[PATCH 0/2] ASoC: cs42l42: Fixes to power-down

[PATCH 0/2] ASoC: cs42l42: Fixes to power-down

[Richard Fitzgerald]

Driver probe and remove were inconsistent in what they did to power-down
and neither did all steps. In addition to that, neither function
prevented the interrupt handler from running during and after power-down.

Richard Fitzgerald (2):
  ASoC: cs42l42: Reset and power-down on remove() and failed probe()
  ASoC: cs42l42: free_irq() before powering-down on probe() fail

 sound/soc/codecs/cs42l42.c | 43 +++++++++++++++++++++++++++++++------------
 1 file changed, 31 insertions(+), 12 deletions(-)

-- 
2.11.0

[PATCH 1/2] ASoC: cs42l42: Reset and power-down on remove() and failed probe()

[Richard Fitzgerald]

Driver remove() should assert RESET and disable the supplies.

probe() fail was disabling supplies but it didn't assert reset or
put the codec into a power-down state.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
 sound/soc/codecs/cs42l42.c | 24 ++++++++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/sound/soc/codecs/cs42l42.c b/sound/soc/codecs/cs42l42.c
index a8fff274ec63..dc12842ee6e1 100644
--- a/sound/soc/codecs/cs42l42.c
+++ b/sound/soc/codecs/cs42l42.c
@@ -2067,7 +2067,7 @@ static int cs42l42_i2c_probe(struct i2c_client *i2c_client,
 		"reset", GPIOD_OUT_LOW);
 	if (IS_ERR(cs42l42->reset_gpio)) {
 		ret = PTR_ERR(cs42l42->reset_gpio);
-		goto err_disable;
+		goto err_disable_noreset;
 	}
 
 	if (cs42l42->reset_gpio) {
@@ -2111,7 +2111,7 @@ static int cs42l42_i2c_probe(struct i2c_client *i2c_client,
 	ret = regmap_read(cs42l42->regmap, CS42L42_REVID, &reg);
 	if (ret < 0) {
 		dev_err(&i2c_client->dev, "Get Revision ID failed\n");
-		goto err_disable;
+		goto err_shutdown;
 	}
 
 	dev_info(&i2c_client->dev,
@@ -2136,7 +2136,7 @@ static int cs42l42_i2c_probe(struct i2c_client *i2c_client,
 
 	ret = cs42l42_handle_device_data(&i2c_client->dev, cs42l42);
 	if (ret != 0)
-		goto err_disable;
+		goto err_shutdown;
 
 	/* Setup headset detection */
 	cs42l42_setup_hs_type_detect(cs42l42);
@@ -2148,10 +2148,18 @@ static int cs42l42_i2c_probe(struct i2c_client *i2c_client,
 	ret = devm_snd_soc_register_component(&i2c_client->dev,
 			&soc_component_dev_cs42l42, &cs42l42_dai, 1);
 	if (ret < 0)
-		goto err_disable;
+		goto err_shutdown;
+
 	return 0;
 
+err_shutdown:
+	regmap_write(cs42l42->regmap, CS42L42_CODEC_INT_MASK, 0xff);
+	regmap_write(cs42l42->regmap, CS42L42_TSRS_PLUG_INT_MASK, 0xff);
+	regmap_write(cs42l42->regmap, CS42L42_PWR_CTL1, 0xff);
+
 err_disable:
+	gpiod_set_value_cansleep(cs42l42->reset_gpio, 0);
+err_disable_noreset:
 	regulator_bulk_disable(ARRAY_SIZE(cs42l42->supplies),
 				cs42l42->supplies);
 	return ret;
@@ -2164,6 +2172,14 @@ static int cs42l42_i2c_remove(struct i2c_client *i2c_client)
 	if (i2c_client->irq)
 		devm_free_irq(&i2c_client->dev, i2c_client->irq, cs42l42);
 
+	/*
+	 * The driver might not have control of reset and power supplies,
+	 * so ensure that the chip internals are powered down.
+	 */
+	regmap_write(cs42l42->regmap, CS42L42_CODEC_INT_MASK, 0xff);
+	regmap_write(cs42l42->regmap, CS42L42_TSRS_PLUG_INT_MASK, 0xff);
+	regmap_write(cs42l42->regmap, CS42L42_PWR_CTL1, 0xff);
+
 	gpiod_set_value_cansleep(cs42l42->reset_gpio, 0);
 	regulator_bulk_disable(ARRAY_SIZE(cs42l42->supplies), cs42l42->supplies);
 
-- 
2.11.0

[PATCH 2/2] ASoC: cs42l42: free_irq() before powering-down on probe() fail

[Richard Fitzgerald]

Relying on devm to free the irq handler on probe failure leaves a
small window of opportunity for an interrupt to become pending and
then the handler to run after the chip has been reset and powered
off.

