iio: adc: palmas_gpadc: Drop duplicated the in comment.

In line 460 of the palmas_gpadc.c file, fix kernel comment errors.

Signed-off-by: Andy Shen Shen <shengaoya@inspur.com>
Link: https://lore.kernel.org/r/20230921031444.63594-1-shengaoya@inspur.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: Remove redundant dev_err_probe()

There is no need to call the dev_err() function directly to print a custom
message when handling an error from either the platform_get_irq() or
platform_get_irq_byname() functions as both are going to display an
appropriate error message in case of a failure.

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20230727073912.4178659-1-ruanjinjie@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

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: palmas: Remove the unneeded include <linux/i2c.h>

This driver does not use i2c, so there is no point in including
<linux/i2c.h>

Remove it.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/9d23cd04d7f99dc8d813584aae5268b57f92fcd8.1682320298.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas: fix off by one bugs

Valid values for "adc_chan" are zero to (PALMAS_ADC_CH_MAX - 1).
Smatch detects some buffer overflows caused by this:
drivers/iio/adc/palmas_gpadc.c:721 palmas_gpadc_read_event_value() error: buffer overflow 'adc->thresholds' 16 <= 16
drivers/iio/adc/palmas_gpadc.c:758 palmas_gpadc_write_event_value() error: buffer overflow 'adc->thresholds' 16 <= 16

The effect of this bug in other functions is more complicated but
obviously we should fix all of them.

Fixes: a99544c6c883 ("iio: adc: palmas: add support for iio threshold events")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/14fee94a-7db7-4371-b7d6-e94d86b9561e@kili.mountain
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas: don't alter event config on suspend/resume

The event config is controlled through the IIO events subsystem and
device wakeup is controlled by /sys/devices/.../power/wakeup. Let's keep
those two knobs independent.

Signed-off-by: Patrik Dahlström <risca@dalakolonin.se>
Link: https://lore.kernel.org/r/20230408114825.824505-10-risca@dalakolonin.se
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas: add support for iio threshold events

The palmas gpadc block has support for monitoring up to 2 ADC channels
and issue an interrupt if they reach past a set threshold. This change
hooks into the IIO events system and exposes to userspace the ability to
configure these threshold values for each channel, but only allow up to
2 such thresholds to be enabled at any given time. Trying to enable a
third channel will result in an error.

Userspace is expected to input calibrated, as opposed to raw, values as
threshold. However, it is not enough to do the opposite of what is done
when converting the other way around. To account for tolerances in the
ADC, the calculated raw threshold should be adjusted based on the ADC
specifications for the device. These specifications include the integral
nonlinearity (INL), offset, and gain error. To adjust the high
threshold, use the following equation:

(calibrated value + INL) * Gain error + offset = maximum value [1]

Likewise, use the following equation for the low threshold:

(calibrated value - INL) * Gain error - offset = minimum value

The gain error is a combination of gain error, as listed in the
datasheet, and gain error drift due to temperature and supply. The exact
values for these specifications vary between palmas devices. This patch
sets the values found in TWL6035, TWL6037 datasheet.

[1] TI Application Report, SLIA087A, Guide to Using the GPADC in
TPS65903x, TPS65917-Q1, TPS65919-Q1, and TPS65916 Devices.

Signed-off-by: Patrik Dahlström <risca@dalakolonin.se>
Link: https://lore.kernel.org/r/20230408114825.824505-9-risca@dalakolonin.se
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas: always reset events on unload

This prevents leaving the adc in freerunning mode when removing the
driver.

Signed-off-by: Patrik Dahlström <risca@dalakolonin.se>
Link: https://lore.kernel.org/r/20230408114825.824505-8-risca@dalakolonin.se
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas: move eventX_enable into palmas_adc_event

It just makes more sense to have all information regarding adc events in
one place.

Signed-off-by: Patrik Dahlström <risca@dalakolonin.se>
Link: https://lore.kernel.org/r/20230408114825.824505-7-risca@dalakolonin.se
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas: use iio_event_direction for threshold polarity

Instead of having high_threshold > 0 as an indicator for upper threshold
event and lower threshold event otherwise, use enum iio_event_direction
instead. This is hopefully less ambiguous.

Signed-off-by: Patrik Dahlström <risca@dalakolonin.se>
Link: https://lore.kernel.org/r/20230408114825.824505-6-risca@dalakolonin.se
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas: replace "wakeup" with "event"

The palmas gpadc block has support for monitoring up to 2 ADC channels
and issue an interrupt if they reach past a set threshold. This is
currently used to wake up the system from sleep, but the functionality
is more generic than that. As such, change the naming of functions and
variables to refer to it as events instead, except during suspend and
resume where wakeup still make sense.

Signed-off-by: Patrik Dahlström <risca@dalakolonin.se>
Link: https://lore.kernel.org/r/20230408114825.824505-5-risca@dalakolonin.se
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas: remove adc_wakeupX_data

It does not seem to be used by anyone and later patches in this series
are made simpler by first removing this. There is now a lot of dead code
that cannot be reached, until later patches revive it. Arguably, this is
preferred over removing the code only to add it again.

Signed-off-by: Patrik Dahlström <risca@dalakolonin.se>
Link: https://lore.kernel.org/r/20230408114825.824505-4-risca@dalakolonin.se
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas: Take probe fully device managed.

Review of a recent fix highlighted that this driver could be trivially
converted to be entirely devm managed.

That fix should be applied to resolve the fix in a fashion easy to back port
even though this change removes the relevant code.

