All of lore.kernel.org
 help / color / mirror / Atom feed
From: Mike Willard <mwillard@izotope.com>
To: mwillard@izotope.com
Cc: Brian Austin <brian.austin@cirrus.com>,
	Paul Handrigan <Paul.Handrigan@cirrus.com>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>, Jaroslav Kysela <perex@perex.cz>,
	Takashi Iwai <tiwai@suse.com>,
	alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org
Subject: [PATCH] ASoC: cs4270: pull reset GPIO low then high
Date: Wed,  1 Apr 2020 20:54:54 +0000	[thread overview]
Message-ID: <20200401205454.79792-1-mwillard@izotope.com> (raw)

Pull the RST line low then high when initializing the driver,
in order to force a reset of the chip.
Previously, the line was not pulled low, which could result in
the chip registers not resetting to their default values on boot.

Signed-off-by: Mike Willard <mwillard@izotope.com>
---
 sound/soc/codecs/cs4270.c | 40 ++++++++++++++++++++++++++++++++++-----
 1 file changed, 35 insertions(+), 5 deletions(-)

diff --git a/sound/soc/codecs/cs4270.c b/sound/soc/codecs/cs4270.c
index 5f25b9f872bd..8a02791e44ad 100644
--- a/sound/soc/codecs/cs4270.c
+++ b/sound/soc/codecs/cs4270.c
@@ -137,6 +137,9 @@ struct cs4270_private {
 
 	/* power domain regulators */
 	struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
+
+	/* reset gpio */
+	struct gpio_desc *reset_gpio;
 };
 
 static const struct snd_soc_dapm_widget cs4270_dapm_widgets[] = {
@@ -648,6 +651,22 @@ static const struct regmap_config cs4270_regmap = {
 	.volatile_reg =		cs4270_reg_is_volatile,
 };
 
+/**
+ * cs4270_i2c_remove - deinitialize the I2C interface of the CS4270
+ * @i2c_client: the I2C client object
+ *
+ * This function puts the chip into low power mode when the i2c device
+ * is removed.
+ */
+static int cs4270_i2c_remove(struct i2c_client *i2c_client)
+{
+	struct cs4270_private *cs4270 = i2c_get_clientdata(i2c_client);
+
+	gpiod_set_value_cansleep(cs4270->reset_gpio, 0);
+
+	return 0;
+}
+
 /**
  * cs4270_i2c_probe - initialize the I2C interface of the CS4270
  * @i2c_client: the I2C client object
@@ -660,7 +679,6 @@ static int cs4270_i2c_probe(struct i2c_client *i2c_client,
 	const struct i2c_device_id *id)
 {
 	struct cs4270_private *cs4270;
-	struct gpio_desc *reset_gpiod;
 	unsigned int val;
 	int ret, i;
 
@@ -679,10 +697,21 @@ static int cs4270_i2c_probe(struct i2c_client *i2c_client,
 	if (ret < 0)
 		return ret;
 
-	reset_gpiod = devm_gpiod_get_optional(&i2c_client->dev, "reset",
-					      GPIOD_OUT_HIGH);
-	if (PTR_ERR(reset_gpiod) == -EPROBE_DEFER)
-		return -EPROBE_DEFER;
+	/* reset the device */
+	cs4270->reset_gpio = devm_gpiod_get_optional(&i2c_client->dev, "reset",
+						     GPIOD_OUT_LOW);
+	if (IS_ERR(cs4270->reset_gpio)) {
+		dev_dbg(&i2c_client->dev, "Error getting CS4270 reset GPIO\n");
+		return PTR_ERR(cs4270->reset_gpio);
+	}
+
+	if (cs4270->reset_gpio) {
+		dev_dbg(&i2c_client->dev, "Found reset GPIO\n");
+		gpiod_set_value_cansleep(cs4270->reset_gpio, 1);
+	}
+
+	/* Sleep 500ns before i2c communications */
+	ndelay(500);
 
 	cs4270->regmap = devm_regmap_init_i2c(i2c_client, &cs4270_regmap);
 	if (IS_ERR(cs4270->regmap))
@@ -735,6 +764,7 @@ static struct i2c_driver cs4270_i2c_driver = {
 	},
 	.id_table = cs4270_id,
 	.probe = cs4270_i2c_probe,
+	.remove = cs4270_i2c_remove,
 };
 
 module_i2c_driver(cs4270_i2c_driver);
-- 
2.17.1


WARNING: multiple messages have this Message-ID (diff)
From: Mike Willard <mwillard@izotope.com>
To: mwillard@izotope.com
Cc: Brian Austin <brian.austin@cirrus.com>,
	alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org,
	Takashi Iwai <tiwai@suse.com>,
	Paul Handrigan <Paul.Handrigan@cirrus.com>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>
Subject: [PATCH] ASoC: cs4270: pull reset GPIO low then high
Date: Wed,  1 Apr 2020 20:54:54 +0000	[thread overview]
Message-ID: <20200401205454.79792-1-mwillard@izotope.com> (raw)

Pull the RST line low then high when initializing the driver,
in order to force a reset of the chip.
Previously, the line was not pulled low, which could result in
the chip registers not resetting to their default values on boot.

