Re: [PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-14 Thread Gergely Imreh
On 14 June 2015 at 23:55, Jonathan Cameron  wrote:
> On 14/06/15 16:45, Lars-Peter Clausen wrote:
>> On 06/14/2015 05:15 AM, Gergely Imreh wrote:
>>> On 14 June 2015 at 02:30, Jonathan Cameron  wrote:
 On 11/06/15 09:22, Gergely Imreh wrote:
> The Xilinx XADC driver has both a temperature channel and 8 voltage
> channels. The voltage channels have no offset, but actually were still
> set the same offset as the temperature channel. This did not cause
> problems in /sys/bus/iio/ but can cause problems with other drivers
> using iio data. For example iio-hwmon did return wrong voltage values
> because of the offset.
>
> Change tested with the Parallella board.
>
> Signed-off-by: Gergely Imreh 
 Well spotted on the bug, but I think we are better off fixing this at the
 true source of the problem which is in drivers/iio/inkern.c
 iio_convert_raw_to_processed_unlocked which does a call to
 iio_channel_read(chan, , NULL, IIO_CHAN_INFO_OFFSET) then uses
 the error return to check if the offset parameter is available. It should
 be checking that before making this call with a call to 
 iio_channel_has_info.

 I don't suppose you could prepare a patch fixing that as you found the 
 problem?
>>>
>>> I'll check it out, and send an updated patch! Thanks for the pointers
>>> to the core of the issue.
>>
>> The issue was already fixed a while ago, see this patch:
>> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=65de7654d39c70c2b942f801cea01590cf7e3458
>>
>>  Starting with that commit iio_channel_read() returns an error when
>> the attribute is not available, which causes
>> iio_convert_raw_to_processed_unlocked() to skip the offset if it is
>> not available.
>>
> oops.  Good spot. I'd completely forgotten about that and failed to spot
> the check when looking at the code yesterday.
>
> Glad you were keeping an eagle eye on things ;)

Okay, thanks, then it's all good, scrub this patch!
That linked change was not backported to the Parallella yet, and
missed it. Looks like it's going to be included now.

Thanks for the feedback!
   Greg

>
> J
>> - Lars
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Re: [PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-14 Thread Jonathan Cameron
On 14/06/15 16:45, Lars-Peter Clausen wrote:
> On 06/14/2015 05:15 AM, Gergely Imreh wrote:
>> On 14 June 2015 at 02:30, Jonathan Cameron  wrote:
>>> On 11/06/15 09:22, Gergely Imreh wrote:
 The Xilinx XADC driver has both a temperature channel and 8 voltage
 channels. The voltage channels have no offset, but actually were still
 set the same offset as the temperature channel. This did not cause
 problems in /sys/bus/iio/ but can cause problems with other drivers
 using iio data. For example iio-hwmon did return wrong voltage values
 because of the offset.

 Change tested with the Parallella board.

 Signed-off-by: Gergely Imreh 
>>> Well spotted on the bug, but I think we are better off fixing this at the
>>> true source of the problem which is in drivers/iio/inkern.c
>>> iio_convert_raw_to_processed_unlocked which does a call to
>>> iio_channel_read(chan, , NULL, IIO_CHAN_INFO_OFFSET) then uses
>>> the error return to check if the offset parameter is available. It should
>>> be checking that before making this call with a call to 
>>> iio_channel_has_info.
>>>
>>> I don't suppose you could prepare a patch fixing that as you found the 
>>> problem?
>>
>> I'll check it out, and send an updated patch! Thanks for the pointers
>> to the core of the issue.
> 
> The issue was already fixed a while ago, see this patch: 
> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=65de7654d39c70c2b942f801cea01590cf7e3458
>
>  Starting with that commit iio_channel_read() returns an error when
> the attribute is not available, which causes
> iio_convert_raw_to_processed_unlocked() to skip the offset if it is
> not available.
> 
oops.  Good spot. I'd completely forgotten about that and failed to spot
the check when looking at the code yesterday.

