<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/iio, branch v4.19.321</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>iio: chemical: bme680: Fix sensor data read operation</title>
<updated>2024-07-05T07:00:33+00:00</updated>
<author>
<name>Vasileios Amoiridis</name>
<email>vassilisamir@gmail.com</email>
</author>
<published>2024-06-06T21:22:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2e2ee64a367e97d433d1f9f735efb69f2612472b'/>
<id>2e2ee64a367e97d433d1f9f735efb69f2612472b</id>
<content type='text'>
commit 4241665e6ea063a9c1d734de790121a71db763fc upstream.

A read operation is happening as follows:

a) Set sensor to forced mode
b) Sensor measures values and update data registers and sleeps again
c) Read data registers

In the current implementation the read operation happens immediately
after the sensor is set to forced mode so the sensor does not have
the time to update properly the registers. This leads to the following
2 problems:

1) The first ever value which is read by the register is always wrong
2) Every read operation, puts the register into forced mode and reads
the data that were calculated in the previous conversion.

This behaviour was tested in 2 ways:

1) The internal meas_status_0 register was read before and after every
read operation in order to verify that the data were ready even before
the register was set to forced mode and also to check that after the
forced mode was set the new data were not yet ready.

2) Physically changing the temperature and measuring the temperature

This commit adds the waiting time in between the set of the forced mode
and the read of the data. The function is taken from the Bosch BME68x
Sensor API [1].

[1]: https://github.com/boschsensortec/BME68x_SensorAPI/blob/v4.4.8/bme68x.c#L490

Fixes: 1b3bd8592780 ("iio: chemical: Add support for Bosch BME680 sensor")
Signed-off-by: Vasileios Amoiridis &lt;vassilisamir@gmail.com&gt;
Link: https://lore.kernel.org/r/20240606212313.207550-5-vassilisamir@gmail.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 4241665e6ea063a9c1d734de790121a71db763fc upstream.

A read operation is happening as follows:

a) Set sensor to forced mode
b) Sensor measures values and update data registers and sleeps again
c) Read data registers

In the current implementation the read operation happens immediately
after the sensor is set to forced mode so the sensor does not have
the time to update properly the registers. This leads to the following
2 problems:

1) The first ever value which is read by the register is always wrong
2) Every read operation, puts the register into forced mode and reads
the data that were calculated in the previous conversion.

This behaviour was tested in 2 ways:

1) The internal meas_status_0 register was read before and after every
read operation in order to verify that the data were ready even before
the register was set to forced mode and also to check that after the
forced mode was set the new data were not yet ready.

2) Physically changing the temperature and measuring the temperature

This commit adds the waiting time in between the set of the forced mode
and the read of the data. The function is taken from the Bosch BME68x
Sensor API [1].

[1]: https://github.com/boschsensortec/BME68x_SensorAPI/blob/v4.4.8/bme68x.c#L490

Fixes: 1b3bd8592780 ("iio: chemical: Add support for Bosch BME680 sensor")
Signed-off-by: Vasileios Amoiridis &lt;vassilisamir@gmail.com&gt;
Link: https://lore.kernel.org/r/20240606212313.207550-5-vassilisamir@gmail.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iio: chemical: bme680: Fix overflows in compensate() functions</title>
<updated>2024-07-05T07:00:33+00:00</updated>
<author>
<name>Vasileios Amoiridis</name>
<email>vassilisamir@gmail.com</email>
</author>
<published>2024-06-06T21:22:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6fa31bbe2ea8665ee970258eb8320cbf231dbe9e'/>
<id>6fa31bbe2ea8665ee970258eb8320cbf231dbe9e</id>
<content type='text'>
commit fdd478c3ae98c3f13628e110dce9b6cfb0d9b3c8 upstream.

There are cases in the compensate functions of the driver that
there could be overflows of variables due to bit shifting ops.
These implications were initially discussed here [1] and they
were mentioned in log message of Commit 1b3bd8592780 ("iio:
chemical: Add support for Bosch BME680 sensor").

