mfd: ab8500_gpadc: Raw ADC value converted twice

A bug made the raw ADC value converted to voltage entity
twice. Renamed some gpadc function arguments to clarify
use.

ST-Ericsson ID: 344073
ST-Ericsson Linux next: Tested by ELINWAL
ST-Ericsson FOSS-OUT ID: Trivial

Change-Id: I53465c2e65c001c23d13929b4bdb59700eb7cf18
Signed-off-by: Kalle Komierowski <kalle.komierowski@gmail.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/24552
Tested-by: Karl KOMIEROWSKI <karl.komierowski@stericsson.com>
Reviewed-by: Mattias WALLIN <mattias.wallin@stericsson.com>
Reviewed-by: John BECKETT <john.beckett@stericsson.com>
Reviewed-by: QATEST

2 files changed, 30 insertions, 22 deletions

diff --git a/drivers/mfd/ab8500-gpadc.c b/drivers/mfd/ab8500-gpadc.c
index 82124a51ba9..38fbb7025a8 100644
--- a/drivers/mfd/ab8500-gpadc.c
+++ b/drivers/mfd/ab8500-gpadc.c
@@ -142,12 +142,12 @@ EXPORT_SYMBOL(ab8500_gpadc_get);
 /**
  * ab8500_gpadc_ad_to_voltage() - Convert a raw ADC value to a voltage
  */
-int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc, u8 input,
+int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc, u8 channel,
 	int ad_value)
 {
 	int res;
 
-	switch (input) {
+	switch (channel) {
 	case MAIN_CHARGER_V:
 		/* For some reason we don't have calibrated data */
 		if (!gpadc->cal_data[ADC_INPUT_VMAIN].gain) {
@@ -234,32 +234,41 @@ int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc, u8 input,
 
 /**
  * ab8500_gpadc_convert() - gpadc conversion
- * @input:	analog input to be converted to digital data
+ * @channel:	analog channel to be converted to digital data
  *
  * This function converts the selected analog i/p to digital
  * data.
  */
-int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 input)
+int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 channel)
 {
-	int data;
-	int ret;
+	int ad_value;
+	int voltage;
 
-	data = ab8500_gpadc_read_raw(gpadc, input);
-	ret = ab8500_gpadc_ad_to_voltage(gpadc, input, data);
-	return ret;
+	ad_value = ab8500_gpadc_read_raw(gpadc, channel);
+	if (ad_value < 0) {
+		dev_err(gpadc->dev, "GPADC raw value failed ch: %d\n", channel);
+		return ad_value;
+	}
+
+	voltage = ab8500_gpadc_ad_to_voltage(gpadc, channel, ad_value);
+
+	if (voltage < 0)
+		dev_err(gpadc->dev, "GPADC to voltage conversion failed ch:"
+			" %d AD: 0x%x\n", channel, ad_value);
+
+	return voltage;
 }
 
 /**
  * ab8500_gpadc_read_raw() - gpadc read
- * @input:	analog input to be read
+ * @channel:	analog channel to be read
  *
  * This function obtains the raw ADC value, this then needs
  * to be converted by calling ab8500_gpadc_ad_to_voltage()
  */
-int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 input)
+int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 channel)
 {
 	int ret;
-	u16 data = 0;
 	int looplimit = 0;
 	u8 val, low_data, high_data;
 
@@ -294,9 +303,9 @@ int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 input)
 		goto out;
 	}
 
-	/* Select the input source and set average samples to 16 */
+	/* Select the channel source and set average samples to 16 */
 	ret = abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC,
-		AB8500_GPADC_CTRL2_REG, (input | SW_AVG_16));
+		AB8500_GPADC_CTRL2_REG, (channel | SW_AVG_16));
 	if (ret < 0) {
 		dev_err(gpadc->dev,
 			"gpadc_conversion: set avg samples failed\n");
@@ -308,7 +317,7 @@ int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 input)
 	 * charging current sense if it needed, ABB 3.0 needs some special
 	 * treatment too.
 	 */
-	switch (input) {
+	switch (channel) {
 	case MAIN_CHARGER_C:
 	case USB_CHARGER_C:
 		ret = abx500_mask_and_set_register_interruptible(gpadc->dev,
@@ -375,7 +384,6 @@ int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 input)
 		goto out;
 	}
 
-	data = (high_data << 8) | low_data;
 	/* Disable GPADC */
 	ret = abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC,
 		AB8500_GPADC_CTRL1_REG, DIS_GPADC);
@@ -386,8 +394,8 @@ int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 input)
 	/* Disable VTVout LDO this is required for GPADC */
 	regulator_disable(gpadc->regu);
 	mutex_unlock(&gpadc->ab8500_gpadc_lock);
-	ret = ab8500_gpadc_ad_to_voltage(gpadc, input, data);
-	return ret;
+
+	return (high_data << 8) | low_data;
 
 out:
 	/*
@@ -401,7 +409,7 @@ out:
 	regulator_disable(gpadc->regu);
 	mutex_unlock(&gpadc->ab8500_gpadc_lock);
 	dev_err(gpadc->dev,
-		"gpadc_conversion: Failed to AD convert channel %d\n", input);
+		"gpadc_conversion: Failed to AD convert channel %d\n", channel);
 	return ret;
 }
 
diff --git a/include/linux/mfd/ab8500/gpadc.h b/include/linux/mfd/ab8500/gpadc.h
index 6688cbc8208..fa706c5a04a 100644
--- a/include/linux/mfd/ab8500/gpadc.h
+++ b/include/linux/mfd/ab8500/gpadc.h
@@ -27,9 +27,9 @@
 struct ab8500_gpadc;
 
 struct ab8500_gpadc *ab8500_gpadc_get(void);
-int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 input);
-int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 input);
+int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 channel);
+int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 channel);
 int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc,
-				u8 input, int ad_value);
+    u8 channel, int ad_value);
 
 #endif /* _AB8500_GPADC_H */