iio: amplifiers: hmc425a: add support for LTC6373 Instrumentation Amplifier

This adds support for LTC6373 36 V Fully-Differential Programmable-Gain
Instrumentation Amplifier with 25 pA Input Bias Current.
The user can program the gain to one of seven available settings through
a 3-bit parallel interface (A2 to A0).

Signed-off-by: Dumitru Ceclan <mitrutzceclan@gmail.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240220153553.2432-6-mitrutzceclan@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: amplifiers: hmc425a: use pointers in match table

Change the match table to use pointers instead of device ids.
Remove type from state as it is not used anymore.

Also make the chip_info structures const.

Signed-off-by: Dumitru Ceclan <mitrutzceclan@gmail.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240220153553.2432-4-mitrutzceclan@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: amplifiers: hmc425a: move conversion logic

Move gain-dB<->code conversion logic from read_raw and write_raw to
chip_info callbacks.

Signed-off-by: Dumitru Ceclan <mitrutzceclan@gmail.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240220153553.2432-2-mitrutzceclan@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: amplifiers: hmc425a: add support for ADRF5740 Attenuator

This adds support for the Analog Devices ADRF5740 2 dB LSB, 4-Bit,
Silicon Digital Attenuator, 10 MHz to 60 GHz.
The default (maximum) gain is also set at probe time, with GPIO lines
driven high to achieve maximum gain, in contrast to other devices
where GPIOs need to be driven low.

Signed-off-by: Ana-Maria Cusco <ana-maria.cusco@analog.com>
Link: https://lore.kernel.org/r/20231113102535.51074-2-anamaria.cuscoo@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: amplifiers: hmc425a: Add Support HMC540S 4-bit Attenuator

This adds support for the Analog Devices HMC540s 1 dB LSB
Silicon MMIC 4-Bit Digital Positive Control Attenuator, 0.1 - 8 GHz

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Ana-Maria Cusco <ana-maria.cusco@analog.com>
Link: https://lore.kernel.org/r/20230816110906.144540-1-ana-maria.cusco@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: amplifier: hmc425a: 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() and drop the pointer to the regulator.
This simplifies code and makes it less tempting to add manual control
for the regulator which is also controlled by devm.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Acked-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/8b1193fdefb231a6d721e2bded52c48e56039c20.1660934107.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: amplifiers: hmc425a: Make use of device properties

Convert the module to be property provider agnostic and allow
it to be used on non-OF platforms.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220203121624.75515-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio:amplifiers:hmc425a: Suppress clang W=1 warning about pointer to enum conversion.

Cast to a uintptr_t rather than directly to the enum.

As per the discussion in below linked media patch.

Link: https://lore.kernel.org/linux-media/CAK8P3a2ez6nEw4d+Mqa3XXAz0RFTZHunqqRj6sCt7Y_Eqqs0rw@mail.gmail.com/
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20211128172445.2616166-6-jic23@kernel.org

iio: amplifiers: hmc425a: Simplify with dev_err_probe()

Common pattern of handling deferred probe can be simplified with
dev_err_probe(). Less code and also it prints the error value.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20200829064726.26268-10-krzk@kernel.org
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: amplifiers: hmc425a: Add support for HMC425A attenuator

This patch adds support for the HMC425A 0.5 dB LSB GaAs MMIC 6-BIT
DIGITAL POSITIVE CONTROL ATTENUATOR, 2.2 - 8.0 GHz.

Datasheet:
https://www.analog.com/media/en/technical-documentation/data-sheets/hmc425A.pdf

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Beniamin Bia <beniamin.bia@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>