[1]: https://lore.kernel.org/linux-iio/20180728114028.3c1bbe81@archlinux/

Fixes: 1b3bd8592780 ("iio: chemical: Add support for Bosch BME680 sensor")
Signed-off-by: Vasileios Amoiridis &lt;vassilisamir@gmail.com&gt;
Link: https://lore.kernel.org/r/20240606212313.207550-4-vassilisamir@gmail.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit fdd478c3ae98c3f13628e110dce9b6cfb0d9b3c8 upstream.

There are cases in the compensate functions of the driver that
there could be overflows of variables due to bit shifting ops.
These implications were initially discussed here [1] and they
were mentioned in log message of Commit 1b3bd8592780 ("iio:
chemical: Add support for Bosch BME680 sensor").

[1]: https://lore.kernel.org/linux-iio/20180728114028.3c1bbe81@archlinux/

Fixes: 1b3bd8592780 ("iio: chemical: Add support for Bosch BME680 sensor")
Signed-off-by: Vasileios Amoiridis &lt;vassilisamir@gmail.com&gt;
Link: https://lore.kernel.org/r/20240606212313.207550-4-vassilisamir@gmail.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iio: chemical: bme680: Fix calibration data variable</title>
<updated>2024-07-05T07:00:33+00:00</updated>
<author>
<name>Vasileios Amoiridis</name>
<email>vassilisamir@gmail.com</email>
</author>
<published>2024-06-06T21:22:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d17f26afde5039c30297e9c6ffc273689e595154'/>
<id>d17f26afde5039c30297e9c6ffc273689e595154</id>
<content type='text'>
commit b47c0fee73a810c4503c4a94ea34858a1d865bba upstream.

According to the BME68x Sensor API [1], the h6 calibration
data variable should be an unsigned integer of size 8.

[1]: https://github.com/boschsensortec/BME68x_SensorAPI/blob/v4.4.8/bme68x_defs.h#L789

Fixes: 1b3bd8592780 ("iio: chemical: Add support for Bosch BME680 sensor")
Signed-off-by: Vasileios Amoiridis &lt;vassilisamir@gmail.com&gt;
Link: https://lore.kernel.org/r/20240606212313.207550-3-vassilisamir@gmail.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b47c0fee73a810c4503c4a94ea34858a1d865bba upstream.

According to the BME68x Sensor API [1], the h6 calibration
data variable should be an unsigned integer of size 8.

[1]: https://github.com/boschsensortec/BME68x_SensorAPI/blob/v4.4.8/bme68x_defs.h#L789

Fixes: 1b3bd8592780 ("iio: chemical: Add support for Bosch BME680 sensor")
Signed-off-by: Vasileios Amoiridis &lt;vassilisamir@gmail.com&gt;
Link: https://lore.kernel.org/r/20240606212313.207550-3-vassilisamir@gmail.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iio: chemical: bme680: Fix pressure value output</title>
<updated>2024-07-05T07:00:33+00:00</updated>
<author>
<name>Vasileios Amoiridis</name>
<email>vassilisamir@gmail.com</email>
</author>
<published>2024-06-06T21:22:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=272736d778a42a3cdb623d53665a0e6a85125b66'/>
<id>272736d778a42a3cdb623d53665a0e6a85125b66</id>
<content type='text'>
commit ae1f7b93b52095be6776d0f34957b4f35dda44d9 upstream.

The IIO standard units are measured in kPa while the driver
is using hPa.

Apart from checking the userspace value itself, it is mentioned also
in the Bosch API [1] that the pressure value is in Pascal.

[1]: https://github.com/boschsensortec/BME68x_SensorAPI/blob/v4.4.8/bme68x_defs.h#L742

Fixes: 1b3bd8592780 ("iio: chemical: Add support for Bosch BME680 sensor")
Signed-off-by: Vasileios Amoiridis &lt;vassilisamir@gmail.com&gt;
Link: https://lore.kernel.org/r/20240606212313.207550-2-vassilisamir@gmail.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit ae1f7b93b52095be6776d0f34957b4f35dda44d9 upstream.

The IIO standard units are measured in kPa while the driver
is using hPa.

Apart from checking the userspace value itself, it is mentioned also
in the Bosch API [1] that the pressure value is in Pascal.

