Re: [PATCH v3 1/4] omapdrm: panel: fix compatible vendor string for td028ttec1

[H. Nikolaus Schaller]

> Am 01.12.2017 um 02:57 schrieb Rob Herring <robh@xxxxxxxxxx>:
> 
> On Tue, Nov 28, 2017 at 04:48:54PM +0100, H. Nikolaus Schaller wrote:
>> The vendor name was "toppoly" but other panels and the vendor list
>> have defined it as "tpo". So let's fix it in driver and bindings.
>> 
>> We keep the old definition in parallel to stay compatible with
>> potential older DTB setup.
>> 
>> Signed-off-by: H. Nikolaus Schaller <hns@xxxxxxxxxxxxx>
>> ---
>> .../display/panel/{toppoly,td028ttec1.txt => tpo,td028ttec1.txt}      | 4 ++--
>> drivers/gpu/drm/omapdrm/displays/panel-tpo-td028ttec1.c               | 3 +++
>> drivers/video/fbdev/omap2/omapfb/displays/panel-tpo-td028ttec1.c      | 3 +++
>> 3 files changed, 8 insertions(+), 2 deletions(-)
>> rename Documentation/devicetree/bindings/display/panel/{toppoly,td028ttec1.txt => tpo,td028ttec1.txt} (84%)
>> 
>> diff --git a/Documentation/devicetree/bindings/display/panel/toppoly,td028ttec1.txt b/Documentation/devicetree/bindings/display/panel/tpo,td028ttec1.txt
>> similarity index 84%
>> rename from Documentation/devicetree/bindings/display/panel/toppoly,td028ttec1.txt
>> rename to Documentation/devicetree/bindings/display/panel/tpo,td028ttec1.txt
>> index 7175dc3740ac..ed34253d9fb1 100644
>> --- a/Documentation/devicetree/bindings/display/panel/toppoly,td028ttec1.txt
>> +++ b/Documentation/devicetree/bindings/display/panel/tpo,td028ttec1.txt
>> @@ -2,7 +2,7 @@ Toppoly TD028TTEC1 Panel
>> ========================
>> 
>> Required properties:
>> -- compatible: "toppoly,td028ttec1"
>> +- compatible: "tpo,td028ttec1"
>> 
>> Optional properties:
>> - label: a symbolic name for the panel
>> @@ -14,7 +14,7 @@ Example
>> -------
>> 
>> lcd-panel: td028ttec1@0 {
>> -	compatible = "toppoly,td028ttec1";
>> +	compatible = "tpo,td028ttec1";
>> 	reg = <0>;
>> 	spi-max-frequency = <100000>;
>> 	spi-cpol;
>> diff --git a/drivers/gpu/drm/omapdrm/displays/panel-tpo-td028ttec1.c b/drivers/gpu/drm/omapdrm/displays/panel-tpo-td028ttec1.c
>> index 0a38a0e8c925..a0dfa14f4fab 100644
>> --- a/drivers/gpu/drm/omapdrm/displays/panel-tpo-td028ttec1.c
>> +++ b/drivers/gpu/drm/omapdrm/displays/panel-tpo-td028ttec1.c
>> @@ -452,6 +452,8 @@ static int td028ttec1_panel_remove(struct spi_device *spi)
>> }
>> 
>> static const struct of_device_id td028ttec1_of_match[] = {
>> +	{ .compatible = "omapdss,tpo,td028ttec1", },
> 
> Why the omapdss part?

I think because they are (currently and still) omapdrm
(omapdss) specific since SoC specific drivers for the
same panel may exist in parallel.

All panel drivers in drivers/gpu/drm/omapdrm/displays
have and need this prefix.

As far as I understand, the omapdss driver takes the
DTS compatible string, adds "omapdss," and then looks for
a panel driver to probe.

See also: Sebastian Reichel's comment to "[PATCH v3 4/4] DTS: Pandora: fix panel compatibility string"

BR,
Nikolaus Schaller