Re: [PATCH 2/2] staging: ti-soc-thermal: remove external heat while extrapolating hotspot

[Zhang Rui <rui.zhang@intel.com>]

On Fri, 2013-03-22 at 17:13 -0400, Eduardo Valentin wrote:
> For boards that provide a PCB sensor close to SoC junction
> temperature, it is possible to remove the cumulative heat
> reported by the SoC temperature sensor.
> 
> This patch changes the extrapolation computation to consider
> an external sensor in the extrapolation equations.
> 
> Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
> ---
>  drivers/staging/ti-soc-thermal/ti-thermal-common.c |    5 ++---
>  1 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/ti-soc-thermal/ti-thermal-common.c b/drivers/staging/ti-soc-thermal/ti-thermal-common.c
> index 231c549..52d3c1b 100644
> --- a/drivers/staging/ti-soc-thermal/ti-thermal-common.c
> +++ b/drivers/staging/ti-soc-thermal/ti-thermal-common.c
> @@ -92,10 +92,9 @@ static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal,
>  	if (ret)
>  		return ret;
>  
> -	pcb_temp = 0;
> -	/* TODO: Introduce pcb temperature lookup */
> +	ret = thermal_zone_lookup_temperature("pcb", &pcb_temp);
>  	/* In case pcb zone is available, use the extrapolation rule with it */
> -	if (pcb_temp) {
> +	if (!ret) {
>  		tmp -= pcb_temp;
>  		slope = s->slope_pcb;
>  		constant = s->constant_pcb;

I can not see this piece of code.
But I assume that the thermal_zone_device is registered in another
driver, right?
or else you can use the thermal_zone_device pointer directly instead.

thanks,
rui