Glad you were keeping an eagle eye on things ;)

J
> - Lars
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Re: [PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-14 Thread Lars-Peter Clausen

On 06/14/2015 05:15 AM, Gergely Imreh wrote:

On 14 June 2015 at 02:30, Jonathan Cameron  wrote:

On 11/06/15 09:22, Gergely Imreh wrote:

The Xilinx XADC driver has both a temperature channel and 8 voltage
channels. The voltage channels have no offset, but actually were still
set the same offset as the temperature channel. This did not cause
problems in /sys/bus/iio/ but can cause problems with other drivers
using iio data. For example iio-hwmon did return wrong voltage values
because of the offset.

Change tested with the Parallella board.

Signed-off-by: Gergely Imreh 

Well spotted on the bug, but I think we are better off fixing this at the
true source of the problem which is in drivers/iio/inkern.c
iio_convert_raw_to_processed_unlocked which does a call to
iio_channel_read(chan, , NULL, IIO_CHAN_INFO_OFFSET) then uses
the error return to check if the offset parameter is available. It should
be checking that before making this call with a call to iio_channel_has_info.

I don't suppose you could prepare a patch fixing that as you found the problem?


I'll check it out, and send an updated patch! Thanks for the pointers
to the core of the issue.


The issue was already fixed a while ago, see this patch:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=65de7654d39c70c2b942f801cea01590cf7e3458

Starting with that commit iio_channel_read() returns an error when the 
attribute is not available, which causes 
iio_convert_raw_to_processed_unlocked() to skip the offset if it is not 
available.


- Lars
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Re: [PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-14 Thread Lars-Peter Clausen

On 06/14/2015 05:15 AM, Gergely Imreh wrote:

On 14 June 2015 at 02:30, Jonathan Cameron ji...@kernel.org wrote:

On 11/06/15 09:22, Gergely Imreh wrote:

The Xilinx XADC driver has both a temperature channel and 8 voltage
channels. The voltage channels have no offset, but actually were still
set the same offset as the temperature channel. This did not cause
problems in /sys/bus/iio/ but can cause problems with other drivers
using iio data. For example iio-hwmon did return wrong voltage values
because of the offset.

Change tested with the Parallella board.

Signed-off-by: Gergely Imreh imr...@gmail.com

Well spotted on the bug, but I think we are better off fixing this at the
true source of the problem which is in drivers/iio/inkern.c
iio_convert_raw_to_processed_unlocked which does a call to
iio_channel_read(chan, offset, NULL, IIO_CHAN_INFO_OFFSET) then uses
the error return to check if the offset parameter is available. It should
be checking that before making this call with a call to iio_channel_has_info.

I don't suppose you could prepare a patch fixing that as you found the problem?


I'll check it out, and send an updated patch! Thanks for the pointers
to the core of the issue.


The issue was already fixed a while ago, see this patch:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=65de7654d39c70c2b942f801cea01590cf7e3458

Starting with that commit iio_channel_read() returns an error when the 
attribute is not available, which causes 
iio_convert_raw_to_processed_unlocked() to skip the offset if it is not 
available.


- Lars
--
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Re: [PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-14 Thread Jonathan Cameron
On 14/06/15 16:45, Lars-Peter Clausen wrote:
 On 06/14/2015 05:15 AM, Gergely Imreh wrote:
 On 14 June 2015 at 02:30, Jonathan Cameron ji...@kernel.org wrote:
 On 11/06/15 09:22, Gergely Imreh wrote:
 The Xilinx XADC driver has both a temperature channel and 8 voltage
 channels. The voltage channels have no offset, but actually were still
 set the same offset as the temperature channel. This did not cause
 problems in /sys/bus/iio/ but can cause problems with other drivers
 using iio data. For example iio-hwmon did return wrong voltage values
 because of the offset.

 Change tested with the Parallella board.

 Signed-off-by: Gergely Imreh imr...@gmail.com
 Well spotted on the bug, but I think we are better off fixing this at the
 true source of the problem which is in drivers/iio/inkern.c
 iio_convert_raw_to_processed_unlocked which does a call to
 iio_channel_read(chan, offset, NULL, IIO_CHAN_INFO_OFFSET) then uses
 the error return to check if the offset parameter is available. It should
 be checking that before making this call with a call to 
 iio_channel_has_info.

