iio: dummy: Use automatic lock and direct mode cleanup.

Given we now have iio_device_claim_direct_scoped() to perform automatic
releasing of direct mode at exit from the scope that follows it, this can
be used in conjunction with guard(mutex) etc remove a lot of special case
handling.

Note that in this particular example code, there is no real reason you can't
read channels via sysfs at the same time as filling the software buffer.
To make it look more like a real driver constrain raw and processed
channel reads from occurring whilst the buffer is in use.

Reviewed-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Nuno Sa <nuno.a@analog.com>
Link: https://lore.kernel.org/r/20240128150537.44592-3-jic23@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: dummy: iio_simple_dummy: check the return value of kstrdup()

kstrdup() is also a memory allocation-related function, it returns NULL
when some memory errors happen. So it is better to check the return
value of it so to catch the memory error in time. Besides, there should
have a kfree() to clear up the allocation if we get a failure later in
this function to prevent memory leak.

Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
Link: https://lore.kernel.org/r/tencent_C920CFCC33B9CC1C63141FE1334A39FF8508@qq.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: dummy: iio_simple_dummy: Add newline after function-end

Fixes the following checkpatch.pl warning(s):

CHECK: Please use a blank line after function/struct/union/enum declarations
#46: FILE: drivers/iio/dummy/iio_simple_dummy.c:690:
}
+/*
total: 0 errors, 0 warnings, 1 checks, 22 lines checked

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: dummy: iio_simple_dummy: Demote unworthy kerneldocs and correct wrong parameter in docs

File header comments are not good candidates for kerneldoc. Neither
are generic comment blocks.

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

drivers/iio/dummy/iio_simple_dummy.c:26: warning: cannot understand function prototype: 'const struct config_item_type iio_dummy_type = '
drivers/iio/dummy/iio_simple_dummy.c:564: warning: Function parameter or member 'name' not described in 'iio_dummy_probe'
drivers/iio/dummy/iio_simple_dummy.c:564: warning: Excess function parameter 'index' description in 'iio_dummy_probe'
drivers/iio/dummy/iio_simple_dummy.c:700: warning: cannot understand function prototype: 'const struct iio_sw_device_ops iio_dummy_device_ops = '

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: core: pass parent device as parameter during allocation

The change passes the parent device to the iio_device_alloc() call. This
also updates the devm_iio_device_alloc() call to consider the device object
as the parent device by default.

Having it passed like this, should ensure that any IIO device object
already has a device object as parent, allowing for neater control, like
passing the 'indio_dev' object for other stuff [like buffers/triggers/etc],
and potentially creating iiom_xxx(indio_dev) functions.

With this patch, only the 'drivers/platform/x86/toshiba_acpi.c' needs an
update to pass the parent object as a parameter.

In the next patch all devm_iio_device_alloc() calls will be handled.

Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

spi: docs: convert to ReST and add it to the kABI bookset

While there's one file there with briefily describes the uAPI,
the documentation was written just like most subsystems: focused
on kernel developers. So, add it together with driver-api books.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

docs: i2c: convert to ReST and add to driver-api bookset

Convert each file at I2C subsystem, renaming them to .rst and
adding to the driver-api book.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 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 version 2 as
published by the free software foundation

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

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: make function argument and some structures const

Make the argument of the functions iio_sw{d/t}_group_init_type_name const
as they are only passed to the function config_group_init_type_name having
the argument as const.

Make the config_item_type structures const as they are either passed to
the functions having the argument as const or they are
stored in the const "ci_type" field of a config_item structure.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

iio:dummy: drop assignment of iio_info.driver_module

The equivalent is now done via macro magic when
the relevant register call is made. The actual structure
element will shortly go away.

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

iio: dummy: Convert IIO dummy to configfs

We register a new device type named "dummy", this will create a
configfs entry under:
* /config/iio/devices/dummy.

Creating dummy devices is now as simple as:

$ mkdir /config/iio/devices/dummy/my_dummy_device

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Move IIO Dummy Driver out of staging

This patch moves the reference IIO dummy driver from drivers/staging/iio
into a separate folder, drivers/iio/dummy and adds the proper Kconfig
and Makefile for it.

A new config menu entry called IIO dummy driver has also been added
in the Industrial I/O support menu, corresponding to this driver.

Signed-off-by: Cristina Opriceana <cristina.opriceana@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>