[PATCH 2/2] ARM: dts: mx28: Fix sgtl5000 codec probe

[Shawn Guo]

On Mon, Jun 24, 2013 at 11:18:52AM -0300, Fabio Estevam wrote:
> On Mon, Jun 24, 2013 at 11:07 AM, Shawn Guo <shawn.guo at linaro.org> wrote:
> > On Mon, Jun 24, 2013 at 10:54:11AM -0300, Fabio Estevam wrote:
> >> On Mon, Jun 24, 2013 at 4:29 AM, Shawn Guo <shawn.guo at linaro.org> wrote:
> >>
> >> > Yes, we should have sgtl5000 acquire its clock, but when it fails to do
> >> > so, there is nothing wrong with deferring it to see if mxs-saif would
> >> > provide the clock later.
> >>
> >> I didn't manage to get mx28evk to probe audio correctly by using -EPROBE_DEFER.
> >
> > When you was doing that, did you have the clock that sgtl5000 is
> > requesting registered somewhere?
> 
> I registered it as dummy one (same as done in this patch).
> 
> Then regmap_read fails (from sgtl5000 driver), as it tries to read the
> codec revision via I2C and the clock is not available yet. Then I
> changed to return a -EDEFER_PROBE in case of failure:
> 
> [    1.754258] mxs-lradc 80050000.lradc: Touchscreen not enabled.
> [    1.783755] ******* reading I2C failed
> [    1.789748] i2c 0-000a: Driver sgtl5000 requests probe deferral
> [    1.801720] mxs-sgtl5000 sound.12: ASoC: CODEC (null) not registered
> [    1.809608] mxs-sgtl5000 sound.12: snd_soc_register_card failed (-517)
> [    1.816675] platform sound.12: Driver mxs-sgtl5000 requests probe deferral
> [    1.825852] TCP: cubic registered
> [    1.829375] NET: Registered protocol family 17
> [    1.835999] Key type dns_resolver registered
> [    1.844549] mmc0: new SDHC card at address f955
> [    1.852887] registered taskstats version 1
> [    1.860535] mmcblk0: mmc0:f955 SD04G 3.69 GiB
> [    1.878653] sgtl5000 0-000a: sgtl5000 revision 0x11

Oh, look at this line, you have the clock work for sgtl5000.  So it
seems that sgtl5000_i2c_probe() fails at somewhere else on the second
try.

Shawn

> [    1.887430]  mmcblk0: p1 p2 p3
> [    1.894824] mxs-sgtl5000 sound.12: ASoC: CODEC (null) not registered
> [    1.901468] mxs-sgtl5000 sound.12: snd_soc_register_card failed (-517)
> 
> Then it succeeds in the following attemp, but snd_soc_register_card() fails.