diff options
author | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-08-06 18:13:54 +0100 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-08-06 18:13:54 +0100 |
commit | 11e4afb49b7fa1fc8e1ffd850c1806dd86a08204 (patch) | |
tree | 9e57efcb106ae912f7bec718feb3f8ec607559bb /arch/arm/plat-nomadik/gpio.c | |
parent | 162500b3a3ff39d941d29db49b41a16667ae44f0 (diff) | |
parent | 9b2a606d3898fcb2eedb6faded3bb37549590ac4 (diff) | |
download | op-kernel-dev-11e4afb49b7fa1fc8e1ffd850c1806dd86a08204.zip op-kernel-dev-11e4afb49b7fa1fc8e1ffd850c1806dd86a08204.tar.gz |
Merge branches 'gemini' and 'misc' into devel
Diffstat (limited to 'arch/arm/plat-nomadik/gpio.c')
-rw-r--r-- | arch/arm/plat-nomadik/gpio.c | 643 |
1 files changed, 643 insertions, 0 deletions
diff --git a/arch/arm/plat-nomadik/gpio.c b/arch/arm/plat-nomadik/gpio.c new file mode 100644 index 0000000..977c8f9 --- /dev/null +++ b/arch/arm/plat-nomadik/gpio.c @@ -0,0 +1,643 @@ +/* + * Generic GPIO driver for logic cells found in the Nomadik SoC + * + * Copyright (C) 2008,2009 STMicroelectronics + * Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it> + * Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/gpio.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/slab.h> + +#include <plat/pincfg.h> +#include <mach/hardware.h> +#include <mach/gpio.h> + +/* + * The GPIO module in the Nomadik family of Systems-on-Chip is an + * AMBA device, managing 32 pins and alternate functions. The logic block + * is currently only used in the Nomadik. + * + * Symbols in this file are called "nmk_gpio" for "nomadik gpio" + */ + +#define NMK_GPIO_PER_CHIP 32 +struct nmk_gpio_chip { + struct gpio_chip chip; + void __iomem *addr; + struct clk *clk; + unsigned int parent_irq; + spinlock_t lock; + /* Keep track of configured edges */ + u32 edge_rising; + u32 edge_falling; +}; + +static void __nmk_gpio_set_mode(struct nmk_gpio_chip *nmk_chip, + unsigned offset, int gpio_mode) +{ + u32 bit = 1 << offset; + u32 afunc, bfunc; + + afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & ~bit; + bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & ~bit; + if (gpio_mode & NMK_GPIO_ALT_A) + afunc |= bit; + if (gpio_mode & NMK_GPIO_ALT_B) + bfunc |= bit; + writel(afunc, nmk_chip->addr + NMK_GPIO_AFSLA); + writel(bfunc, nmk_chip->addr + NMK_GPIO_AFSLB); +} + +static void __nmk_gpio_set_slpm(struct nmk_gpio_chip *nmk_chip, + unsigned offset, enum nmk_gpio_slpm mode) +{ + u32 bit = 1 << offset; + u32 slpm; + + slpm = readl(nmk_chip->addr + NMK_GPIO_SLPC); + if (mode == NMK_GPIO_SLPM_NOCHANGE) + slpm |= bit; + else + slpm &= ~bit; + writel(slpm, nmk_chip->addr + NMK_GPIO_SLPC); +} + +static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip, + unsigned offset, enum nmk_gpio_pull pull) +{ + u32 bit = 1 << offset; + u32 pdis; + + pdis = readl(nmk_chip->addr + NMK_GPIO_PDIS); + if (pull == NMK_GPIO_PULL_NONE) + pdis |= bit; + else + pdis &= ~bit; + writel(pdis, nmk_chip->addr + NMK_GPIO_PDIS); + + if (pull == NMK_GPIO_PULL_UP) + writel(bit, nmk_chip->addr + NMK_GPIO_DATS); + else if (pull == NMK_GPIO_PULL_DOWN) + writel(bit, nmk_chip->addr + NMK_GPIO_DATC); +} + +static void __nmk_gpio_make_input(struct nmk_gpio_chip *nmk_chip, + unsigned offset) +{ + writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC); +} + +static void __nmk_config_pin(struct nmk_gpio_chip *nmk_chip, unsigned offset, + pin_cfg_t cfg) +{ + static const