buffer.h supplies everything needed for devices using buffers.
buffer_impl.h supplies access to the internals as needed to write
a buffer implementation.
This was really motivated by the mess that turned up in the
kernel-doc documentation pulled in by the new sphinx docs.
It made it clear that our logical separations in headers were
generally terrible. The buffer case was easy to sort out without
greatly effecting drivers so here it is.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
It's bad practice and only done in this fake driver + it breaks my
attempt to take struct buffer opaque. Not worth an access function
as it shouldn't be done anyway.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
This is a precursor to the splitting of buffer.h into parts relevant
to buffer implementation vs those for devices using buffers.
struct buffer is about to become opaque as far as the header is
concerned.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
These were only getting access to the internals of struct iio_dev via
the include of iio.h within buffer.h. This should always have been
explicitly included by the buffer implementations themselves.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
As a precursor to splitting buffer.h, lets make sure all drivers
include the relevant headers rather than relying on picking them
up from kfifo_buf.h.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Ancient legacy of me doing it wrong which it is nice to clear
up whilst we are here.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
This is a necessary step in taking the buffer implementation
opaque.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Nothing outside of indiustrialio-buffer.c should be using this.
Requires a large amount of juggling of functions to avoid a
forward definition.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
The earlier deployed LIS3LV02DL driver had already defined a few
DT bindings that need to be supported by the new more generic
driver and listed as compatible but deprecated bindings in the
documentation.
After this we can start to activate the new driver with the old
systems where applicable.
As part of this enablement: make us depend on the old drivers
not being in use so we don't get a kernel with two competing
drivers.
Cc: devicetree@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Gravity sensor is a soft sensor, which derives value from
standard accelerometer device by filtering out the acceleration
which is not caused by gravity.
Gravity sensor provides a three dimensional vector indicating
the direction and magnitude of gravity. Typically, this sensor
is used to determine the device's relative orientation in space.
The units and the coordinate system is the same as the one used by
the acceleration sensor.
When a device is at rest, the output of the gravity sensor should
be identical to that of the accelerometer.
More information can be found in:
http://www.usb.org/developers/hidpage/HUTRR59_-_Usages_for_Wearables.pdf
Gravity sensor and accelerometer have similar channels and
share channel usage ids. So the most of the code for accel_3d
can be reused.
Signed-off-by: Song Hongyan <hongyan.song@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add new channel types support for gravity sensor.
Gravity sensor provides an application-level or physical collection that
identifies a device that measures exclusively the force of Earth's
gravity along any number of axes.
More information can be found in:
http://www.usb.org/developers/hidpage/HUTRR59_-_Usages_for_Wearables.pdf
Signed-off-by: Song Hongyan <hongyan.song@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This patch adds the ACPI/PNP ID. The AD5592/3 driver core is already
designed around the unified device property API.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This patch adds the ACPI/PNP ID. The AD5592/3 driver core is already
designed around the unified device property API.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This adds a driver for the Capella Microsystems CM3605 Ambient
Light Sensor and proximity sensor. This is a pretty simple entirely
analog device that is interfaced with the target system using
the POUT (proximity out) and AOUT (ambient light out) signals.
The POUT signal is a simple high/low signal that indicates whether
an object is in proximity, most typically used to detect a face
in front of a mobile device. The signal requires that an infrared
LED is mounted next to the device, making IR light reflect off
the object in proximity and triggering the POUT signal. We grab
a GPIO pin to handle the POUT signal as an interrupt line and
register this as an event channel for the sensor.
Since the proximity sensor requires an IR LED, we add a LED trigger
named "cm3605" so that the infrared LED can just associate with
this trigger to be sure it is always on when the proximity sensor
needs it.
The AOUT is an analog voltage between 0 and 1550 mV that indicate
the LUX value in the ambient light: this is orthogonal to the
proximity sensor functionality. Since this analog voltage needs
to be converted into a digital value, the driver grabs an IIO
channel named "aout" associated with the device.
This patch created a combined ALS and proximity sensor driver.
The former supports raw reads of the LUX value and the latter
will generate proximity events.
To integrate this properly with Linux we also add a supply
regulator for the VDD pin (driving both functions) and add device
tree bindings to define the RSET resistor that in turn configures
the luminosity range of the ALS sensor.
Since the sensor needs to be on more or less constantly, we
restrict the power management to system suspend/resume: we
disable the IR LED and disable the regulator for VDD on suspend
and take them back up on resume.
