[PATCH] power: supply: qcom_battmgr: return EAGAIN when firmware service is not up

[PATCH] power: supply: qcom_battmgr: return EAGAIN when firmware service is not up

[Neil Armstrong]

The driver returns -ENODEV when the firmware battmrg service hasn't
started yet, while per-se -ENODEV is fine, we usually use -EAGAIN to
tell the user to retry again later. And the power supply core uses
-EGAIN when the device isn't initialized, let's use the same return.

This notably causes an infinite spam of:
thermal thermal_zoneXX: failed to read out thermal zone (-19)
because the thermal core doesn't understand -ENODEV, but only
considers -EAGAIN as a non-fatal error.

While it didn't appear until now, commit [1] fixes thermal core
and no more ignores thermal zones returning an error at first
temperature update.

[1] 5725f40698b9 ("thermal: core: Call monitor_thermal_zone() if zone temperature is invalid")

Link: https://lore.kernel.org/all/2ed4c630-204a-4f80-a37f-f2ca838eb455@linaro.org/
Cc: stable@vger.kernel.org
Fixes: 29e8142b5623 ("power: supply: Introduce Qualcomm PMIC GLINK power supply")
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
---
 drivers/power/supply/qcom_battmgr.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/power/supply/qcom_battmgr.c b/drivers/power/supply/qcom_battmgr.c
index 46f36dcb185c..bde874b5e0e7 100644
--- a/drivers/power/supply/qcom_battmgr.c
+++ b/drivers/power/supply/qcom_battmgr.c
@@ -486,7 +486,7 @@ static int qcom_battmgr_bat_get_property(struct power_supply *psy,
 	int ret;
 
 	if (!battmgr->service_up)
-		return -ENODEV;
+		return -EAGAIN;
 
 	if (battmgr->variant == QCOM_BATTMGR_SC8280XP)
 		ret = qcom_battmgr_bat_sc8280xp_update(battmgr, psp);
@@ -683,7 +683,7 @@ static int qcom_battmgr_ac_get_property(struct power_supply *psy,
 	int ret;
 
 	if (!battmgr->service_up)
-		return -ENODEV;
+		return -EAGAIN;
 
 	ret = qcom_battmgr_bat_sc8280xp_update(battmgr, psp);
 	if (ret)
@@ -748,7 +748,7 @@ static int qcom_battmgr_usb_get_property(struct power_supply *psy,
 	int ret;
 
 	if (!battmgr->service_up)
-		return -ENODEV;
+		return -EAGAIN;
 
 	if (battmgr->variant == QCOM_BATTMGR_SC8280XP)
 		ret = qcom_battmgr_bat_sc8280xp_update(battmgr, psp);
@@ -867,7 +867,7 @@ static int qcom_battmgr_wls_get_property(struct power_supply *psy,
 	int ret;
 
 	if (!battmgr->service_up)
-		return -ENODEV;
+		return -EAGAIN;
 
 	if (battmgr->variant == QCOM_BATTMGR_SC8280XP)
 		ret = qcom_battmgr_bat_sc8280xp_update(battmgr, psp);

---
base-commit: 91e3b24eb7d297d9d99030800ed96944b8652eaf
change-id: 20240715-topic-sm8x50-upstream-fix-battmgr-temp-tz-warn-c5a2f956d28d

Best regards,
-- 
Neil Armstrong <neil.armstrong@linaro.org>

Re: [PATCH] power: supply: qcom_battmgr: return EAGAIN when firmware service is not up

[Stephan Gerhold]

On Mon, Jul 15, 2024 at 02:57:06PM +0200, Neil Armstrong wrote:
> The driver returns -ENODEV when the firmware battmrg service hasn't
> started yet, while per-se -ENODEV is fine, we usually use -EAGAIN to
> tell the user to retry again later. And the power supply core uses
> -EGAIN when the device isn't initialized, let's use the same return.
> 
> This notably causes an infinite spam of:
> thermal thermal_zoneXX: failed to read out thermal zone (-19)
> because the thermal core doesn't understand -ENODEV, but only
> considers -EAGAIN as a non-fatal error.
> 
> While it didn't appear until now, commit [1] fixes thermal core
> and no more ignores thermal zones returning an error at first
> temperature update.
> 
> [1] 5725f40698b9 ("thermal: core: Call monitor_thermal_zone() if zone temperature is invalid")
> 
> Link: https://lore.kernel.org/all/2ed4c630-204a-4f80-a37f-f2ca838eb455@linaro.org/
> Cc: stable@vger.kernel.org
> Fixes: 29e8142b5623 ("power: supply: Introduce Qualcomm PMIC GLINK power supply")
> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>

