iio:pressure:bmp280: cleanup

PATCH In review Hartmut Knaack 3 participants 3 messages Dec 19, 2014 – Dec 26, 2014 IIO

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Hartmut Knaack

author

2014-12-19 22:59 UTC #0 lore raw

PATCH v2 1/1 iio:pressure:bmp280: cleanup

The calculations for temperature and pressure compensation were already slightly optimized in comparison to the datasheet. So, it makes sense to optimize even a bit more, making proper use of C operators:
- variable t in bmp280_compensate_temp() can be eliminated by directly returning the result of the relevant equation.
- make use of the += operator and eliminate an unnecessary parenthesis level in

    bmp280_compensate_press().

When the initialization of the ctrl_meas register fails, the error message will now mention the right register name.
During probe, i2c_set_clientdata() is called, although it is not necessary. Drop it.

Signed-off-by Hartmut Knaack <[email protected]>

---
Changes in V2:
Rebase after refactoring of compensation code.

drivers/iio/pressure/bmp280.c +6 ~~-10~~

index 47dfd34..7c623e2 100644
@@ -148,7 +148,7 @@ static s32 bmp280_compensate_temp(struct bmp280_data *data,
 				  s32 adc_temp)
 {
 	int ret;
-	s32 var1, var2, t;
+	s32 var1, var2;
 	__le16 buf[BMP280_COMP_TEMP_REG_COUNT / 2];
 
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,

@@ -173,10 +173,7 @@ static s32 bmp280_compensate_temp(struct bmp280_data *data,
 		  ((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1])))) >> 12) *
 		((s32)(s16)le16_to_cpu(buf[T3]))) >> 14;
 
-	data->t_fine = var1 + var2;
-	t = (data->t_fine * 5 + 128) >> 8;
-
-	return t;
+	return (data->t_fine * 5 + 128) >> 8;
 }
 
 /*

@@ -203,8 +200,8 @@ static u32 bmp280_compensate_press(struct bmp280_data *data,
 
 	var1 = ((s64)data->t_fine) - 128000;
 	var2 = var1 * var1 * (s64)(s16)le16_to_cpu(buf[P6]);
-	var2 = var2 + ((var1 * (s64)(s16)le16_to_cpu(buf[P5])) << 17);
-	var2 = var2 + (((s64)(s16)le16_to_cpu(buf[P4])) << 35);
+	var2 += (var1 * (s64)(s16)le16_to_cpu(buf[P5])) << 17;
+	var2 += ((s64)(s16)le16_to_cpu(buf[P4])) << 35;
 	var1 = ((var1 * var1 * (s64)(s16)le16_to_cpu(buf[P3])) >> 8) +
 		((var1 * (s64)(s16)le16_to_cpu(buf[P2])) << 12);
 	var1 = ((((s64)1) << 47) + var1) * ((s64)le16_to_cpu(buf[P1])) >> 33;

@@ -218,7 +215,7 @@ static u32 bmp280_compensate_press(struct bmp280_data *data,
 	var2 = (((s64)(s16)le16_to_cpu(buf[P8])) * p) >> 19;
 	p = ((p + var1 + var2) >> 8) + (((s64)(s16)le16_to_cpu(buf[P7])) << 4);
 
-	return (u32) p;
+	return (u32)p;
 }
 
 static int bmp280_read_temp(struct bmp280_data *data,

@@ -330,7 +327,7 @@ static int bmp280_chip_init(struct bmp280_data *data)
 				 BMP280_MODE_NORMAL);
 	if (ret < 0) {
 		dev_err(&data->client->dev,
-			"failed to write config register\n");
+			"failed to write ctrl_meas register\n");
 		return ret;
 	}

@@ -358,7 +355,6 @@ static int bmp280_probe(struct i2c_client *client,
 	if (!indio_dev)
 		return -ENOMEM;
 
-	i2c_set_clientdata(client, indio_dev);
 	data = iio_priv(indio_dev);
 	mutex_init(&data->lock);
 	data->client = client;

