Re: [PATCH] thermal: intel_pch_thermal: Fix enable check on Broadwell-DE

["Pandruvada, Srinivas" <srinivas.pandruvada@intel.com>]

On Wed, 2017-07-19 at 17:44 -0700, Ed Swierk wrote:
> Using the TSDSS flag to determine whether the thermal sensor is
> enabled is problematic. Broadwell-DE (Xeon D-1500) does not support
> dynamic shutdown and the TSDSS flag always reads 0 (contrary to the
> current datasheet). Even on hardware supporting dynamic shutdown, the
> driver does nothing to configure it, and the dynamic shutdown state
> should not prevent the driver from loading. The ETS flag itself
> indicates whether the thermal sensor is enabled, so use it instead of
> the TSDSS flag on all hardware platforms.
> 
> Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>
Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

> ---
>  drivers/thermal/intel_pch_thermal.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/thermal/intel_pch_thermal.c
> b/drivers/thermal/intel_pch_thermal.c
> index 2b49e8d..9889c90 100644
> --- a/drivers/thermal/intel_pch_thermal.c
> +++ b/drivers/thermal/intel_pch_thermal.c
> @@ -125,7 +125,7 @@ static int pch_wpt_init(struct pch_thermal_device
> *ptd, int *nr_trips)
>  	*nr_trips = 0;
>  
>  	/* Check if BIOS has already enabled thermal sensor */
> -	if (WPT_TSS_TSDSS & readb(ptd->hw_base + WPT_TSS)) {
> +	if (WPT_TSEL_ETS & readb(ptd->hw_base + WPT_TSEL)) {
>  		ptd->bios_enabled = true;
>  		goto read_trips;
>  	}
> @@ -141,7 +141,7 @@ static int pch_wpt_init(struct pch_thermal_device
> *ptd, int *nr_trips)
>  	}
>  
>  	writeb(tsel|WPT_TSEL_ETS, ptd->hw_base + WPT_TSEL);
> -	if (!(WPT_TSS_TSDSS & readb(ptd->hw_base + WPT_TSS))) {
> +	if (!(WPT_TSEL_ETS & readb(ptd->hw_base + WPT_TSEL))) {
>  		dev_err(&ptd->pdev->dev, "Sensor can't be
> enabled\n");
>  		return -ENODEV;
>  	}