linux.git/drivers/iio/humidity, branch v4.9.332

iio: humidity: am2315: Fix buffer alignment in iio_push_to_buffers_with_timestamp()

2021-07-20T14:21:04+00:00

[ Upstream commit f4ca2e2595d9fee65d5ce0d218b22ce00e5b2915 ]

To make code more readable, use a structure to express the channel
layout and ensure the timestamp is 8 byte aligned.

Found during an audit of all calls of uses of
iio_push_to_buffers_with_timestamp()

Fixes: 0d96d5ead3f7 ("iio: humidity: Add triggered buffer support for AM2315")
Signed-off-by: Jonathan Cameron 
Reviewed-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20210501170121.512209-12-jic23@kernel.org
Signed-off-by: Sasha Levin

iio: humidity: hdc100x: fix IIO_HUMIDITYRELATIVE channel reporting

2019-12-21T09:41:52+00:00

commit 342a6928bd5017edbdae376042d8ad6af3d3b943 upstream.

The IIO_HUMIDITYRELATIVE channel was being incorrectly reported back
as percent when it should have been milli percent. This is via an
incorrect scale value being returned to userspace.

Signed-off-by: Chris Lesiak 
Acked-by: Matt Ranostay 
Cc: 
Signed-off-by: Jonathan Cameron 
Signed-off-by: Greg Kroah-Hartman

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

2017-02-09T07:08:30+00:00

commit 5c113b5e0082e90d2e1c7b12e96a7b8cf0623e27 upstream.

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%

Signed-off-by: John Brooks 
Reviewed-by: Harald Geyer 
Signed-off-by: Jonathan Cameron 
Signed-off-by: Greg Kroah-Hartman

Merge 4.8-rc5 into staging-next

2016-09-05T06:13:24+00:00

We want the staging fixes in here as well to handle merge issues.

Signed-off-by: Greg Kroah-Hartman

iio: humidity: hdc100x: add HDC1000 and HDC1008 to Kconfig

2016-08-15T16:10:56+00:00

hdc100x supports Texas Instruments HDC1000 and HDC1008 relative
humidity and temperature sensors. Add these product names to
Kconfig.

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

iio: humidity: hdc100x: fix sensor data reads of temp and humidity

2016-08-15T16:01:53+00:00

Replace the i2c_smbus_read_byte commmands used to retrieve the sensor
data with an i2c_master_recv command.

The smbus read byte method fails because the device does not expect a
stop condition after sending the first byte. When we issue the second
read, we are getting the first byte again. Net effect is that of the 14
bits used for the measurement, the 8 most significant bits are correct,
the lower 6 are not.

None of the smbus read protocols follow the pattern this device requires
(S Addr Rd [A] Data [A] Data NA P), hence the switch to an i2c receive
transaction.

Applicable from original introduction of this driver, but will require
backporting due to churn in the code.

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

iio: add Kconfig selects needed for triggered buffer compiles

2016-08-15T14:42:04+00:00

Select IIO_BUFFER and IIO_TRIGGERED_BUFFER to compile.
Remove IIO_TRIGGER if present since IIO_BUFFER selects it.

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

iio: humidity: am2315: set up buffer timestamps for non-zero values

2016-08-15T14:39:23+00:00

Use the iio_pollfunc_store_time parameter during triggered buffer
set-up to get valid timestamps.

Signed-off-by: Alison Schofield 
Cc: Daniel Baluta 
Reviewed-By: Tiberiu Breana 
Cc: 
Signed-off-by: Jonathan Cameron

Merge 4.7-rc4 into staging-next

2016-06-20T15:25:44+00:00

We want the fixes in here, and we can resolve a merge issue in
drivers/iio/industrialio-trigger.c

Signed-off-by: Greg Kroah-Hartman

iio: hudmidity: hdc100x: fix incorrect shifting and scaling

2016-06-03T12:25:33+00:00

Shifting sensor data to the right 2 bits was incorrect and caused the
scaling values + offsets to be invalid.

Reported-by: Alison Schofield 
Signed-off-by: Matt Ranostay 
Tested-by: Alison Schofield 
Cc: 
Signed-off-by: Jonathan Cameron