Vlad Dogaru

Reviewed-by on v2 1/1

2014-12-22 12:28 UTC #1 lore raw

Quoted 6 lines · Hartmut Knaack

The calculations for temperature and pressure compensation were already slightly optimized in comparison to the datasheet. So, it makes sense to optimize even a bit more, making proper use of C operators:
- variable t in bmp280_compensate_temp() can be eliminated by directly returning the result of the relevant equation.
- make use of the += operator and eliminate an unnecessary parenthesis level in

Quoted 7 lines

    bmp280_compensate_press().
When the initialization of the ctrl_meas register fails, the error message will now mention the right register name.
During probe, i2c_set_clientdata() is called, although it is not necessary. Drop it.
Signed-off-by Hartmut Knaack <[email protected]>

Reviewed-by Vlad Dogaru <[email protected]>

Thanks for following up with this one, Hartmut.

Quoted 66 lines

---
Changes in V2:
Rebase after refactoring of compensation code.

drivers/iio/pressure/bmp280.c +6 ~~-10~~

index 47dfd34..7c623e2 100644
@@ -148,7 +148,7 @@ static s32 bmp280_compensate_temp(struct bmp280_data *data,
 				  s32 adc_temp)
 {
 	int ret;
-	s32 var1, var2, t;
+	s32 var1, var2;
 	__le16 buf[BMP280_COMP_TEMP_REG_COUNT / 2];
 
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,

@@ -173,10 +173,7 @@ static s32 bmp280_compensate_temp(struct bmp280_data *data,
 		  ((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1])))) >> 12) *
 		((s32)(s16)le16_to_cpu(buf[T3]))) >> 14;
 
-	data->t_fine = var1 + var2;
-	t = (data->t_fine * 5 + 128) >> 8;
-
-	return t;
+	return (data->t_fine * 5 + 128) >> 8;
 }
 
 /*

@@ -203,8 +200,8 @@ static u32 bmp280_compensate_press(struct bmp280_data *data,
 
 	var1 = ((s64)data->t_fine) - 128000;
 	var2 = var1 * var1 * (s64)(s16)le16_to_cpu(buf[P6]);
-	var2 = var2 + ((var1 * (s64)(s16)le16_to_cpu(buf[P5])) << 17);
-	var2 = var2 + (((s64)(s16)le16_to_cpu(buf[P4])) << 35);
+	var2 += (var1 * (s64)(s16)le16_to_cpu(buf[P5])) << 17;
+	var2 += ((s64)(s16)le16_to_cpu(buf[P4])) << 35;
 	var1 = ((var1 * var1 * (s64)(s16)le16_to_cpu(buf[P3])) >> 8) +
 		((var1 * (s64)(s16)le16_to_cpu(buf[P2])) << 12);
 	var1 = ((((s64)1) << 47) + var1) * ((s64)le16_to_cpu(buf[P1])) >> 33;

@@ -218,7 +215,7 @@ static u32 bmp280_compensate_press(struct bmp280_data *data,
 	var2 = (((s64)(s16)le16_to_cpu(buf[P8])) * p) >> 19;
 	p = ((p + var1 + var2) >> 8) + (((s64)(s16)le16_to_cpu(buf[P7])) << 4);
 
-	return (u32) p;
+	return (u32)p;
 }
 
 static int bmp280_read_temp(struct bmp280_data *data,

@@ -330,7 +327,7 @@ static int bmp280_chip_init(struct bmp280_data *data)
 				 BMP280_MODE_NORMAL);
 	if (ret < 0) {
 		dev_err(&data->client->dev,
-			"failed to write config register\n");
+			"failed to write ctrl_meas register\n");
 		return ret;
 	}

@@ -358,7 +355,6 @@ static int bmp280_probe(struct i2c_client *client,
 	if (!indio_dev)
 		return -ENOMEM;
 
-	i2c_set_clientdata(client, indio_dev);
 	data = iio_priv(indio_dev);
 	mutex_init(&data->lock);
 	data->client = client;

Jonathan Cameron

maintainer

2014-12-26 10:33 UTC #2 lore raw

Quoted 13 lines · Vlad Dogaru

Quoted 12 lines · Hartmut Knaack
The calculations for temperature and pressure compensation were already slightly optimized in comparison to the datasheet. So, it makes sense to optimize even a bit more, making proper use of C operators:
- variable t in bmp280_compensate_temp() can be eliminated by directly returning the result of the relevant equation.
- make use of the += operator and eliminate an unnecessary parenthesis level in
    bmp280_compensate_press().
When the initialization of the ctrl_meas register fails, the error message will now mention the right register name.
During probe, i2c_set_clientdata() is called, although it is not necessary. Drop it.

