diff mbox

[v2,1/3] mfd: tps6586x: add version detection

Message ID 2d5282f031a16d2ff227694daaabc977440fbd2e.1385913228.git.stefan@agner.ch (mailing list archive)
State New, archived
Headers show

Commit Message

Stefan Agner Dec. 1, 2013, 3:59 p.m. UTC
Use the VERSIONCRC to determine the exact device version. According to
the datasheet this register can be used as device identifier. The
identification is needed since some tps6586x regulators use a different
voltage table.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 drivers/mfd/tps6586x.c       | 47 +++++++++++++++++++++++++++++++++++++-------
 include/linux/mfd/tps6586x.h |  7 +++++++
 2 files changed, 47 insertions(+), 7 deletions(-)

Comments

Thierry Reding Dec. 2, 2013, 9:17 a.m. UTC | #1
On Sun, Dec 01, 2013 at 04:59:13PM +0100, Stefan Agner wrote:
> Use the VERSIONCRC to determine the exact device version. According to
> the datasheet this register can be used as device identifier. The
> identification is needed since some tps6586x regulators use a different
> voltage table.
> 
> Signed-off-by: Stefan Agner <stefan@agner.ch>
> ---
>  drivers/mfd/tps6586x.c       | 47 +++++++++++++++++++++++++++++++++++++-------
>  include/linux/mfd/tps6586x.h |  7 +++++++
>  2 files changed, 47 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/mfd/tps6586x.c b/drivers/mfd/tps6586x.c
> index ee61fd7..8fc5a68 100644
> --- a/drivers/mfd/tps6586x.c
> +++ b/drivers/mfd/tps6586x.c
> @@ -124,6 +124,7 @@ struct tps6586x {
>  	struct device		*dev;
>  	struct i2c_client	*client;
>  	struct regmap		*regmap;
> +	int			version;
>  
>  	int			irq;
>  	struct irq_chip		irq_chip;
> @@ -208,6 +209,14 @@ int tps6586x_irq_get_virq(struct device *dev, int irq)
>  }
>  EXPORT_SYMBOL_GPL(tps6586x_irq_get_virq);
>  
> +int tps6586x_get_version(struct device *dev)
> +{
> +	struct tps6586x *tps6586x = dev_get_drvdata(dev);
> +
> +	return tps6586x->version;
> +}
> +EXPORT_SYMBOL_GPL(tps6586x_get_version);
> +
>  static int __remove_subdev(struct device *dev, void *unused)
>  {
>  	platform_device_unregister(to_platform_device(dev));
> @@ -472,6 +481,31 @@ static void tps6586x_power_off(void)
>  	tps6586x_set_bits(tps6586x_dev, TPS6586X_SUPPLYENE, SLEEP_MODE_BIT);
>  }
>  
> +static void tps6586x_print_version(struct i2c_client *client, int version)
> +{
> +	const char *name;
> +
> +	switch (version) {
> +	case TPS658621A:
> +		name = "TPS658621A";
> +		break;
> +	case TPS658621CD:
> +		name = "TPS658621C/D";
> +		break;
> +	case TPS658623:
> +		name = "TPS658623";
> +		break;
> +	case TPS658643:
> +		name = "TPS658643";
> +		break;
> +	default:
> +		name = "TPS6586X";
> +		break;
> +	}
> +
> +	dev_info(&client->dev, "Found %s, VERSIONCRC is %02x\n", name, version);
> +}
> +
>  static int tps6586x_i2c_probe(struct i2c_client *client,
>  					const struct i2c_device_id *id)
>  {
> @@ -487,19 +521,18 @@ static int tps6586x_i2c_probe(struct i2c_client *client,
>  		return -ENOTSUPP;
>  	}
>  
> +	tps6586x = devm_kzalloc(&client->dev, sizeof(*tps6586x), GFP_KERNEL);
> +	if (!tps6586x)
> +		return -ENOMEM;
> +

This hunk is being needlessly moved around....

>  	ret = i2c_smbus_read_byte_data(client, TPS6586X_VERSIONCRC);
>  	if (ret < 0) {
>  		dev_err(&client->dev, "Chip ID read failed: %d\n", ret);
>  		return -EIO;
>  	}
>  
> -	dev_info(&client->dev, "VERSIONCRC is %02x\n", ret);
> -
> -	tps6586x = devm_kzalloc(&client->dev, sizeof(*tps6586x), GFP_KERNEL);
> -	if (tps6586x == NULL) {
> -		dev_err(&client->dev, "memory for tps6586x alloc failed\n");
> -		return -ENOMEM;
> -	}
> +	tps6586x->version = ret;
> +	tps6586x_print_version(client, tps6586x->version);

... none of this new code overwrites "ret", so you could just keep the
previous order of operations. It probably doesn't matter all that much,
but deferring allocation until we're sure that the chip actually exists
is a minor optimization. Also not moving that hunk around makes the
patch simpler.

