FAILED: patch "[PATCH] hwmon: (gpd-fan) Reset both fans to automatic on duo boards" failed to apply to 6.18-stable tree

[Sasha Levin <sashal@kernel.org>]

The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x d1f60971fbf85c243ab6c78f6535fbc88fa640ce
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '20261109200325-failed-6.18-d1f60971fbf8@kernel.org' --subject-prefix 'PATCH 6.18.y' 'HEAD^..'

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From d1f60971fbf85c243ab6c78f6535fbc88fa640ce Mon Sep 17 00:00:00 2001
From: Alexei Solcanu <alexei.solcanu@pm.me>
Date: Sat, 26 Sep 2026 16:11:20 -0400
Subject: [PATCH] hwmon: (gpd-fan) Reset both fans to automatic on duo boards

On boards using gpd_duo_drvdata (GPD Duo, GPD Win 5), writing
pwm1_enable=2 only returns the first fan to EC control. The second fan
keeps its last manual duty cycle, e.g. full speed after pwm1=255, so a
fan control tool that exits leaves it running at that speed.

gpd_duo_write_pwm() writes both fan registers (pwm_write and
pwm_write + 1), but switching to automatic only clears pwm_write.
Also clear pwm_write + 1, so both fans return to EC control.

Tested on a GPD Win 5 (G1618-05). Not tested on the GPD Duo.

Fixes: 0ab88e239439 ("hwmon: add GPD devices sensor driver")
Cc: stable@vger.kernel.org
Signed-off-by: Alexei Solcanu <alexei.solcanu@pm.me>
Reviewed-by: Antheas Kapenekakis <lkml@antheas.dev>
Link: https://patch.msgid.link/20260926-gpd-fan-duo-auto-v2-1-0a2ea41ee3b5@pm.me
[groeck: Dropped obsolete 'Assisted-by: tag]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
 drivers/hwmon/gpd-fan.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/hwmon/gpd-fan.c b/drivers/hwmon/gpd-fan.c
index ed212615b2fe9..b3b75f99f5883 100644
--- a/drivers/hwmon/gpd-fan.c
+++ b/drivers/hwmon/gpd-fan.c
@@ -444,6 +444,7 @@ static void gpd_duo_set_pwm_enable(struct gpd_fan_data *data, enum FAN_PWM_ENABL
 		break;
 	case AUTOMATIC:
 		gpd_ecram_write(data->drvdata, data->drvdata->pwm_write, 0);
+		gpd_ecram_write(data->drvdata, data->drvdata->pwm_write + 1, 0);
 		break;
 	}
 }
-- 
2.53.0