diff options
| author | Jason Wessel <[email protected]> | 2009-08-20 15:39:56 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <[email protected]> | 2009-09-23 06:46:38 -0700 |
| commit | 68d2956a810b5c1b8213a1a9f59eacc54d7ce087 (patch) | |
| tree | ce63aa5c1580b217af7ddd21fecee7cd2cca6c77 /tools/perf/scripts/python | |
| parent | aab2d4086a1876fcff282aa36e2d4a92aa9935c9 (diff) | |
USB: ehci-dbgp: errata for EHCI debug/host controller synchronization
On some EHCI debug controllers after the host controller driver is
activated, the debug controller will occasionally fail to submit a
bulk write URB. On controllers that exhibit this behavior a dummy
bulk write must get submitted to resynchronize the device.
The "dummy bulk write" does not get received by the host attached to
the other end of the usb debug device. The usb debug device simply
acknowledges the "dummy bulk write" and returns to a usable state.
The behavior, without this patch is that you see missing text from a
complete kernel boot when using the keep option to the earlyprintk
kernel argument.
Signed-off-by: Jason Wessel <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Yinghai Lu <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Diffstat (limited to 'tools/perf/scripts/python')
0 files changed, 0 insertions, 0 deletions