From f62cebb951318578f0084e1d69a5ffd453c8683b Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Fri, 24 Sep 2021 01:46:40 +0300 Subject: [PATCH] gpio: pca953x: Improve bias setting The commit 68a0c306d101 ("gpio: pca953x: add ->set_config implementation") introduced support for bias setting. However this, due to being half-baked, brought potential issues: - the turning bias via disabling makes the pin floating for a while; - once enabled, bias can't be disabled. Fix all these by adding support for bias disabling and move the disabling part under the corresponding conditional. While at it, add support for default setting, since it's cheap to add. Fixes: 68a0c306d101 ("gpio: pca953x: add ->set_config implementation") Cc: Thomas Petazzoni Signed-off-by: Andy Shevchenko Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpio-pca953x.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index 8ebf369b3ba0f..d2fe76f3f34fd 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -559,21 +559,21 @@ static int pca953x_gpio_set_pull_up_down(struct pca953x_chip *chip, mutex_lock(&chip->i2c_lock); - /* Disable pull-up/pull-down */ - ret = regmap_write_bits(chip->regmap, pull_en_reg, bit, 0); - if (ret) - goto exit; - /* Configure pull-up/pull-down */ if (config == PIN_CONFIG_BIAS_PULL_UP) ret = regmap_write_bits(chip->regmap, pull_sel_reg, bit, bit); else if (config == PIN_CONFIG_BIAS_PULL_DOWN) ret = regmap_write_bits(chip->regmap, pull_sel_reg, bit, 0); + else + ret = 0; if (ret) goto exit; - /* Enable pull-up/pull-down */ - ret = regmap_write_bits(chip->regmap, pull_en_reg, bit, bit); + /* Disable/Enable pull-up/pull-down */ + if (config == PIN_CONFIG_BIAS_DISABLE) + ret = regmap_write_bits(chip->regmap, pull_en_reg, bit, 0); + else + ret = regmap_write_bits(chip->regmap, pull_en_reg, bit, bit); exit: mutex_unlock(&chip->i2c_lock); @@ -587,7 +587,9 @@ static int pca953x_gpio_set_config(struct gpio_chip *gc, unsigned int offset, switch (pinconf_to_config_param(config)) { case PIN_CONFIG_BIAS_PULL_UP: + case PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: case PIN_CONFIG_BIAS_PULL_DOWN: + case PIN_CONFIG_BIAS_DISABLE: return pca953x_gpio_set_pull_up_down(chip, offset, config); default: return -ENOTSUPP; -- 2.39.5