HID: Revert "Revert "HID: Fix logitech-dj: missing Unifying device issue""
This reverts commit 8af6c088. This patch re-adds the workaround introduced by 59626408 which was reverted by 8af6c088. The original patch 596264 was needed to overcome a situation where the hid-core would drop incoming reports while probe() was being executed. This issue was solved by c849a614 which added hid_device_io_start() and hid_device_io_stop() that enable a specific hid driver to opt-in for input reports while its probe() is being executed. Commit a9dd22b7 modified hid-logitech-dj so as to use the functionality added to hid-core. Having done that, workaround 596264 was no longer necessary and was reverted by 8af6c088. We now encounter a different problem that ends up 'again' thwarting the Unifying receiver enumeration. The problem is time and usb controller dependent. Ocasionally the reports sent to the usb receiver to start the paired devices enumeration fail with -EPIPE and the receiver never gets to enumerate the paired devices. With dcd9006b the problem was "hidden" as the call to the usb driver became asynchronous and none was catching the error from the failing URB. As the root cause for this failing SET_REPORT is not understood yet, -possibly a race on the usb controller drivers or a problem with the Unifying receiver- reintroducing this workaround solves the problem. Overall what this workaround does is: If an input report from an unknown device is received, then a (re)enumeration is performed. related bug: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1194649 Signed-off-by:Nestor Lopez Casado <nlopezcasad@logitech.com> Signed-off-by:
Jiri Kosina <jkosina@suse.cz>
parent
3366dd9f
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