This implements buffered reads for the ad4695 driver using the typical
triggered buffer implementation, including adding a soft timestamp
channel.
The chip has 4 different modes for doing conversions. The driver is
using the advanced sequencer mode since that is the only mode that
allows individual configuration of all aspects each channel (e.g.
bipolar config currently and oversampling to be added in the future).
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://patch.msgid.link/20240813-iio-adc-ad4695-buffered-read-v2-1-9bb19fc1924b@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
When a machine enters a sleep state while a trigger is associated to
an iio device that trigger is not resumed after exiting the sleep state:
provide iio device drivers a way to suspend and resume
the associated trigger to solve the aforementioned bug.
Each iio driver supporting external triggers is expected to call
iio_device_suspend_triggering before suspending,
and iio_device_resume_triggering upon resuming.
Signed-off-by: Denis Benato <benato.denis96@gmail.com>
Link: https://patch.msgid.link/20240807185619.7261-2-benato.denis96@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Add scaling support to STM32 DFSDM.
When used in an analog context, a DFSDM filter typically converts the data
from a sigma delta modulator. The IIO device associated to the DFSDM
filter provides these data as raw data.
The IIO device can provide scaling information (voltage and offset) to
allow conversion of raw data into physical values.
With the new binding based on IIO backend framework, the sigma delta
modulators are defined as backends providing scaling information.
The scaling is not supported with legacy binding.
Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://patch.msgid.link/20240730084640.1307938-10-olivier.moysan@foss.st.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The legacy sd modulator driver registers the sigma delta modulator as
an IIO channel provider. This implementation is not convenient when the
SD modulator has to be cascaded with another IIO device. The scaling
information is distributed across devices, which makes it difficult to
report consistent scaling data on IIO devices.
The solution is to expose these cascaded IIO devices as an aggregate
device, which report global scaling information.
Add IIO backend support to SD modulator to allow scaling information
management.
Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
Link: https://patch.msgid.link/20240730084640.1307938-9-olivier.moysan@foss.st.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Move to generic channels binding to ease new backend framework adoption
and prepare the convergence with MDF IP support on STM32MP2 SoC family.
Legacy binding:
DFSDM is an IIO channel consumer.
SD modulator is an IIO channels provider.
The channel phandles are provided in DT through io-channels property
and channel indexes through st,adc-channels property.
New binding:
DFSDM is an IIO channel provider.
The channel indexes are given by reg property in channel child node.
This new binding is intended to be used with SD modulator IIO backends.
It does not support SD modulator legacy IIO devices.
The st,adc-channels property presence is used to discriminate
between legacy and backend bindings.
The support of the DFSDM legacy channels and SD modulator IIO devices
is kept for backward compatibility.
Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
Link: https://patch.msgid.link/20240730084640.1307938-8-olivier.moysan@foss.st.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The legacy sd modulator driver registers the sigma delta modulator as
an IIO channel provider. This implementation is not convenient when the
SD modulator has to be cascaded with another IIO device. The scaling
information is distributed across devices, which makes it difficult to
report consistent scaling data on IIO devices.
The solution is to expose these cascaded IIO devices as an aggregate
device, which report global scaling information.
Add IIO backend support to SD modulator to allow scaling information
management.
Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20240730084640.1307938-6-olivier.moysan@foss.st.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Change the DFSDM binding to use the new IIO backend framework,
along with the adoption of IIO generic channels.
This binding change allows to add scaling support to the DFSDM.
Keep the legacy binding as deprecated for backward compatibility.
The io-backends property is supported only in generic IIO channel
binding.
- Channel description with the generic binding (Audio and Analog):
Properties superseded by generic properties:
st,adc-channels: becomes "reg" property in channel node
st,adc-channel-names: becomes "label" property in channel node
Properties moved to channel child node:
st,adc-channel-types: becomes st,adc-channel-type
st,adc-channel-clk-src, st,adc-alt-channel
- Analog binding:
DFSDM filter channel is configured as an IIO backend consumer.
Add io-backends property in channel child nodes.
DFSDM is no more configured as a channel consumer from SD modulator.
Use of io-channels in DFSDM node is deprecated.
- Audio binding:
DFSDM audio DAI is configured as a channel consumer from DFSDM filter.
No change compare to legacy.
Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20240730084640.1307938-5-olivier.moysan@foss.st.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Add iio_backend_read_scale() and iio_backend_read_offset() services
to read channel scale and offset from an IIO backbend device.
Also add a read_raw callback which replicates the read_raw callback of
the IIO framework, and is intended to request miscellaneous channel
attributes from the backend device.
Both scale and offset helpers use this callback.
Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://patch.msgid.link/20240730084640.1307938-2-olivier.moysan@foss.st.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
During setup the st->adc_control is 0, which corresponds to a continuous
conversion mode. The reset value for channel 1 is to enable it. The
combined effect of these two is that the ADC will start conversions for
channel 1 without them being read.
This is not neccessarily a problem, but it is an unexpected behavior.
Set the ADC state to idle during setup to avoid this.
Signed-off-by: Dumitru Ceclan <dumitru.ceclan@analog.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://patch.msgid.link/20240731-ad7124-fix-v1-4-46a76aa4b9be@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The ad7124_init_config_vref() function writes the AD7124_ADC_CONTROL
register for each channel that is configured to use the internal
reference.
The ad7124_write_config()function performs 7 SPI transfers for
configuring 2 registers: config_x and filter_x.
Reduce the number of SPI transfers:
-during the probe by only setting the st->adc_control value in
ad7124_init_config_vref() and writing to the device only at the end of
ad7124_setup().
-in ad7124_write_config() by grouping writes to the same register.
Signed-off-by: Dumitru Ceclan <dumitru.ceclan@analog.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://patch.msgid.link/20240731-ad7124-fix-v1-3-46a76aa4b9be@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
One useful thing to do (in case of problems) in this high speed devices
with digital interfaces is to try different test patterns to see if the
interface is working properly (and properly calibrated). Hence add this
to debugfs.
On top of this, for some test patterns, the backend may have a matching
validator block which can be helpful in identifying possible issues. For
the other patterns some test equipment must be used so one can look into
the signal and see how it looks like.
Hence, we also add the backend debugfs interface with
iio_backend_debugfs_add().
Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://patch.msgid.link/20240802-dev-iio-backend-add-debugfs-v2-8-4cb62852f0d0@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This adds a basic debugfs interface for backends. Two new ops are being
added:
* debugfs_reg_access: Analogous to the core IIO one but for backend
devices.
* debugfs_print_chan_status: One useful usecase for this one is for
testing test tones in a digital interface and "ask" the backend to
dump more details on why a test tone might have errors.
Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://patch.msgid.link/20240802-dev-iio-backend-add-debugfs-v2-2-4cb62852f0d0@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