Tests:
cd /sys/bus/iio/devices/iio:device1
cat in_illuminance_raw
304
(hold hand over sensor)
cat in_illuminance_raw
17
iio_event_monitor cm3605
Found IIO device with name cm3605 with device number 1
(hold hand over sensor)
Event: time: 2444842301447, type: proximity, channel: 0,
evtype: thresh, direction: falling
(remove hand over sensor)
Event: time: 2445583440706, type: proximity, channel: 0,
evtype: thresh, direction: rising
Cc: Capella Microsystems <capellamicro@gmail.com>
Cc: Kevin Tsai <ktsai@capellamicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
There is one light sensor type defined in the sensor hub specification,
which has one Illuminance field. It doesn't distinguish between ambient
light sensor or color sensor. Currently it is presented as IIO_INTENSITY
channel. There are some user spaces specifically looking for IIO_LIGHT
channel.
To satisfy such user spaces this change also add a duplicate IIO_LIGHT
channel. The units of measurement of Illuminance field is Lux, so it is
still compatible to IIO ABI.
Signed-off-by: Kweh, Hock Leong <hock.leong.kweh@intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Both devices are using the same iio_chan_spec to define which settings
are exported with sysfs. Both are properly configured to set/get
sampling frequency for pressure and temperature. They also properly
export available sampling frequencies. The only missing thing is
sampling_frequency sysfs file, which allows to set/get this property
from userspace.
Add sampling frequency to iio channel info mask, so sampling_frequency
file is properly exported using sysfs.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Datasheet of each device (lps331ap, lps25h, lps001wp, lps22hb) says that
the pressure and temperature data is a 2's complement.
I'm sending this the slow way, as negative pressures on these are pretty
unusual and the nature of the fixing of multiple device introduction patches
will make it hard to apply to older kernels - Jonathan.
Fixes: 217494e5b7 ("iio:pressure: Add STMicroelectronics pressures driver")
Fixes: 2f5effcbd0 ("iio: pressure-core: st: Expand and rename LPS331AP's channel descriptor")
Fixes: 7885a8ce68 ("iio: pressure: st: Add support for new LPS001WP pressure sensor")
Fixes: e039e2f5b4 ("iio:st_pressure:initial lps22hb sensor support")
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
From now on we can add bmi160 device to device-tree by specifying
compatible string.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
From now on we can add bmi160 device to device-tree by specifying
compatible string.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Several ADC channels are supported in PMIC which can be used to
measure voltage, temperature, current etc. Different scaling can be
applied on the obtained voltage to report in physical units. Scaling
functionality can be different per channel. Add scaling support per
channel. Every channel present in adc has an unique conversion formula
for obtained voltage. Add support to report in Raw as well as in
processed format. Scaling is applied when processed read is requested
and is not applied when a Raw read is requested.
Signed-off-by: Rama Krishna Phani A <rphani@codeaurora.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Several channels are supported in ADC of PMIC which can be used to
measure voltage, temperature, current etc., Hardware provides
readings for all channels in adc code. That adc code needs to be
converted to voltage. Logic for conversion of adc code to voltage
is common for all ADC channels(voltage, temperature, current
.,etc). Implement separate function for generic conversion logic.
Signed-off-by: Rama Krishna Phani A <rphani@codeaurora.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
In function cm3232_reg_init(), it returns 0 even if the last call to
i2c_smbus_write_byte_data() returns a negative value (indicates error).
As a result, the return value may be inconsistent with the execution
status, and the caller of cm3232_reg_init() will not be able to detect
the error. This patch fixes the bug.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=188641
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Added timestamp channel. With this change, each sample has a timestamp.
This timestamp can be from the sensor hub when present or local kernel
timestamp. HID sensors can send timestamp with input data using usage id
HID_USAGE_SENSOR_TIME_TIMESTAMP. This timestamp value is converted to
nano seconds before pushing this sample to the iio core.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This adds a new driver for the TI ADS7950 family of ADC chips. These
communicate using SPI and come in 8/10/12-bit and 4/8/12/16 channel
varieties.
Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
msleep(1~20) may not do what the caller intends, and will often sleep longer.
(~20 ms actual sleep for any value given in the 1~20ms range)
This is not the desired behaviour for many cases like device resume time,
device suspend time, device enable time, data reading time, etc.
Thus, change msleep to usleep_range for precise wakeups.
Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
smatch warned:
sval_binop_signed: invalid divide LLONG_MIN/-1
and this fixes it. It's actually good to have, in order to avoid accidental
checking for negative return values here.
Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Support driver probe by reading unique HID on systems based on ACPI instead
of DT compatible strings.
Signed-off-by: Shrirang Bagul <shrirang.bagul@canonical.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Compatible strings are not available on ACPI based systems. This patch adds
support to use DSDT information read from platform BIOS instead for probing
st pressure sensors.
Signed-off-by: Shrirang Bagul <shrirang.bagul@canonical.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add support to probe st_accel sensors on i2c bus using ACPI. Compatible
strings are not avaialable on ACPI based systems.
Signed-off-by: Shrirang Bagul <shrirang.bagul@canonical.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add support to match st sensors using information passed from ACPI DST
tables.
Signed-off-by: Shrirang Bagul <shrirang.bagul@canonical.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
There are 2 usage types (Magnetic Flux and Heading data field) for HID
compass sensor, thus the values of offset, scale, and sensitivity should
be separated according to their respective usage type. The changes made
are as below:
1. Hysteresis: A struct hid_sensor_common rot_attributes is created in
struct magn_3d_state to contain the sensitivity for IIO_ROT.
2. Scale: scale_pre_decml and scale_post_decml are separated for IIO_MAGN
and IIO_ROT.
3. Offset: Same as scale, value_offset is separated for IIO_MAGN and
IIO_ROT.
For sensitivity, HID_USAGE_SENSOR_ORIENT_MAGN_FLUX and
HID_USAGE_SENSOR_ORIENT_MAGN_HEADING are used for sensivitity fields based
on the HID Sensor Usages specifications. Hence, these changes are added on
the sensitivity field.
Signed-off-by: Ooi, Joyce <joyce.ooi@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This array is supposed to have 10 elements. Smatch complains that with
the current code we can have n == max_ints and read beyond the end of
the array.
Fixes: ac4f6eee8f ("staging: iio: TAOS tsl258x: Device driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
We have #defines for all the individual sensor registers and
value/mask pairs #defined at the top of the file and used at
exactly one spot.
This is usually good if the #defines give a meaning to the
opaque magic numbers.
However in this case, the semantic meaning is inherent in the
name of the C99-addressable fields, and that means duplication
of information, and only makes the code hard to maintain since
you every time have to add a new #define AND update the site
where it is to be used.
Get rid of the #defines and just open code the values into the
appropriate struct elements. Make sure to explicitly address
the .hz and .value fields in the st_sensor_odr_avl struct
so that the meaning of all values is clear.
This patch is purely syntactic should have no semantic effect.
Cc: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This patch adds support for STMicroelectronics STM32 MCU's analog to
digital converter.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add core driver for STMicroelectronics STM32 ADC (Analog to Digital
Converter). STM32 ADC can be composed of up to 3 ADCs with shared
resources like clock prescaler, common interrupt line and analog
reference voltage.
This core driver basically manages shared resources.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Includes Peter Rosin's interesting drivers for a comparator. First complex
use we have had with an analog front end made from discrete components.
Brian Masney's work on moving the tsl2583 driver out of staging also
feature extensively!
New Drivers
* DAC based on a digital potentiometer
- New driver for the use of a dpot as a DAC. Includes bindings and Axentia
entry in vendor prefixes.
* Envelope detector baed on DAC and a comparator including device tree
bindings.
Staging Graduation
* tsl2583.
Core new features
- Core provision for _available attributes. This one had been stalled for
a long time until Peter picked it up and ran with it!
- In kernel interface helpers to retrieve available info from channels.
Driver new features
* mcp4531
- Add range of available raw values (used for the dpot dac driver).
Driver cleanups and fixes for issues introduced
* ad7766
- Testing the wrong variable following devm_regulator_bulk_get introduced
with the driver earlier in this cycle.
* ad9832
- Fix a wrong ordering in the probe introduced in the previous set of
patches. A use before allocation bug.
* cros_ec_sensors
- Testing for an error in a u8 will never work.
* mpu3050
- Remove duplicate initializer for the module owner.
- Add missing i2c dependency.
- Inform the i2c mux core how it is used - step one in implifying device
tree bindings.
* st-sensors
- Get rid of large number of uninformative defines in favour of putting the
constants where they are relevant. It is clear what they are from where
they are used.
* tsl2583
- Fix unused function warning when CONFIG_PM disabled and remove the
ifdefs in favour of __maybe_unused.
- Refactor taos_chip_on to only read relevant registers.
- Make sure calibscale and integration time are being set.
