Re: [PATCH v5 0/4] iio: Add support for rotation from north

From: Reyad Attiyat
Date: Wed Jul 09 2014 - 18:13:26 EST

Hey Srinivas,

I did look into the panic you sent. I wasn't sure exactly what caused
the NULL pointer.
I tested it with out applying the last rotation from north patch, so
no hid usages are found, my device only has rotation_from_north, and
hid_parse_report() would return -EINVAL.
I added another check to make sure a iio channel were set up, and
return -EINVAL if not, but couldn't think of anything else.

Could you test this version with dynamic debugging and see if it is
finding any hid usage attributes.
Any ideas what could cause this? I think I'm handling errors properly
by returning what parse_report returns (-EINVAL or -ENOMEM) in probe

Reyad Attiyat

On Wed, Jul 9, 2014 at 2:45 PM, Srinivas Pandruvada
<srinivas.pandruvada@xxxxxxxxxxxxxxx> wrote:
> On 07/09/2014 12:30 PM, Reyad Attiyat wrote:
>> This series of patches modifies magn-3d driver to handle the rotation
>> from north usage. This is done by scanning the report and then building
>> the iio arrays (vals and channels) dynamically.
>> Changes from V4
>> I use the address field of struct iio_chan_spec to hold the array index
>> of the usage attribute. The scan_index field is generated when creating
>> an iio channel.
>> Reyad Attiyat (4):
>> iio: Documentation: Add documentation for rotation from north sensor
>> usage attributes
>> iio: types: Added support for rotation from north usage attributes
>> iio: hid-sensor-magn-3d: Scan for usage attributes before setting up
>> iio channels
>> iio: hid-sensor-magn-3d: Add support for rotation from north
>> Documentation/ABI/testing/sysfs-bus-iio | 82 +++++++++++
>> drivers/iio/industrialio-core.c | 4 +
>> drivers/iio/magnetometer/hid-sensor-magn-3d.c | 199
>> ++++++++++++++++++++------
>> include/linux/iio/types.h | 4 +
>> 4 files changed, 245 insertions(+), 44 deletions(-)
> Did you get chance to look at the cause of panic?
> Thanks,
> Srinivas
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