On Sun, Nov 29, 2015 at 11:00 PM, Alexandre Oliva <[email protected]> wrote:
> On Nov 28, 2015, Alexandre Oliva <[email protected]> wrote: > > > On Nov 28, 2015, Iru Cai <[email protected]> wrote: > >> I bought a Chromebook pixel 2013 recently. When it runs Trisquel with > >> Linux-libre 3.13, the touchscreen and touchpad work fine. However, in > later > >> kernel release, it needs to load non-free firmware in mxt_initialize(), > >> which is in drivers/input/touchscreen/atmel_mxt_ts.c, and the > atmel_mxt_ts > >> driver fails to work. Is there a work around for this? > > > I suspect blacklisting the specific driver might get the device to > > fallback to generic emulation mode, which is presumably what you were > > get on 3.13 (assuming there isn't a specific driver there). > Sorry for not cc the replied mail to the mailing list when I was replying the previous mails. > > I've taken a look at the driver, and it is buggy. Even though it works > without the blob, it treats an -EINVAL return from r*t_firmware_nowait > as a hard error, instead of ignoring as it could/should, to work even > upstream, when the firmware loader is disabled altogether in the build > configuration. > I forgot to mention one thing. The reject_firmware_nowait sometimes causes a kernel panic in atmel_mxt_ts driver. I didn't save the kernel error messages, but I think there may be something wrong with the reject firmware logic. > > We could work around that bug in GNU Linux-libre, using an alternate > call that fakes a success return status, but... I'd much rather it be > fixed upstream, so that we can keep local changes to a minimum. > Would you report that, saying it doesn't work with the firmware loader > disabled, or if request_firmware_nowait fails for whatever reason, even > though you know it could work just fine? > I meant that it works if I changed reject_firmware_nowait to request_firmware_nowait, although the kernel will say it fails to load firmware. It doesn't give a 'Failed to invoke firmware loader.' error. > > In the mean time, I suggest patching the driver so that it doesn't take > the error status from reject_firmware_nowait as fatal, reporting it but > ignoring it. > > -- > Alexandre Oliva, freedom fighter http://FSFLA.org/~lxoliva/ > You must be the change you wish to see in the world. -- Gandhi > Be Free! -- http://FSFLA.org/ FSF Latin America board member > Free Software Evangelist|Red Hat Brasil GNU Toolchain Engineer >
_______________________________________________ linux-libre mailing list [email protected] http://www.fsfla.org/cgi-bin/mailman/listinfo/linux-libre