- Verify chip is in ready to be used before calibration.
- Remove some repeated checks for chip status (it's protected by a mutex
so can't change until it's released)
- Change current state storage from a tristate enum to a boolean seeing as
only two values are actually used now.
- Drop a redundant write to the control regiser in taos_probe (it's a noop)
- Drop the FSF mailing address.
- Clean up logging to not use hard coded function names (use __func__
instead).
- Cleanup up variable and function name prefixes.
- Alignment of #define fixes.
- Fix comparison between signed and unsigned integer warnings.
- Add some newlines in favour of readability.
- Combine the two sysfs ABI docs that somehow ended up in different places.
- Fix multiline comment syntax.
- Move a code block to inside an else statement as it makes more sense there.
- Change tsl2583_als_calibrate to return 0 rather than a value nothing
reads.
- Drop some pointless brackets
- Don't assume 32bit unsigned int.
- Change to a per device instance lux table.
- Add missing tsl2583 to the list of supported devices in the intro comments.
- Improve commment on clearing of interrupts.
- Drop some uninformative comments.
- Drop a memset call that doesn't do anything useful any more.
- Don't initialize some return variables that are always set.
- Add Brian Masney as a module author after all these changes.
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Merge tag 'iio-for-4.10c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes:
Third set of IIO new device support, features and cleanup for the 4.10 cycle.
Includes Peter Rosin's interesting drivers for a comparator. First complex
use we have had with an analog front end made from discrete components.
Brian Masney's work on moving the tsl2583 driver out of staging also
feature extensively!
New Drivers
* DAC based on a digital potentiometer
- New driver for the use of a dpot as a DAC. Includes bindings and Axentia
entry in vendor prefixes.
* Envelope detector baed on DAC and a comparator including device tree
bindings.
Staging Graduation
* tsl2583.
Core new features
- Core provision for _available attributes. This one had been stalled for
a long time until Peter picked it up and ran with it!
- In kernel interface helpers to retrieve available info from channels.
Driver new features
* mcp4531
- Add range of available raw values (used for the dpot dac driver).
Driver cleanups and fixes for issues introduced
* ad7766
- Testing the wrong variable following devm_regulator_bulk_get introduced
with the driver earlier in this cycle.
* ad9832
- Fix a wrong ordering in the probe introduced in the previous set of
patches. A use before allocation bug.
* cros_ec_sensors
- Testing for an error in a u8 will never work.
* mpu3050
- Remove duplicate initializer for the module owner.
- Add missing i2c dependency.
- Inform the i2c mux core how it is used - step one in implifying device
tree bindings.
* st-sensors
- Get rid of large number of uninformative defines in favour of putting the
constants where they are relevant. It is clear what they are from where
they are used.
* tsl2583
- Fix unused function warning when CONFIG_PM disabled and remove the
ifdefs in favour of __maybe_unused.
- Refactor taos_chip_on to only read relevant registers.
- Make sure calibscale and integration time are being set.
- Verify chip is in ready to be used before calibration.
- Remove some repeated checks for chip status (it's protected by a mutex
so can't change until it's released)
- Change current state storage from a tristate enum to a boolean seeing as
only two values are actually used now.
- Drop a redundant write to the control regiser in taos_probe (it's a noop)
- Drop the FSF mailing address.
- Clean up logging to not use hard coded function names (use __func__
instead).
- Cleanup up variable and function name prefixes.
- Alignment of #define fixes.
- Fix comparison between signed and unsigned integer warnings.
- Add some newlines in favour of readability.
- Combine the two sysfs ABI docs that somehow ended up in different places.
- Fix multiline comment syntax.
- Move a code block to inside an else statement as it makes more sense there.
- Change tsl2583_als_calibrate to return 0 rather than a value nothing
reads.
- Drop some pointless brackets
- Don't assume 32bit unsigned int.
- Change to a per device instance lux table.
- Add missing tsl2583 to the list of supported devices in the intro comments.
- Improve commment on clearing of interrupts.
- Drop some uninformative comments.
- Drop a memset call that doesn't do anything useful any more.
- Don't initialize some return variables that are always set.
- Add Brian Masney as a module author after all these changes.
Move tsl2580, tsl2581, tsl2583 driver out of staging into mainline.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The DAC is used to find the peak level of an alternating voltage input
signal by a binary search using the output of a comparator wired to
an interrupt pin. Like so:
_
| \
input +------>-------|+ \
| \
.-------. | }---.
| | | / |
| dac|-->--|- / |
| | |_/ |
| | |
| | |
| irq|------<-------'
| |
'-------'
Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
It is assumed that the dpot is used as a voltage divider between the
current dpot wiper setting and the maximum resistance of the dpot. The
divided voltage is provided by a vref regulator.
