[PATCH v3 0/7] drm/i2c: adv7511: ADV7533 support

[Archit Taneja]

Hi,

On 04/17/2016 05:01 PM, Xinliang Liu wrote:
> Hi Archit,
> Thank you for the patches.
>
> On 9 March 2016 at 18:57, Archit Taneja <architt at codeaurora.org> wrote:
>> ADV7533 is a DSI to HDMI encoder chip. It's like ADV7511, but with an
>> additional DSI RX block that takes in DSI video mode output.
>>
>> Trying to get this driver merged has had some challenges:
>>
>> - ADV7533 has an I2C control bus, but acts as a DSI peripheral too.
>>    After discussions, it was concluded that we'd want to provide an
>>    API to create MIPI DSI devices, rather than expose two different
>>    interfaces on DT. The first version [1] tried the former approach
>>    the second version [2] showed how the driver would look like if
>>    exposed 2 DT nodes. This lateset patchset relies on the MIPI DSI
>>    device creation API provided by [3], this has been accepted and
>>    should be merged for 4.6.
>>
>> - The driver was designed as an I2C slave encoder. When ADV7533
>>    patches were posted [1], it was modelled as a bridge, but ADV7511
>>    and others were still left as I2C slave encoders. This wasn't
>>    accepted. After discussions, it was decided that ADV7511 too would
>>    be converted into a bridge driver, and all the users of ADV7511
>>    should assume it is a bridge. This bridge conversion was done in
>>    [4]. There is still some debate over whether the bridge driver be
>>    involved in the connector creation, or the KMS driver that has
>>    the whole view of the display pipeline. This discussion shouldn't
>>    affect this patch set, though.
>
> I also agree with Laurent Pinchart that bridge driver shoudn't get
> involved in in the connector creation.
> It is better for KMS driver that has the whole view of the display pipeline.

Yes, that's the eventual plan. We were thinking of creating an
additional drm bridge api (drm_bridge_create_connector) that
helps the KMS driver create a connector for the bridge.

Since there are  certain connector related properties that the KMS
driver may not be aware of, we were thinking of creating another
drm_bridge op which fills up connector properties. Some properties
(like whether we want POLLED HPD or not) are more platform specific,
and would be parsed via the connector's DT node (that is, if DT is
supported on that platform)

For now, this series creates the connector in the bridge's
attach op, but relies on the KMS driver to call
drm_connector_register. The other stuff I mentioned above can come
later.

>
> In this case, I mean creating bridge driver to support ADV7533. I
> think this is something look like panel driver. Maybe we need to add
> some callback to the bridge to avoid creating connector in bridge
> driver.
> We can refer to panel entity to see what callbacks to be added. One
> callback I can see is the get_modes callback might be need.
>
>>
>> This patch set enables ADV7533 support with the above two issues
>> now resolved. It also incorporates ADV7533 specific features and fixes
>> that we've discovered since the first version of this patch was posted.
>>
>> Tested on ADV7533 chips on DB410c. It should work on the Hikey board too.
>
> I have tested the this tracking branch :
> https://git.linaro.org/landing-teams/working/qualcomm/kernel.git/shortlog/refs/heads/tracking-qcomlt-adv7511
> it works for HiKey.
> But it seems this patch set is a little different from the above
> branch. I think I need to tested this patch set.

Yes, it would be great if you could test the posted patch set and
provided a Tested-by. The patches "drm/i2c: adv7511: Init regulators"
and above need to still be applied from this branch. I'll post these
out in another patch set later.

Thanks,
Archit

>
> Thanks,
> -xinliang
>
>> I'd appreaciate if someone could test it on a ADV7511 platform since I
>> don't have one.
>>
>> [4]
>> https://lists.freedesktop.org/archives/dri-devel/2016-January/098287.html
>>
>> [3]
>> https://lkml.org/lkml/2016/2/12/67
>>
>> [2]
>> https://lists.freedesktop.org/archives/dri-devel/2015-September/089884.html
>>
>> [1]:
>> https://lists.freedesktop.org/archives/dri-devel/2015-July/087088.html
>>
>> Archit Taneja (7):
>>    drm/i2c: adv7511: Convert to drm_bridge
>>    drm/i2c: adv7511: Fix mutex deadlock when interrupts are disabled
>>    drm/i2c: adv7511: Initial support for ADV7533
>>    drm/i2c: adv7511: Create a MIPI DSI device
>>    drm/i2c: adv7511: Use internal timing generator
>>    drm/i2c: adv7511: Change number of DSI lanes dynamically
>>    dt-bindings: drm/bridge: Update bindings for ADV7533
>>
>>   .../bindings/display/bridge/adi,adv7511.txt        |  25 +-
>>   drivers/gpu/drm/i2c/adv7511.c                      | 539 +++++++++++++++++----
>>   2 files changed, 476 insertions(+), 88 deletions(-)
>>
>> --
>> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
>> hosted by The Linux Foundation
>>

-- 
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Forum, hosted by The Linux Foundation