Hi Tom,
On Sun, Mar 22, 2020 at 02:00:26PM +0100, Lukasz Majewski wrote:
This patch set is rather a request for testing (and a starting point for the discussion), as it may improve the robustness of USB with some pendrives - and yes sacrifice some performance for reliability. The previous version of this patch: https://patchwork.ozlabs.org/patch/1244928/ fixed issue for some network USB adapters and improved stability on TI boards. This patch also provides very detailed explanation of the problem in the commit message.
With the async support patch applied ( SHA1: 02b0e1a36c5bc20174299312556ec4e266872bd6 ), the qhtoken variable has value 0x00 when token shows errors. As a result the error handling path is not executed. This looks like some missing/broken cache flushing - for easier bisecting this patch has been reverted for now
Note that while the original patch returned USB ethernet on the Beagleboard to a functional state with this series applied it's back to non-functional.
Thanks for testing.
The _only_ difference between the first version of this patch and this one is the lack of dynamic reduction of transfer size for the latter. The former reduces the transfer size to 64 blocks (instead of default 240). And with 64 blocks it retries two times the transmission.
Best regards,
Lukasz Majewski
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