diff options
author | Linus Walleij <linus.walleij@linaro.org> | 2016-12-30 23:54:18 +0100 |
---|---|---|
committer | Jonathan Cameron <jic23@kernel.org> | 2016-12-31 14:35:04 +0000 |
commit | 65e4345c8ef8811bbb4860fe5f2df10646b7f2e1 (patch) | |
tree | acbe27a1509fc0ed28dd6eeecbc6f9eb9723dafb /include | |
parent | 65c8aea07de11b6507efa175edb44bd8b4488218 (diff) |
iio: accel: st_accel: fix LIS3LV02 reading and scaling
The LIS3LV02 has a special bit that need to be set to get the
read values left aligned. Before this patch we get gibberish
like this:
iio_generic_buffer -a -c10 -n lis3lv02dl_accel
(...)
0.000000 -0.010042 -0.642688 19155832931907
0.000000 -0.010042 -0.642688 19155858751073
Which is because we read a raw value for 1g as 64 which is
the nominal 1024 for 1g shifted 4 bits to the left by being
right-aligned rather than left aligned.
Since all other sensors are left aligned, add some code to
set the special DAS (data alignment setting) bit to 1 so that
the right value is now read like this:
iio_generic_buffer -a -c10 -n lis3lv02dl_accel
(...)
0.000000 -0.147095 -10.120135 24761614364956
-0.029419 -0.176514 -10.120135 24761631624540
The scaling was weird as well: we have a gain of 1000 for 1g
and 3000 for 6g. I don't even remember how I came up with the
old values but they are wrong.
Fixes: 3acddf74f807 ("iio: st-sensors: add support for lis3lv02d accelerometer")
Cc: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Cc: Giuseppe Barba <giuseppe.barba@st.com>
Cc: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/iio/common/st_sensors.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/include/linux/iio/common/st_sensors.h b/include/linux/iio/common/st_sensors.h index 228bd44efa4c..497f2b3a5a62 100644 --- a/include/linux/iio/common/st_sensors.h +++ b/include/linux/iio/common/st_sensors.h @@ -116,6 +116,16 @@ struct st_sensor_bdu { }; /** + * struct st_sensor_das - ST sensor device data alignment selection + * @addr: address of the register. + * @mask: mask to write the das flag for left alignment. + */ +struct st_sensor_das { + u8 addr; + u8 mask; +}; + +/** * struct st_sensor_data_ready_irq - ST sensor device data-ready interrupt * @addr: address of the register. * @mask_int1: mask to enable/disable IRQ on INT1 pin. @@ -185,6 +195,7 @@ struct st_sensor_transfer_function { * @enable_axis: Enable one or more axis of the sensor. * @fs: Full scale register and full scale list available. * @bdu: Block data update register. + * @das: Data Alignment Selection register. * @drdy_irq: Data ready register of the sensor. * @multi_read_bit: Use or not particular bit for [I2C/SPI] multi-read. * @bootime: samples to discard when sensor passing from power-down to power-up. @@ -200,6 +211,7 @@ struct st_sensor_settings { struct st_sensor_axis enable_axis; struct st_sensor_fullscale fs; struct st_sensor_bdu bdu; + struct st_sensor_das das; struct st_sensor_data_ready_irq drdy_irq; bool multi_read_bit; unsigned int bootime; |