diff options
Diffstat (limited to 'arch/arm/plat-nomadik/gpio.c')
| -rw-r--r-- | arch/arm/plat-nomadik/gpio.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/arch/arm/plat-nomadik/gpio.c b/arch/arm/plat-nomadik/gpio.c index 7b7393f96a9c..465ae5bc00b1 100644 --- a/arch/arm/plat-nomadik/gpio.c +++ b/arch/arm/plat-nomadik/gpio.c @@ -23,6 +23,7 @@ #include <linux/irq.h> #include <linux/slab.h> +#include <plat/pincfg.h> #include <mach/hardware.h> #include <mach/gpio.h> @@ -95,6 +96,101 @@ static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip, 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 |