[1] https://patchwork.kernel.org/project/linux-iio/patch/20230313205029.1881745-1-risca@dalakolonin.se/

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: Patrik Dahlström <risca@dalakolonin.se>
Reviewed-by: Patrik Dahlström <risca@dalakolonin.se>
Link: https://lore.kernel.org/r/20230318163039.56115-1-jic23@kernel.org

iio: adc: palmas_gpadc: fix NULL dereference on rmmod

Calling dev_to_iio_dev() on a platform device pointer is undefined and
will make adc NULL.

Signed-off-by: Patrik Dahlström <risca@dalakolonin.se>
Link: https://lore.kernel.org/r/20230313205029.1881745-1-risca@dalakolonin.se
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: palmas: shut up warning about calibration mismatch (due to noise)

Although technically checking for ADC values below 0 is correct,
because they are outside of the calibration values, there is usually
noise which spuriously fills the console log with error messages if
calculated input voltage gets close to 0V.

Ignore small negative calculated values, but clamp them to 0.

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Link: https://lore.kernel.org/r/1cee45bfc3fa2ab59dcc17242fb52468035360a1.1646743982.git.hns@goldelico.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio:adc:palmas_gpadc: Switch from CONFIG_PM_SLEEP guards to pm_sleep_ptr()

Letting the compiler remove these functions when the kernel is built
without CONFIG_PM_SLEEP support is simpler and less error prone than the
use of #ifdef based config guards.

Removing instances of this approach from IIO also stops them being
copied into new drivers.

In this case SIMPLE_DEV_PM_OPS() could have been used previously.
Now we have DEFINE_SIMPLE_DEV_PM_OPS() which also deals with letting
the compiler remove the structure and functions so use that instead.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20220130193147.279148-13-jic23@kernel.org

iio: adc: Fix incorrect exit of for-loop

Currently the for-loop that scans for the optimial adc_period iterates
through all the possible adc_period levels because the exit logic in
the loop is inverted. I believe the comparison should be swapped and
the continue replaced with a break to exit the loop at the correct
point.

Addresses-Coverity: ("Continue has no effect")
Fixes: e08e19c331fb ("iio:adc: add iio driver for Palmas (twl6035/7) gpadc")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20210730071651.17394-1-colin.king@canonical.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas_gpadc: Replace indio_dev->mlock with own device lock

As part of the general cleanup of indio_dev->mlock, this change replaces
it with a local lock on the device's state structure.

This is part of a bigger cleanup.
Link: https://lore.kernel.org/linux-iio/CA+U=Dsoo6YABe5ODLp+eFNPGFDjk5ZeQEceGkqjxXcVEhLWubw@mail.gmail.com/

Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
Link: https://lore.kernel.org/r/20200928131333.36646-2-mircea.caprioru@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: use getter/setter functions

Use getter and setter functions, for a variety of data types.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Link: https://lore.kernel.org/r/20210209211315.1261791-1-Julia.Lawall@inria.fr
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas_gpadc: use module_platform_driver to simplify the code

module_platform_driver() makes the code simpler by eliminating
boilerplate code.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Link: https://lore.kernel.org/r/20200914065401.3726354-1-liushixin2@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: palmas_gpadc: Demote non-conforming kerneldoc header

Very few of the struct attributes have been documented here.

Fixes the following W=1 kernel build warning(s):

drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'dev' not described in 'palmas_gpadc'
drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'palmas' not described in 'palmas_gpadc'
drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'irq' not described in 'palmas_gpadc'
drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'irq_auto_0' not described in 'palmas_gpadc'
drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'irq_auto_1' not described in 'palmas_gpadc'
drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'adc_info' not described in 'palmas_gpadc'
drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'conv_completion' not described in 'palmas_gpadc'
drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'wakeup1_data' not described in 'palmas_gpadc'
drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'wakeup2_data' not described in 'palmas_gpadc'
drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'wakeup1_enable' not described in 'palmas_gpadc'
drivers/iio/adc/palmas_gpadc.c:114: warning: Function parameter or member 'wakeup2_enable' not described in 'palmas_gpadc'

Cc: Pradeep Goudagunta <pgoudagunta@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.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>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 372

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 135 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531081036.435762997@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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: palmas_gpadc: retrieve a valid iio_dev in suspend/resume

The suspend/resume functions were using dev_to_iio_dev() to get
the iio_dev. That only works on IIO dev's. Use dev_get_drvdata()
for a platform device to get the correct iio_dev.

Signed-off-by: Alison Schofield <amsfield22@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: adc: palmas: Drop IRQF_EARLY_RESUME flag

Palmas gpadc IRQs are nested threaded and this flag is not required for nested
irqs anymore, since commit 3c646f2c6aa9 ("genirq: Don't suspend nested_thread
irqs over system suspend") was merged.

Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Peter Meerwald <pmeerw@pmeerw.net>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:adc:palmas: add DT support

Code was found at:
https://android.googlesource.com/kernel/tegra/+/a90856a6626d502d42c6e7abccbdf9d730b36270%5E%21/#F1

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Marek Belisko <marek@goldelico.com> [Fixed minor typos + add channels list to documentation]
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:adc: add iio driver for Palmas (twl6035/7) gpadc

This driver code was found as:

https://android.googlesource.com/kernel/tegra/+/aaabb2e045f31e5a970109ffdaae900dd403d17e/drivers/staging/iio/adc

Fixed various compilation issues and test this driver on omap5 evm.

Signed-off-by: Pradeep Goudagunta <pgoudagunta@nvidia.com>
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Marek Belisko <marek@goldelico.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>