[1]: https://github.com/boschsensortec/BME68x_SensorAPI/blob/v4.4.8/bme68x_defs.h#L742

Fixes: 1b3bd8592780 ("iio: chemical: Add support for Bosch BME680 sensor")
Signed-off-by: Vasileios Amoiridis &lt;vassilisamir@gmail.com&gt;
Link: https://lore.kernel.org/r/20240606212313.207550-2-vassilisamir@gmail.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iio: adc: ad7266: Fix variable checking bug</title>
<updated>2024-07-05T07:00:33+00:00</updated>
<author>
<name>Fernando Yang</name>
<email>hagisf@usp.br</email>
</author>
<published>2024-06-03T18:07:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=75a024d3ab0d331fc1d0b640b00e63d31d556b1e'/>
<id>75a024d3ab0d331fc1d0b640b00e63d31d556b1e</id>
<content type='text'>
commit a2b86132955268b2a1703082fbc2d4832fc001b8 upstream.

The ret variable was not checked after iio_device_release_direct_mode(),
which could possibly cause errors

Fixes: c70df20e3159 ("iio: adc: ad7266: claim direct mode during sensor read")
Signed-off-by: Fernando Yang &lt;hagisf@usp.br&gt;
Link: https://lore.kernel.org/r/20240603180757.8560-1-hagisf@usp.br
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a2b86132955268b2a1703082fbc2d4832fc001b8 upstream.

The ret variable was not checked after iio_device_release_direct_mode(),
which could possibly cause errors

Fixes: c70df20e3159 ("iio: adc: ad7266: claim direct mode during sensor read")
Signed-off-by: Fernando Yang &lt;hagisf@usp.br&gt;
Link: https://lore.kernel.org/r/20240603180757.8560-1-hagisf@usp.br
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iio: dac: ad5592r: fix temperature channel scaling value</title>
<updated>2024-07-05T07:00:30+00:00</updated>
<author>
<name>Marc Ferland</name>
<email>marc.ferland@sonatest.com</email>
</author>
<published>2024-05-01T15:05:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9eaaefbae8f5ddbed0fce822042ad969f5f876c5'/>
<id>9eaaefbae8f5ddbed0fce822042ad969f5f876c5</id>
<content type='text'>
[ Upstream commit 279428df888319bf68f2686934897301a250bb84 ]

The scale value for the temperature channel is (assuming Vref=2.5 and
the datasheet):

    376.7897513

When calculating both val and val2 for the temperature scale we
use (3767897513/25) and multiply it by Vref (here I assume 2500mV) to
obtain:

  2500 * (3767897513/25) ==&gt; 376789751300

Finally we divide with remainder by 10^9 to get:

    val = 376
    val2 = 789751300

However, we return IIO_VAL_INT_PLUS_MICRO (should have been NANO) as
the scale type. So when converting the raw temperature value to the
'processed' temperature value we will get (assuming raw=810,
offset=-753):

    processed = (raw + offset) * scale_val
              = (810 + -753) * 376
	      = 21432

    processed += div((raw + offset) * scale_val2, 10^6)
              += div((810 + -753) * 789751300, 10^6)
	      += 45015
    ==&gt; 66447
    ==&gt; 66.4 Celcius

instead of the expected 21.5 Celsius.

Fix this issue by changing IIO_VAL_INT_PLUS_MICRO to
IIO_VAL_INT_PLUS_NANO.

Fixes: 56ca9db862bf ("iio: dac: Add support for the AD5592R/AD5593R ADCs/DACs")
Signed-off-by: Marc Ferland &lt;marc.ferland@sonatest.com&gt;
Link: https://lore.kernel.org/r/20240501150554.1871390-1-marc.ferland@sonatest.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 279428df888319bf68f2686934897301a250bb84 ]

The scale value for the temperature channel is (assuming Vref=2.5 and
the datasheet):

    376.7897513

When calculating both val and val2 for the temperature scale we
use (3767897513/25) and multiply it by Vref (here I assume 2500mV) to
obtain:

  2500 * (3767897513/25) ==&gt; 376789751300

Finally we divide with remainder by 10^9 to get:

    val = 376
    val2 = 789751300

However, we return IIO_VAL_INT_PLUS_MICRO (should have been NANO) as
the scale type. So when converting the raw temperature value to the
'processed' temperature value we will get (assuming raw=810,
offset=-753):

    processed = (raw + offset) * scale_val
              = (810 + -753) * 376
	      = 21432

    processed += div((raw + offset) * scale_val2, 10^6)
              += div((810 + -753) * 789751300, 10^6)
	      += 45015
    ==&gt; 66447
    ==&gt; 66.4 Celcius

instead of the expected 21.5 Celsius.

