[PATCH AUTOSEL 5.3 096/203] ASoC: uniphier: Fix double reset assersion when transitioning to suspend state

Sasha Levin
2019-09-22T19:35:26Z

From: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>

[ Upstream commit c372a35550c8d60f673b20210eea58a06d6d38cb ]

When transitioning to supend state, uniphier_aio_dai_suspend() is called
and asserts reset lines and disables clocks.

However, if there are two or more DAIs, uniphier_aio_dai_suspend() are
called multiple times, and double reset assersion will cause.

This patch defines the counter that has the number of DAIs at first, and
whenever uniphier_aio_dai_suspend() are called, it decrements the
counter. And only if the counter is zero, it asserts reset lines and
disables clocks.

In the same way, uniphier_aio_dai_resume() are called, it increments the
counter after deasserting reset lines and enabling clocks.

Fixes: 139a34200233 ("ASoC: uniphier: add support for UniPhier AIO CPU DAI driver")
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Link: https://lore.kernel.org/r/1566281764-14059-1-git-send-email-hayashi.kunihiko@socionext.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
sound/soc/uniphier/aio-cpu.c | 31 +++++++++++++++++++++----------
sound/soc/uniphier/aio.h | 1 +
2 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/sound/soc/uniphier/aio-cpu.c b/sound/soc/uniphier/aio-cpu.c
index ee90e6c3937ce..2ae582a99b636 100644
--- a/sound/soc/uniphier/aio-cpu.c
+++ b/sound/soc/uniphier/aio-cpu.c
@@ -424,8 +424,11 @@ int uniphier_aio_dai_suspend(struct snd_soc_dai *dai)
{
struct uniphier_aio *aio = uniphier_priv(dai);

- reset_control_assert(aio->chip->rst);
- clk_disable_unprepare(aio->chip->clk);
+ aio->chip->num_wup_aios--;
+ if (!aio->chip->num_wup_aios) {
+ reset_control_assert(aio->chip->rst);
+ clk_disable_unprepare(aio->chip->clk);
+ }

return 0;
}
@@ -439,13 +442,15 @@ int uniphier_aio_dai_resume(struct snd_soc_dai *dai)
if (!aio->chip->active)
return 0;

- ret = clk_prepare_enable(aio->chip->clk);
- if (ret)
- return ret;
+ if (!aio->chip->num_wup_aios) {
+ ret = clk_prepare_enable(aio->chip->clk);
+ if (ret)
+ return ret;

- ret = reset_control_deassert(aio->chip->rst);
- if (ret)
- goto err_out_clock;
+ ret = reset_control_deassert(aio->chip->rst);
+ if (ret)
+ goto err_out_clock;
+ }

aio_iecout_set_enable(aio->chip, true);
aio_chip_init(aio->chip);
@@ -458,7 +463,7 @@ int uniphier_aio_dai_resume(struct snd_soc_dai *dai)

ret = aio_init(sub);
if (ret)
- goto err_out_clock;
+ goto err_out_reset;

if (!sub->setting)
continue;
@@ -466,11 +471,16 @@ int uniphier_aio_dai_resume(struct snd_soc_dai *dai)
aio_port_reset(sub);
aio_src_reset(sub);
}
+ aio->chip->num_wup_aios++;

return 0;

+err_out_reset:
+ if (!aio->chip->num_wup_aios)
+ reset_control_assert(aio->chip->rst);
err_out_clock:
- clk_disable_unprepare(aio->chip->clk);
+ if (!aio->chip->num_wup_aios)
+ clk_disable_unprepare(aio->chip->clk);

return ret;
}
@@ -619,6 +629,7 @@ int uniphier_aio_probe(struct platform_device *pdev)
return PTR_ERR(chip->rst);

chip->num_aios = chip->chip_spec->num_dais;
+ chip->num_wup_aios = chip->num_aios;
chip->aios = devm_kcalloc(dev,
chip->num_aios, sizeof(struct uniphier_aio),
GFP_KERNEL);
diff --git a/sound/soc/uniphier/aio.h b/sound/soc/uniphier/aio.h
index ca6ccbae0ee8c..a7ff7e556429b 100644
--- a/sound/soc/uniphier/aio.h
+++ b/sound/soc/uniphier/aio.h
@@ -285,6 +285,7 @@ struct uniphier_aio_chip {

struct uniphier_aio *aios;
int num_aios;
+ int num_wup_aios;
struct uniphier_aio_pll *plls;
int num_plls;

--
2.20.1