Re: [PATCH] HID: rmi: Check that a device is a RMI device before calling RMI functions

[Jiri Kosina]

On Wed, 18 Oct 2017, Benjamin Tissoires wrote:

> > The hid-rmi driver may handle non rmi devices on composite USB devices.
> > Callbacks need to make sure that the current device is a RMI device before
> > calling RMI specific functions. Most callbacks already have this check, but
> > this patch adds checks to the remaining callbacks.
> > 
> > Signed-off-by: Andrew Duggan <aduggan@xxxxxxxxxxxxx>
> > ---
> > This is the patch which hopefully will address the X1 tablet dock freeze:
> > http://www.spinics.net/lists/linux-input/msg53582.html
> > 
> > I was not able to test on a composite USB device so I have not tested confirmed
> > this will fix the reported issues. But, based on the description I think it will.
> > I also added a check for rmi_raw_event() since it could be possible that another
> > hid device using one of the same report IDs as an RMI device could result in calling
> > into unitialized RMI functions. It was also the only callbacl left not checking the
> > RMI_DEVICE flag. I wonder if this explains the attach crash.
> > 
> > Anyway, I would appriciate it if Hendrik or someone else with the device could test this
> > patch to confirm it fixes the reported behavior.
> 
> Shouldn't rmi_hid_reset() also get the same check?

I think so as well.

> 
> From what I can see, even if the patch doesn't fix the immediate issue, 
> such a patch should definitively go in as those checks are clearly 
> missing.

Agreed; however I'd like to get Hendrik's Tested-by: if possible in case 
this really fixes the issue, so I am not merging it right away.

Hendrik, are you by any chance able to test this patch in a reasonable 
timeframe please?

Thanks!

-- 
Jiri Kosina
SUSE Labs