From mboxrd@z Thu Jan 1 00:00:00 1970 From: eric.y.miao@gmail.com (Eric Miao) Date: Wed, 7 Apr 2010 10:09:39 +0800 Subject: AC97 problems with pxa... In-Reply-To: <4BBBACBE.7040505@bitsim.com> References: <4BBBACBE.7040505@bitsim.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Apr 7, 2010 at 5:50 AM, Jakob Viketoft wrote: > > Hello! > > I'm trying to add sound support to a Toradex Colibri 270 v2 card, but > have run into some strangeness which I don't quite understand. The v2 of > this card uses the WM9712 codec and I've written a machine driver to tie > the codec and the pxa2xx-ac97 driver together. I'm using the 2.6.33.1 > kernel and my machine driver is a simplified version of the tosa driver > (no power management or headphone jack logic). However, I get two problems: > 1. Internal clock and headphone output is turned off in the > AC97_POWERDOWN register and I can't see where to (properly) turn it on, > neither in kernel space or in userland. No-one else using this codec > seem to be doing it. > 2. The init function defined in my snd_soc_card struct doesn't seem to > get called, resulting in way too many mixer settings (I have a number of > snd_soc_dapm_nc_pin calls) with alsa, but might it also have something > to do with problem 1? > > When explicitly writing 0 (the ugly way) to the AC97_POWERDOWN register > I get perfect sound output, but I would like to do it the right way. > > Two error reports from the dmesg output that might be relevant: > * pxa2xx_ac97_try_cold_reset: cold reset timeout (GSR=0x44) > * Error: Driver 'pxa2xx-ac97' is already registered, aborting... > > The AC97 interface is added in the machine initialization through the > pxa_set_ac97_info() in the same way as tosa and many others and this > could explain the second error message... > > Any insight would be appreciated! > Better if you could come up with a patch or source code for analysis.