From fae1466da92d6627b5c938064ad42dac2aa88cc4 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Thu, 9 Mar 2023 16:49:48 +0100 Subject: [PATCH] pinctrl: qcom: lpass-lpi: allow glitch-free output GPIO When choosing GPIO function for pins, use the same glitch-free method as main TLMM pinctrl-msm.c driver in msm_pinmux_set_mux(). This replicates the commit d21f4b7ffc22 ("pinctrl: qcom: Avoid glitching lines when we first mux to output") to LPASS pin controller with same justification. Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20230309154949.658380-3-krzysztof.kozlowski@linaro.org Signed-off-by: Linus Walleij --- drivers/pinctrl/qcom/pinctrl-lpass-lpi.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c b/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c index bd32556d75a5..fdb6585a9234 100644 --- a/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c +++ b/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c @@ -19,6 +19,8 @@ #include "pinctrl-lpass-lpi.h" +#define MAX_NR_GPIO 23 +#define GPIO_FUNC 0 #define MAX_LPI_NUM_CLKS 2 struct lpi_pinctrl { @@ -30,6 +32,7 @@ struct lpi_pinctrl { char __iomem *slew_base; struct clk_bulk_data clks[MAX_LPI_NUM_CLKS]; struct mutex slew_access_lock; + DECLARE_BITMAP(ever_gpio, MAX_NR_GPIO); const struct lpi_pinctrl_variant_data *data; }; @@ -100,6 +103,28 @@ static int lpi_gpio_set_mux(struct pinctrl_dev *pctldev, unsigned int function, return -EINVAL; val = lpi_gpio_read(pctrl, pin, LPI_GPIO_CFG_REG); + + /* + * If this is the first time muxing to GPIO and the direction is + * output, make sure that we're not going to be glitching the pin + * by reading the current state of the pin and setting it as the + * output. + */ + if (i == GPIO_FUNC && (val & LPI_GPIO_OE_MASK) && + !test_and_set_bit(group, pctrl->ever_gpio)) { + u32 io_val = lpi_gpio_read(pctrl, group, LPI_GPIO_VALUE_REG); + + if (io_val & LPI_GPIO_VALUE_IN_MASK) { + if (!(io_val & LPI_GPIO_VALUE_OUT_MASK)) + lpi_gpio_write(pctrl, group, LPI_GPIO_VALUE_REG, + io_val | LPI_GPIO_VALUE_OUT_MASK); + } else { + if (io_val & LPI_GPIO_VALUE_OUT_MASK) + lpi_gpio_write(pctrl, group, LPI_GPIO_VALUE_REG, + io_val & ~LPI_GPIO_VALUE_OUT_MASK); + } + } + u32p_replace_bits(&val, i, LPI_GPIO_FUNCTION_MASK); lpi_gpio_write(pctrl, pin, LPI_GPIO_CFG_REG, val); @@ -394,6 +419,9 @@ int lpi_pinctrl_probe(struct platform_device *pdev) if (!data) return -EINVAL; + if (WARN_ON(data->npins > MAX_NR_GPIO)) + return -EINVAL; + pctrl->data = data; pctrl->dev = &pdev->dev; -- 2.11.0