FAILED: patch "[PATCH] hwmon: (npcm750-pwm-fan): stop fan timer on device detach" failed to apply to 5.10-stable tree

The patch below does not apply to the 5.10-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 <[email protected]>.

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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x f27f6976ea269219c1259a7c2f8c6dfe782540a3
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026080503-visor-oboe-4814@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

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

From f27f6976ea269219c1259a7c2f8c6dfe782540a3 Mon Sep 17 00:00:00 2001
From: Hongyan Xu <[email protected]>
Date: Wed, 29 Jul 2026 18:01:16 +0800
Subject: [PATCH] hwmon: (npcm750-pwm-fan): stop fan timer on device detach

When a fan tach channel is present, npcm7xx_pwm_fan_probe() starts fan_timer. The timer callback polls tach state and rearms the timer, but the driver has no remove callback or devm cleanup action to stop it. On device detach, the devm-managed driver data and I/O mappings can be released while the timer is still pending or running.

Register a devm cleanup action before starting the timer and shut the timer down synchronously from that action.

This issue was found by a static analysis tool.

index aea0b8659f5f..6ff2a6bc06c1 100644
@@ -358,6 +358,11 @@ static void npcm7xx_fan_polling(struct timer_list *t)
 	add_timer(&data->fan_timer);
 }
 
+static void npcm7xx_fan_cleanup(void *timer)
+{
+	timer_shutdown_sync(timer);
+}
+
 static inline void npcm7xx_fan_compute(struct npcm7xx_pwm_fan_data *data,
 				       u8 fan, u8 cmp, u8 fan_id, u8 flag_int,
 				       u8 flag_mode, u8 flag_clear)

@@ -1020,6 +1025,12 @@ static int npcm7xx_pwm_fan_probe(struct platform_device *pdev)
 				msecs_to_jiffies(NPCM7XX_FAN_POLL_TIMER_200MS);
 			timer_setup(&data->fan_timer,
 				    npcm7xx_fan_polling, 0);
+			ret = devm_add_action_or_reset(dev,
+						       npcm7xx_fan_cleanup,
+						       &data->fan_timer);
+			if (ret)
+				return ret;
+
 			add_timer(&data->fan_timer);
 			break;
 		}

From: Hongyan Xu <[email protected]>

[ Upstream commit f27f6976ea269219c1259a7c2f8c6dfe782540a3 ]

When a fan tach channel is present, npcm7xx_pwm_fan_probe() starts fan_timer. The timer callback polls tach state and rearms the timer, but the driver has no remove callback or devm cleanup action to stop it. On device detach, the devm-managed driver data and I/O mappings can be released while the timer is still pending or running.

Register a devm cleanup action before starting the timer and shut the timer down synchronously from that action.

This issue was found by a static analysis tool.

---
 drivers/hwmon/npcm750-pwm-fan.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

index 11a28609da3c7..dd34009c9400c 100644
@@ -360,6 +360,11 @@ static void npcm7xx_fan_polling(struct timer_list *t)
 	add_timer(&data->fan_timer);
 }
 
+static void npcm7xx_fan_cleanup(void *timer)
+{
+	timer_delete_sync(timer);
+}
+
 static inline void npcm7xx_fan_compute(struct npcm7xx_pwm_fan_data *data,
 				       u8 fan, u8 cmp, u8 fan_id, u8 flag_int,
 				       u8 flag_mode, u8 flag_clear)

@@ -1003,6 +1008,12 @@ static int npcm7xx_pwm_fan_probe(struct platform_device *pdev)
 				msecs_to_jiffies(NPCM7XX_FAN_POLL_TIMER_200MS);
 			timer_setup(&data->fan_timer,
 				    npcm7xx_fan_polling, 0);
+			ret = devm_add_action_or_reset(dev,
+						       npcm7xx_fan_cleanup,
+						       &data->fan_timer);
+			if (ret)
+				return ret;
+
 			add_timer(&data->fan_timer);
 			break;
 		}

2.53.0