2020-08-28 15:18:20

by Jerome Brunet

[permalink] [raw]
Subject: [PATCH] ASoC: meson: axg-toddr: fix channel order on g12 platforms

On g12 and following platforms, The first channel of record with more than
2 channels ends being placed randomly on an even channel of the output.

On these SoCs, a bit was added to force the first channel to be placed at
the beginning of the output. Apparently the behavior if the bit is not set
is not easily predictable. According to the documentation, this bit is not
present on the axg series.

Set the bit on g12 and fix the problem.

Fixes: a3c23a8ad4dc ("ASoC: meson: axg-toddr: add g12a support")
Reported-by: Nicolas Belin <[email protected]>
Signed-off-by: Jerome Brunet <[email protected]>
---
sound/soc/meson/axg-toddr.c | 24 +++++++++++++++++++++++-
1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/sound/soc/meson/axg-toddr.c b/sound/soc/meson/axg-toddr.c
index e711abcf8c12..d6adf7edea41 100644
--- a/sound/soc/meson/axg-toddr.c
+++ b/sound/soc/meson/axg-toddr.c
@@ -18,6 +18,7 @@
#define CTRL0_TODDR_SEL_RESAMPLE BIT(30)
#define CTRL0_TODDR_EXT_SIGNED BIT(29)
#define CTRL0_TODDR_PP_MODE BIT(28)
+#define CTRL0_TODDR_SYNC_CH BIT(27)
#define CTRL0_TODDR_TYPE_MASK GENMASK(15, 13)
#define CTRL0_TODDR_TYPE(x) ((x) << 13)
#define CTRL0_TODDR_MSB_POS_MASK GENMASK(12, 8)
@@ -189,10 +190,31 @@ static const struct axg_fifo_match_data axg_toddr_match_data = {
.dai_drv = &axg_toddr_dai_drv
};

+static int g12a_toddr_dai_startup(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ struct axg_fifo *fifo = snd_soc_dai_get_drvdata(dai);
+ int ret;
+
+ ret = axg_toddr_dai_startup(substream, dai);
+ if (ret)
+ return ret;
+
+ /*
+ * Make sure the first channel ends up in the at beginning of the output
+ * As weird as it looks, without this the first channel may be misplaced
+ * in memory, with a random shift of 2 channels.
+ */
+ regmap_update_bits(fifo->map, FIFO_CTRL0, CTRL0_TODDR_SYNC_CH,
+ CTRL0_TODDR_SYNC_CH);
+
+ return 0;
+}
+
static const struct snd_soc_dai_ops g12a_toddr_ops = {
.prepare = g12a_toddr_dai_prepare,
.hw_params = axg_toddr_dai_hw_params,
- .startup = axg_toddr_dai_startup,
+ .startup = g12a_toddr_dai_startup,
.shutdown = axg_toddr_dai_shutdown,
};

--
2.25.4


2020-08-28 18:06:00

by Mark Brown

[permalink] [raw]
Subject: Re: [PATCH] ASoC: meson: axg-toddr: fix channel order on g12 platforms

On Fri, 28 Aug 2020 17:14:38 +0200, Jerome Brunet wrote:
> On g12 and following platforms, The first channel of record with more than
> 2 channels ends being placed randomly on an even channel of the output.
>
> On these SoCs, a bit was added to force the first channel to be placed at
> the beginning of the output. Apparently the behavior if the bit is not set
> is not easily predictable. According to the documentation, this bit is not
> present on the axg series.
>
> [...]

Applied to

https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next

Thanks!

[1/1] ASoC: meson: axg-toddr: fix channel order on g12 platforms
commit: 9c4b205a20f483d8a5d1208cfec33e339347d4bd

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark