lockdep that GPIO irqs are in a different + * category than their parents, so it won't report false recursion. + */ +static struct lock_class_key gpio_lock_class; + +static int tegra_gpio_probe(struct platform_device *pdev) +{ + const struct of_device_id *match; + struct tegra_gpio_soc_config *config; + struct resource *res; + struct tegra_gpio_bank *bank; + int ret; + int gpio; + int i; + int j; + + dev = &pdev->dev; + + match = of_match_device(tegra_gpio_of_match, &pdev->dev); + if (!match) { + dev_err(&pdev->dev, "Error: No device match found\n"); + return -ENODEV; + } + config = (struct tegra_gpio_soc_config *)match->data; + + tegra_gpio_bank_stride = config->bank_stride; + tegra_gpio_upper_offset = config->upper_offset; + + for (;;) { + res = platform_get_resource(pdev, IORESOURCE_IRQ, tegra_gpio_bank_count); + if (!res) + break; + tegra_gpio_bank_count++; + } + if (!tegra_gpio_bank_count) { + dev_err(&pdev->dev, "Missing IRQ resource\n"); + return -ENODEV; + } + + tegra_gpio_chip.ngpio = tegra_gpio_bank_count * 32; + + tegra_gpio_banks = devm_kzalloc(&pdev->dev, + tegra_gpio_bank_count * sizeof(*tegra_gpio_banks), + GFP_KERNEL); + if (!tegra_gpio_banks) + return -ENODEV; + + irq_domain = irq_domain_add_linear(pdev->dev.of_node, + tegra_gpio_chip.ngpio, + &irq_domain_simple_ops, NULL); + if (!irq_domain) + return -ENODEV; + + for (i = 0; i < tegra_gpio_bank_count; i++) { + res = platform_get_resource(pdev, IORESOURCE_IRQ, i); + if (!res) { + dev_err(&pdev->dev, "Missing IRQ resource\n"); + return -ENODEV; + } + + bank = &tegra_gpio_banks[i]; + bank->bank = i; + bank->irq = res->start; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(regs)) + return PTR_ERR(regs); + + for (i = 0; i < tegra_gpio_bank_count; i++) { + for (j = 0; j < 4; j++) { + int gpio = tegra_gpio_compose(i, j, 0); + tegra_gpio_writel(0x00, GPIO_INT_ENB(gpio)); + } + } + + tegra_gpio_chip.of_node = pdev->dev.of_node; + + ret = gpiochip_add(&tegra_gpio_chip); + if (ret < 0) { + irq_domain_remove(irq_domain); + return ret; + } + + for (gpio = 0; gpio < tegra_gpio_chip.ngpio; gpio++) { + int irq = irq_create_mapping(irq_domain, gpio); + /* No validity check; all Tegra GPIOs are valid IRQs */ + + bank = &tegra_gpio_banks[GPIO_BANK(gpio)]; + + irq_set_lockdep_class(irq, &gpio_lock_class); + irq_set_chip_data(irq, bank); + irq_set_chip_and_handler(irq, &tegra_gpio_irq_chip, + handle_simple_irq); + set_irq_flags(irq, IRQF_VALID); + } + + for (i = 0; i < tegra_gpio_bank_count; i++) { + bank = &tegra_gpio_banks[i]; + + irq_set_chained_handler(bank->irq, tegra_gpio_irq_handler); + irq_set_handler_data(bank->irq, bank); + + for (j = 0; j < 4; j++) + spin_lock_init(&bank->lvl_lock[j]); + } + + return 0; +} + +static struct platform_driver tegra_gpio_driver = { + .driver = { + .name = "tegra-gpio", + .pm = &tegra_gpio_pm_ops, + .of_match_table = tegra_gpio_of_match, + }, + .probe = tegra_gpio_probe, +}; + +static int __init tegra_gpio_init(void) +{ + return platform_driver_register(&tegra_gpio_driver); +} +postcore_initcall(tegra_gpio_init); + +#ifdef CONFIG_DEBUG_FS + +#include <linux/debugfs.h> +#include <linux/seq_file.h> + +static int dbg_gpio_show(struct seq_file *s, void *unused) +{ + int i; + int j; + + for (i = 0; i < tegra_gpio_bank_count; i++) { + for (j = 0; j < 4; j++) { + int gpio = tegra_gpio_compose(i, j, 0); + seq_printf(s, + "%d:%d %02x %02x %02x %02x %02x %02x %06x\n", + i, j, + tegra_gpio_readl(GPIO_CNF(gpio)), + tegra_gpio_readl(GPIO_OE(gpio)), + tegra_gpio_readl(GPIO_OUT(gpio)), + tegra_gpio_readl(GPIO_IN(gpio)), + tegra_gpio_readl(GPIO_INT_STA(gpio)), + tegra_gpio_readl(GPIO_INT_ENB(gpio)), + tegra_gpio_readl(GPIO_INT_LVL(gpio))); + } + } + return 0; +} + +static int dbg_gpio_open(struct inode *inode, struct file *file) +{ + return single_open(file, dbg_gpio_show, &inode->i_private); +} + +static const struct file_operations debug_fops = { + .open = dbg_gpio_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static int __init tegra_gpio_debuginit(void) +{ + (void) debugfs_create_file("tegra_gpio", S_IRUGO, + NULL, NULL, &debug_fops); + return 0; +} +late_initcall(tegra_gpio_debuginit); +#endif |