mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
* [PATCH v2] wifi: ath10k: Stop unanswered temperature reads
@ 2026-10-27  1:56 Filippo Falezza
  2026-10-27  8:43 ` Loic Poulain
  0 siblings, 1 reply; 2+ messages in thread
From: Filippo Falezza @ 2026-10-27  1:56 UTC (permalink / raw)
  To: Jeff Johnson
  Cc: Kalle Valo, Loic Poulain, linux-wireless, ath10k, linux-kernel,
	Filippo Falezza

Reading the ath10k hwmon temperature sends WMI_PDEV_GET_TEMPERATURE and
waits up to 5 s (ATH10K_THERMAL_SYNC_TIMEOUT_HZ) for the reply event,
holding conf_mutex. Not all firmware answers: the WCN3990 firmware
WLAN.HL.3.3.1-00694-QCAHLSWMTPLZ-1 on a Motorola Moto G 5G Plus
codename nairo (SM7250) never sends the event, so every read of
temp1_input stalls for 5 s, logs

  ath10k_snoc 18800000.wifi: failed to synchronize thermal read

and returns -ETIMEDOUT. Tools that read all hwmon sensors, such as
lm-sensors, hang for 5 s on every run, and configuration changes of the
interface wait for conf_mutex in the meantime.

Whether the firmware answers cannot be told from the chip: firmware that
answers and firmware that does not both advertise
WMI_SERVICE_THERM_THROT, and WCN3990 firmware differs between devices.
Instead, remember that the running firmware did not answer, and return
-EOPNOTSUPP right away on later reads. Forget it when the firmware
starts, so that a restarted or updated firmware is asked again.

The first read after each firmware start still takes 5 s when the
firmware does not answer. Reads on firmware that answers are unchanged.

This change was written with the help of an AI coding assistant; see
the notes below.

Fixes: e98199a8c27f ("ath10k: enable QCA6174/QCA9377 to read the chip temperature")
Signed-off-by: Filippo Falezza <effeffe99@gmail.com>
---
Hello there,

this is v2 of the fix for ath10k temperature reads that stall for 5 s
on firmware that never answers the request, as on the WCN3990 firmware
of a Motorola Moto G 5G Plus (SM7250).

The only change from v1 is the name of the flag: it is now
ath10k_thermal.broken, as Loic suggested, instead of
temperature_unanswered. The behaviour is the same, so the testing from
v1 still applies: on the phone, the first read after the firmware
starts times out once after 5 s, every later read returns -EOPNOTSUPP
within milliseconds, and a full `sensors` run takes 25 ms instead of
5 s or more. Restarting Wi-Fi makes the driver ask the firmware again.
I have not tested firmware that answers the request.

v2 builds with W=1 for arm64 and is checkpatch --strict clean, on top
of ath-next (cd026e68fdbf).

As with v1, I wrote this with the help of an AI coding assistant
(Claude Code); the testing is on the phone.

Thanks,
Filippo
---
Changes in v2:
- Rename temperature_unanswered to broken, as suggested by Loic Poulain.
- Link to v1: https://patch.msgid.link/20261026-ath10k-temperature-v1-1-e5cd6fde7f1e@gmail.com
---
 drivers/net/wireless/ath/ath10k/core.c    | 1 +
 drivers/net/wireless/ath/ath10k/thermal.c | 9 ++++++++-
 drivers/net/wireless/ath/ath10k/thermal.h | 2 ++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath10k/core.c b/drivers/net/wireless/ath/ath10k/core.c
index 7c2939cbde5f..a749ae582b0a 100644
--- a/drivers/net/wireless/ath/ath10k/core.c
+++ b/drivers/net/wireless/ath/ath10k/core.c
@@ -2985,6 +2985,7 @@ int ath10k_core_start(struct ath10k *ar, enum ath10k_firmware_mode mode,
 	clear_bit(ATH10K_FLAG_CRASH_FLUSH, &ar->dev_flags);
 
 	ar->running_fw = fw;
+	ar->thermal.broken = false;
 
 	if (!test_bit(ATH10K_FW_FEATURE_NON_BMI,
 		      ar->running_fw->fw_file.fw_features)) {
diff --git a/drivers/net/wireless/ath/ath10k/thermal.c b/drivers/net/wireless/ath/ath10k/thermal.c
index 9bb486f8e920..9ff7de0abd12 100644
--- a/drivers/net/wireless/ath/ath10k/thermal.c
+++ b/drivers/net/wireless/ath/ath10k/thermal.c
@@ -75,6 +75,12 @@ static ssize_t ath10k_thermal_show_temp(struct device *dev,
 		goto out;
 	}
 
