[PATCH] ASoC: pcm512x: Mend accesses to the I2S_1 and I2S_2 registers

[Peter Rosin]

>From 625f858894af2b7e547cc723b97361081438b123 Mon Sep 17 00:00:00 2001
From: Peter Rosin <peda at axentia.se>

Commit 25d27c4f68d2 ("ASoC: pcm512x: Add support for more data formats")
breaks the TSE-850 device, which is using a pcm5142 in I2S and
CBM_CFS mode (maybe not relevant). Without this fix, the result
is:

pcm512x 0-004c: Failed to set data format: -16

And after that, no sound.

This fix is not 100% correct. The datasheet of at least the pcm5142
states that four bits (0xcc) in the I2S_1 register are "RSV"
("Reserved. Do not access.") and no hint is given as to what the
initial values are supposed to be. So, specifying defaults for
these bits is wrong. But perhaps better than a broken driver?

Fixes: 25d27c4f68d2 ("ASoC: pcm512x: Add support for more data formats")
Cc: Liam Girdwood <lgirdwood at gmail.com>
Cc: Mark Brown <broonie at kernel.org>
Cc: Jaroslav Kysela <perex at perex.cz>
Cc: Takashi Iwai <tiwai at suse.com>
Cc: Kirill Marinushkin <kmarinushkin at birdec.com>
Cc: Peter Ujfalusi <peter.ujfalusi at ti.com>
Cc: alsa-devel at alsa-project.org
Cc: linux-kernel at vger.kernel.org
Signed-off-by: Peter Rosin <peda at axentia.se>
---
 sound/soc/codecs/pcm512x.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sound/soc/codecs/pcm512x.c b/sound/soc/codecs/pcm512x.c
index 4dc844f3c1fc..60dee41816dc 100644
--- a/sound/soc/codecs/pcm512x.c
+++ b/sound/soc/codecs/pcm512x.c
@@ -116,6 +116,8 @@ static const struct reg_default pcm512x_reg_defaults[] = {
 	{ PCM512x_FS_SPEED_MODE,     0x00 },
 	{ PCM512x_IDAC_1,            0x01 },
 	{ PCM512x_IDAC_2,            0x00 },
+	{ PCM512x_I2S_1,             0x02 },
+	{ PCM512x_I2S_2,             0x00 },
 };
 
 static bool pcm512x_readable(struct device *dev, unsigned int reg)
-- 
2.20.1