For safety cs42l42_probe() should free the irq in the error path.
As the irq is now disabled by the driver in probe() and remove()
there is no point allocating it as a devres-managed item, so
convert to plain non-devres.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
 sound/soc/codecs/cs42l42.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/sound/soc/codecs/cs42l42.c b/sound/soc/codecs/cs42l42.c
index dc12842ee6e1..1029f6b3eb48 100644
--- a/sound/soc/codecs/cs42l42.c
+++ b/sound/soc/codecs/cs42l42.c
@@ -2078,17 +2078,16 @@ static int cs42l42_i2c_probe(struct i2c_client *i2c_client,
 
 	/* Request IRQ if one was specified */
 	if (i2c_client->irq) {
-		ret = devm_request_threaded_irq(&i2c_client->dev,
-						i2c_client->irq,
-						NULL, cs42l42_irq_thread,
-						IRQF_ONESHOT | IRQF_TRIGGER_LOW,
-						"cs42l42", cs42l42);
+		ret = request_threaded_irq(i2c_client->irq,
+					   NULL, cs42l42_irq_thread,
+					   IRQF_ONESHOT | IRQF_TRIGGER_LOW,
+					   "cs42l42", cs42l42);
 		if (ret == -EPROBE_DEFER) {
-			goto err_disable;
+			goto err_disable_noirq;
 		} else if (ret != 0) {
 			dev_err(&i2c_client->dev,
 				"Failed to request IRQ: %d\n", ret);
-			goto err_disable;
+			goto err_disable_noirq;
 		}
 	}
 
@@ -2158,6 +2157,10 @@ static int cs42l42_i2c_probe(struct i2c_client *i2c_client,
 	regmap_write(cs42l42->regmap, CS42L42_PWR_CTL1, 0xff);
 
 err_disable:
+	if (i2c_client->irq)
+		free_irq(i2c_client->irq, cs42l42);
+
+err_disable_noirq:
 	gpiod_set_value_cansleep(cs42l42->reset_gpio, 0);
 err_disable_noreset:
 	regulator_bulk_disable(ARRAY_SIZE(cs42l42->supplies),
@@ -2170,7 +2173,7 @@ static int cs42l42_i2c_remove(struct i2c_client *i2c_client)
 	struct cs42l42_private *cs42l42 = i2c_get_clientdata(i2c_client);
 
 	if (i2c_client->irq)
-		devm_free_irq(&i2c_client->dev, i2c_client->irq, cs42l42);
+		free_irq(i2c_client->irq, cs42l42);
 
 	/*
 	 * The driver might not have control of reset and power supplies,
-- 
2.11.0

Re: [PATCH 0/2] ASoC: cs42l42: Fixes to power-down

[Mark Brown]

On Tue, 26 Oct 2021 13:57:20 +0100, Richard Fitzgerald wrote:
> Driver probe and remove were inconsistent in what they did to power-down
> and neither did all steps. In addition to that, neither function
> prevented the interrupt handler from running during and after power-down.
> 
> Richard Fitzgerald (2):
>   ASoC: cs42l42: Reset and power-down on remove() and failed probe()
>   ASoC: cs42l42: free_irq() before powering-down on probe() fail
> 
> [...]

Applied to

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

Thanks!

[1/2] ASoC: cs42l42: Reset and power-down on remove() and failed probe()
      commit: 6cb725b8a5cc7b9106d5d6dd5d2ca78c76913775
[2/2] ASoC: cs42l42: free_irq() before powering-down on probe() fail
      commit: a10148a8cf561d728c0f57994330b2da1df35577

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