char *afnames[] = { + [NMK_GPIO_ALT_GPIO] = "GPIO", + [NMK_GPIO_ALT_A] = "A", + [NMK_GPIO_ALT_B] = "B", + [NMK_GPIO_ALT_C] = "C" + }; + static const char *pullnames[] = { + [NMK_GPIO_PULL_NONE] = "none", + [NMK_GPIO_PULL_UP] = "up", + [NMK_GPIO_PULL_DOWN] = "down", + [3] /* illegal */ = "??" + }; + static const char *slpmnames[] = { + [NMK_GPIO_SLPM_INPUT] = "input", + [NMK_GPIO_SLPM_NOCHANGE] = "no-change", + }; + + int pin = PIN_NUM(cfg); + int pull = PIN_PULL(cfg); + int af = PIN_ALT(cfg); + int slpm = PIN_SLPM(cfg); + + dev_dbg(nmk_chip->chip.dev, "pin %d: af %s, pull %s, slpm %s\n", + pin, afnames[af], pullnames[pull], slpmnames[slpm]); + + __nmk_gpio_make_input(nmk_chip, offset); + __nmk_gpio_set_pull(nmk_chip, offset, pull); + __nmk_gpio_set_slpm(nmk_chip, offset, slpm); + __nmk_gpio_set_mode(nmk_chip, offset, af); +} + +/** + * nmk_config_pin - configure a pin's mux attributes + * @cfg: pin confguration + * + * Configures a pin's mode (alternate function or GPIO), its pull up status, + * and its sleep mode based on the specified configuration. The @cfg is + * usually one of the SoC specific macros defined in mach/<soc>-pins.h. These + * are constructed using, and can be further enhanced with, the macros in + * plat/pincfg.h. + * + * If a pin's mode is set to GPIO, it is configured as an input to avoid + * side-effects. The gpio can be manipulated later using standard GPIO API + * calls. + */ +int nmk_config_pin(pin_cfg_t cfg) +{ + struct nmk_gpio_chip *nmk_chip; + int gpio = PIN_NUM(cfg); + unsigned long flags; + + nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio)); + if (!nmk_chip) + return -EINVAL; + + spin_lock_irqsave(&nmk_chip->lock, flags); + __nmk_config_pin(nmk_chip, gpio - nmk_chip->chip.base, cfg); + spin_unlock_irqrestore(&nmk_chip->lock, flags); + + return 0; +} +EXPORT_SYMBOL(nmk_config_pin); + +/** + * nmk_config_pins - configure several pins at once + * @cfgs: array of pin configurations + * @num: number of elments in the array + * + * Configures several pins using nmk_config_pin(). Refer to that function for + * further information. + */ +int nmk_config_pins(pin_cfg_t *cfgs, int num) +{ + int ret = 0; + int i; + + for (i = 0; i < num; i++) { + int ret = nmk_config_pin(cfgs[i]); + if (ret) + break; + } + + return ret; +} +EXPORT_SYMBOL(nmk_config_pins); + +/** + * nmk_gpio_set_slpm() - configure the sleep mode of a pin + * @gpio: pin number + * @mode: NMK_GPIO_SLPM_INPUT or NMK_GPIO_SLPM_NOCHANGE, + * + * Sets the sleep mode of a pin. If @mode is NMK_GPIO_SLPM_INPUT, the pin is + * changed to an input (with pullup/down enabled) in sleep and deep sleep. If + * @mode is NMK_GPIO_SLPM_NOCHANGE, the pin remains in the state it was + * configured even when in sleep and deep sleep. + */ +int nmk_gpio_set_slpm(int gpio, enum nmk_gpio_slpm mode) +{ + struct nmk_gpio_chip *nmk_chip; + unsigned long flags; + + nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio)); + if (!nmk_chip) + return -EINVAL; + + spin_lock_irqsave(&nmk_chip->lock, flags); + __nmk_gpio_set_slpm(nmk_chip, gpio - nmk_chip->chip.base, mode); + spin_unlock_irqrestore(&nmk_chip->lock, flags); + + return 0; +} + +/** + * nmk_gpio_set_pull() - enable/disable pull up/down on a gpio + * @gpio: pin number + * @pull: one of NMK_GPIO_PULL_DOWN, NMK_GPIO_PULL_UP, and NMK_GPIO_PULL_NONE + * + * Enables/disables pull up/down on a specified pin. This only takes effect if + * the pin