>-----Original Message----- >From: Jani Nikula [mailto:jani.nikula@xxxxxxxxxxxxxxx] >Sent: Wednesday, February 8, 2017 5:58 PM >To: Shankar, Uma <uma.shankar@xxxxxxxxx>; Srinivas, Vidya ><vidya.srinivas@xxxxxxxxx>; intel-gfx@xxxxxxxxxxxxxxxxxxxxx >Subject: RE: [PATCH 01/14] drm/i915: Check for platform specific >GPIO config > >On Wed, 08 Feb 2017, "Shankar, Uma" <uma.shankar@xxxxxxxxx> wrote: >>>-----Original Message----- >>>From: Intel-gfx [mailto:intel-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx] On >>>Behalf Of Jani Nikula >>>Sent: Wednesday, February 8, 2017 4:41 PM >>>To: Srinivas, Vidya <vidya.srinivas@xxxxxxxxx>; intel- >>>gfx@xxxxxxxxxxxxxxxxxxxxx >>>Subject: Re: [PATCH 01/14] drm/i915: Check for platform >>>specific GPIO config >>> >>>On Wed, 08 Feb 2017, "Srinivas, Vidya" <vidya.srinivas@xxxxxxxxx> wrote: >>>>> -----Original Message----- >>>>> From: Jani Nikula [mailto:jani.nikula@xxxxxxxxxxxxxxx] >>>>> Sent: Wednesday, February 8, 2017 4:11 PM >>>>> To: Srinivas, Vidya <vidya.srinivas@xxxxxxxxx>; intel- >>>>> gfx@xxxxxxxxxxxxxxxxxxxxx >>>>> Subject: RE: [PATCH 01/14] drm/i915: Check for platform >>>>> specific GPIO config >>>>> >>>>> On Wed, 08 Feb 2017, "Srinivas, Vidya" <vidya.srinivas@xxxxxxxxx> >wrote: >>>>> >> -----Original Message----- >>>>> >> From: Jani Nikula [mailto:jani.nikula@xxxxxxxxxxxxxxx] >>>>> >> Sent: Monday, January 9, 2017 3:48 PM >>>>> >> To: Srinivas, Vidya <vidya.srinivas@xxxxxxxxx>; intel- >>>>> >> gfx@xxxxxxxxxxxxxxxxxxxxx >>>>> >> Subject: Re: [PATCH 01/14] drm/i915: Check for >>>>> >> platform specific GPIO config >>>>> >> >>>>> >> On Mon, 09 Jan 2017, Vidya Srinivas <vidya.srinivas@xxxxxxxxx> >wrote: >>>>> >> > From: Uma Shankar <uma.shankar@xxxxxxxxx> >>>>> >> > >>>>> >> > 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? >>> >> >> Hi Jani, >> In this case, I guess the design for this value itself is wrong. A >> value of 0 is a valid value from driver/vbt perspective (basically >> signifies some logical entity). Thus if we don't touch this field in >> VBT, it will still have 0 as a value (un-initialized). Driver will consider it to be >right and will go ahead with GPIO get calls. Ideally this should start from index >as 1 or a default value of -1 was needed. >> >> In BYT/CHT, most platforms will be using that hence things were fine. >> If a board design needed other value, VBT field would have been >> updated. But this is not at all needed for platforms beyond BYT/CHT, hence >this change was limited to those platforms. > >I filed a bug against the spec. That's where this info should be. > >BR, >Jani. Thanks Jani for filing this. Can you please point to the bug link ? Regards, Uma Shankar >>>>> >> > >>>>> >> > Signed-off-by: Uma Shankar <uma.shankar@xxxxxxxxx> >>>>> >> > --- >>>>> >> > 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 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
