From 5c38a7ed9a9f8d4d474133b179c042e287c4fb74 Mon Sep 17 00:00:00 2001 From: Olivier Sobrie Date: Wed, 4 Mar 2026 22:20:39 +0100 Subject: hwmon: (max6639) fix inverted polarity [ Upstream commit 170a4b21f49b3dcff3115b4c90758f0a0d77375a ] According to MAX6639 documentation: D1: PWM Output Polarity. PWM output is low at 100% duty cycle when this bit is set to zero. PWM output is high at 100% duty cycle when this bit is set to 1. Up to commit 0f33272b60ed ("hwmon: (max6639) : Update hwmon init using info structure"), the polarity was set to high (0x2) when no platform data was set. After the patch, the polarity register wasn't set anymore if no platform data was specified. Nowadays, since commit 7506ebcd662b ("hwmon: (max6639) : Configure based on DT property"), it is always set to low which doesn't match with the comment above and change the behavior compared to versions prior 0f33272b60ed. Fixes: 0f33272b60ed ("hwmon: (max6639) : Update hwmon init using info structure") Signed-off-by: Olivier Sobrie Link: https://lore.kernel.org/r/20260304212039.570274-1-olivier@sobrie.be Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/max6639.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c index 32b4d54b2076..0b0a9f4c2307 100644 --- a/drivers/hwmon/max6639.c +++ b/drivers/hwmon/max6639.c @@ -615,7 +615,7 @@ static int max6639_init_client(struct i2c_client *client, return err; /* Fans PWM polarity high by default */ - err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x00); + err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x02); if (err) return err; -- cgit v1.2.3