linux-toradex.git/drivers/iio, branch v4.10

iio: dht11: Use usleep_range instead of msleep for start signal

2017-01-22T13:35:40+00:00

The DHT22 (AM2302) datasheet specifies that the LOW start pulse should not
exceed 20ms. However, observations with an oscilloscope of an RPi Model 2B
(rev 1.1) communicating with a DHT22 sensor showed that the driver was
consistently sending start pulses longer than 20ms:

Kernel 4.7.10-v7+ (n=132):
    Minimum pulse length: 20.20ms
    Maximum:              29.84ms
    Mean:                 24.96ms
    StDev:                2.82ms
    Sensor response rate: 100%
    Read success rate:    76%

On kernel 4.8, the start pulse was so long that the sensor would not even
respond 97% of the time:

Kernel 4.8.16-v7+ (n=100):
    Minimum pulse length: 30.4ms
    Maximum:              74.4ms
    Mean:                 39.3ms
    StDev:                10.2ms
    Sensor response rate: 3%
    Read success rate:    3%

The driver would return ETIMEDOUT and write log messages like this:

[   51.430987] dht11 dht11@0: Only 1 signal edges detected
[   66.311019] dht11 dht11@0: Only 0 signal edges detected

Replacing msleep(18) with usleep_range(18000, 20000) made the pulse length
sane again and restored responsiveness:

Kernel 4.8.16-v7+ with usleep_range (n=123):
    Minimum pulse length: 18.16ms
    Maximum:              20.20ms
    Mean:                 19.85ms
    StDev:                0.51ms
    Sensor response rate: 100%
    Read success rate:    84%

Cc: stable@vger.kernel.org
Signed-off-by: John Brooks 
Reviewed-by: Harald Geyer 
Signed-off-by: Jonathan Cameron

iio: adc: palmas_gpadc: retrieve a valid iio_dev in suspend/resume

2017-01-21T14:26:03+00:00

The suspend/resume functions were using dev_to_iio_dev() to get
the iio_dev. That only works on IIO dev's.  Use dev_get_drvdata()
for a platform device to get the correct iio_dev.

Signed-off-by: Alison Schofield 
Cc: 
Signed-off-by: Jonathan Cameron

iio: health: max30100: fixed parenthesis around FIFO count check

2017-01-21T14:16:20+00:00

FIFO was being read every sample after the "almost full" state was
reached. This was due to an incorrect placement of the parenthesis
in the while condition check.

Note - the fixes tag is not actually correct, but the fix in this patch
would also be needed for it to function correctly so we'll go with that
one.  Backports should pick up both.

Signed-off-by: Matt Ranostay 
Fixes: b74fccad7 ("iio: health: max30100: correct FIFO check condition")
Cc: Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron

iio: health: afe4404: retrieve a valid iio_dev in suspend/resume

2017-01-21T13:12:41+00:00

The suspend/resume functions were using dev_to_iio_dev() to get
the iio_dev. That only works on IIO dev's.  Replace it with i2c
functions to get the correct iio_dev.

Signed-off-by: Alison Schofield 
Acked-by: Andrew F. Davis 
Cc: 
Signed-off-by: Jonathan Cameron

iio: health: afe4403: retrieve a valid iio_dev in suspend/resume

2017-01-21T13:11:06+00:00

The suspend/resume functions were using dev_to_iio_dev() to get
the iio_dev. That only works on IIO dev's.  Replace it with spi
functions to get the correct iio_dev.

Signed-off-by: Alison Schofield 
Acked-by: Andrew F. Davis 
Cc: 
Signed-off-by: Jonathan Cameron

Merge tag 'iio-fixes-for-4.10a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

2017-01-02T15:59:44+00:00

Jonathan writes:

First round of IIO fixes for the 4.10 cycle.

* 104-quad-8
  - Fix selecting wrong register when the index control register is desired.
  - Fix an off by one error when addressing the input/output control register.
  - Fix inverted logic on the active high / low control
* bmi160
  - Sleep for worst case rather than best case amount of time after cmd
  execution begins.
* max44000
  - typo fix in illuminance_integration_time_available listing.
* st-sensors
  - Fix channel data passing.  This one took a while to get tested on 24bit
  parts. Definitely one for stable asap as the bug broke quite a few parts.
  - lis3lv02 needs a data alignment bit set and the scaling was wrong.
* ti_am335x
  - depend on HAS_DMA

iio: accel: st_accel: fix LIS3LV02 reading and scaling

2016-12-31T14:35:04+00:00

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 
Cc: Giuseppe Barba 
Cc: Denis Ciocca 
Signed-off-by: Linus Walleij 
Signed-off-by: Jonathan Cameron

iio: common: st_sensors: fix channel data parsing

2016-12-31T14:32:09+00:00

Using realbits as i2c/spi read len, when that value is not byte aligned
(e.g 12 bits), lead to skip msb part of out data registers.
Fix this taking into account scan_type.shift in addition to
scan_type.realbits as read length:

read_len = DIV_ROUND_UP(realbits + shift, 8)

This fix has been tested on 8, 12, 16, 24 bit sensors

Fixes: e7385de5291e ("iio:st_sensors: align on storagebits boundaries")
Signed-off-by: Lorenzo Bianconi 
Tested-by: Linus Walleij 
Cc: 
Signed-off-by: Jonathan Cameron

iio: max44000: correct value in illuminance_integration_time_available

2016-12-30T20:20:23+00:00

According to the datasheet, the shortest available integration time for
ALS ADC conversion is 1.5625ms but illuminance_integration_time_available
sysfs file shows wrong value.

Cc: Crestez Dan Leonard 
Cc: Jonathan Cameron 
Cc: Hartmut Knaack 
Cc: Lars-Peter Clausen 
Cc: Peter Meerwald-Stadler 
Signed-off-by: Akinobu Mita 
Fixes: d5d8f49b6 ("max44000: Expose ambient sensor scaling")
Cc: 
Signed-off-by: Jonathan Cameron

iio: adc: TI_AM335X_ADC should depend on HAS_DMA

2016-12-30T16:37:48+00:00

If NO_DMA=y:

    ERROR: "bad_dma_ops" [drivers/iio/adc/ti_am335x_adc.ko] undefined!

Add a dependency on HAS_DMA to fix this.

Signed-off-by: Geert Uytterhoeven 
Fixes: f438b9da (" drivers: iio: ti_am335x_adc: add dma support")
Cc: 
Signed-off-by: Jonathan Cameron