This is a note to let you know that I've just added the patch titled
usb: add NO_LPM quirk for Realforce 87U Keyboard
to the 6.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-add-no_lpm-quirk-for-realforce-87u-keyboard.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 181135bb20dcb184edd89817831b888eb8132741 Mon Sep 17 00:00:00 2001
From: Nicolas Dumazet <ndumazet@xxxxxxxxxx>
Date: Wed, 9 Nov 2022 13:29:46 +0100
Subject: usb: add NO_LPM quirk for Realforce 87U Keyboard
From: Nicolas Dumazet <ndumazet@xxxxxxxxxx>
commit 181135bb20dcb184edd89817831b888eb8132741 upstream.
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.
[1]: https://qiita.com/float168/items/fed43d540c8e2201b543
[2]: https://blog.kostic.dev/posts/making-the-realforce-87ub-work-with-usb30-on-Ubuntu/
[3]: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1678477
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Nicolas Dumazet <ndumazet@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221109122946.706036-1-ndumazet@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/core/quirks.c | 3 +++
1 file changed, 3 insertions(+)
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -362,6 +362,9 @@ static const struct usb_device_id usb_qu
{ USB_DEVICE(0x0781, 0x5583), .driver_info = USB_QUIRK_NO_LPM },
{ USB_DEVICE(0x0781, 0x5591), .driver_info = USB_QUIRK_NO_LPM },
+ /* Realforce 87U Keyboard */
+ { USB_DEVICE(0x0853, 0x011b), .driver_info = USB_QUIRK_NO_LPM },
+
/* M-Systems Flash Disk Pioneers */
{ USB_DEVICE(0x08ec, 0x1000), .driver_info = USB_QUIRK_RESET_RESUME },
Patches currently in stable-queue which might be from ndumazet@xxxxxxxxxx are
queue-6.0/usb-add-no_lpm-quirk-for-realforce-87u-keyboard.patch
