1 files changed, 52 insertions, 0 deletions

diff --git a/drivers/pinctrl/pinctrl-rockchip.c b/drivers/pinctrl/pinctrl-rockchip.c
index 88d40772e387..1882713e68f9 100644
--- a/drivers/pinctrl/pinctrl-rockchip.c
+++ b/drivers/pinctrl/pinctrl-rockchip.c
@@ -2710,6 +2710,57 @@ static int rockchip_gpio_direction_output(struct gpio_chip *gc,
 	return pinctrl_gpio_direction_output(gc->base + offset);
 }
 
+static void rockchip_gpio_set_debounce(struct gpio_chip *gc,
+				       unsigned int offset, bool enable)
+{
+	struct rockchip_pin_bank *bank = gpiochip_get_data(gc);
+	void __iomem *reg = bank->reg_base + GPIO_DEBOUNCE;
+	unsigned long flags;
+	u32 data;
+
+	clk_enable(bank->clk);
+	raw_spin_lock_irqsave(&bank->slock, flags);
+
+	data = readl(reg);
+	if (enable)
+		data |= BIT(offset);
+	else
+		data &= ~BIT(offset);
+	writel(data, reg);
+
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
+	clk_disable(bank->clk);
+}
+
+/*
+ * gpiolib set_config callback function. The setting of the pin
+ * mux function as 'gpio output' will be handled by the pinctrl subsystem
+ * interface.
+ */
+static int rockchip_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
+				  unsigned long config)
+{
+	enum pin_config_param param = pinconf_to_config_param(config);
+
+	switch (param) {
+	case PIN_CONFIG_INPUT_DEBOUNCE:
+		rockchip_gpio_set_debounce(gc, offset, true);
+		/*
+		 * Rockchip's gpio could only support up to one period
+		 * of the debounce clock(pclk), which is far away from
+		 * satisftying the requirement, as pclk is usually near
+		 * 100MHz shared by all peripherals. So the fact is it
+		 * has crippled debounce capability could only be useful
+		 * to prevent any spurious glitches from waking up the system
+		 * if the gpio is conguired as wakeup interrupt source. Let's
+		 * still return -ENOTSUPP as before, to make sure the caller
+		 * of gpiod_set_debounce won't change its behaviour.
+		 */
+	default:
+		return -ENOTSUPP;
+	}
+}
+
 /*
  * gpiolib gpio_to_irq callback function. Creates a mapping between a GPIO pin
  * and a virtual IRQ, if not already present.
@@ -2735,6 +2786,7 @@ static const struct gpio_chip rockchip_gpiolib_chip = {
 	.get_direction	= rockchip_gpio_get_direction,
 	.direction_input = rockchip_gpio_direction_input,
 	.direction_output = rockchip_gpio_direction_output,
+	.set_config = rockchip_gpio_set_config,
 	.to_irq = rockchip_gpio_to_irq,
 	.owner = THIS_MODULE,
 };