diff options
Diffstat (limited to 'drivers/gpio/gpio-tegra.c')
| -rw-r--r-- | drivers/gpio/gpio-tegra.c | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-tegra.c b/drivers/gpio/gpio-tegra.c new file mode 100644 index 000000000000..747eb40e8afe --- /dev/null +++ b/drivers/gpio/gpio-tegra.c @@ -0,0 +1,441 @@ +/* + * 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/init.h> +#include <linux/irq.h> +#include <linux/interrupt.h> + +#include <linux/io.h> +#include <linux/gpio.h> +#include <linux/of.h> + +#include <asm/mach/irq.h> + +#include <mach/iomap.h> +#include <mach/suspend.h> + +#define GPIO_BANK(x) ((x) >> 5) +#define GPIO_PORT(x) (((x) >> 3) & 0x3) +#define GPIO_BIT(x) ((x) & 0x7) + +#define GPIO_REG(x) (IO_TO_VIRT(TEGRA_GPIO_BASE) + \ + GPIO_BANK(x) * 0x80 + \ + 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) + 0x800) +#define GPIO_MSK_OE(x) (GPIO_REG(x) + 0x810) +#define GPIO_MSK_OUT(x) (GPIO_REG(x) + 0X820) +#define GPIO_MSK_INT_STA(x) (GPIO_REG(x) + 0x840) +#define GPIO_MSK_INT_ENB(x) (GPIO_REG(x) + 0x850) +#define GPIO_MSK_INT_LVL(x) (GPIO_REG(x) + 0x860) + +#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 + u32 cnf[4]; + u32 out[4]; + u32 oe[4]; + u32 int_enb[4]; + u32 int_lvl[4]; +#endif +}; + + +static struct tegra_gpio_bank tegra_gpio_banks[] = { + {.bank = 0, .irq = INT_GPIO1}, + {.bank = 1, .irq = INT_GPIO2}, + {.bank = 2, .irq = INT_GPIO3}, + {.bank = 3, .irq = INT_GPIO4}, + {.bank = 4, .irq = INT_GPIO5}, + {.bank = 5, .irq = INT_GPIO6}, + {.bank = 6, .irq = INT_GPIO7}, +}; + +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); + __raw_writel(val, reg); +} + +void tegra_gpio_enable(int gpio) +{ + tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 1); +} + +void tegra_gpio_disable(int gpio) +{ + tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 0); +} + +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) +{ + return (__raw_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); + 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); + return 0; +} + + + +static struct gpio_chip tegra_gpio_chip = { + .label = "tegra-gpio", + .direction_input = tegra_gpio_direction_input, + .get = tegra_gpio_get, + .direction_output = tegra_gpio_direction_output, + .set = tegra_gpio_set, + .base = 0, + .ngpio = TEGRA_NR_GPIOS, +}; + +static void tegra_gpio_irq_ack(struct irq_data *d) +{ + int gpio = d->irq - INT_GPIO_BASE; + + __raw_writel(1 << GPIO_BIT(gpio), GPIO_INT_CLR(gpio)); +} + +static void tegra_gpio_irq_mask(struct irq_data *d) +{ + int gpio = d->irq - INT_GPIO_BASE; + + tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 0); +} + +static void tegra_gpio_irq_unmask(struct irq_data *d) +{ + int gpio = d->irq - INT_GPIO_BASE; + + 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->irq - INT_GPIO_BASE; + 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; + + 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; + } + + spin_lock_irqsave(&bank->lvl_lock[port], flags); + + val = __raw_readl(GPIO_INT_LVL(gpio)); + val &= ~(GPIO_INT_LVL_MASK << GPIO_BIT(gpio)); + val |= lvl_type << GPIO_BIT(gpio); + __raw_writel(val, GPIO_INT_LVL(gpio)); + + spin_unlock_irqrestore(&bank->lvl_lock[port], flags); + + 