From 0a74f34f0460f306915e11df7a59089a6c460348 Mon Sep 17 00:00:00 2001 From: Sanchayan Maity Date: Fri, 19 Sep 2014 18:28:42 +0530 Subject: drivers/iio/adc/vf610-adc: Add temperature sensor support Vybrid ADC peripheral includes a temperature sensor which is connected to channel number 26. This patch adds support for the sensor. The raw value is read and the temperature calculated in milli degree Celsius, which is returned using IIO_CHAN_INFO_PROCESSED option. Signed-off-by: Sanchayan Maity Signed-off-by: Stefan Agner --- drivers/iio/adc/vf610_adc.c | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-) diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c index 4a10ae97dbf2..7ec21b5612ef 100644 --- a/drivers/iio/adc/vf610_adc.c +++ b/drivers/iio/adc/vf610_adc.c @@ -91,7 +91,7 @@ #define VF610_ADC_CAL 0x80 /* Other field define */ -#define VF610_ADC_ADCHC(x) ((x) & 0xF) +#define VF610_ADC_ADCHC(x) ((x) & 0x1F) #define VF610_ADC_AIEN (0x1 << 7) #define VF610_ADC_CONV_DISABLE 0x1F #define VF610_ADC_HS_COCO0 0x1 @@ -153,6 +153,12 @@ struct vf610_adc { BIT(IIO_CHAN_INFO_SAMP_FREQ), \ } +#define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) { \ + .type = (_chan_type), \ + .channel = (_idx), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \ +} + static const struct iio_chan_spec vf610_adc_iio_channels[] = { VF610_ADC_CHAN(0, IIO_VOLTAGE), VF610_ADC_CHAN(1, IIO_VOLTAGE), @@ -170,6 +176,7 @@ static const struct iio_chan_spec vf610_adc_iio_channels[] = { VF610_ADC_CHAN(13, IIO_VOLTAGE), VF610_ADC_CHAN(14, IIO_VOLTAGE), VF610_ADC_CHAN(15, IIO_VOLTAGE), + VF610_ADC_TEMPERATURE_CHAN(26, IIO_TEMP), /* sentinel */ }; @@ -451,6 +458,7 @@ static int vf610_read_raw(struct iio_dev *indio_dev, switch (mask) { case IIO_CHAN_INFO_RAW: + case IIO_CHAN_INFO_PROCESSED: mutex_lock(&indio_dev->mlock); reinit_completion(&info->completion); @@ -468,7 +476,23 @@ static int vf610_read_raw(struct iio_dev *indio_dev, return ret; } - *val = info->value; + switch (chan->type) { + case IIO_VOLTAGE: + *val = info->value; + break; + case IIO_TEMP: + /* + * Calculate in degree Celsius times 1000 + * Using sensor slope of 1.84 mV/°C and + * V at 25°C of 696 mV + */ + *val = 25000 - ((int)info->value - 864) * 1000000 / 1840; + break; + default: + mutex_unlock(&indio_dev->mlock); + return -EINVAL; + } + mutex_unlock(&indio_dev->mlock); return IIO_VAL_INT; -- cgit v1.2.3