iio: adc: ad7476: simplify using devm_regulator_get_enable()

Drop open-coded pattern: 'devm_regulator_get(), regulator_enable(),
add_action_or_reset(regulator_disable)' and use the
devm_regulator_get_enable()

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Acked-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/33070d66b9b976acac1cee5570facef9278b6b61.1660934107.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: ad7476: Fix alignment for DMA safety

____cacheline_aligned is an insufficient guarantee for non-coherent DMA
on platforms with 128 byte cachelines above L1. Switch to the updated
IIO_DMA_MINALIGN definition.

Update the comment to reflect that DMA safety 'may' require separate
cachelines.

Fixes tag is unlikely to be the actual introdution of the problem but is
far enough back to cover any likely backporting.

Fixes: 7a28fe3c93d6 ("staging:iio:ad7476: Squash driver into a single file.")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20220508175712.647246-14-jic23@kernel.org

iio: adc: remove unused private data assigned with spi_set_drvdata()

These were usually used before the conversion to devm_ functions, so that
the remove hook would be able to retrieve the pointer and do cleanups on
remove.
When the conversion happened, they should have been removed, but were
omitted.

Some drivers were copied from drivers that fit the criteria described
above. In any case, in order to prevent more drivers from being used as
example (and have spi_set_drvdata() needlessly set), this change removes it
from the IIO ADC group.

Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Link: https://lore.kernel.org/r/20210513111035.77950-1-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio:adc:ad7476: Handle the different regulators used by various parts.

Not all of the parts supported by this driver use single supply.
Hence we add chip_info fields to say what additional supplies exist
and in the case of vref, ensure that is used for the reference voltage
rather than vcc.

One corner case is the ad7091r which has an internal reference that
can be over-driven by an external reference connected on the vref pin.
To handle that force_ext_vref is introduced and set if an optional
vref regulator is present.

Tested using really simple QEMU model and some fixed regulators.

The devm_add_action_or_reset() callback is changed to take the
regulator as it's parameter so we can use one callback for all the
different regulators without having to store pointers to them in
the iio_priv() structure.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michael Hennerich <michael.hennerich@analog.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20210425163154.73209-2-jic23@kernel.org

iio:adc:ad7476: Fix remove handling

This driver was in an odd half way state between devm based cleanup
and manual cleanup (most of which was missing).
I would guess something went wrong with a rebase or similar.
Anyhow, this basically finishes the job as a precursor to improving
the regulator handling.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Fixes: 4bb2b8f94ace3 ("iio: adc: ad7476: implement devm_add_action_or_reset")
Cc: Michael Hennerich <michael.hennerich@analog.com>
Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Cc: <Stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210401171759.318140-2-jic23@kernel.org

iio: adc: ad7476: Add LTC2314-14 support

The LTC2314-14 is a 14-bit, 4.5Msps, serial sampling A/D converter that draws only
6.2mA from a wide range analog supply adjustable from 2.7V to 5.25V.

Signed-off-by: Dragos Bogdan <dragos.bogdan@analog.com>
Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
Link: https://lore.kernel.org/r/20201216083639.89425-1-mircea.caprioru@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: Remove superfluous of_node assignments

If a driver does not assign an of_node to a IIO device to IIO core will
automatically assign the of_node of the parent device. This automatic
assignment is done in the iio_device_register() function.

There is a fair amount of drivers that currently manually assign the
of_node of the IIO device. All but 4 of them can make use of the automatic
assignment though.

The exceptions are:
* mxs-lradc-adc: Which uses the of_node of the parent of the parent.
* stm32-dfsdm-adc, stm32-adc and stm32-dac: Which reference the of_node
assigned to the IIO device before iio_device_register() is called.

All other drivers are updated to use automatic assignment. This reduces
the amount of boilerplate code involved in setting up the IIO device.

The patch has mostly been auto-generated with the following semantic patch

// <smpl>
@exists@
expression indio_dev;
expression parent;
@@
indio_dev = \(devm_iio_device_alloc\|iio_device_alloc\)(&parent, ...)
...
-indio_dev->dev.of_node = parent.of_node;

@exists@
expression indio_dev;
expression parent;
@@
indio_dev = \(devm_iio_device_alloc\|iio_device_alloc\)(parent, ...)
...
-indio_dev->dev.of_node = parent->of_node;
// </smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: remove left-over comments about parent assignment

These were obtained by doing a 'git diff | grep \/\*', in the previous diff
to find comments. These needed a bit more manual review, as the semantic
patch isn't great for catching these.

