From: Stephen Warren swarren@nvidia.com
The HW-defined procedure for booting Tegra requires that some pins be set up as GPIOs immediately at boot in order to avoid glitches on those pins, when the pinmux is programmed. Add a feature to the GPIO driver which executes a GPIO configuration table. Board files will use this to implement the correct HW initialization procedure.
Signed-off-by: Stephen Warren swarren@nvidia.com --- arch/arm/include/asm/arch-tegra/gpio.h | 20 ++++++++++++++++++++ drivers/gpio/tegra_gpio.c | 20 ++++++++++++++++++++ 2 files changed, 40 insertions(+)
diff --git a/arch/arm/include/asm/arch-tegra/gpio.h b/arch/arm/include/asm/arch-tegra/gpio.h index d97190dd7cf5..44cd455699e7 100644 --- a/arch/arm/include/asm/arch-tegra/gpio.h +++ b/arch/arm/include/asm/arch-tegra/gpio.h @@ -14,11 +14,31 @@ #define GPIO_FULLPORT(x) ((x) >> 3) #define GPIO_BIT(x) ((x) & 0x7)
+enum tegra_gpio_init { + TEGRA_GPIO_INIT_IN, + TEGRA_GPIO_INIT_OUT0, + TEGRA_GPIO_INIT_OUT1, +}; + +struct tegra_gpio_config { + u32 gpio:16; + u32 init:2; +}; + /* * Tegra-specific GPIO API */
+/** + * Configure a list of GPIOs + * + * @param config List of GPIO configurations + * @param len Number of config items in list + */ +void gpio_config_table(const struct tegra_gpio_config *config, int len); + void gpio_info(void);
#define gpio_status() gpio_info() + #endif /* TEGRA_GPIO_H_ */ diff --git a/drivers/gpio/tegra_gpio.c b/drivers/gpio/tegra_gpio.c index 82b30d5ab682..fea9d17f8e62 100644 --- a/drivers/gpio/tegra_gpio.c +++ b/drivers/gpio/tegra_gpio.c @@ -221,6 +221,26 @@ int gpio_set_value(unsigned gpio, int value) return 0; }
+void gpio_config_table(const struct tegra_gpio_config *config, int len) +{ + int i; + + for (i = 0; i < len; i++) { + switch (config[i].init) { + case TEGRA_GPIO_INIT_IN: + gpio_direction_input(config[i].gpio); + break; + case TEGRA_GPIO_INIT_OUT0: + gpio_direction_output(config[i].gpio, 0); + break; + case TEGRA_GPIO_INIT_OUT1: + gpio_direction_output(config[i].gpio, 1); + break; + } + set_config(config[i].gpio, 1); + } +} + /* * Display Tegra GPIO information */