media: i2c: max2175: convert to use maple tree register cache

The maple tree register cache is based on a much more modern data structure
than the rbtree cache and makes optimisation choices which are probably
more appropriate for modern systems than those made by the rbtree cache.

Signed-off-by: Bo Liu <liubo03@inspur.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

media: Switch i2c drivers back to use .probe()

After commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new()
call-back type"), all drivers being converted to .probe_new() and then
commit 03c835f498b5 ("i2c: Switch .probe() to not take an id parameter")
convert back to (the new) .probe() to be able to eventually drop
.probe_new() from struct i2c_driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

i2c: Make remove callback return void

The value returned by an i2c driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)

So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.

Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com>
Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Crt Mori <cmo@melexis.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Marek Behún <kabel@kernel.org> # for leds-turris-omnia
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Machata <petrm@nvidia.com> # for mlxsw
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> # for surface3_power
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> # for bmc150-accel-i2c + kxcjk-1013
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for media/* + staging/media/*
Acked-by: Miguel Ojeda <ojeda@kernel.org> # for auxdisplay/ht16k33 + auxdisplay/lcd2s
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for versaclock5
Reviewed-by: Ajay Gupta <ajayg@nvidia.com> # for ucsi_ccg
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio
Acked-by: Peter Rosin <peda@axentia.se> # for i2c-mux-*, max9860
Acked-by: Adrien Grassein <adrien.grassein@gmail.com> # for lontium-lt8912b
Reviewed-by: Jean Delvare <jdelvare@suse.de> # for hwmon, i2c-core and i2c/muxes
Acked-by: Corey Minyard <cminyard@mvista.com> # for IPMI
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> # for drivers/power
Acked-by: Krzysztof Hałasa <khalasa@piap.pl>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

media: i2c: max2175: Use rbtree rather than flat register cache

The max2175 uses a flat register cache but supplies only a single default
value and has many volatile registers. This is a poor fit for a flat cache
since the cache will assume a default of zero for any register not yet
written which can lead to bugs for example when regmap_update_bits()
suppresses a noop write. A rbtree cache is a much better fit, this will
only cache default values and values that have been written to the device
with any reads of uncached values going to the hardware. Convert the driver
to use a rbtree cache.

Since the device is controlled via I2C the cost of manging the rbtree
should be immaterial compared to the cost of accessing the device.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

media: media/i2c: remove unneeded variable: "ret"

remove unneeded variable: "ret"

Signed-off-by: zuoqilin <zuoqilin@yulong.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: max2175: fix max2175_set_csm_mode() error code

This is supposed to return negative error codes but the type is bool so
it returns true instead.

Fixes: b47b79d8a231 ("[media] media: i2c: max2175: Add MAX2175 support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: docs: add an uAPI chapter for driver-specific stuff

There are some uAPI stuff that are driver-specific. Add them
to the main media uAPI body.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: i2c: Use div64_ul() for u64-by-unsigned-long divide

div_u64() does a 64-by-32 division, while the divisor max2175.xtal_freq
is unsigned long, thus 64-bit on 64-bit platforms. Hence the proper
function to call is div64_ul().

Note that this change does not have any functional impact, as the
crystal frequency must be much lower than the 32-bit limit anyway.
On 32-bit platforms, the generated code is the same. But at least on
arm64, this saves an AND-instruction to truncate xtal_freq to 32-bit.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

media: i2c: Convert to new i2c device probe()

The I2C core framework provides a simplified probe framework from commit
b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new() call-back type").

These drivers do not utilise the i2c_device_id table in the probe, so we
can easily convert them to utilise the simplified i2c driver
registration.

Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Acked-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

media: i2c: max2175: convert to SPDX identifiers

This patch updates license to use SPDX-License-Identifier
instead of verbose license text.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Ramesh Shanmugasundaram <Ramesh.shanmugasundaram@bp.renesas.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

media: use strscpy() instead of strlcpy()

The implementation of strscpy() is more robust and safer.

That's now the recommended way to copy NUL terminated strings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

media: max2175: fix location of driver's companion documentation

There's a missing ".rst" at the doc's file name.

Acked-by: Ramesh Shanmugasundaram <Ramesh.shanmugasundaram@bp.renesas.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>

media: i2c: max2175: use 64-bit arithmetic instead of 32-bit

Add suffix LL to constant 2 in order to give the compiler complete
information about the proper arithmetic to use. Notice that this
constant is used in a context that expects an expression of type
s64 (64 bits, signed).

The expression 2 * (clock_rate - abs_nco_freq) is currently being
evaluated using 32-bit arithmetic.

Addresses-Coverity-ID: 1446589 ("Unintentional integer overflow")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

media: max2175: don't clear V4L2_SUBDEV_FL_IS_I2C

The v4l2_i2c_subdev_init() sets V4L2_SUBDEV_FL_IS_I2C flag in the
subdev->flags. But this driver overwrites subdev->flags immediately after
calling v4l2_i2c_subdev_init(). So V4L2_SUBDEV_FL_IS_I2C is not set after
all.

This stops breaking subdev->flags and preserves V4L2_SUBDEV_FL_IS_I2C.

Side note: According to the comment in v4l2_device_unregister(), this is
problematic only if the device is platform bus device. Device tree or
ACPI based devices are not affected.

Cc: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

media: max2175: Propagate the real error on devm_clk_get() failure

When devm_clk_get() fails we should return the real error code
instead of always returning -ENODEV.

This allows defer probe to happen in the case the clock provider has
not been enabled by the time max2175 driver gets probed.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

[media] max2175: remove an useless comparision

load is an unsigned integer. So, it is always bigger or equal
to zero, as reported by gcc:

drivers/media/i2c/max2175.c: In function 'max2175_refout_load_to_bits':
drivers/media/i2c/max2175.c:1272:11: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
if (load >= 0 && load <= 40)
^~

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

[media] media: i2c: max2175: Add MAX2175 support

This patch adds driver support for the MAX2175 chip. This is Maxim
Integrated's RF to Bits tuner front end chip designed for software-defined
radio solutions. This driver exposes the tuner as a sub-device instance
with standard and custom controls to configure the device.

Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>