 I don't suppose you could prepare a patch fixing that as you found the 
 problem?

 I'll check it out, and send an updated patch! Thanks for the pointers
 to the core of the issue.
 
 The issue was already fixed a while ago, see this patch: 
 http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=65de7654d39c70c2b942f801cea01590cf7e3458

  Starting with that commit iio_channel_read() returns an error when
 the attribute is not available, which causes
 iio_convert_raw_to_processed_unlocked() to skip the offset if it is
 not available.
 
oops.  Good spot. I'd completely forgotten about that and failed to spot
the check when looking at the code yesterday.

Glad you were keeping an eagle eye on things ;)

J
 - Lars
--
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the body of a message to majord...@vger.kernel.org
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Re: [PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-14 Thread Gergely Imreh
On 14 June 2015 at 23:55, Jonathan Cameron ji...@kernel.org wrote:
 On 14/06/15 16:45, Lars-Peter Clausen wrote:
 On 06/14/2015 05:15 AM, Gergely Imreh wrote:
 On 14 June 2015 at 02:30, Jonathan Cameron ji...@kernel.org wrote:
 On 11/06/15 09:22, Gergely Imreh wrote:
 The Xilinx XADC driver has both a temperature channel and 8 voltage
 channels. The voltage channels have no offset, but actually were still
 set the same offset as the temperature channel. This did not cause
 problems in /sys/bus/iio/ but can cause problems with other drivers
 using iio data. For example iio-hwmon did return wrong voltage values
 because of the offset.

 Change tested with the Parallella board.

 Signed-off-by: Gergely Imreh imr...@gmail.com
 Well spotted on the bug, but I think we are better off fixing this at the
 true source of the problem which is in drivers/iio/inkern.c
 iio_convert_raw_to_processed_unlocked which does a call to
 iio_channel_read(chan, offset, NULL, IIO_CHAN_INFO_OFFSET) then uses
 the error return to check if the offset parameter is available. It should
 be checking that before making this call with a call to 
 iio_channel_has_info.

 I don't suppose you could prepare a patch fixing that as you found the 
 problem?

 I'll check it out, and send an updated patch! Thanks for the pointers
 to the core of the issue.

 The issue was already fixed a while ago, see this patch:
 http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=65de7654d39c70c2b942f801cea01590cf7e3458

  Starting with that commit iio_channel_read() returns an error when
 the attribute is not available, which causes
 iio_convert_raw_to_processed_unlocked() to skip the offset if it is
 not available.

 oops.  Good spot. I'd completely forgotten about that and failed to spot
 the check when looking at the code yesterday.

 Glad you were keeping an eagle eye on things ;)

Okay, thanks, then it's all good, scrub this patch!
That linked change was not backported to the Parallella yet, and
missed it. Looks like it's going to be included now.

Thanks for the feedback!
   Greg


 J
 - Lars
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Re: [PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-13 Thread Gergely Imreh
On 14 June 2015 at 02:30, Jonathan Cameron  wrote:
> On 11/06/15 09:22, Gergely Imreh wrote:
>> The Xilinx XADC driver has both a temperature channel and 8 voltage
>> channels. The voltage channels have no offset, but actually were still
>> set the same offset as the temperature channel. This did not cause
>> problems in /sys/bus/iio/ but can cause problems with other drivers
>> using iio data. For example iio-hwmon did return wrong voltage values
>> because of the offset.
>>
>> Change tested with the Parallella board.
>>
>> Signed-off-by: Gergely Imreh 
> Well spotted on the bug, but I think we are better off fixing this at the
> true source of the problem which is in drivers/iio/inkern.c
> iio_convert_raw_to_processed_unlocked which does a call to
> iio_channel_read(chan, , NULL, IIO_CHAN_INFO_OFFSET) then uses
> the error return to check if the offset parameter is available. It should
> be checking that before making this call with a call to iio_channel_has_info.
>
> I don't suppose you could prepare a patch fixing that as you found the 
> problem?

I'll check it out, and send an updated patch! Thanks for the pointers
to the core of the issue.

