Commit 5c9d8c4f authored Dec 12, 2017 by Brian Norris Committed by Linus Walleij Dec 20, 2017

pinctrl: rockchip: enable clock when reading pin direction register



We generally leave the GPIO clock disabled, unless an interrupt is
requested or we're accessing IO registers. We forgot to do this for the
->get_direction() callback, which means we can sometimes [1] get
incorrect results [2] from, e.g., /sys/kernel/debug/gpio.

Enable the clock, so we get the right results!

[1] Sometimes, because many systems have 1 or mor interrupt requested on
each GPIO bank, so they always leave their clock on.

[2] Incorrect, meaning the register returns 0, and so we interpret that
as "input".

Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

parent 51802d19

drivers/pinctrl/pinctrl-rockchip.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -2014,8 +2014,16 @@ static int rockchip_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
		{
		struct rockchip_pin_bank *bank = gpiochip_get_data(chip);
		u32 data;
		int ret;

		ret = clk_enable(bank->clk);
		if (ret < 0) {
		dev_err(bank->drvdata->dev,
		"failed to enable clock for bank %s\n", bank->name);
		return ret;
		}
		data = readl_relaxed(bank->reg_base + GPIO_SWPORT_DDR);
		clk_disable(bank->clk);

		return !(data & BIT(offset));
		}

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