Fix this issue by changing IIO_VAL_INT_PLUS_MICRO to
IIO_VAL_INT_PLUS_NANO.

Fixes: 56ca9db862bf ("iio: dac: Add support for the AD5592R/AD5593R ADCs/DACs")
Signed-off-by: Marc Ferland &lt;marc.ferland@sonatest.com&gt;
Link: https://lore.kernel.org/r/20240501150554.1871390-1-marc.ferland@sonatest.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iio: dac: ad5592r: un-indent code-block for scale read</title>
<updated>2024-07-05T07:00:30+00:00</updated>
<author>
<name>Alexandru Ardelean</name>
<email>alexandru.ardelean@analog.com</email>
</author>
<published>2020-07-06T11:02:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c101996c9dabd9d809c12f686547b7035c087f10'/>
<id>c101996c9dabd9d809c12f686547b7035c087f10</id>
<content type='text'>
[ Upstream commit b004fe33034cc64f72c20923be71cf1e6c9a624c ]

The next rework may require an unindentation of a code block in
ad5592r_read_raw(), which would make review a bit more difficult.

This change unindents the code block for reading the scale of the
non-temperature channels.

Signed-off-by: Alexandru Ardelean &lt;alexandru.ardelean@analog.com&gt;
Link: https://lore.kernel.org/r/20200706110259.23947-2-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Stable-dep-of: 279428df8883 ("iio: dac: ad5592r: fix temperature channel scaling value")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b004fe33034cc64f72c20923be71cf1e6c9a624c ]

The next rework may require an unindentation of a code block in
ad5592r_read_raw(), which would make review a bit more difficult.

This change unindents the code block for reading the scale of the
non-temperature channels.

Signed-off-by: Alexandru Ardelean &lt;alexandru.ardelean@analog.com&gt;
Link: https://lore.kernel.org/r/20200706110259.23947-2-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Stable-dep-of: 279428df8883 ("iio: dac: ad5592r: fix temperature channel scaling value")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iio: dac: ad5592r-base: Replace indio_dev-&gt;mlock with own device lock</title>
<updated>2024-07-05T07:00:30+00:00</updated>
<author>
<name>Sergiu Cuciurean</name>
<email>sergiu.cuciurean@analog.com</email>
</author>
<published>2020-05-20T12:02:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b576d7d08f26d40789313ec6a8acc966a149c37f'/>
<id>b576d7d08f26d40789313ec6a8acc966a149c37f</id>
<content type='text'>
[ Upstream commit 33c53cbf8f7bc8d62f6146a19da97c8594376ff0 ]

As part of the general cleanup of indio_dev-&gt;mlock, this change replaces
it with a local lock on the device's state structure.
This also removes unused iio_dev pointers.

Signed-off-by: Sergiu Cuciurean &lt;sergiu.cuciurean@analog.com&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Stable-dep-of: 279428df8883 ("iio: dac: ad5592r: fix temperature channel scaling value")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 33c53cbf8f7bc8d62f6146a19da97c8594376ff0 ]

As part of the general cleanup of indio_dev-&gt;mlock, this change replaces
it with a local lock on the device's state structure.
This also removes unused iio_dev pointers.

Signed-off-by: Sergiu Cuciurean &lt;sergiu.cuciurean@analog.com&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Stable-dep-of: 279428df8883 ("iio: dac: ad5592r: fix temperature channel scaling value")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iio: common: ms_sensors: ms_sensors_i2c: fix humidity conversion time table</title>
<updated>2024-01-08T10:27:35+00:00</updated>
<author>
<name>Javier Carrasco</name>
<email>javier.carrasco.cruz@gmail.com</email>
</author>
<published>2023-10-26T15:44:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0892d2c96545e6ac21f5853b43d55d8767863cbf'/>
<id>0892d2c96545e6ac21f5853b43d55d8767863cbf</id>
<content type='text'>
commit 54cf39ec16335dadbe1ba008d8e5e98dae3e26f8 upstream.