>
> If not I can fix it up sometime if no one else beats me to it.
>
> Thanks
>
> Jonathan
>> ---
>>  drivers/iio/adc/xilinx-xadc-core.c | 14 +++---
>>  1 file changed, 11 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/iio/adc/xilinx-xadc-core.c 
>> b/drivers/iio/adc/xilinx-xadc-core.c
>> index ab52be2..36efab7 100644
>> --- a/drivers/iio/adc/xilinx-xadc-core.c
>> +++ b/drivers/iio/adc/xilinx-xadc-core.c
>> @@ -877,9 +877,17 @@ static int xadc_read_raw(struct iio_dev *indio_dev,
>>   return -EINVAL;
>>   }
>>   case IIO_CHAN_INFO_OFFSET:
>> - /* Only the temperature channel has an offset */
>> - *val = -((273150 << 12) / 503975);
>> - return IIO_VAL_INT;
>> + switch (chan->type) {
>> + case IIO_VOLTAGE:
>> + *val = 0;
>> + return IIO_VAL_INT;
>> + case IIO_TEMP:
>> + /* Only the temperature channel has an offset */
>> + *val = -((273150 << 12) / 503975);
>> + return IIO_VAL_INT;
>> + default:
>> + return -EINVAL;
>> + }
>>   case IIO_CHAN_INFO_SAMP_FREQ:
>>   ret = xadc_read_adc_reg(xadc, XADC_REG_CONF2, );
>>   if (ret)
>>
>
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Re: [PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-13 Thread Jonathan Cameron
On 11/06/15 09:22, Gergely Imreh wrote:
> The Xilinx XADC driver has both a temperature channel and 8 voltage
> channels. The voltage channels have no offset, but actually were still
> set the same offset as the temperature channel. This did not cause
> problems in /sys/bus/iio/ but can cause problems with other drivers
> using iio data. For example iio-hwmon did return wrong voltage values
> because of the offset.
> 
> Change tested with the Parallella board.
> 
> Signed-off-by: Gergely Imreh 
Well spotted on the bug, but I think we are better off fixing this at the
true source of the problem which is in drivers/iio/inkern.c 
iio_convert_raw_to_processed_unlocked which does a call to 
iio_channel_read(chan, , NULL, IIO_CHAN_INFO_OFFSET) then uses
the error return to check if the offset parameter is available. It should
be checking that before making this call with a call to iio_channel_has_info.

I don't suppose you could prepare a patch fixing that as you found the problem?

If not I can fix it up sometime if no one else beats me to it.

Thanks

Jonathan
> ---
>  drivers/iio/adc/xilinx-xadc-core.c | 14 +++---
>  1 file changed, 11 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/iio/adc/xilinx-xadc-core.c 
> b/drivers/iio/adc/xilinx-xadc-core.c
> index ab52be2..36efab7 100644
> --- a/drivers/iio/adc/xilinx-xadc-core.c
> +++ b/drivers/iio/adc/xilinx-xadc-core.c
> @@ -877,9 +877,17 @@ static int xadc_read_raw(struct iio_dev *indio_dev,
>   return -EINVAL;
>   }
>   case IIO_CHAN_INFO_OFFSET:
> - /* Only the temperature channel has an offset */
> - *val = -((273150 << 12) / 503975);
> - return IIO_VAL_INT;
> + switch (chan->type) {
> + case IIO_VOLTAGE:
> + *val = 0;
> + return IIO_VAL_INT;
> + case IIO_TEMP:
> + /* Only the temperature channel has an offset */
> + *val = -((273150 << 12) / 503975);
> + return IIO_VAL_INT;
> + default:
> + return -EINVAL;
> + }
>   case IIO_CHAN_INFO_SAMP_FREQ:
>   ret = xadc_read_adc_reg(xadc, XADC_REG_CONF2, );
>   if (ret)
> 

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Re: [PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-13 Thread Gergely Imreh
On 14 June 2015 at 02:30, Jonathan Cameron ji...@kernel.org wrote:
 On 11/06/15 09:22, Gergely Imreh wrote:
 The Xilinx XADC driver has both a temperature channel and 8 voltage
 channels. The voltage channels have no offset, but actually were still
 set the same offset as the temperature channel. This did not cause
 problems in /sys/bus/iio/ but can cause problems with other drivers
 using iio data. For example iio-hwmon did return wrong voltage values
 because of the offset.

