Re: [PATCH v7 2/2] drm/tiny: add driver for Apple Touch Bars in x86 Macs

[Aditya Garg <gargaditya08@live.com>]

> On 27 Feb 2025, at 3:04 PM, Thomas Zimmermann <tzimmermann@suse.de> wrote:
> 
> Hi
> 
>> Am 26.02.25 um 17:04 schrieb Aditya Garg:
>> From: Kerem Karabay <kekrby@gmail.com>
>> 
>> The Touch Bars found on x86 Macs support two USB configurations: one
>> where the device presents itself as a HID keyboard and can display
>> predefined sets of keys, and one where the operating system has full
>> control over what is displayed.
>> 
>> This commit adds support for the display functionality of the second
>> configuration. Functionality for the first configuration has been
>> merged in the HID tree.
>> 
>> Note that this driver has only been tested on T2 Macs, and only includes
>> the USB device ID for these devices. Testing on T1 Macs would be
>> appreciated.
>> 
>> Credit goes to Ben (Bingxing) Wang on GitHub for reverse engineering
>> most of the protocol.
>> 
>> Also, as requested by Andy, I would like to clarify the use of __packed
>> structs in this driver:
>> 
>> - All the packed structs are aligned except for appletbdrm_msg_information.
>> - We have to pack appletbdrm_msg_information since it is requirement of
>>   the protocol.
>> - We compared binaries compiled by keeping the rest structs __packed and
>>   not __packed using bloat-o-meter, and __packed was not affecting code
>>   generation.
>> - To maintain consistency, rest structs have been kept __packed.
>> 
>> I would also like to point out that since the driver was reverse-engineered
>> the actual data types of the protocol might be different, including, but
>> not limited to, endianness.
>> 
>> Link: https://github.com/imbushuo/DFRDisplayKm
>> Signed-off-by: Kerem Karabay <kekrby@gmail.com>
>> Co-developed-by: Atharva Tiwari <evepolonium@gmail.com>
>> Signed-off-by: Atharva Tiwari <evepolonium@gmail.com>
>> Co-developed-by: Aditya Garg <gargaditya08@live.com>
>> Signed-off-by: Aditya Garg <gargaditya08@live.com>
>> Signed-off-by: Aun-Ali Zaidi <admin@kodeit.net>
> 
> Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
> 
> Thanks for the effort. As far as I'm concerned, this driver looks good. If no further comments come in, I can add it to the DRM tree in a few days.

Thanks a lot Thomas, as well as Andy for reviewing the driver and making it better!