.------.
.-----------. | |
| vref |--' .---.
| regulator |--. | |
'-----------' | | d |
| | p |
| | o | wiper
| | t |<---------+
| | |
| '---' dac output voltage
| |
'------+------------+
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Example:
$ cat '/sys/bus/iio/devices/iio:device0/out_resistance_raw_available'
[0 1 256]
Meaning: min 0, step 1 and max 256.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Specifically a helper for reading the available maximum raw value of a
channel and a helper for forwarding read_avail requests for raw values
from one iio driver to an iio channel that is consumed.
These rather specific helpers are in turn built with generic helpers
making it easy to build more helpers for available values as needed.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
A large number of attributes can only take a limited range of values.
Currently in IIO this is handled by directly registering additional
*_available attributes thus providing this information to userspace.
It is desirable to provide this information via the core for much the same
reason this was done for the actual channel information attributes in the
first place. If it isn't there, then it can only really be accessed from
userspace. Other in kernel IIO consumers have no access to what valid
parameters are.
Two forms are currently supported:
* list of values in one particular IIO_VAL_* format.
e.g. 1.300000 1.500000 1.730000
* range specification with a step size:
e.g. [1.000000 0.500000 2.500000]
equivalent to 1.000000 1.5000000 2.000000 2.500000
An addition set of masks are used to allow different sharing rules for the
*_available attributes generated.
This allows for example:
in_accel_x_offset
in_accel_y_offset
in_accel_offset_available.
We could have gone with having a specification for each and every
info_mask element but that would have meant changing the existing userspace
ABI. This approach does not.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
[forward ported, added some docs and fixed buffer overflows /peda]
Acked-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
As found by gcc -Wmaybe-uninitialized, having a storage_bytes value other
than 2 or 4 will result in undefined behavior:
drivers/iio/temperature/maxim_thermocouple.c: In function 'maxim_thermocouple_read':
drivers/iio/temperature/maxim_thermocouple.c:141:5: error: 'ret' may be used uninitialized in this function [-Werror=maybe-uninitialized]
This probably cannot happen, but returning -EINVAL here is appropriate
and makes gcc happy and the code more robust.
Fixes: 231147ee77 ("iio: maxim_thermocouple: Align 16 bit big endian value of raw reads")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
(cherry picked from commit 32cb7d27e6)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We have #defines for all the individual sensor registers and
value/mask pairs #defined at the top of the file and used at
exactly one spot.
This is usually good if the #defines give a meaning to the
opaque magic numbers.
However in this case, the semantic meaning is inherent in the
name of the C99-addressable fields, and that means duplication
of information, and only makes the code hard to maintain since
you every time have to add a new #define AND update the site
where it is to be used.
Get rid of the #defines and just open code the values into the
appropriate struct elements. Make sure to explicitly address
the .hz and .value fields in the st_sensor_odr_avl struct
so that the meaning of all values is clear.
This patch is purely syntactic should have no semantic effect.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
We have #defines for all the individual sensor registers and
value/mask pairs #defined at the top of the file and used at
exactly one spot.
This is usually good if the #defines give a meaning to the
opaque magic numbers.
However in this case, the semantic meaning is inherent in the
name of the C99-addressable fields, and that means duplication
of information, and only makes the code hard to maintain since
you every time have to add a new #define AND update the site
where it is to be used.
Get rid of the #defines and just open code the values into the
appropriate struct elements. Make sure to explicitly address
the .hz and .value fields in the st_sensor_odr_avl struct
so that the meaning of all values is clear.
This patch is purely syntactic should have no semantic effect.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
We have #defines for all the individual sensor registers and
value/mask pairs #defined at the top of the file and used at
exactly one spot.
This is usually good if the #defines give a meaning to the
opaque magic numbers.
However in this case, the semantic meaning is inherent in the
name of the C99-addressable fields, and that means duplication
of information, and only makes the code hard to maintain since
you every time have to add a new #define AND update the site
where it is to be used.
Get rid of the #defines and just open code the values into the
appropriate struct elements. Make sure to explicitly address
the .hz and .value fields in the st_sensor_odr_avl struct
so that the meaning of all values is clear.
This patch is purely syntactic should have no semantic effect.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