 Change tested with the Parallella board.

 Signed-off-by: Gergely Imreh imr...@gmail.com
 Well spotted on the bug, but I think we are better off fixing this at the
 true source of the problem which is in drivers/iio/inkern.c
 iio_convert_raw_to_processed_unlocked which does a call to
 iio_channel_read(chan, offset, NULL, IIO_CHAN_INFO_OFFSET) then uses
 the error return to check if the offset parameter is available. It should
 be checking that before making this call with a call to iio_channel_has_info.

 I don't suppose you could prepare a patch fixing that as you found the 
 problem?

I'll check it out, and send an updated patch! Thanks for the pointers
to the core of the issue.


 If not I can fix it up sometime if no one else beats me to it.

 Thanks

 Jonathan
 ---
  drivers/iio/adc/xilinx-xadc-core.c | 14 +++---
  1 file changed, 11 insertions(+), 3 deletions(-)

 diff --git a/drivers/iio/adc/xilinx-xadc-core.c 
 b/drivers/iio/adc/xilinx-xadc-core.c
 index ab52be2..36efab7 100644
 --- a/drivers/iio/adc/xilinx-xadc-core.c
 +++ b/drivers/iio/adc/xilinx-xadc-core.c
 @@ -877,9 +877,17 @@ static int xadc_read_raw(struct iio_dev *indio_dev,
   return -EINVAL;
   }
   case IIO_CHAN_INFO_OFFSET:
 - /* Only the temperature channel has an offset */
 - *val = -((273150  12) / 503975);
 - return IIO_VAL_INT;
 + switch (chan-type) {
 + case IIO_VOLTAGE:
 + *val = 0;
 + return IIO_VAL_INT;
 + case IIO_TEMP:
 + /* Only the temperature channel has an offset */
 + *val = -((273150  12) / 503975);
 + return IIO_VAL_INT;
 + default:
 + return -EINVAL;
 + }
   case IIO_CHAN_INFO_SAMP_FREQ:
   ret = xadc_read_adc_reg(xadc, XADC_REG_CONF2, val16);
   if (ret)


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Re: [PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-13 Thread Jonathan Cameron
On 11/06/15 09:22, Gergely Imreh wrote:
 The Xilinx XADC driver has both a temperature channel and 8 voltage
 channels. The voltage channels have no offset, but actually were still
 set the same offset as the temperature channel. This did not cause
 problems in /sys/bus/iio/ but can cause problems with other drivers
 using iio data. For example iio-hwmon did return wrong voltage values
 because of the offset.
 
 Change tested with the Parallella board.
 
 Signed-off-by: Gergely Imreh imr...@gmail.com
Well spotted on the bug, but I think we are better off fixing this at the
true source of the problem which is in drivers/iio/inkern.c 
iio_convert_raw_to_processed_unlocked which does a call to 
iio_channel_read(chan, offset, NULL, IIO_CHAN_INFO_OFFSET) then uses
the error return to check if the offset parameter is available. It should
be checking that before making this call with a call to iio_channel_has_info.

I don't suppose you could prepare a patch fixing that as you found the problem?

If not I can fix it up sometime if no one else beats me to it.

Thanks

Jonathan
 ---
  drivers/iio/adc/xilinx-xadc-core.c | 14 +++---
  1 file changed, 11 insertions(+), 3 deletions(-)
 
