usb: Enable LPM for USB 2.01+ full-speed devices
Hi Rupesh,
A kernel bug report was opened against Ubuntu [0]. After a kernel bisect, it was found that reverting the following commit resolved this bug:
commit a8425292816ceaa8c49e29d2114e85d85a73e080
Author: Rupesh Tatiya <[email protected]> Date: Tue Apr 14 16:36:55 2015 +0530
usb: Enable LPM for USB 2.01+ full-speed devices
The regression was introduced as of v4.2-rc1.
I was hoping to get your feedback, since you are the patch author. Do you think gathering any additional data will help diagnose this issue, or would it be best to submit a revert request?
Thanks,
Joe
Quoted 9 lines · Joseph Salisbury
Hi Rupesh,
A kernel bug report was opened against Ubuntu [0]. After a kernel bisect, it was found that reverting the following commit resolved this bug:
commit
a8425292816ceaa8c49e29d2114e85d85a73e080Author: Rupesh Tatiya <[email protected]> Date: Tue Apr 14 16:36:55 2015 +0530
Quoted 8 lines
usb: Enable LPM for USB 2.01+ full-speed devices
The regression was introduced as of v4.2-rc1.
I was hoping to get your feedback, since you are the patch author. Do you think gathering any additional data will help diagnose this issue, or would it be best to submit a revert request?
Does the problem still happen with 4.7-rc4 or even 4.6?
4.2 is pretty old and obsolete you know :)
thanks,
greg k-h
Quoted 9 lines · Joseph Salisbury
Hi Rupesh,
A kernel bug report was opened against Ubuntu [0]. After a kernel bisect, it was found that reverting the following commit resolved this bug:
commit
a8425292816ceaa8c49e29d2114e85d85a73e080Author: Rupesh Tatiya <[email protected]> Date: Tue Apr 14 16:36:55 2015 +0530
Quoted 8 lines
usb: Enable LPM for USB 2.01+ full-speed devices
The regression was introduced as of v4.2-rc1.
I was hoping to get your feedback, since you are the patch author. Do you think gathering any additional data will help diagnose this issue, or would it be best to submit a revert request?
Another option is to add a NO_LPM quirks entry for the troublesome device.
Alan Stern
Quoted 18 lines · Greg KH
Quoted 9 lines · Joseph Salisbury
Hi Rupesh,
A kernel bug report was opened against Ubuntu [0]. After a kernel bisect, it was found that reverting the following commit resolved this bug:
commit
a8425292816ceaa8c49e29d2114e85d85a73e080Author: Rupesh Tatiya <[email protected]> Date: Tue Apr 14 16:36:55 2015 +0530Quoted 8 lines
usb: Enable LPM for USB 2.01+ full-speed devices
The regression was introduced as of v4.2-rc1.
I was hoping to get your feedback, since you are the patch author. Do you think gathering any additional data will help diagnose this issue, or would it be best to submit a revert request?
Quoted 7 lines
Does the problem still happen with 4.7-rc4 or even 4.6?
4.2 is pretty old and obsolete you know :)
thanks,
greg k-h
The regression does exist in 4.6-rc2. I'll have the latest mainline 4.7-rc4 kernel tested.
Quoted 21 lines · Joseph Salisbury
Quoted 20 lines · Greg KH
Quoted 9 lines · Joseph Salisbury
Hi Rupesh,
A kernel bug report was opened against Ubuntu [0]. After a kernel bisect, it was found that reverting the following commit resolved this bug:
commit
a8425292816ceaa8c49e29d2114e85d85a73e080Author: Rupesh Tatiya <[email protected]> Date: Tue Apr 14 16:36:55 2015 +0530Quoted 8 lines
usb: Enable LPM for USB 2.01+ full-speed devices
The regression was introduced as of v4.2-rc1.
I was hoping to get your feedback, since you are the patch author. Do you think gathering any additional data will help diagnose this issue, or would it be best to submit a revert request?
Does the problem still happen with 4.7-rc4 or even 4.6?
Quoted 7 lines
Quoted 5 lines
4.2 is pretty old and obsolete you know :)
thanks,
greg k-h
The regression does exist in 4.6-rc2. I'll have the latest mainline 4.7-rc4 kernel tested.
The 4.7-rc4 kernel still exhibits the bug.
