iio: adc: Use devm_krealloc_array

Now that it exists, use it instead of doing the multiplication and
checking for overflow manually.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20230509094942.396150-4-james.clark@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: adc: xilinx-ams: Convert to use fwnode_device_is_compatible()

Replace open coded fwnode_device_is_compatible() in the driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/20230119174749.76769-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: xilinx-ams: fix devm_krealloc() return value check

The clang-analyzer reported a warning: "Value stored to 'ret'
is never read".

Fix the return value check if devm_krealloc() fails to resize
ams_channels.

Fixes: d5c70627a794 ("iio: adc: Add Xilinx AMS driver")
Signed-off-by: Marco Pagani <marpagan@redhat.com>
Acked-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/20221125113112.219290-1-marpagan@redhat.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: xilinx-ams: Benefit from devm_clk_get_enabled() to simplify

Make use of devm_clk_get_enabled() to replace some code that effectively
open codes this new function.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220808204740.307667-8-u.kleine-koenig@pengutronix.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: xilinx-ams: Switch to DEFINE_SIMPLE_DEV_PM_OPS() and pm_sleep_ptr()

Using these newer macros allows the compiler to remove the unused
structure and functions when !CONFIG_PM_SLEEP + removes the need to
mark pm functions __maybe_unused.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20220621202719.13644-10-jic23@kernel.org

iio: adc: xilinx-ams: fix return error variable

Return irq instead of ret which always equals to zero here.

Fixes: d5c70627a794 ("iio: adc: Add Xilinx AMS driver")
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Lv Ruyi <lv.ruyi@zte.com.cn>
Reviewed-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: xilinx-ams: Fix single channel switching sequence

Some of the AMS channels need to be read by switching into single-channel
mode from the normal polling sequence. There was a logic issue in this
switching code that could cause the first read of these channels to read
back as zero.

It appears that the sequencer should be set back to default mode before
changing the channel selection, and the channel should be set before
switching the sequencer back into single-channel mode.

Also, write 1 to the EOC bit in the status register to clear it before
waiting for it to become set, so that we actually wait for a new
conversion to complete, and don't proceed based on a previous conversion
completing.

Fixes: d5c70627a794 ("iio: adc: Add Xilinx AMS driver")
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/20220127173450.3684318-5-robert.hancock@calian.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: xilinx-ams: Fixed wrong sequencer register settings

Register settings used for the sequencer configuration register
were incorrect, causing some inputs to not be read properly.

Fixes: d5c70627a794 ("iio: adc: Add Xilinx AMS driver")
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Reviewed-by: Michael Tretter <m.tretter@pengutronix.de>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/20220127173450.3684318-4-robert.hancock@calian.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: xilinx-ams: Fixed missing PS channels

The code forgot to increment num_channels for the PS channel inputs,
resulting in them not being enabled as they should.

Fixes: d5c70627a794 ("iio: adc: Add Xilinx AMS driver")
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Reviewed-by: Michael Tretter <m.tretter@pengutronix.de>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/20220127173450.3684318-3-robert.hancock@calian.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: xilinx-ams: Use devm_delayed_work_autocancel() to simplify code

Use devm_delayed_work_autocancel() instead of hand writing it. This is
less verbose and saves a few lines of code.

devm_delayed_work_autocancel() uses devm_add_action() instead of
devm_add_action_or_reset(). This is fine, because if the underlying memory
allocation fails, no work has been scheduled yet. So there is nothing to
undo.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/2626e6a057e40cd2271ef0e5f81d12e607bad5b4.1644776929.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: Add Xilinx AMS driver

The AMS includes an ADC as well as on-chip sensors that can be used to
sample external voltages and monitor on-die operating conditions, such
as temperature and supply voltage levels. The AMS has two SYSMON blocks.
PL-SYSMON block is capable of monitoring off chip voltage and
temperature.

PL-SYSMON block has DRP, JTAG and I2C interface to enable monitoring
from an external master. Out of these interfaces currently only DRP is
supported. Other block PS-SYSMON is memory mapped to PS.

The AMS can use internal channels to monitor voltage and temperature as
well as one primary and up to 16 auxiliary channels for measuring
external voltages.

The voltage and temperature monitoring channels also have event capability
which allows to generate an interrupt when their value falls below or
raises above a set threshold.

Co-developed-by: Manish Narani <manish.narani@xilinx.com>
Signed-off-by: Manish Narani <manish.narani@xilinx.com>
Signed-off-by: Anand Ashok Dumbre <anand.ashok.dumbre@xilinx.com>
Link: https://lore.kernel.org/r/20211203212358.31444-4-anand.ashok.dumbre@xilinx.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>