is configured as an input (either explicitly or by the alternate + * function). + * + * NOTE: If enabling the pull up/down, the caller must ensure that the GPIO is + * configured as an input. Otherwise, due to the way the controller registers + * work, this function will change the value output on the pin. + */ +int nmk_gpio_set_pull(int gpio, enum nmk_gpio_pull pull) +{ + struct nmk_gpio_chip *nmk_chip; + unsigned long flags; + + nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio)); + if (!nmk_chip) + return -EINVAL; + + spin_lock_irqsave(&nmk_chip->lock, flags); + __nmk_gpio_set_pull(nmk_chip, gpio - nmk_chip->chip.base, pull); + spin_unlock_irqrestore(&nmk_chip->lock, flags); + + return 0; +} + +/* Mode functions */ +int nmk_gpio_set_mode(int gpio, int gpio_mode) +{ + struct nmk_gpio_chip *nmk_chip; + unsigned long flags; + + nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio)); + if (!nmk_chip) + return -EINVAL; + + spin_lock_irqsave(&nmk_chip->lock, flags); + __nmk_gpio_set_mode(nmk_chip, gpio - nmk_chip->chip.base, gpio_mode); + spin_unlock_irqrestore(&nmk_chip->lock, flags); + + return 0; +} +EXPORT_SYMBOL(nmk_gpio_set_mode); + +int nmk_gpio_get_mode(int gpio) +{ + struct nmk_gpio_chip *nmk_chip; + u32 afunc, bfunc, bit; + + nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio)); + if (!nmk_chip) + return -EINVAL; + + bit = 1 << (gpio - nmk_chip->chip.base); + + afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & bit; + bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & bit; + + return (afunc ? NMK_GPIO_ALT_A : 0) | (bfunc ? NMK_GPIO_ALT_B : 0); +} +EXPORT_SYMBOL(nmk_gpio_get_mode); + + +/* IRQ functions */ +static inline int nmk_gpio_get_bitmask(int gpio) +{ + return 1 << (gpio % 32); +} + +static void nmk_gpio_irq_ack(unsigned int irq) +{ + int gpio; + struct nmk_gpio_chip *nmk_chip; + + gpio = NOMADIK_IRQ_TO_GPIO(irq); + nmk_chip = get_irq_chip_data(irq); + if (!nmk_chip) + return; + writel(nmk_gpio_get_bitmask(gpio), nmk_chip->addr + NMK_GPIO_IC); +} + +enum nmk_gpio_irq_type { + NORMAL, + WAKE, +}; + +static void __nmk_gpio_irq_modify(struct nmk_gpio_chip *nmk_chip, + int gpio, enum nmk_gpio_irq_type which, + bool enable) +{ + u32 rimsc = which == WAKE ? NMK_GPIO_RWIMSC : NMK_GPIO_RIMSC; + u32 fimsc = which == WAKE ? NMK_GPIO_FWIMSC : NMK_GPIO_FIMSC; + u32 bitmask = nmk_gpio_get_bitmask(gpio); + u32 reg; + + /* we must individually set/clear the two edges */ + if (nmk_chip->edge_rising & bitmask) { + reg = readl(nmk_chip->addr + rimsc); + if (enable) + reg |= bitmask; + else + reg &= ~bitmask; + writel(reg, nmk_chip->addr + rimsc); + } + if (nmk_chip->edge_falling & bitmask) { + reg = readl(nmk_chip->addr + fimsc); + if (enable) + reg |= bitmask; + else + reg &= ~bitmask; + writel(reg, nmk_chip->addr + fimsc); + } +} + +static int nmk_gpio_irq_modify(unsigned int irq, enum nmk_gpio_irq_type which, + bool enable) +{ + int gpio; + struct nmk_gpio_chip *nmk_chip; + unsigned long flags; + u32 bitmask; + + gpio = NOMADIK_IRQ_TO_GPIO(irq); + nmk_chip = get_irq_chip_data(irq); + bitmask = nmk_gpio_get_bitmask(gpio); + if (!nmk_chip) + return -EINVAL; + + spin_lock_irqsave(&nmk_chip->lock, flags); + __nmk_gpio_irq_modify(nmk_chip, gpio, which, enable); + spin_unlock_irqrestore(&nmk_chip->lock, flags); + + return 0; +} + +static void nmk_gpio_irq_mask(unsigned int irq) +{ + nmk_gpio_irq_modify(irq, NORMAL, false); +} + +static void nmk_gpio_irq_unmask(unsigned int irq) +{ + nmk_gpio_irq_modify(irq, NORMAL, true); +} + +static int nmk_gpio_irq_set_wake(unsigned int irq, unsigned int on) +{ + return nmk_gpio_irq_modify(irq, WAKE, on); +} + +static int nmk_gpio_irq_set_type(unsigned int irq, unsigned int type) +{ + struct irq_desc *desc = irq_to_desc(irq); + bool enabled = !