Re: [PATCH] thunderbolt: Fix Thunderbolt 3 display flickering issue on 2nd hot plug onwards

[Sanjay R Mehta <sanmehta@amd.com>]

On 7/11/2023 7:36 PM, Greg KH wrote:
> On Tue, Jul 11, 2023 at 02:27:50AM -0500, Sanjay R Mehta wrote:
>> From: Sanjay R Mehta <sanju.mehta@amd.com>
>>
>> Previously, on unplug events, the TMU mode was disabled first
>> followed by the Time Synchronization Handshake, irrespective of
>> whether the tb_switch_tmu_rate_write() API was successful or not.
>>
>> However, this caused a problem with Thunderbolt 3 (TBT3)
>> devices, as the TSPacketInterval bits were always enabled by default,
>> leading the host router to assume that the device router's TMU was
>> already enabled and preventing it from initiating the Time
>> Synchronization Handshake. As a result, TBT3 monitors experienced
>> display flickering from the second hot plug onwards.
>>
>> To address this issue, we have modified the code to only disable the
>> Time Synchronization Handshake during TMU disable if the
>> tb_switch_tmu_rate_write() function is successful. This ensures that
>> the TBT3 devices function correctly and eliminates the display
>> flickering issue.
>>
>> Signed-off-by: Sanath S <Sanath.S@amd.com>
>> Signed-off-by: Sanjay R Mehta <sanju.mehta@amd.com>
> 
> If "Sanath S" authored this patch, then the From: line is incorrect.
> 
> If they did not, then the ordering here is incorrect.
> 
> Either way, this isn't correct at all, please fix.
> 
> thanks,
> 
Sure Greg. my bad. I'll fix and resend this patch.
> greg k-h