The "failed to read out thermal zone (-19)" error happens on 6.10 on the
Qualcomm X1E80100 CRD too. This patch fixes it. Thanks for looking into
this! FWIW:

Tested-by: Stephan Gerhold <stephan.gerhold@linaro.org>
Reviewed-by: Stephan Gerhold <stephan.gerhold@linaro.org>

> ---
>  drivers/power/supply/qcom_battmgr.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/power/supply/qcom_battmgr.c b/drivers/power/supply/qcom_battmgr.c
> index 46f36dcb185c..bde874b5e0e7 100644
> --- a/drivers/power/supply/qcom_battmgr.c
> +++ b/drivers/power/supply/qcom_battmgr.c
> @@ -486,7 +486,7 @@ static int qcom_battmgr_bat_get_property(struct power_supply *psy,
>  	int ret;
>  
>  	if (!battmgr->service_up)
> -		return -ENODEV;
> +		return -EAGAIN;
>  
>  	if (battmgr->variant == QCOM_BATTMGR_SC8280XP)
>  		ret = qcom_battmgr_bat_sc8280xp_update(battmgr, psp);
> @@ -683,7 +683,7 @@ static int qcom_battmgr_ac_get_property(struct power_supply *psy,
>  	int ret;
>  
>  	if (!battmgr->service_up)
> -		return -ENODEV;
> +		return -EAGAIN;
>  
>  	ret = qcom_battmgr_bat_sc8280xp_update(battmgr, psp);
>  	if (ret)
> @@ -748,7 +748,7 @@ static int qcom_battmgr_usb_get_property(struct power_supply *psy,
>  	int ret;
>  
>  	if (!battmgr->service_up)
> -		return -ENODEV;
> +		return -EAGAIN;
>  
>  	if (battmgr->variant == QCOM_BATTMGR_SC8280XP)
>  		ret = qcom_battmgr_bat_sc8280xp_update(battmgr, psp);
> @@ -867,7 +867,7 @@ static int qcom_battmgr_wls_get_property(struct power_supply *psy,
>  	int ret;
>  
>  	if (!battmgr->service_up)
> -		return -ENODEV;
> +		return -EAGAIN;
>  
>  	if (battmgr->variant == QCOM_BATTMGR_SC8280XP)
>  		ret = qcom_battmgr_bat_sc8280xp_update(battmgr, psp);
> 
> ---
> base-commit: 91e3b24eb7d297d9d99030800ed96944b8652eaf
> change-id: 20240715-topic-sm8x50-upstream-fix-battmgr-temp-tz-warn-c5a2f956d28d
> 
> Best regards,
> -- 
> Neil Armstrong <neil.armstrong@linaro.org>
> 

Re: [PATCH] power: supply: qcom_battmgr: return EAGAIN when firmware service is not up

[Sebastian Reichel]

On Mon, 15 Jul 2024 14:57:06 +0200, Neil Armstrong wrote:
> The driver returns -ENODEV when the firmware battmrg service hasn't
> started yet, while per-se -ENODEV is fine, we usually use -EAGAIN to
> tell the user to retry again later. And the power supply core uses
> -EGAIN when the device isn't initialized, let's use the same return.
> 
> This notably causes an infinite spam of:
> thermal thermal_zoneXX: failed to read out thermal zone (-19)
> because the thermal core doesn't understand -ENODEV, but only
> considers -EAGAIN as a non-fatal error.
> 
> [...]

Applied, thanks!

[1/1] power: supply: qcom_battmgr: return EAGAIN when firmware service is not up
      commit: bf9d5cb588755ee41ac12a8976dccf44ae18281b

Best regards,
-- 
Sebastian Reichel <sebastian.reichel@collabora.com>