 diff --git a/drivers/iio/adc/xilinx-xadc-core.c 
 b/drivers/iio/adc/xilinx-xadc-core.c
 index ab52be2..36efab7 100644
 --- a/drivers/iio/adc/xilinx-xadc-core.c
 +++ b/drivers/iio/adc/xilinx-xadc-core.c
 @@ -877,9 +877,17 @@ static int xadc_read_raw(struct iio_dev *indio_dev,
   return -EINVAL;
   }
   case IIO_CHAN_INFO_OFFSET:
 - /* Only the temperature channel has an offset */
 - *val = -((273150  12) / 503975);
 - return IIO_VAL_INT;
 + switch (chan-type) {
 + case IIO_VOLTAGE:
 + *val = 0;
 + return IIO_VAL_INT;
 + case IIO_TEMP:
 + /* Only the temperature channel has an offset */
 + *val = -((273150  12) / 503975);
 + return IIO_VAL_INT;
 + default:
 + return -EINVAL;
 + }
   case IIO_CHAN_INFO_SAMP_FREQ:
   ret = xadc_read_adc_reg(xadc, XADC_REG_CONF2, val16);
   if (ret)
 

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[PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-11 Thread Gergely Imreh
The Xilinx XADC driver has both a temperature channel and 8 voltage
channels. The voltage channels have no offset, but actually were still
set the same offset as the temperature channel. This did not cause
problems in /sys/bus/iio/ but can cause problems with other drivers
using iio data. For example iio-hwmon did return wrong voltage values
because of the offset.

Change tested with the Parallella board.

Signed-off-by: Gergely Imreh 
---
 drivers/iio/adc/xilinx-xadc-core.c | 14 +++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/adc/xilinx-xadc-core.c 
b/drivers/iio/adc/xilinx-xadc-core.c
index ab52be2..36efab7 100644
--- a/drivers/iio/adc/xilinx-xadc-core.c
+++ b/drivers/iio/adc/xilinx-xadc-core.c
@@ -877,9 +877,17 @@ static int xadc_read_raw(struct iio_dev *indio_dev,
return -EINVAL;
}
case IIO_CHAN_INFO_OFFSET:
-   /* Only the temperature channel has an offset */
-   *val = -((273150 << 12) / 503975);
-   return IIO_VAL_INT;
+   switch (chan->type) {
+   case IIO_VOLTAGE:
+   *val = 0;
+   return IIO_VAL_INT;
+   case IIO_TEMP:
+   /* Only the temperature channel has an offset */
+   *val = -((273150 << 12) / 503975);
+   return IIO_VAL_INT;
+   default:
+   return -EINVAL;
+   }
case IIO_CHAN_INFO_SAMP_FREQ:
ret = xadc_read_adc_reg(xadc, XADC_REG_CONF2, );
if (ret)
-- 
2.4.2

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[PATCH 1/1] iio:adc: XADC: Set offset explicitly to zero on voltage channels

2015-06-11 Thread Gergely Imreh
The Xilinx XADC driver has both a temperature channel and 8 voltage
channels. The voltage channels have no offset, but actually were still
set the same offset as the temperature channel. This did not cause
problems in /sys/bus/iio/ but can cause problems with other drivers
using iio data. For example iio-hwmon did return wrong voltage values
because of the offset.

Change tested with the Parallella board.

Signed-off-by: Gergely Imreh imr...@gmail.com
---
 drivers/iio/adc/xilinx-xadc-core.c | 14 +++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/adc/xilinx-xadc-core.c 
b/drivers/iio/adc/xilinx-xadc-core.c
index ab52be2..36efab7 100644
--- a/drivers/iio/adc/xilinx-xadc-core.c
+++ b/drivers/iio/adc/xilinx-xadc-core.c
@@ -877,9 +877,17 @@ static int xadc_read_raw(struct iio_dev *indio_dev,
return -EINVAL;
}
case IIO_CHAN_INFO_OFFSET:
-   /* Only the temperature channel has an offset */
-   *val = -((273150  12) / 503975);
-   return IIO_VAL_INT;
+   switch (chan-type) {
+   case IIO_VOLTAGE:
+   *val = 0;
+   return IIO_VAL_INT;
+   case IIO_TEMP:
+   /* Only the temperature channel has an offset */
+   *val = -((273150  12) / 503975);
+   return IIO_VAL_INT;
+   default:
+   return -EINVAL;
+   }
case IIO_CHAN_INFO_SAMP_FREQ:
ret = xadc_read_adc_reg(xadc, XADC_REG_CONF2, val16);
if (ret)
-- 
2.4.2

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