Changing the direction before updating the output value in the OUTPUT_VAL register may result in a glitch on the output line if the previous value in the OUTPUT_VAL register is different from the one we want to set.
In order to avoid that, update the output value before changing the direction.
Cc: stable@vger.kernel.org Fixes: 6702abb3bf23 ("pinctrl: armada-37xx: Fix direction_output() callback behavior") Signed-off-by: Imre Kaloz kaloz@openwrt.org Reviewed-by: Andrew Lunn andrew@lunn.ch Signed-off-by: Gabor Juhos j4g8y7@gmail.com --- Changes in v2: - swap with patch 3 from v1 - add 'Reviewed-by' tag from Andrew - reorder 'Signed-off-by' tags (result of 'b4 trailers -u') --- drivers/pinctrl/mvebu/pinctrl-armada-37xx.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-)
diff --git a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c index 43034d29292687e875136aafa530b62479dc55ec..79f9c08e5039c31acb170d4f38b516b1454fd9ea 100644 --- a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c +++ b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c @@ -417,23 +417,22 @@ static int armada_37xx_gpio_direction_output(struct gpio_chip *chip, unsigned int offset, int value) { struct armada_37xx_pinctrl *info = gpiochip_get_data(chip); - unsigned int val_offset = offset; - unsigned int reg = OUTPUT_EN; + unsigned int en_offset = offset; + unsigned int reg = OUTPUT_VAL; unsigned int mask, val, ret;
armada_37xx_update_reg(®, &offset); mask = BIT(offset); + val = value ? mask : 0;
- ret = regmap_update_bits(info->regmap, reg, mask, mask); - + ret = regmap_update_bits(info->regmap, reg, mask, val); if (ret) return ret;
- reg = OUTPUT_VAL; - armada_37xx_update_reg(®, &val_offset); + reg = OUTPUT_EN; + armada_37xx_update_reg(®, &en_offset);
- val = value ? mask : 0; - regmap_update_bits(info->regmap, reg, mask, val); + regmap_update_bits(info->regmap, reg, mask, mask);
return 0; }