[UBOOT PATCH 0/3] Port the usb reset patches from linux

[Marek Vasut]

On 5/17/23 08:37, Michal Simek wrote:
> Hi,

Hi,

> On 5/8/23 13:56, Marek Vasut wrote:
>> On 5/8/23 05:00, Venkatesh Yadav Abbarapu wrote:
>>> Port the usb reset patches from linux kernel.
>>
>> What kind of patches are these ?
>> What sort of problem are those patches attempting to address ?
>>
>>> Venkatesh Yadav Abbarapu (3):
>>>    usb: dwc3: core: improve reset sequence
>>>    usb: dwc3: gadget: Don't send unintended link state change
>>>    usb: dwc3: core: Only handle soft-reset in DCTL
>>
>> These seem to be randomly picked patches from Linux 4.7, 5.5 ... but 
>> there seem to be a huge amount of backports missing inbetween, which 
>> would create a tremendous maintenance burden of the DWC3 driver.
>>
>> Can you please instead pick ALL the missing patches from Linux, so 
>> that the DWC3 driver is instead synchronized with Linux, rather than 
>> diverging and growing partial backports ?
>>
>> It shouldn't be difficult, one approach I can think of is roughly this:
>> - figure out the original merge base from which the DWC3 driver was 
>> imported to U-Boot
>> - in U-Boot, revert all dwc3 patches on top of that import patch
>> - pick all Linux kernel dwc3 patches from that merge base and apply on 
>> top of this U-Boot with reverts
>> - Run rebase and drop the reverts, let git drop duplicate patches
> 
> Based on internal discussion decision was made to keep these patches 
> only in soc vendor tree. We are not happy with it but we are not going 
> to invest our time and take responsibility for the driver 
> synchronization work at this point.

That's unfortunate, as I spent considerable amount of time explaining 
and re-explaining how to perform this synchronization in very much 
automated manner. It would be nice to know whether AMD attempted this 
approach and get a report back regarding any difficulties with that 
approach.

> That's why if you insist on full synchronization with Linux version 
> please ignore this patchset and also serarate dwc3 clock patch.

I already tried to explain this multiple times before, picking random 
patches into the DWC3 driver would make the full synchronization more 
difficult later, and it would make maintaining the driver harder too.