[PATCH 03/21] iio: ti_am335x_adc: Added iio_voltageX_scale

From: Zubair Lutfullah
Date: Wed Jul 17 2013 - 13:32:40 EST


in_voltageX_scale is supposed to give scaled voltages. This was
missing in the driver and has been added.
Current patch is fixed to scale for 1.8V AVDD.

Signed-off-by: Zubair Lutfullah <zubair.lutfullah@xxxxxxxxx>
---
drivers/iio/adc/ti_am335x_adc.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index 1f83cf7..8a63203 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -26,7 +26,7 @@
#include <linux/of_device.h>
#include <linux/iio/machine.h>
#include <linux/iio/driver.h>
-
+#include <linux/math64.h>
#include <linux/mfd/ti_am335x_tscadc.h>

struct tiadc_device {
@@ -118,7 +118,8 @@ static int tiadc_channel_init(struct iio_dev *indio_dev, int channels)
chan->type = IIO_VOLTAGE;
chan->indexed = 1;
chan->channel = adc_dev->channel_line[i];
- chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
+ chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE);
chan->datasheet_name = chan_name_ain[chan->channel];
chan->scan_type.sign = 'u';
chan->scan_type.realbits = 12;
@@ -190,6 +191,18 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
}
}

+ switch (mask){
+ case IIO_CHAN_INFO_RAW : /*Do nothing. Above code works fine.*/
+ break;
+ case IIO_CHAN_INFO_SCALE : {
+ /*12 Bit adc. Scale value for 1800mV AVDD. Ideally
+ AVDD should come from DT.*/
+ *val = div_u64( (u64)(*val) * 1800 , 4096);
+ break;
+ }
+ default: break;
+ }
+
if (found == false)
return -EBUSY;
return IIO_VAL_INT;
--
1.7.9.5

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