mfd: Refactor ab8500 GPADC API, add raw access

Refactor the GPADC interface to avoid bugs in calling code:

- ab8500_gpadc_[convert|read_raw|ad_to_voltage] clarifies
  each functions use case, *convert wraps *read_raw, and we
  can access raw ADC values properly.
- Renamed gpadc function arguments from "input" to "channel" to
  clarify use, so we don't get confused again.

Signed-off-by: Kalle Komierowski <kalle.komierowski@stericsson.com>
Reviewed-by: Mattias Wallin <mattias.wallin@stericsson.com>
Reviewed-by: John Beckett <john.beckett@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This commit is contained in:
Karl Komierowski 2011-08-10 15:09:43 +02:00 committed by Samuel Ortiz
parent 981c65a9b3
commit bd4a40b57b
2 changed files with 47 additions and 14 deletions

View File

@ -143,12 +143,15 @@ struct ab8500_gpadc *ab8500_gpadc_get(char *name)
}
EXPORT_SYMBOL(ab8500_gpadc_get);
static int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc, u8 input,
/**
* ab8500_gpadc_ad_to_voltage() - Convert a raw ADC value to a voltage
*/
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) {
@ -232,18 +235,46 @@ static int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc, u8 input,
}
return res;
}
EXPORT_SYMBOL(ab8500_gpadc_ad_to_voltage);
/**
* 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 ad_value;
int voltage;
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;
}
EXPORT_SYMBOL(ab8500_gpadc_convert);
/**
* ab8500_gpadc_read_raw() - gpadc 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 channel)
{
int ret;
u16 data = 0;
int looplimit = 0;
u8 val, low_data, high_data;
@ -278,9 +309,9 @@ int ab8500_gpadc_convert(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");
@ -292,7 +323,7 @@ int ab8500_gpadc_convert(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,
@ -359,7 +390,6 @@ int ab8500_gpadc_convert(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);
@ -370,8 +400,8 @@ int ab8500_gpadc_convert(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:
/*
@ -385,10 +415,10 @@ int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 input)
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;
}
EXPORT_SYMBOL(ab8500_gpadc_convert);
EXPORT_SYMBOL(ab8500_gpadc_read_raw);
/**
* ab8500_bm_gpswadcconvend_handler() - isr for s/w gpadc conversion completion

View File

@ -27,6 +27,9 @@
struct ab8500_gpadc;
struct ab8500_gpadc *ab8500_gpadc_get(char *name);
int ab8500_gpadc_convert(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 channel, int ad_value);
#endif /* _AB8500_GPADC_H */