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_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 = __raw_readl(GPIO_INT_STA(gpio)) & + __raw_readl(GPIO_INT_ENB(gpio)); + u32 lvl = __raw_readl(GPIO_INT_LVL(gpio)); + + for_each_set_bit(pin, &sta, 8) { + __raw_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 +void tegra_gpio_resume(void) +{ + unsigned long flags; + int b; + int p; + + local_irq_save(flags); + + for (b = 0; b < ARRAY_SIZE(tegra_gpio_banks); 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); + __raw_writel(bank->cnf[p], GPIO_CNF(gpio)); + __raw_writel(bank->out[p], GPIO_OUT(gpio)); + __raw_writel(bank->oe[p], GPIO_OE(gpio)); + __raw_writel(bank->int_lvl[p], GPIO_INT_LVL(gpio)); + __raw_writel(bank->int_enb[p], GPIO_INT_ENB(gpio)); + } + } + + local_irq_restore(flags); +} + +void tegra_gpio_suspend(void) +{ + unsigned long flags; + int b; + int p; + + local_irq_save(flags); + for (b = 0; b < ARRAY_SIZE(tegra_gpio_banks); 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] = __raw_readl(GPIO_CNF(gpio)); + bank->out[p] = __raw_readl(GPIO_OUT(gpio)); + bank->oe[p] = __raw_readl(GPIO_OE(gpio)); + bank->int_enb[p] = __raw_readl(GPIO_INT_ENB(gpio)); + bank->int_lvl[p] = __raw_readl(GPIO_INT_LVL(gpio)); + } + } + local_irq_restore(flags); +} + +static int tegra_gpio_wake_enable(struct irq_data *d, unsigned int enable) +{ + struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d); + 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, +#ifdef CONFIG_PM + .irq_set_wake = tegra_gpio_wake_enable, +#endif +}; + + +/* 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 __init tegra_gpio_init(void) +{ + struct tegra_gpio_bank *bank; + int i; + int j; + + for (i = 0; i < 7; i++) { + for (j = 0; j < 4; j++) { + int gpio = tegra_gpio_compose(i, j, 0); + __raw_writel(0x00, GPIO_INT_ENB(gpio)); + } + } + +#ifdef CONFIG_OF_GPIO + /* + * This isn't ideal, but it gets things hooked up until this + * driver is converted into a platform_device + */ + tegra_gpio_chip.of_node = of_find_compatible_node(NULL, NULL, + "nvidia,tegra20-gpio"); +#endif /* CONFIG_OF_GPIO */ + + gpiochip_add(&tegra_gpio_chip); + + for (i = INT_GPIO_BASE; i < (INT_GPIO_BASE + TEGRA_NR_GPIOS); i++) { + bank = &tegra_gpio_banks[GPIO_BANK(irq_to_gpio(i))]; + + irq_set_lockdep_class(i, &gpio_lock_class); + irq_set_chip_data(i, bank); + irq_set_chip_and_handler(i, &tegra_gpio_irq_chip, + handle_simple_irq); + set_irq_flags(i, IRQF_VALID); + } + + for (i = 0; i < ARRAY_SIZE(tegra_gpio_banks); 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; +} + +postcore_initcall(tegra_gpio_init); + +void __init tegra_gpio_config(struct tegra_gpio_table *table, int num) +{ + int i; + + for (i = 0; i < num; i++) { + int gpio = table[i].gpio; + + if (table[i].enable) + tegra_gpio_enable(gpio); + else + tegra_gpio_disable(gpio); + } +} + +#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 < 7; 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, + __raw_readl(GPIO_CNF(gpio)), + __raw_readl(GPIO_OE(gpio)), + __raw_readl(GPIO_OUT(gpio)), + __raw_readl(GPIO_IN(gpio)), + __raw_readl(GPIO_INT_STA(gpio)), + __raw_readl(GPIO_INT_ENB(gpio)), + __raw_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 |