diff options
| author | Thierry Reding <treding@nvidia.com> | 2019-11-08 16:33:53 +0100 |
|---|---|---|
| committer | Bartosz Golaszewski <bgolaszewski@baylibre.com> | 2019-11-12 16:31:17 +0100 |
| commit | adce1183932265e94bbaf92138b9c98d1c5359b9 (patch) | |
| tree | e714b19bda376d1bb2508c0b6fe4f3bccfcdeb6c /drivers/gpio | |
| parent | gpio: tegra186: Program interrupt route mapping (diff) | |
| download | linux-adce1183932265e94bbaf92138b9c98d1c5359b9.tar.xz linux-adce1183932265e94bbaf92138b9c98d1c5359b9.zip | |
gpio: tegra186: Add debounce support
The GPIO controller found on Tegra186 and later supports debouncing for
inputs for up to 255 ms.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpio-tegra186.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-tegra186.c b/drivers/gpio/gpio-tegra186.c index cb5efb83bad4..55b43b7ce88d 100644 --- a/drivers/gpio/gpio-tegra186.c +++ b/drivers/gpio/gpio-tegra186.c @@ -32,6 +32,7 @@ #define TEGRA186_GPIO_ENABLE_CONFIG_TRIGGER_TYPE_DOUBLE_EDGE (0x3 << 2) #define TEGRA186_GPIO_ENABLE_CONFIG_TRIGGER_TYPE_MASK (0x3 << 2) #define TEGRA186_GPIO_ENABLE_CONFIG_TRIGGER_LEVEL BIT(4) +#define TEGRA186_GPIO_ENABLE_CONFIG_DEBOUNCE BIT(5) #define TEGRA186_GPIO_ENABLE_CONFIG_INTERRUPT BIT(6) #define TEGRA186_GPIO_DEBOUNCE_CONTROL 0x04 @@ -217,6 +218,42 @@ static void tegra186_gpio_set(struct gpio_chip *chip, unsigned int offset, writel(value, base + TEGRA186_GPIO_OUTPUT_VALUE); } +static int tegra186_gpio_set_config(struct gpio_chip *chip, + unsigned int offset, + unsigned long config) +{ + struct tegra_gpio *gpio = gpiochip_get_data(chip); + u32 debounce, value; + void __iomem *base; + + base = tegra186_gpio_get_base(gpio, offset); + if (base == NULL) + return -ENXIO; + + if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE) + return -ENOTSUPP; + + debounce = pinconf_to_config_argument(config); + + /* + * The Tegra186 GPIO controller supports a maximum of 255 ms debounce + * time. + */ + if (debounce > 255000) + return -EINVAL; + + debounce = DIV_ROUND_UP(debounce, USEC_PER_MSEC); + + value = TEGRA186_GPIO_DEBOUNCE_CONTROL_THRESHOLD(debounce); + writel(value, base + TEGRA186_GPIO_DEBOUNCE_CONTROL); + + value = readl(base + TEGRA186_GPIO_ENABLE_CONFIG); + value |= TEGRA186_GPIO_ENABLE_CONFIG_DEBOUNCE; + writel(value, base + TEGRA186_GPIO_ENABLE_CONFIG); + + return 0; +} + static int tegra186_gpio_of_xlate(struct gpio_chip *chip, const struct of_phandle_args *spec, u32 *flags) @@ -539,6 +576,7 @@ static int tegra186_gpio_probe(struct platform_device *pdev) gpio->gpio.direction_output = tegra186_gpio_direction_output; gpio->gpio.get = tegra186_gpio_get, gpio->gpio.set = tegra186_gpio_set; + gpio->gpio.set_config = tegra186_gpio_set_config; gpio->gpio.base = -1; |