The result is:
/* Initialize Counter device and driver data */
/* Initialize IIO device */
/* Establish that the iio_dev is a child of the spi device */
/* Estabilish that the iio_dev is a child of the spi device */
/* Initiate the Industrial I/O device */
/* Establish that the iio_dev is a child of the device */
- /* establish that the iio_dev is a child of the i2c device */
- /* establish that the iio_dev is a child of the i2c device */
/* This is only used for removal purposes */
/* setup the industrialio driver allocated elements */
/* variant specific configuration */
/* Setup for userspace synchronous on demand sampling. */
st->readback_delay_us += 5; /* Add tWAIT */
- /* Establish that the iio_dev is a child of the i2c device */
/* Establish that the iio_dev is a child of the i2c device */

Out of which, 4 are really left-over comments about parent assignment.
3 of them are removed by the semantic patch, as the comment removed (by
spatch) would be for an empty line.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: remove explicit IIO device parent assignment

This patch applies the semantic patch:
@@
expression I, P, SP;
@@
I = devm_iio_device_alloc(P, SP);
...
- I->dev.parent = P;

It updates 302 files and does 307 deletions.
This semantic patch also removes some comments like
'/* Establish that the iio_dev is a child of the i2c device */'

But this is is only done in case where the block is left empty.

The patch does not seem to cover all cases. It looks like in some cases a
different variable is used in some cases to assign the parent, but it
points to the same reference.
In other cases, the block covered by ... may be just too big to be covered
by the semantic patch.

However, this looks pretty good as well, as it does cover a big bulk of the
drivers that should remove the parent assignment.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: ad7476: remove redundant null check on an array

The null check on st->chip_info->convst_channel is redundant because
convst_channel is a 2 element array of struct iio_chan_spec objects
and this can never be null. Fix this by removing the null check.

Addresses-Coverity: ("Array compared against 0")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: ad7476: implement devm_add_action_or_reset

Use devm_add_action_or_reset to automatically disable the device
when it is removed or an error occurs during probe routine.

Signed-off-by: Beniamin Bia <beniamin.bia@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: ad7476: Add AD7091 support

AD7091R is already supported by this driver. While AD7091R allows the
choice of an internal or an external voltage reference, for AD7091 the
reference is only provided by VDD. Since this information is anyway
obtained through the "vcc" regulator, no other driver changes are
required for adding AD7091 support as well.

Signed-off-by: Dragos Bogdan <dragos.bogdan@analog.com>
Signed-off-by: Beniamin Bia <beniamin.bia@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: ad7476: Add IIO_CHAN_INFO_RAW for AD7091R

When CONVST signal is generated internally, IIO_CHAN_INFO_RAW can be
made available for AD7091R for single reads. This patch enables it and
makes supporting more devices by this driver easier.

Signed-off-by: Dragos Bogdan <dragos.bogdan@analog.com>
Signed-off-by: Beniamin Bia <beniamin.bia@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: ad7476: Generate CONVST signal internally

Compared to the other supported parts, AD7091R are dependent of
a CONVST signal that initiates the conversion. At this moment, only
sampling in buffered mode is supported for AD7091R and the only
option until now was to generate this signal externally using an
IIO trigger. This patch adds the option of generating it internally,
more compatible triggers being available in this case.

Also, it is an intermediate step of adding support more devices.

Signed-off-by: Dragos Bogdan <dragos.bogdan@analog.com>
Signed-off-by: Beniamin Bia <beniamin.bia@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: ad7476: Add support for TI ADS786X ADCs

Add support for Texas Instruments ADS7866, ADS7867 and ADS7868
8/10/12 bit Single channel ADC.

Datasheet: http://www.ti.com/lit/ds/symlink/ads7868.pdf

Signed-off-by: Ricardo Ribalda Delgado <ricardo@ribalda.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers: iio: Update MODULE AUTHOR email address

no functional changes

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: change license description

Using an SPDX tag. Remove a license notice to keep
the whole purpose of using an SPDx id.

