Re: [PATCH v2] drm/i915/bxt: use NULL for GPIO connection ID

[Jani Nikula <jani.nikula@intel.com>]

On Fri, 18 Aug 2017, Mika Kahola <mika.kahola@intel.com> wrote:
> On Thu, 2017-08-17 at 14:06 +0300, Mika Kahola wrote:
>> Tested with GLK + MIPI/DSI panel (AU Optronics B101UAN01)
> Tested also with APL + MIPI/DSI setup.

Pushed to drm-intel-next-queued, thanks for the patch and testing.

BR,
Jani.


>
>> 
>> Tested-by: Mika Kahola <mika.kahola@intel.com>
>> 
>> On Thu, 2017-08-17 at 13:55 +0300, Andy Shevchenko wrote:
>> > 
>> > The commit 213e08ad60ba
>> > 	("drm/i915/bxt: add bxt dsi gpio element support")
>> > enables GPIO support for Broxton based platforms.
>> > 
>> > While using that API we might get into troubles in the future,
>> > because
>> > we can't rely on label name in the driver since vendor firmware
>> > might
>> > provide any GPIO pin there, e.g. "reset", and even mark it in _DSD
>> > (in
>> > which case the request will fail).
>> > 
>> > To avoid inconsistency and potential issues we have two options:
>> > a) generate GPIO ACPI mapping table and supply it via
>> >    acpi_dev_add_driver_gpios(), or
>> > b) just pass NULL as connection ID.
>> > 
>> > The b) approach is much simpler and would work since the driver
>> > relies
>> > on GPIO indices only. Moreover, the _CRS fallback mechanism, when
>> > requesting GPIO, has been made stricter, and supplying non-NULL
>> > connection ID when neither _DSD, nor GPIO ACPI mapping is present,
>> > is
>> > making request fail.
>> > 
>> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101921
>> > Fixes: f10e4bf6632b ("gpio: acpi: Even more tighten up ACPI GPIO
>> > lookups")
>> > Cc: Mika Kahola <mika.kahola@intel.com>
>> > Cc: Jani Nikula <jani.nikula@intel.com>
>> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>> > ---
>> > v2:
>> >  - adjust commit message for proper time tenses
>> >  - add Fixes: and Bugzilla: tags
>> >  drivers/gpu/drm/i915/intel_dsi_vbt.c | 2 +-
>> >  1 file changed, 1 insertion(+), 1 deletion(-)
>> > 
>> > diff --git a/drivers/gpu/drm/i915/intel_dsi_vbt.c
>> > b/drivers/gpu/drm/i915/intel_dsi_vbt.c
>> > index 7158c7ce9c09..91c07b0c8db9 100644
>> > --- a/drivers/gpu/drm/i915/intel_dsi_vbt.c
>> > +++ b/drivers/gpu/drm/i915/intel_dsi_vbt.c
>> > @@ -306,7 +306,7 @@ static void bxt_exec_gpio(struct
>> > drm_i915_private
>> > *dev_priv,
>> >  
>> >  	if (!gpio_desc) {
>> >  		gpio_desc = devm_gpiod_get_index(dev_priv-
>> > >drm.dev,
>> > -						 "panel",
>> > gpio_index,
>> > +						 NULL, gpio_index,
>> >  						 value ?
>> > GPIOD_OUT_LOW :
>> >  						 GPIOD_OUT_HIGH);
>> >  
>> _______________________________________________
>> dri-devel mailing list
>> dri-devel@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Jani Nikula, Intel Open Source Technology Center
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel