[PATCH 1/3] thermal: handle get_temp() errors properly

[Caesar Wang]

Brian,
在 2016年11月19日 07:52, Brian Norris 写道:
> If using CONFIG_THERMAL_EMULATION, there's a corner case where we might
> get an error from the zone's get_temp() callback, but we'll ignore that
> and keep using its value. Let's just error out properly instead.
>
> Signed-off-by: Brian Norris <briannorris at chromium.org>
Tested-by: Caesar Wang <wxt at rock-chips.com>

[    8.111296] thermal thermal_zone4: power_allocator: sustainable_power 
will be estimated
[    8.119420] thermal_zone_get_temp:537 the ret=-19, no such device, 
look like the A/D value had no ready yet.
..
Anyway, this patch is useful for improving thermal.

-Caesar
> ---
>   drivers/thermal/thermal_core.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index 911fd964c742..0fa497f10d25 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -494,6 +494,8 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp)
>   	mutex_lock(&tz->lock);
>   
>   	ret = tz->ops->get_temp(tz, temp);
> +	if (ret)
> +		goto exit_unlock;
>   
>   	if (IS_ENABLED(CONFIG_THERMAL_EMULATION) && tz->emul_temperature) {
>   		for (count = 0; count < tz->trips; count++) {
> @@ -514,6 +516,7 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp)
>   			*temp = tz->emul_temperature;
>   	}
>    
> +exit_unlock:
>   	mutex_unlock(&tz->lock);
>   exit:
>   	return ret;