Commit Graph

6 Commits

Author SHA1 Message Date
Peter Rosin
6a6e1d56a0 iio: pressure: mpl115: do not rely on structure field ordering
Fixes a regression triggered by a change in the layout of
struct iio_chan_spec, but the real bug is in the driver which assumed
a specific structure layout in the first place. Hint: the three bits were
not OR:ed together as implied by the indentation prior to this patch,
there was a comma between the first two, which accidentally moved the
..._SCALE and ..._OFFSET bits to the next structure field. That field
was .info_mask_shared_by_type before the _available attributes was added
by commit 5123960007 ("iio:core: add a callback to allow drivers to
provide _available attributes") and .info_mask_separate_available
afterwards, and the regression happened.

info_mask_shared_by_type is actually a better choice than the originally
intended info_mask_separate for the ..._SCALE and ..._OFFSET bits since
a constant is returned from mpl115_read_raw for the scale/offset. Using
info_mask_shared_by_type also preserves the behavior from before the
regression and is therefore less likely to cause other interesting side
effects.

The above mentioned regression causes unintended sysfs attibutes to
show up that are not backed by code, in turn causing a NULL pointer
defererence to happen on access.

Fixes: 3017d90e89 ("iio: Add Freescale MPL115A2 pressure / temperature sensor driver")
Fixes: 5123960007 ("iio:core: add a callback to allow drivers to provide _available attributes")
Signed-off-by: Peter Rosin <peda@axentia.se>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-02-11 09:00:44 +00:00
Greg Kroah-Hartman
5ba907a949 Merge 4.5-rc3 into staging-next
We want the upstream staging fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07 17:34:04 -08:00
Akinobu Mita
c984b9cbbd iio: pressure: mpl115: support MPL115A1
mpl115 driver currently supports i2c interface (MPL115A2).
There is also SPI version (MPL115A1).  The difference between them
is only physical transport so we can easily support both while sharing
most of the code.

Split the driver into a core support module and one module each for I2C
and SPI support.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Peter Meerwald <pmeerw@pmeerw.net>
Cc: linux-iio@vger.kernel.org
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-01-30 16:27:12 +00:00
Akinobu Mita
0b767b3188 iio: pressure: mpl115: don't set unused i2c clientdata
mpl115 sets i2c clientdata, but it is not used anywhere.  So remove it.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Peter Meerwald <pmeerw@pmeerw.net>
Cc: linux-iio@vger.kernel.org
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-01-30 16:27:11 +00:00
Akinobu Mita
431386e783 iio: pressure: mpl115: fix temperature offset sign
According to the datasheet, the resolusion of temperature sensor is
-5.35 counts/C. Temperature ADC is 472 counts at 25C.
(https://www.sparkfun.com/datasheets/Sensors/Pressure/MPL115A1.pdf
NOTE: This is older revision, but this information is removed from the
latest datasheet from nxp somehow)

Temp [C] = (Tadc - 472) / -5.35 + 25
         = (Tadc - 605.750000) * -0.186915888

So the correct offset is -605.750000.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-01-30 16:07:32 +00:00
Peter Meerwald
3017d90e89 iio: Add Freescale MPL115A2 pressure / temperature sensor driver
I2C-controlled sensor with 10-bit pressure and temperature measurement

datasheet: http://cache.freescale.com/files/sensors/doc/data_sheet/MPL3115A2.pdf

v2:
* use devm_iio_device_register()

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-05-03 11:31:36 +01:00