Signed-off-by: Mike Willard <mwillard@izotope.com>
---
 sound/soc/codecs/cs4270.c | 40 ++++++++++++++++++++++++++++++++++-----
 1 file changed, 35 insertions(+), 5 deletions(-)

diff --git a/sound/soc/codecs/cs4270.c b/sound/soc/codecs/cs4270.c
index 5f25b9f872bd..8a02791e44ad 100644
--- a/sound/soc/codecs/cs4270.c
+++ b/sound/soc/codecs/cs4270.c
@@ -137,6 +137,9 @@ struct cs4270_private {
 
 	/* power domain regulators */
 	struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
+
+	/* reset gpio */
+	struct gpio_desc *reset_gpio;
 };
 
 static const struct snd_soc_dapm_widget cs4270_dapm_widgets[] = {
@@ -648,6 +651,22 @@ static const struct regmap_config cs4270_regmap = {
 	.volatile_reg =		cs4270_reg_is_volatile,
 };
 
+/**
+ * cs4270_i2c_remove - deinitialize the I2C interface of the CS4270
+ * @i2c_client: the I2C client object
+ *
+ * This function puts the chip into low power mode when the i2c device
+ * is removed.
+ */
+static int cs4270_i2c_remove(struct i2c_client *i2c_client)
+{
+	struct cs4270_private *cs4270 = i2c_get_clientdata(i2c_client);
+
+	gpiod_set_value_cansleep(cs4270->reset_gpio, 0);
+
+	return 0;
+}
+
 /**
  * cs4270_i2c_probe - initialize the I2C interface of the CS4270
  * @i2c_client: the I2C client object
@@ -660,7 +679,6 @@ static int cs4270_i2c_probe(struct i2c_client *i2c_client,
 	const struct i2c_device_id *id)
 {
 	struct cs4270_private *cs4270;
-	struct gpio_desc *reset_gpiod;
 	unsigned int val;
 	int ret, i;
 
@@ -679,10 +697,21 @@ static int cs4270_i2c_probe(struct i2c_client *i2c_client,
 	if (ret < 0)
 		return ret;
 
-	reset_gpiod = devm_gpiod_get_optional(&i2c_client->dev, "reset",
-					      GPIOD_OUT_HIGH);
-	if (PTR_ERR(reset_gpiod) == -EPROBE_DEFER)
-		return -EPROBE_DEFER;
+	/* reset the device */
+	cs4270->reset_gpio = devm_gpiod_get_optional(&i2c_client->dev, "reset",
+						     GPIOD_OUT_LOW);
+	if (IS_ERR(cs4270->reset_gpio)) {
+		dev_dbg(&i2c_client->dev, "Error getting CS4270 reset GPIO\n");
+		return PTR_ERR(cs4270->reset_gpio);
+	}
+
+	if (cs4270->reset_gpio) {
+		dev_dbg(&i2c_client->dev, "Found reset GPIO\n");
+		gpiod_set_value_cansleep(cs4270->reset_gpio, 1);
+	}
+
+	/* Sleep 500ns before i2c communications */
+	ndelay(500);
 
 	cs4270->regmap = devm_regmap_init_i2c(i2c_client, &cs4270_regmap);
 	if (IS_ERR(cs4270->regmap))
@@ -735,6 +764,7 @@ static struct i2c_driver cs4270_i2c_driver = {
 	},
 	.id_table = cs4270_id,
 	.probe = cs4270_i2c_probe,
+	.remove = cs4270_i2c_remove,
 };
 
 module_i2c_driver(cs4270_i2c_driver);
-- 
2.17.1


             reply	other threads:[~2020-04-01 20:55 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-01 20:54 Mike Willard [this message]
2020-04-01 20:54 ` [PATCH] ASoC: cs4270: pull reset GPIO low then high Mike Willard
2020-04-07 14:30 ` Applied "ASoC: cs4270: pull reset GPIO low then high" to the asoc tree Mark Brown
2020-04-07 14:30   ` Mark Brown

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200401205454.79792-1-mwillard@izotope.com \
    --to=mwillard@izotope.com \
    --cc=Paul.Handrigan@cirrus.com \
    --cc=alsa-devel@alsa-project.org \
    --cc=brian.austin@cirrus.com \
    --cc=broonie@kernel.org \
    --cc=lgirdwood@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=perex@perex.cz \
    --cc=tiwai@suse.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.