Quoted 4 lines

Quoted 1 line
Signed-off-by Hartmut Knaack <[email protected]>
Reviewed-by Vlad Dogaru <[email protected]>
Thanks for following up with this one, Hartmut.

Applied to the togreg branch of iio.git -- initially pushed out as testing for the autobuilders to play with it. Well, it will be once I've caught up with some more reviews..

Jonathan

Quoted 72 lines

Quoted 60 lines

---
Changes in V2:
Rebase after refactoring of compensation code.

drivers/iio/pressure/bmp280.c +6 -9

index 47dfd34..7c623e2 100644
@@ -148,7 +148,7 @@ static s32 bmp280_compensate_temp(struct bmp280_data *data,
 				  s32 adc_temp)
 {
 	int ret;
-	s32 var1, var2, t;
+	s32 var1, var2;
 	__le16 buf[BMP280_COMP_TEMP_REG_COUNT / 2];
 
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,

@@ -173,10 +173,7 @@ static s32 bmp280_compensate_temp(struct bmp280_data *data,
 		  ((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1])))) >> 12) *
 		((s32)(s16)le16_to_cpu(buf[T3]))) >> 14;
 
-	data->t_fine = var1 + var2;
-	t = (data->t_fine * 5 + 128) >> 8;
-
-	return t;
+	return (data->t_fine * 5 + 128) >> 8;
 }
 
 /*

@@ -203,8 +200,8 @@ static u32 bmp280_compensate_press(struct bmp280_data *data,
 
 	var1 = ((s64)data->t_fine) - 128000;
 	var2 = var1 * var1 * (s64)(s16)le16_to_cpu(buf[P6]);
-	var2 = var2 + ((var1 * (s64)(s16)le16_to_cpu(buf[P5])) << 17);
-	var2 = var2 + (((s64)(s16)le16_to_cpu(buf[P4])) << 35);
+	var2 += (var1 * (s64)(s16)le16_to_cpu(buf[P5])) << 17;
+	var2 += ((s64)(s16)le16_to_cpu(buf[P4])) << 35;
 	var1 = ((var1 * var1 * (s64)(s16)le16_to_cpu(buf[P3])) >> 8) +
 		((var1 * (s64)(s16)le16_to_cpu(buf[P2])) << 12);
 	var1 = ((((s64)1) << 47) + var1) * ((s64)le16_to_cpu(buf[P1])) >> 33;

@@ -218,7 +215,7 @@ static u32 bmp280_compensate_press(struct bmp280_data *data,
 	var2 = (((s64)(s16)le16_to_cpu(buf[P8])) * p) >> 19;
 	p = ((p + var1 + var2) >> 8) + (((s64)(s16)le16_to_cpu(buf[P7])) << 4);
 
-	return (u32) p;
+	return (u32)p;
 }
 
 static int bmp280_read_temp(struct bmp280_data *data,

@@ -330,7 +327,7 @@ static int bmp280_chip_init(struct bmp280_data *data)
 				 BMP280_MODE_NORMAL);
 	if (ret < 0) {
 		dev_err(&data->client->dev,
-			"failed to write config register\n");
+			"failed to write ctrl_meas register\n");
 		return ret;
 	}

drivers/iio/pressure/bmp280.c static int bmp280_probe(struct i2c_client *client, · line 360

Quoted 7 lines

drivers/iio/pressure/bmp280.c +0 -1

@@ -358,7 +355,6 @@ static int bmp280_probe(struct i2c_client *client,
 	if (!indio_dev)
 		return -ENOMEM;
 
-	i2c_set_clientdata(client, indio_dev);
 	data = iio_priv(indio_dev);
 	mutex_init(&data->lock);
 	data->client = client;

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