+	/* Don't stall every read on firmware that never answers */
+	if (ar->thermal.broken) {
+		ret = -EOPNOTSUPP;
+		goto out;
+	}
+
 	reinit_completion(&ar->thermal.wmi_sync);
 	ret = ath10k_wmi_pdev_get_temperature(ar);
 	if (ret) {
@@ -90,7 +96,8 @@ static ssize_t ath10k_thermal_show_temp(struct device *dev,
 	time_left = wait_for_completion_timeout(&ar->thermal.wmi_sync,
 						ATH10K_THERMAL_SYNC_TIMEOUT_HZ);
 	if (!time_left) {
-		ath10k_warn(ar, "failed to synchronize thermal read\n");
+		ath10k_warn(ar, "failed to synchronize thermal read, not asking again until the firmware restarts\n");
+		ar->thermal.broken = true;
 		ret = -ETIMEDOUT;
 		goto out;
 	}
diff --git a/drivers/net/wireless/ath/ath10k/thermal.h b/drivers/net/wireless/ath/ath10k/thermal.h
index 1f4de9fbf2b3..d1fb5b958c37 100644
--- a/drivers/net/wireless/ath/ath10k/thermal.h
+++ b/drivers/net/wireless/ath/ath10k/thermal.h
@@ -19,6 +19,8 @@ struct ath10k_thermal {
 	/* protected by conf_mutex */
 	u32 throttle_state;
 	u32 quiet_period;
+	/* the running firmware did not answer a temperature request */
+	bool broken;
 	/* temperature value in Celsius degree
 	 * protected by data_lock
 	 */

---
base-commit: cd026e68fdbf88b9cc522b76c7a9d92c9a41f709
change-id: 20261022-ath10k-temperature-22b119fd615c

Best regards,
--  
Filippo Falezza <effeffe99@gmail.com>


^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [PATCH v2] wifi: ath10k: Stop unanswered temperature reads
  2026-10-27  1:56 [PATCH v2] wifi: ath10k: Stop unanswered temperature reads Filippo Falezza
@ 2026-10-27  8:43 ` Loic Poulain
  0 siblings, 0 replies; 2+ messages in thread
From: Loic Poulain @ 2026-10-27  8:43 UTC (permalink / raw)
  To: Filippo Falezza
  Cc: Jeff Johnson, Kalle Valo, linux-wireless, ath10k, linux-kernel

On Tue, Oct 27, 2026 at 2:56 AM Filippo Falezza <effeffe99@gmail.com> wrote:
>
> Reading the ath10k hwmon temperature sends WMI_PDEV_GET_TEMPERATURE and
> waits up to 5 s (ATH10K_THERMAL_SYNC_TIMEOUT_HZ) for the reply event,
> holding conf_mutex. Not all firmware answers: the WCN3990 firmware
> WLAN.HL.3.3.1-00694-QCAHLSWMTPLZ-1 on a Motorola Moto G 5G Plus
> codename nairo (SM7250) never sends the event, so every read of
> temp1_input stalls for 5 s, logs
>
>   ath10k_snoc 18800000.wifi: failed to synchronize thermal read
>
> and returns -ETIMEDOUT. Tools that read all hwmon sensors, such as
> lm-sensors, hang for 5 s on every run, and configuration changes of the
> interface wait for conf_mutex in the meantime.
>
> Whether the firmware answers cannot be told from the chip: firmware that
> answers and firmware that does not both advertise
> WMI_SERVICE_THERM_THROT, and WCN3990 firmware differs between devices.
> Instead, remember that the running firmware did not answer, and return
> -EOPNOTSUPP right away on later reads. Forget it when the firmware
> starts, so that a restarted or updated firmware is asked again.
>
> The first read after each firmware start still takes 5 s when the
> firmware does not answer. Reads on firmware that answers are unchanged.
>
> This change was written with the help of an AI coding assistant; see
> the notes below.
>
> Fixes: e98199a8c27f ("ath10k: enable QCA6174/QCA9377 to read the chip temperature")
> Signed-off-by: Filippo Falezza <effeffe99@gmail.com>