Quoted 22 lines · Joseph Salisbury
Quoted 21 lines · Joseph Salisbury
Quoted 20 lines · Greg KH
Quoted 9 lines · Joseph Salisbury
Hi Rupesh,
A kernel bug report was opened against Ubuntu [0]. After a kernel bisect, it was found that reverting the following commit resolved this bug:
commit
a8425292816ceaa8c49e29d2114e85d85a73e080Author: Rupesh Tatiya <[email protected]> Date: Tue Apr 14 16:36:55 2015 +0530Quoted 8 lines
usb: Enable LPM for USB 2.01+ full-speed devices
The regression was introduced as of v4.2-rc1.
I was hoping to get your feedback, since you are the patch author. Do you think gathering any additional data will help diagnose this issue, or would it be best to submit a revert request?
Does the problem still happen with 4.7-rc4 or even 4.6?
Quoted 8 lines
Quoted 7 lines
Quoted 5 lines
4.2 is pretty old and obsolete you know :)
thanks,
greg k-h
The regression does exist in 4.6-rc2. I'll have the latest mainline 4.7-rc4 kernel tested.
The 4.7-rc4 kernel still exhibits the bug.
Have you tried adding a NO_LPM quirk entry for this device, as I suggested in an earlier email? I can write a patch for this, if you want.
Alan Stern
Quoted 29 lines · Alan Stern
Quoted 27 lines · Joseph Salisbury
Quoted 26 lines · Joseph Salisbury
Quoted 25 lines · Greg KH
Quoted 9 lines · Joseph Salisbury
Hi Rupesh,
A kernel bug report was opened against Ubuntu [0]. After a kernel bisect, it was found that reverting the following commit resolved this bug:
commit
a8425292816ceaa8c49e29d2114e85d85a73e080Author: Rupesh Tatiya <[email protected]> Date: Tue Apr 14 16:36:55 2015 +0530Quoted 8 lines
usb: Enable LPM for USB 2.01+ full-speed devices
The regression was introduced as of v4.2-rc1.
I was hoping to get your feedback, since you are the patch author. Do you think gathering any additional data will help diagnose this issue, or would it be best to submit a revert request?
Does the problem still happen with 4.7-rc4 or even 4.6?
4.2 is pretty old and obsolete you know :)
thanks,
greg k-h
Quoted 9 lines
Quoted 3 lines
Quoted 2 lines
The regression does exist in 4.6-rc2. I'll have the latest mainline 4.7-rc4 kernel tested.
The 4.7-rc4 kernel still exhibits the bug.
Have you tried adding a
NO_LPMquirk entry for this device, as I suggested in an earlier email? I can write a patch for this, if you want.Alan Stern
Thanks for the suggesting, Alan. I'll give this a try and reply with the result.
Quoted 29 lines · Alan Stern
Quoted 27 lines · Joseph Salisbury
Quoted 26 lines · Joseph Salisbury
Quoted 25 lines · Greg KH
Quoted 9 lines · Joseph Salisbury
Hi Rupesh,
A kernel bug report was opened against Ubuntu [0]. After a kernel bisect, it was found that reverting the following commit resolved this bug:
commit
a8425292816ceaa8c49e29d2114e85d85a73e080Author: Rupesh Tatiya <[email protected]> Date: Tue Apr 14 16:36:55 2015 +0530Quoted 8 lines
usb: Enable LPM for USB 2.01+ full-speed devices
The regression was introduced as of v4.2-rc1.
I was hoping to get your feedback, since you are the patch author. Do you think gathering any additional data will help diagnose this issue, or would it be best to submit a revert request?
Does the problem still happen with 4.7-rc4 or even 4.6?
4.2 is pretty old and obsolete you know :)
thanks,
greg k-h
Quoted 9 lines
Quoted 3 lines
Quoted 2 lines
The regression does exist in 4.6-rc2. I'll have the latest mainline 4.7-rc4 kernel tested.
The 4.7-rc4 kernel still exhibits the bug.
Have you tried adding a
NO_LPMquirk entry for this device, as I suggested in an earlier email? I can write a patch for this, if you want.Alan Stern
Yes, adding a NO_LPM quirk entry resolves the bug. I'll submit a patch shortly, it is basically these lines added to usb_quirk_list[]:
+ /* ELAN Microelectronics Touchscreen */
+ { USB_DEVICE(0x04f3, 0x0381), .driver_info = USB_QUIRK_NO_LPM },
Thanks for the suggestion, Alan!