(desc->status & IRQ_DISABLED); + bool wake = desc->wake_depth; + int gpio; + struct nmk_gpio_chip *nmk_chip; + unsigned long flags; + u32 bitmask; + + gpio = NOMADIK_IRQ_TO_GPIO(irq); + nmk_chip = get_irq_chip_data(irq); + bitmask = nmk_gpio_get_bitmask(gpio); + if (!nmk_chip) + return -EINVAL; + + if (type & IRQ_TYPE_LEVEL_HIGH) + return -EINVAL; + if (type & IRQ_TYPE_LEVEL_LOW) + return -EINVAL; + + spin_lock_irqsave(&nmk_chip->lock, flags); + + if (enabled) + __nmk_gpio_irq_modify(nmk_chip, gpio, NORMAL, false); + + if (wake) + __nmk_gpio_irq_modify(nmk_chip, gpio, WAKE, false); + + nmk_chip->edge_rising &= ~bitmask; + if (type & IRQ_TYPE_EDGE_RISING) + nmk_chip->edge_rising |= bitmask; + + nmk_chip->edge_falling &= ~bitmask; + if (type & IRQ_TYPE_EDGE_FALLING) + nmk_chip->edge_falling |= bitmask; + + if (enabled) + __nmk_gpio_irq_modify(nmk_chip, gpio, NORMAL, true); + + if (wake) + __nmk_gpio_irq_modify(nmk_chip, gpio, WAKE, true); + + spin_unlock_irqrestore(&nmk_chip->lock, flags); + + return 0; +} + +static struct irq_chip nmk_gpio_irq_chip = { + .name = "Nomadik-GPIO", + .ack = nmk_gpio_irq_ack, + .mask = nmk_gpio_irq_mask, + .unmask = nmk_gpio_irq_unmask, + .set_type = nmk_gpio_irq_set_type, + .set_wake = nmk_gpio_irq_set_wake, +}; + +static void nmk_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) +{ + struct nmk_gpio_chip *nmk_chip; + struct irq_chip *host_chip = get_irq_chip(irq); + unsigned int gpio_irq; + u32 pending; + unsigned int first_irq; + + if (host_chip->mask_ack) + host_chip->mask_ack(irq); + else { + host_chip->mask(irq); + if (host_chip->ack) + host_chip->ack(irq); + } + + nmk_chip = get_irq_data(irq); + first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base); + while ( (pending = readl(nmk_chip->addr + NMK_GPIO_IS)) ) { + gpio_irq = first_irq + __ffs(pending); + generic_handle_irq(gpio_irq); + } + + host_chip->unmask(irq); +} + +static int nmk_gpio_init_irq(struct nmk_gpio_chip *nmk_chip) +{ + unsigned int first_irq; + int i; + + first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base); + for (i = first_irq; i < first_irq + NMK_GPIO_PER_CHIP; i++) { + set_irq_chip(i, &nmk_gpio_irq_chip); + set_irq_handler(i, handle_edge_irq); + set_irq_flags(i, IRQF_VALID); + set_irq_chip_data(i, nmk_chip); + set_irq_type(i, IRQ_TYPE_EDGE_FALLING); + } + set_irq_chained_handler(nmk_chip->parent_irq, nmk_gpio_irq_handler); + set_irq_data(nmk_chip->parent_irq, nmk_chip); + return 0; +} + +/* I/O Functions */ +static int nmk_gpio_make_input(struct gpio_chip *chip, unsigned offset) +{ + struct nmk_gpio_chip *nmk_chip = + container_of(chip, struct nmk_gpio_chip, chip); + + writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC); + return 0; +} + +static int nmk_gpio_get_input(struct gpio_chip *chip, unsigned offset) +{ + struct nmk_gpio_chip *nmk_chip = + container_of(chip, struct nmk_gpio_chip, chip); + u32 bit = 1 << offset; + + return (readl(nmk_chip->addr + NMK_GPIO_DAT) & bit) != 0; +} + +static void nmk_gpio_set_output(struct gpio_chip *chip, unsigned offset, + int val) +{ + struct nmk_gpio_chip *nmk_chip = + container_of(chip, struct nmk_gpio_chip, chip); + u32 bit = 1 << offset; + + if (val) + writel(bit, nmk_chip->addr + NMK_GPIO_DATS); + else + writel(bit, nmk_chip->addr + NMK_GPIO_DATC); +} + +static int nmk_gpio_make_output(struct gpio_chip *chip, unsigned offset, + int val) +{ + struct nmk_gpio_chip *nmk_chip = + container_of(chip, struct nmk_gpio_chip, chip); + + writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRS); + nmk_gpio_set_output(chip, offset, val); + + return 0; +} + +static int nmk_gpio_to_irq(struct gpio_chip *chip, unsigned offset) +{ + struct nmk_gpio_chip *nmk_chip = + container_of(chip, struct nmk_gpio_chip, chip); + + return NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base) + offset; +} + +/* This structure is replicated for each GPIO block allocated at probe time */ +static struct gpio_chip nmk_gpio_template = { + .direction_input = nmk_gpio_make_input, + .get = nmk_gpio_get_input, + .direction_output = nmk_gpio_make_output, + .set = nmk_gpio_set_output, + .to_irq = nmk_gpio_to_irq, + .ngpio = NMK_GPIO_PER_CHIP, + .can_sleep = 0, +}; + +static int __init nmk_gpio_probe(struct platform_device *dev) +{ + struct nmk_gpio_platform_data *pdata = dev->dev.platform_data; + struct nmk_gpio_chip *nmk_chip; + struct gpio_chip *chip; + struct resource *res; + struct clk *clk; + int irq; + int ret; + + if (!pdata) + return -ENODEV; + + res = platform_get_resource(dev, IORESOURCE_MEM, 0); + if (!res) { + ret = -ENOENT; + goto out; + } + + irq = platform_get_irq(dev, 0); + if (irq < 0) { + ret = irq; + goto out; + } + + if (request_mem_region(res->start, resource_size(res), + dev_name(&dev->dev)) == NULL) { + ret = -EBUSY; + goto out; + } + + clk = clk_get(&dev->dev, NULL); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + goto out_release; + } + + clk_enable(clk); + + nmk_chip = kzalloc(sizeof(*nmk_chip), GFP_KERNEL); + if (!nmk_chip) { + ret = -ENOMEM; + goto out_clk; + } + /* + * The virt address in nmk_chip->addr is in the nomadik register space, + * so we can simply convert the resource address, without remapping + */ + nmk_chip->clk = clk; + nmk_chip->addr = io_p2v(res->start); + nmk_chip->chip = nmk_gpio_template; + nmk_chip->parent_irq = irq; + spin_lock_init(&nmk_chip->lock); + + chip = &nmk_chip->chip; + chip->base = pdata->first_gpio; + chip->label = pdata->name; + chip->dev = &dev->dev; + chip->owner = THIS_MODULE; + + ret = gpiochip_add(&nmk_chip->chip); + if (ret) + goto out_free; + + platform_set_drvdata(dev, nmk_chip); + + nmk_gpio_init_irq(nmk_chip); + + dev_info(&dev->dev, "Bits %i-%i at address %p\n", + nmk_chip->chip.base, nmk_chip->chip.base+31, nmk_chip->addr); + return 0; + +out_free: + kfree(nmk_chip); +out_clk: + clk_disable(clk); + clk_put(clk); +out_release: + release_mem_region(res->start, resource_size(res)); +out: + dev_err(&dev->dev, "Failure %i for GPIO %i-%i\n", ret, + pdata->first_gpio, pdata->first_gpio+31); + return ret; +} + +static struct platform_driver nmk_gpio_driver = { + .driver = { + .owner = THIS_MODULE, + .name = "gpio", + }, + .probe = nmk_gpio_probe, + .suspend = NULL, /* to be done */ + .resume = NULL, +}; + +static int __init nmk_gpio_init(void) +{ + return platform_driver_register(&nmk_gpio_driver); +} + +core_initcall(nmk_gpio_init); + +MODULE_AUTHOR("Prafulla WADASKAR and Alessandro Rubini"); +MODULE_DESCRIPTION("Nomadik GPIO Driver"); +MODULE_LICENSE("GPL"); + + |