On Thu, Oct 27, 2022 at 11:03:42AM +0200, Nicolas Dumazet wrote:
Before adding this quirk, this (mechanical keyboard) device would not be recognized, logging:
new full-speed USB device number 56 using xhci_hcd unable to read config index 0 descriptor/start: -32 chopping to 0 config(s)
It would take dozens of plugging/unpuggling cycles for the keyboard to be recognized. Keyboard seems to simply work after applying this quirk.
This issue had been reported by users in two places already ([1], [2]) but nobody tried upstreaming a patch yet. After testing I believe their suggested fix (DELAY_INIT + NO_LPM + DEVICE_QUALIFIER) was probably a little overkill. I assume this particular combination was tested because it had been previously suggested in [3], but only NO_LPM seems sufficient for this device.
Changes in v2:
- add the entry to the right location (sorting entries by vendor/device id).
Cc: stable@vger.kernel.org Signed-off-by: Nicolas Dumazet ndumazet@google.com
By putting your s-o-b below the --- line, tools will drop it, how did you test this?
Put the v2 stuff below the --- line, don't add a new one. See the thousands of examples on the list for how to do this correctly (as well as the kernel documentation.)
Can you fix this up and resend a v3 please?
thanks,
greg k-h