[PATCH v2] ASoC: sgtl5000: Fix driver probe after reset

[PATCH v2] ASoC: sgtl5000: Fix driver probe after reset

[Fabio Estevam]

From: Fabio Estevam <fabio.estevam@freescale.com>

sgtl5000 codec does not have a reset line, nor a reset command in software.

After a 'reboot' command in Linux or after pressing the system's reset button
the sgtl5000 driver fails to probe:

sgtl5000 0-000a: Device with ID register ffff is not a sgtl5000
sgtl5000 0-000a: ASoC: failed to probe CODEC -19
imx-sgtl5000 sound.12: ASoC: failed to instantiate card -19
imx-sgtl5000 sound.12: snd_soc_register_card failed (-19)

As the sgtl5000 codec did not go through a real reset, we cannot rely on the 
sgtl5000_reg_defaults array, since these are only valid after a clean power-on 
reset.

To fix this issue, use 'num_reg_defaults_raw' which tells the regcache driver
to actually read the codec registers and then fill the cache with these values.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
---
Changes since v1:
- Remove sgtl5000_reg_defaults array
- Do not use num_reg_defaults_raw

 sound/soc/codecs/sgtl5000.c |   30 +-----------------------------
 1 file changed, 1 insertion(+), 29 deletions(-)

diff --git a/sound/soc/codecs/sgtl5000.c b/sound/soc/codecs/sgtl5000.c
index 327b443..fa342f7 100644
--- a/sound/soc/codecs/sgtl5000.c
+++ b/sound/soc/codecs/sgtl5000.c
@@ -34,33 +34,6 @@
 #define SGTL5000_DAP_REG_OFFSET	0x0100
 #define SGTL5000_MAX_REG_OFFSET	0x013A
 
-/* default value of sgtl5000 registers */
-static const struct reg_default sgtl5000_reg_defaults[] = {
-	{ SGTL5000_CHIP_CLK_CTRL,		0x0008 },
-	{ SGTL5000_CHIP_I2S_CTRL,		0x0010 },
-	{ SGTL5000_CHIP_SSS_CTRL,		0x0008 },
-	{ SGTL5000_CHIP_DAC_VOL,		0x3c3c },
-	{ SGTL5000_CHIP_PAD_STRENGTH,		0x015f },
-	{ SGTL5000_CHIP_ANA_HP_CTRL,		0x1818 },
-	{ SGTL5000_CHIP_ANA_CTRL,		0x0111 },
-	{ SGTL5000_CHIP_LINE_OUT_VOL,		0x0404 },
-	{ SGTL5000_CHIP_ANA_POWER,		0x7060 },
-	{ SGTL5000_CHIP_PLL_CTRL,		0x5000 },
-	{ SGTL5000_DAP_BASS_ENHANCE,		0x0040 },
-	{ SGTL5000_DAP_BASS_ENHANCE_CTRL,	0x051f },
-	{ SGTL5000_DAP_SURROUND,		0x0040 },
-	{ SGTL5000_DAP_EQ_BASS_BAND0,		0x002f },
-	{ SGTL5000_DAP_EQ_BASS_BAND1,		0x002f },
-	{ SGTL5000_DAP_EQ_BASS_BAND2,		0x002f },
-	{ SGTL5000_DAP_EQ_BASS_BAND3,		0x002f },
-	{ SGTL5000_DAP_EQ_BASS_BAND4,		0x002f },
-	{ SGTL5000_DAP_MAIN_CHAN,		0x8000 },
-	{ SGTL5000_DAP_AVC_CTRL,		0x0510 },
-	{ SGTL5000_DAP_AVC_THRESHOLD,		0x1473 },
-	{ SGTL5000_DAP_AVC_ATTACK,		0x0028 },
-	{ SGTL5000_DAP_AVC_DECAY,		0x0050 },
-};
-
 /* regulator supplies for sgtl5000, VDDD is an optional external supply */
 enum sgtl5000_regulator_supplies {
 	VDDA,
@@ -1470,8 +1443,7 @@ static const struct regmap_config sgtl5000_regmap = {
 	.readable_reg = sgtl5000_readable,
 
 	.cache_type = REGCACHE_RBTREE,
-	.reg_defaults = sgtl5000_reg_defaults,
-	.num_reg_defaults = ARRAY_SIZE(sgtl5000_reg_defaults),
+	.num_reg_defaults_raw = SGTL5000_MAX_REG_OFFSET,
 };
 
 static int sgtl5000_i2c_probe(struct i2c_client *client,
-- 
1.7.9.5

Re: [PATCH v2] ASoC: sgtl5000: Fix driver probe after reset

[Mark Brown]

[-- Attachment #1.1: Type: text/plain, Size: 998 bytes --]

On Wed, May 08, 2013 at 05:45:55PM -0300, Fabio Estevam wrote:

> As the sgtl5000 codec did not go through a real reset, we cannot rely on the 
> sgtl5000_reg_defaults array, since these are only valid after a clean power-on 
> reset.

> To fix this issue, use 'num_reg_defaults_raw' which tells the regcache driver
> to actually read the codec registers and then fill the cache with these values.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
> ---
> Changes since v1:
> - Remove sgtl5000_reg_defaults array
> - Do not use num_reg_defaults_raw

Changelog update needed here :)

I'm not sure that removing the defaults is the ideal thing here - it
means that the driver will be stuck with whatever the last booted OS
left the device running which may or may not be sane.  Explicitly
writing in all the values we want seems safer, that way we know how the
device is configured and there's less potential for odd bugs caused by
rebooting at the wrong moment.

[-- Attachment #1.2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

[-- Attachment #2: Type: text/plain, Size: 0 bytes --]

Re: [PATCH v2] ASoC: sgtl5000: Fix driver probe after reset

[Mark Brown]

[-- Attachment #1.1: Type: text/plain, Size: 569 bytes --]

On Thu, May 09, 2013 at 12:08:38PM -0500, Matt Sealey wrote:

> match a reset chip powered on for the first time. What we should
> actually be doing is dumping these into the chip as the first thing we
> do at probe, and then they DO become the reasonable defaults.

Yes, this is eactly what I keep saying :/

> The fix is keep using cache/regmaps or whatever, but it definitely
> would be an absolute requirement to reset the codec manually by
> putting in all the right register values before using the cache, which

You don't need to disable the cache at any point.

[-- Attachment #1.2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

[-- Attachment #2: Type: text/plain, Size: 0 bytes --]