Thierry
Mark Brown Dec. 2, 2013, 12:21 p.m. UTC | #2
On Sun, Dec 01, 2013 at 04:59:13PM +0100, Stefan Agner wrote:

> +int tps6586x_get_version(struct device *dev)
> +{
> +	struct tps6586x *tps6586x = dev_get_drvdata(dev);
> +
> +	return tps6586x->version;
> +}
> +EXPORT_SYMBOL_GPL(tps6586x_get_version);

May as well make this a static inline in the header.
diff mbox

Patch

diff --git a/drivers/mfd/tps6586x.c b/drivers/mfd/tps6586x.c
index ee61fd7..8fc5a68 100644
--- a/drivers/mfd/tps6586x.c
+++ b/drivers/mfd/tps6586x.c
@@ -124,6 +124,7 @@  struct tps6586x {
 	struct device		*dev;
 	struct i2c_client	*client;
 	struct regmap		*regmap;
+	int			version;
 
 	int			irq;
 	struct irq_chip		irq_chip;
@@ -208,6 +209,14 @@  int tps6586x_irq_get_virq(struct device *dev, int irq)
 }
 EXPORT_SYMBOL_GPL(tps6586x_irq_get_virq);
 
+int tps6586x_get_version(struct device *dev)
+{
+	struct tps6586x *tps6586x = dev_get_drvdata(dev);
+
+	return tps6586x->version;
+}
+EXPORT_SYMBOL_GPL(tps6586x_get_version);
+
 static int __remove_subdev(struct device *dev, void *unused)
 {
 	platform_device_unregister(to_platform_device(dev));
@@ -472,6 +481,31 @@  static void tps6586x_power_off(void)
 	tps6586x_set_bits(tps6586x_dev, TPS6586X_SUPPLYENE, SLEEP_MODE_BIT);
 }
 
+static void tps6586x_print_version(struct i2c_client *client, int version)
+{
+	const char *name;
+
+	switch (version) {
+	case TPS658621A:
+		name = "TPS658621A";
+		break;
+	case TPS658621CD:
+		name = "TPS658621C/D";
+		break;
+	case TPS658623:
+		name = "TPS658623";
+		break;
+	case TPS658643:
+		name = "TPS658643";
+		break;
+	default:
+		name = "TPS6586X";
+		break;
+	}
+
+	dev_info(&client->dev, "Found %s, VERSIONCRC is %02x\n", name, version);
+}
+
 static int tps6586x_i2c_probe(struct i2c_client *client,
 					const struct i2c_device_id *id)
 {
@@ -487,19 +521,18 @@  static int tps6586x_i2c_probe(struct i2c_client *client,
 		return -ENOTSUPP;
 	}
 
+	tps6586x = devm_kzalloc(&client->dev, sizeof(*tps6586x), GFP_KERNEL);
+	if (!tps6586x)
+		return -ENOMEM;
+
 	ret = i2c_smbus_read_byte_data(client, TPS6586X_VERSIONCRC);
 	if (ret < 0) {
 		dev_err(&client->dev, "Chip ID read failed: %d\n", ret);
 		return -EIO;
 	}
 
-	dev_info(&client->dev, "VERSIONCRC is %02x\n", ret);
-
-	tps6586x = devm_kzalloc(&client->dev, sizeof(*tps6586x), GFP_KERNEL);
-	if (tps6586x == NULL) {
-		dev_err(&client->dev, "memory for tps6586x alloc failed\n");
-		return -ENOMEM;
-	}
+	tps6586x->version = ret;
+	tps6586x_print_version(client, tps6586x->version);
 
 	tps6586x->client = client;
 	tps6586x->dev = &client->dev;
diff --git a/include/linux/mfd/tps6586x.h b/include/linux/mfd/tps6586x.h
index 8799454..cbecec2 100644
--- a/include/linux/mfd/tps6586x.h
+++ b/include/linux/mfd/tps6586x.h
@@ -13,6 +13,12 @@ 
 #define TPS6586X_SLEW_RATE_SET		0x08
 #define TPS6586X_SLEW_RATE_MASK         0x07
 
+/* VERSION CRC */
+#define TPS658621A	0x15
+#define TPS658621CD	0x2c
+#define TPS658623	0x1b
+#define TPS658643	0x03
+
 enum {
 	TPS6586X_ID_SYS,
 	TPS6586X_ID_SM_0,
@@ -97,5 +103,6 @@  extern int tps6586x_clr_bits(struct device *dev, int reg, uint8_t bit_mask);
 extern int tps6586x_update(struct device *dev, int reg, uint8_t val,
 			   uint8_t mask);
 extern int tps6586x_irq_get_virq(struct device *dev, int irq);
+extern int tps6586x_get_version(struct device *dev);
 
 #endif /*__LINUX_MFD_TPS6586X_H */