From: Lars-Peter Clausen <lars@metafoo.de>
To: Jonathan Cameron <jic23@kernel.org>
Cc: linux-iio@vger.kernel.org, Lars-Peter Clausen <lars@metafoo.de>
Subject: [PATCH 10/25] iio:ad5764: Report scale as fractional value
Date: Sat, 28 Sep 2013 11:31:42 +0200 [thread overview]
Message-ID: <1380360717-26103-10-git-send-email-lars@metafoo.de> (raw)
In-Reply-To: <1380360717-26103-1-git-send-email-lars@metafoo.de>
Move the complexity of calculating the fixed point scale to the core.
Also fix a off by one error in the comment describing the transfer function.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
drivers/iio/dac/ad5764.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/iio/dac/ad5764.c b/drivers/iio/dac/ad5764.c
index df7e028..a8ff5b2 100644
--- a/drivers/iio/dac/ad5764.c
+++ b/drivers/iio/dac/ad5764.c
@@ -217,7 +217,6 @@ static int ad5764_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val, int *val2, long info)
{
struct ad5764_state *st = iio_priv(indio_dev);
- unsigned long scale_uv;
unsigned int reg;
int vref;
int ret;
@@ -245,15 +244,14 @@ static int ad5764_read_raw(struct iio_dev *indio_dev,
*val = sign_extend32(*val, 5);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
- /* vout = 4 * vref + ((dac_code / 65535) - 0.5) */
+ /* vout = 4 * vref + ((dac_code / 65536) - 0.5) */
vref = ad5764_get_channel_vref(st, chan->channel);
if (vref < 0)
return vref;
- scale_uv = (vref * 4 * 100) >> chan->scan_type.realbits;
- *val = scale_uv / 100000;
- *val2 = (scale_uv % 100000) * 10;
- return IIO_VAL_INT_PLUS_MICRO;
+ *val = vref * 4 / 1000;
+ *val2 = chan->scan_type.realbits;
+ return IIO_VAL_FRACTIONAL_LOG2;
case IIO_CHAN_INFO_OFFSET:
*val = -(1 << chan->scan_type.realbits) / 2;
return IIO_VAL_INT;
--
1.8.0
next prev parent reply other threads:[~2013-09-28 9:31 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-28 9:31 [PATCH 01/25] iio:ad5064: Report scale as fractional value Lars-Peter Clausen
2013-09-28 9:31 ` [PATCH 02/25] iio:ad5360: " Lars-Peter Clausen
2013-10-01 8:48 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 03/25] iio:ad5380: " Lars-Peter Clausen
2013-10-01 8:49 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 04/25] iio:ad5421: " Lars-Peter Clausen
2013-10-01 8:50 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 05/25] iio:ad5446: " Lars-Peter Clausen
2013-10-01 8:51 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 06/25] iio:ad5504: " Lars-Peter Clausen
2013-10-01 8:52 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 07/25] iio:ad5624r: " Lars-Peter Clausen
2013-10-01 8:52 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 08/25] iio:ad5686: " Lars-Peter Clausen
2013-10-01 8:53 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 09/25] iio:ad5755: " Lars-Peter Clausen
2013-10-01 8:53 ` Jonathan Cameron
2013-09-28 9:31 ` Lars-Peter Clausen [this message]
2013-10-01 8:54 ` [PATCH 10/25] iio:ad5764: " Jonathan Cameron
2013-09-28 9:31 ` [PATCH 11/25] iio:ad5791: " Lars-Peter Clausen
2013-10-01 9:01 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 12/25] iio:max517: " Lars-Peter Clausen
2013-10-01 9:03 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 13/25] iio:mcp4725: " Lars-Peter Clausen
2013-09-28 9:31 ` [PATCH 14/25] iio:ad7266: " Lars-Peter Clausen
2013-10-01 9:05 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 15/25] iio:ad7476: " Lars-Peter Clausen
2013-10-01 9:06 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 16/25] iio:ad7791: " Lars-Peter Clausen
2013-10-01 9:07 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 17/25] iio:at91: " Lars-Peter Clausen
2013-10-01 9:07 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 18/25] iio:max1363: " Lars-Peter Clausen
2013-10-01 9:08 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 19/25] staging:iio:ad7280a: " Lars-Peter Clausen
2013-10-01 9:09 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 20/25] staging:iio:ad7606: " Lars-Peter Clausen
2013-10-01 9:10 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 21/25] staging:iio:ad7780: " Lars-Peter Clausen
2013-10-01 9:10 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 22/25] staging:iio:ad799x: " Lars-Peter Clausen
2013-10-01 9:11 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 23/25] staging:iio:ad7746: " Lars-Peter Clausen
2013-10-01 9:12 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 24/25] staging:iio:spear_adc: " Lars-Peter Clausen
2013-10-01 9:13 ` Jonathan Cameron
2013-09-28 9:31 ` [PATCH 25/25] iio: Update unit of the voltage scale in the documentation Lars-Peter Clausen
2013-10-01 9:14 ` Jonathan Cameron
2013-10-01 8:46 ` [PATCH 01/25] iio:ad5064: Report scale as fractional value Jonathan Cameron
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