Reviewed-by: Loic Poulain <loic.poulain@oss.qualcomm.com>

> ---
> Hello there,
>
> this is v2 of the fix for ath10k temperature reads that stall for 5 s
> on firmware that never answers the request, as on the WCN3990 firmware
> of a Motorola Moto G 5G Plus (SM7250).
>
> The only change from v1 is the name of the flag: it is now
> ath10k_thermal.broken, as Loic suggested, instead of
> temperature_unanswered. The behaviour is the same, so the testing from
> v1 still applies: on the phone, the first read after the firmware
> starts times out once after 5 s, every later read returns -EOPNOTSUPP
> within milliseconds, and a full `sensors` run takes 25 ms instead of
> 5 s or more. Restarting Wi-Fi makes the driver ask the firmware again.
> I have not tested firmware that answers the request.
>
> v2 builds with W=1 for arm64 and is checkpatch --strict clean, on top
> of ath-next (cd026e68fdbf).
>
> As with v1, I wrote this with the help of an AI coding assistant
> (Claude Code); the testing is on the phone.
>
> Thanks,
> Filippo
> ---
> Changes in v2:
> - Rename temperature_unanswered to broken, as suggested by Loic Poulain.
> - Link to v1: https://patch.msgid.link/20261026-ath10k-temperature-v1-1-e5cd6fde7f1e@gmail.com
> ---
>  drivers/net/wireless/ath/ath10k/core.c    | 1 +
>  drivers/net/wireless/ath/ath10k/thermal.c | 9 ++++++++-
>  drivers/net/wireless/ath/ath10k/thermal.h | 2 ++
>  3 files changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/ath/ath10k/core.c b/drivers/net/wireless/ath/ath10k/core.c
> index 7c2939cbde5f..a749ae582b0a 100644
> --- a/drivers/net/wireless/ath/ath10k/core.c
> +++ b/drivers/net/wireless/ath/ath10k/core.c
> @@ -2985,6 +2985,7 @@ int ath10k_core_start(struct ath10k *ar, enum ath10k_firmware_mode mode,
>         clear_bit(ATH10K_FLAG_CRASH_FLUSH, &ar->dev_flags);
>
>         ar->running_fw = fw;
> +       ar->thermal.broken = false;
>
>         if (!test_bit(ATH10K_FW_FEATURE_NON_BMI,
>                       ar->running_fw->fw_file.fw_features)) {
> diff --git a/drivers/net/wireless/ath/ath10k/thermal.c b/drivers/net/wireless/ath/ath10k/thermal.c
> index 9bb486f8e920..9ff7de0abd12 100644
> --- a/drivers/net/wireless/ath/ath10k/thermal.c
> +++ b/drivers/net/wireless/ath/ath10k/thermal.c
> @@ -75,6 +75,12 @@ static ssize_t ath10k_thermal_show_temp(struct device *dev,
>                 goto out;
>         }
>
> +       /* Don't stall every read on firmware that never answers */
> +       if (ar->thermal.broken) {
> +               ret = -EOPNOTSUPP;
> +               goto out;
> +       }
> +
>         reinit_completion(&ar->thermal.wmi_sync);
>         ret = ath10k_wmi_pdev_get_temperature(ar);
>         if (ret) {
> @@ -90,7 +96,8 @@ static ssize_t ath10k_thermal_show_temp(struct device *dev,
>         time_left = wait_for_completion_timeout(&ar->thermal.wmi_sync,
>                                                 ATH10K_THERMAL_SYNC_TIMEOUT_HZ);
>         if (!time_left) {
> -               ath10k_warn(ar, "failed to synchronize thermal read\n");
> +               ath10k_warn(ar, "failed to synchronize thermal read, not asking again until the firmware restarts\n");
> +               ar->thermal.broken = true;
>                 ret = -ETIMEDOUT;
>                 goto out;
>         }
> diff --git a/drivers/net/wireless/ath/ath10k/thermal.h b/drivers/net/wireless/ath/ath10k/thermal.h
> index 1f4de9fbf2b3..d1fb5b958c37 100644
> --- a/drivers/net/wireless/ath/ath10k/thermal.h
> +++ b/drivers/net/wireless/ath/ath10k/thermal.h
> @@ -19,6 +19,8 @@ struct ath10k_thermal {
>         /* protected by conf_mutex */
>         u32 throttle_state;
>         u32 quiet_period;
> +       /* the running firmware did not answer a temperature request */
> +       bool broken;
>         /* temperature value in Celsius degree
>          * protected by data_lock
>          */
>
> ---
> base-commit: cd026e68fdbf88b9cc522b76c7a9d92c9a41f709
> change-id: 20261022-ath10k-temperature-22b119fd615c
>
> Best regards,
> --
> Filippo Falezza <effeffe99@gmail.com>
>

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2026-10-27  8:43 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2026-10-27  1:56 [PATCH v2] wifi: ath10k: Stop unanswered temperature reads Filippo Falezza
2026-10-27  8:43 ` Loic Poulain

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®