Hi Dmitry,

I am sorry for getting back to you so late. See below.

On Sat, Apr 21, 2012 at 2:21 PM, Dmitry Torokhov
[off-list ref] wrote:

On Tue, Feb 14, 2012 at 11:18:38AM +0800, Daniel Kurtz wrote:

quoted

On Wed, Feb 8, 2012 at 11:24 AM, Che-Liang Chiou [off-list ref] wrote:

quoted

The serio_raw driver is designed to provide "raw access" to mice, keyboards
etc; thus, a driver accessing serio_raw may live entirely in userland.

However, serio_raw lacks testability.  It is practically impossible to do
regression tests on changes to a serio_raw -based userland driver.  On the other
hand, the kernel's input subsystem has good testability support.  With the help
of tools like utouch-evemu, we may capture and replay input events for evdev
drivers in regression tests.

This patchset contains extensions to the serio_raw driver which add debugfs
entries for monitoring and replaying byte sequence between a userland driver
and device.  These byte sequences can be used in regression tests of the
userland driver.  This patchset closes the gap between serio_raw and the input
subsystem regarding testability.

This patchset is successfully applied on kernel version 3.3-rc2.

Che-Liang Chiou (5):
 Input: serio_raw - return proper result when serio_raw_read fails
 Input: serio_raw - extract queue interface
 Input: serio_raw - factor out common pattern of write
 Input: serio_raw - add debugfs interface
 Input: serio_raw - implement debugfs interface

For patches 3-5:
Reviewed-by: Daniel Kurtz <redacted>

For patch 1 (and its implication on queue_read() in patch 2, I'd
prefer to hear feedback from the list.

I have already taken the patch 1, but I am unsure why we need kernel
support for the monitor and replay. It seems you should only need a
userspace program that would sit between the driver being tested and
serio_raw misc device and pipe data back and forth, optionally saving
it for subsequent replay.

Sadly some user space drivers hard codes path, like
"/dev/serio_raw%d", and quite often their source codes are not
available; so it is effectively impossible to monitor these drivers
without kernel's help.

Besides, changing from accessing a char device to communicating
through IPC requires rewriting the user space driver, no matter it's a
pair of named pipes or a socket. This may sometimes be quite hard
depending on the I/O strategy of the driver.

Thanks.

--
Dmitry

Regards,
Che-Liang