The HTU21 offers 4 sampling frequencies: 20, 40, 70 and 120, which are
associated to an index that is used to select the right measurement
resolution and its corresponding measurement time. The current
implementation selects the measurement resolution and the temperature
measurement time properly, but it does not select the right humidity
measurement time in all cases.

In summary, the 40 and 70 humidity measurement times are swapped.

The reason for that is probably the unusual coding for the measurement
resolution. According to the datasheet, the bits [7,0] of the "user
register" are used as follows to select the bit resolution:

--------------------------------------------------
| Bit 7 | Bit 0 | RH | Temp | Trh (us) | Tt (us) |
--------------------------------------------------
|   0   |   0   | 12 |  14  |  16000   |  50000  |
--------------------------------------------------
|   0   |   1   | 8  |  12  |  3000    |  13000  |
--------------------------------------------------
|   1   |   0   | 10 |  13  |  5000    |  25000  |
--------------------------------------------------
|   1   |   1   | 11 |  11  |  8000    |  7000   |
--------------------------------------------------
*This table is available in the official datasheet, page 13/21. I have
just appended the times provided in the humidity/temperature tables,
pages 3/21, 5/21. Note that always a pair of resolutions is selected.

The sampling frequencies [20, 40, 70, 120] are assigned to a linear
index [0..3] which is then coded as follows [1]:

Index    [7,0]
--------------
idx 0     0,0
idx 1     1,0
idx 2     0,1
idx 3     1,1

That is done that way because the temperature measurements are being
used as the reference for the sampling frequency (the frequencies and
the temperature measurement times are correlated), so increasing the
index always reduces the temperature measurement time and its
resolution. Therefore, the temperature measurement time array is as
simple as [50000, 25000, 13000, 7000]

On the other hand, the humidity resolution cannot follow the same
pattern because of the way it is coded in the "user register", where
both resolutions are selected at the same time. The humidity measurement
time array is the following: [16000, 3000, 5000, 8000], which defines
the following assignments:

Index    [7,0]    Trh
-----------------------
idx 0     0,0     16000  -&gt; right, [0,0] selects 12 bits (Trh = 16000)
idx 1     1,0     3000   -&gt; wrong! [1,0] selects 10 bits (Trh = 5000)
idx 2     0,1     5000   -&gt; wrong! [0,1] selects 8 bits (Trh = 3000)
idx 3     1,1     8000   -&gt; right, [1,1] selects 11 bits (Trh = 8000)

The times have been ordered as if idx = 1 -&gt; [0,1] and idx = 2 -&gt; [1,0],
which is not the case for the reason explained above.

So a simple modification is required to obtain the right humidity
measurement time array, swapping the values in the positions 1 and 2.

The right table should be the following: [16000, 5000, 3000, 8000]

Fix the humidity measurement time array with the right idex/value
coding.

[1] The actual code that makes this coding and assigns it to the current
value of the "user register" is the following:
config_reg &amp;= 0x7E;
config_reg |= ((i &amp; 1) &lt;&lt; 7) + ((i &amp; 2) &gt;&gt; 1);

Fixes: d574a87cc311 ("Add meas-spec sensors common part")
Signed-off-by: Javier Carrasco &lt;javier.carrasco.cruz@gmail.com&gt;
Link: https://lore.kernel.org/r/20231026-topic-htu21_conversion_time-v1-1-bd257dc44209@gmail.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 54cf39ec16335dadbe1ba008d8e5e98dae3e26f8 upstream.

The HTU21 offers 4 sampling frequencies: 20, 40, 70 and 120, which are
associated to an index that is used to select the right measurement
resolution and its corresponding measurement time. The current
implementation selects the measurement resolution and the temperature
measurement time properly, but it does not select the right humidity
measurement time in all cases.

In summary, the 40 and 70 humidity measurement times are swapped.

