iio: adc: Explicitly include correct DT includes

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20230714174628.4057920-1-robh@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: stmpe-adc: 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. This one is a little unusual as
no suspend callback, but the cleanup is still worthwhile (and eventual
aim is to get rid of old macro).

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Philippe Schenker <philippe.schenker@toradex.com>
Reviewed-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20220621202719.13644-8-jic23@kernel.org

iio: stmpe-adc: use of_device_id for OF matching

The of_device_id was added to allow module autoloading, but it should be
also used to allow driver matching via Devicetree.

This also fixes W=1 warning:
drivers/iio/adc/stmpe-adc.c:357:34: error: ‘stmpe_adc_ids’ defined but not used [-Werror=unused-const-variable=]

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220501103447.111392-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: stmpe-adc: Fix wait_for_completion_timeout return value check

wait_for_completion_timeout() returns unsigned long not long.
it returns 0 if timed out, and positive if completed.
The check for <= 0 is ambiguous and should be == 0 here
indicating timeout which is the only error case

Fixes: e813dde6f833 ("iio: stmpe-adc: Use wait_for_completion_timeout")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Philippe Schenker <philippe.schenker@toradex.com>
Link: https://lore.kernel.org/r/20220412065150.14486-1-linmq006@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: stmpe-adc: Use correctly sized arguments for bit field

The find.h APIs are designed to be used only on unsigned long arguments.
This can technically result in a over-read, but it is harmless in this
case. Regardless, fix it to avoid the warning seen under -Warray-bounds,
which we'd like to enable globally:

In file included from ./include/linux/bitmap.h:9,
from ./include/linux/cpumask.h:12,
from ./arch/x86/include/asm/cpumask.h:5,
from ./arch/x86/include/asm/msr.h:11,
from ./arch/x86/include/asm/processor.h:22,
from ./arch/x86/include/asm/cpufeature.h:5,
from ./arch/x86/include/asm/thread_info.h:53,
from ./include/linux/thread_info.h:60,
from ./arch/x86/include/asm/preempt.h:7,
from ./include/linux/preempt.h:78,
from ./include/linux/spinlock.h:55,
from ./include/linux/swait.h:7,
from ./include/linux/completion.h:12,
from drivers/iio/adc/stmpe-adc.c:10:
drivers/iio/adc/stmpe-adc.c: In function 'stmpe_adc_probe':
./include/linux/find.h:98:23: warning: array subscript 'long unsigned int[0]' is partly outside array bounds of 'u32[1]' {aka 'unsigned int[1]'} [-Warray-bounds]
98 | val = *addr | ~GENMASK(size - 1, offset);
| ^~~~~
drivers/iio/adc/stmpe-adc.c:258:13: note: while referencing 'norequest_mask'
258 | u32 norequest_mask = 0;
| ^~~~~~~~~~~~~~

Signed-off-by: Kees Cook <keescook@chromium.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: adc: stmpe-adc: Cleanup endian type of local variable

Nothing stops data being of type __be16, which fixes the warning:

CHECK drivers/iio/adc/stmpe-adc.c
drivers/iio/adc/stmpe-adc.c:202:29: warning: cast to restricted __be16
drivers/iio/adc/stmpe-adc.c:202:29: warning: cast to restricted __be16
drivers/iio/adc/stmpe-adc.c:202:29: warning: cast to restricted __be16
drivers/iio/adc/stmpe-adc.c:202:29: warning: cast to restricted __be16

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: <philippe.schenker@toradex.com>

iio: stmpe-adc: Reset possible interrupts

Clear any interrupt that still is on the device on every channel
this driver is activated for in probe and specific channels in
the timeout handler.

Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: stmpe-adc: Use wait_for_completion_timeout

Use wait_for_completion_timeout instead of
wait_for_completion_interuptible_timeout.

The interruptible variant gets constantly interrupted if a user
program is compiled with the -pg option.
The killable variant was not used due to the fact that a second
program, reading on this device, that gets killed is then also killing
that wait.

Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: stmpe-adc: Enable all stmpe-adc interrupts just once

This commit will enable the interrupts of all channels handled by this
driver only once in the probe function.

This will improve performance because one byte less has to be written over
i2c on each read out of the adc. On the fastest ADC mode this will improve
read out speed by 15%.

Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: stmpe-adc: Reinit completion struct on begin conversion

In some cases, the wait_completion got interrupted. This caused the
error-handling to mutex_unlock the function. The before turned on
interrupt then got called anyway. In the ISR then completion() was
called causing wrong adc-values returned in a following adc-readout.

Reinitialise completion struct to make sure the counter is zero
when beginning a new adc-conversion.

Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: stmpe-adc: Add compatible name

Add the compatible name to the driver so it gets loaded when the proper
node in DT is detected.

Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: stmpe-adc: Remove unnecessary assignment

Remove unnecessary assignment. This could potentially cause an issue, if
the wait function runs into a timeout. Furthermore is this assignment also
not there in stmpe_read_temp()

Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: stmpe-adc: Shuffle an if statement around in stmpe_adc_isr

When building with -Wsometimes-uninitialized, Clang warns:

drivers/iio/adc/stmpe-adc.c:204:13: warning: variable 'data' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]

Clang can't tell that data will never be used uninitialized because the
two if statements take care of all cases. Remove the first if statement
and make it the else branch of the second one so that it is apparent to
Clang that all cases are covered.

Link: https://github.com/ClangBuiltLinux/linux/issues/387
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: NIck Desaulniers <ndesaulniers@google.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: add STMPE ADC driver using IIO framework

This adds an ADC driver for the STMPE device using the industrial
input/output interface. The driver supports raw reading of values.
The driver depends on the MFD STMPE driver. If the touchscreen
block is enabled too, only four of the 8 ADC channels are available.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>
Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>