On Mon, Jul 20, 2015 at 03:26:40PM -0700, Dmitry Torokhov wrote:

On Mon, Jul 20, 2015 at 02:59:56PM -0700, Greg KH wrote:

quoted

On Mon, Jul 20, 2015 at 11:03:19PM +0200, Yann Cantin wrote:

quoted

Signed-off-by: Yann Cantin <redacted>

quoted

+
+	/* sysfs setup */
+	err = sysfs_create_group(&intf->dev.kobj, &ebeam_attr_group);

Ick, you just added the sysfs files to the USB device, not your input
device, are you sure you tested this?

And there should be a race-free way to add an attribute group to an
input device, as this is, you are adding them to the device _after_ it
is created, so userspace will not see them at creation time, causing a
race.

No, there are no driver-specific attributed on input devices themselves,
they belong to the actual hardware devices. The input devices only
export standard attributes applicable to every and all input devices
in the system.

Then the Documentation in this patch better be fixed up, as it points to
the input device as having these sysfs files :)

But as these are input device attributes, and not USB device interface
attributes, putting them on the USB interface doesn't make much sense,
and as I pointed out, is racy.  Why can't input devices have
driver-specific attributes?  Why does input devices add their own
attributes sometimes (like in psmouse, which does so in a racy way) yet
this driver shouldn't do that?

Hm, nevermind about psmouse, that happens on the parent device too it
seems (a serio device), not the input device, so it is "consistent", but
not something I really like...

thanks,

greg k-h