The reason for that is probably the unusual coding for the measurement
resolution. According to the datasheet, the bits [7,0] of the "user
register" are used as follows to select the bit resolution:

--------------------------------------------------
| Bit 7 | Bit 0 | RH | Temp | Trh (us) | Tt (us) |
--------------------------------------------------
|   0   |   0   | 12 |  14  |  16000   |  50000  |
--------------------------------------------------
|   0   |   1   | 8  |  12  |  3000    |  13000  |
--------------------------------------------------
|   1   |   0   | 10 |  13  |  5000    |  25000  |
--------------------------------------------------
|   1   |   1   | 11 |  11  |  8000    |  7000   |
--------------------------------------------------
*This table is available in the official datasheet, page 13/21. I have
just appended the times provided in the humidity/temperature tables,
pages 3/21, 5/21. Note that always a pair of resolutions is selected.

The sampling frequencies [20, 40, 70, 120] are assigned to a linear
index [0..3] which is then coded as follows [1]:

Index    [7,0]
--------------
idx 0     0,0
idx 1     1,0
idx 2     0,1
idx 3     1,1

That is done that way because the temperature measurements are being
used as the reference for the sampling frequency (the frequencies and
the temperature measurement times are correlated), so increasing the
index always reduces the temperature measurement time and its
resolution. Therefore, the temperature measurement time array is as
simple as [50000, 25000, 13000, 7000]

On the other hand, the humidity resolution cannot follow the same
pattern because of the way it is coded in the "user register", where
both resolutions are selected at the same time. The humidity measurement
time array is the following: [16000, 3000, 5000, 8000], which defines
the following assignments:

Index    [7,0]    Trh
-----------------------
idx 0     0,0     16000  -&gt; right, [0,0] selects 12 bits (Trh = 16000)
idx 1     1,0     3000   -&gt; wrong! [1,0] selects 10 bits (Trh = 5000)
idx 2     0,1     5000   -&gt; wrong! [0,1] selects 8 bits (Trh = 3000)
idx 3     1,1     8000   -&gt; right, [1,1] selects 11 bits (Trh = 8000)

The times have been ordered as if idx = 1 -&gt; [0,1] and idx = 2 -&gt; [1,0],
which is not the case for the reason explained above.

So a simple modification is required to obtain the right humidity
measurement time array, swapping the values in the positions 1 and 2.

The right table should be the following: [16000, 5000, 3000, 8000]

Fix the humidity measurement time array with the right idex/value
coding.

[1] The actual code that makes this coding and assigns it to the current
value of the "user register" is the following:
config_reg &amp;= 0x7E;
config_reg |= ((i &amp; 1) &lt;&lt; 7) + ((i &amp; 2) &gt;&gt; 1);

Fixes: d574a87cc311 ("Add meas-spec sensors common part")
Signed-off-by: Javier Carrasco &lt;javier.carrasco.cruz@gmail.com&gt;
Link: https://lore.kernel.org/r/20231026-topic-htu21_conversion_time-v1-1-bd257dc44209@gmail.com
Cc: &lt;Stable@vger.kernel.org&gt;
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iio: imu: inv_mpu6050: fix an error code problem in inv_mpu6050_read_raw</title>
<updated>2024-01-08T10:27:35+00:00</updated>
<author>
<name>Su Hui</name>
<email>suhui@nfschina.com</email>
</author>
<published>2023-10-30T02:02:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5212dfdef180209c4c819aaaff7f1c0eab072248'/>
<id>5212dfdef180209c4c819aaaff7f1c0eab072248</id>
<content type='text'>
[ Upstream commit c3df0e29fb7788c4b3ddf37d5ed87dda2b822943 ]

inv_mpu6050_sensor_show() can return -EINVAL or IIO_VAL_INT. Return the
true value rather than only return IIO_VAL_INT.

Fixes: d5098447147c ("iio: imu: mpu6050: add calibration offset support")
Signed-off-by: Su Hui &lt;suhui@nfschina.com&gt;
Link: https://lore.kernel.org/r/20231030020218.65728-1-suhui@nfschina.com
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c3df0e29fb7788c4b3ddf37d5ed87dda2b822943 ]

inv_mpu6050_sensor_show() can return -EINVAL or IIO_VAL_INT. Return the
true value rather than only return IIO_VAL_INT.

Fixes: d5098447147c ("iio: imu: mpu6050: add calibration offset support")
Signed-off-by: Su Hui &lt;suhui@nfschina.com&gt;
Link: https://lore.kernel.org/r/20231030020218.65728-1-suhui@nfschina.com
Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