Signed-off-by: Milan Stevanovic <milan.o.stevanovic@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: driver for ti adc081s/adc101s/adc121s

Add Linux device driver for TI single-channel CMOS
8/10/12-bit analog-to-digital converter with a
high-speed serial interface.

Signed-off-by: Milan Stevanovic <milan.o.stevanovic@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio:adc: drop assign iio_info.driver_module and iio_trigger_ops.owner

The equivalent of both of these are now done via macro magic when
the relevant register calls are made. The actual structure
elements will shortly go away.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>

iio: adc: add missing of_node references to iio_dev

Adding missing indio_dev->dev.of_node references to allow iio consumers
to access the device channels.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:core: timestamping clock selection support

Adds a new per-device sysfs attribute "current_timestamp_clock" to allow
userspace to select a particular POSIX clock for buffered samples and
events timestamping.

Following clocks, as listed in clock_gettime(2), are supported:
CLOCK_REALTIME, CLOCK_MONOTONIC, CLOCK_MONOTONIC_RAW,
CLOCK_REALTIME_COARSE, CLOCK_MONOTONIC_COARSE, CLOCK_BOOTTIME and
CLOCK_TAI.

Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Acked-by: Sanchayan Maity <maitysanchayan@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: adc: ad7476: use iio helper function to guarantee direct mode

Replace the code that guarantees the device stays in direct mode
with iio_device_claim_direct_mode() which does same.

Signed-off-by: Alison Schofield <amsfield22@gmail.com>
Acked-by: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

spi: Drop owner assignment from spi_drivers

An spi_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

iio:adc:ad7476: Use GENMASK() macro

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:ad7476: Report scale as fractional value

Move the complexity of calculating the fixed point scale to the core.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:ad7476: Use iio_push_to_buffers_with_timestamp()

Makes the code a bit shorter and less ugly.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: adc: ad7476: Use devm_* APIs

devm_* APIs are device managed and make code simpler.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:adc:ad7476 move to info_mask_(shared_by_type/separate)

The original info_mask is going away in favour of the broken out versions.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>

Drivers: iio: remove __dev* attributes.

CONFIG_HOTPLUG is going away as an option. As a result, the __dev*
markings need to be removed.

This change removes the use of __devinit, __devexit_p, and __devexit
from these drivers.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging:iio: Add support for multiple buffers

Route all buffer writes through the demux.
Addition or removal of a buffer results in tear down and
setup of all the buffers for a given device.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Tested-by: srinivas pandruvada <srinivas.pandruvada@intel.com>

iio: ad7476: Add support for the ad7091r

Add support for the ad7091r 12 bit ADC to the ad7476 driver. Although the
ad7091r is not really related to any of the other devices supported by this
driver, luckily for us there are not so many ways (which are not totally insane)
how sampling a single channel ADC via SPI can be implemented and support for the
ad7091r can be added to the driver with just a few adjustments.

The ad7091r requires an external "conversion start" pulse to start a sample
conversion. After the conversion has finished the result can be read via SPI. We
depend on a IIO trigger to generate this signal, as a result only sampling in
buffered mode and not in manual mode is available.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:ad7476: Add support for ad7273/ad7274/ad7276/ad7277/ad7278

The ad7276/ad7277/ad7278 are similar to the ad7476/ad7477/ad7478 but have the
same number of leading zeros as the ad7940. The ad7273/ad7274 have a extra pin
for VREF where as for the ad7276/ad7277/ad7278 VREF is taken from VDD, but
otherwise they are compatible to the ad7276/ad7277.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:ad7476: Add ad7940 support

The AD7940 is a single channel 14 bit ADC similar to the ADCs already supported
by the ad7476 driver, but it does have a different shift factor.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:ad7476: Add ad7910/ad7920 device table entries

The ad7910/ad7920 are software compatible to the ad7467/ad7466.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Move ad7476 driver out of staging

The ad7476 driver is a driver for simple single channel ADCs. The driver does
not export any experimental or custom ABI files nor do the static code check
tools report any issues, so move the driver out of staging.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>