[Intel-gfx] [PATCH 01/14] drm/i915: Check for platform specific GPIO config

[Jani Nikula]

On Wed, 08 Feb 2017, "Srinivas, Vidya" <vidya.srinivas at intel.com> wrote:
>> -----Original Message-----
>> From: Jani Nikula [mailto:jani.nikula at linux.intel.com]
>> Sent: Wednesday, February 8, 2017 4:11 PM
>> To: Srinivas, Vidya <vidya.srinivas at intel.com>; intel-
>> gfx at lists.freedesktop.org
>> Subject: RE: [Intel-gfx] [PATCH 01/14] drm/i915: Check for platform specific
>> GPIO config
>> 
>> On Wed, 08 Feb 2017, "Srinivas, Vidya" <vidya.srinivas at intel.com> wrote:
>> >> -----Original Message-----
>> >> From: Jani Nikula [mailto:jani.nikula at linux.intel.com]
>> >> Sent: Monday, January 9, 2017 3:48 PM
>> >> To: Srinivas, Vidya <vidya.srinivas at intel.com>; intel-
>> >> gfx at lists.freedesktop.org
>> >> Subject: Re: [Intel-gfx] [PATCH 01/14] drm/i915: Check for platform
>> >> specific GPIO config
>> >>
>> >> On Mon, 09 Jan 2017, Vidya Srinivas <vidya.srinivas at intel.com> wrote:
>> >> > From: Uma Shankar <uma.shankar at intel.com>
>> >> >
>> >> > Panel GPIO control should be done based on platform. Add a check to
>> >> > restrict VLV and CHT specific GPIO confirguration, so that they
>> >> > dont apply to other platforms.
>> >>
>> >> There are no code paths that would have
>> >> dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC on platforms other
>> >> than VLV/CVH.
>> > This particular field is by default 0 which triggers a redundant gpio
>> > get operation for BXT. Hence limiting this to BYT/CHT platforms.
>> 
>> What do you mean by default 0? Are you saying that you have machines that
>> have a VBT which indicate they have PMIC backlight control when they in
>> fact don't?
>
> Sorry, what I meant is PPS_BLC_PMIC is 0. So even if the VBT field is
> not changed it will still become true causing the condition to pass.

In other words, the VBT contains PPS_BLC_PMIC for a machine that should
not use PMIC. In yet other words, the VBT contains incorrect
information. Right?

BR,
Jani.


>> 
>> BR,
>> Jani.
>> 
>> 
>> 
>> >
>> > Regards
>> > Vidya
>> >>
>> >> BR,
>> >> Jani.
>> >>
>> >> >
>> >> > Signed-off-by: Uma Shankar <uma.shankar at intel.com>
>> >> > ---
>> >> >  drivers/gpu/drm/i915/intel_dsi.c | 3 ++-
>> >> >  1 file changed, 2 insertions(+), 1 deletion(-)
>> >> >
>> >> > diff --git a/drivers/gpu/drm/i915/intel_dsi.c
>> >> > b/drivers/gpu/drm/i915/intel_dsi.c
>> >> > index 16732e7..27d8f95 100644
>> >> > --- a/drivers/gpu/drm/i915/intel_dsi.c
>> >> > +++ b/drivers/gpu/drm/i915/intel_dsi.c
>> >> > @@ -1560,7 +1560,8 @@ void intel_dsi_init(struct drm_i915_private
>> >> *dev_priv)
>> >> >  	 * In case of BYT with CRC PMIC, we need to use GPIO for
>> >> >  	 * Panel control.
>> >> >  	 */
>> >> > -	if (dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC) {
>> >> > +	if ((IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) &&
>> >> > +		(dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC)) {
>> >> >  		intel_dsi->gpio_panel =
>> >> >  			gpiod_get(dev->dev, "panel", GPIOD_OUT_HIGH);
>> >>
>> >> --
>> >> Jani Nikula, Intel Open Source Technology Center
>> 
>> --
>> Jani Nikula, Intel Open Source Technology Center

-- 
Jani Nikula, Intel Open Source Technology Center