drm: mipi-dsi: make mipi_dsi_bus_type const

Now that the driver core can properly handle constant struct bus_type,
move the mipi_dsi_bus_type variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240203-bus_cleanup-gpu-v1-2-1b6ecdb5f941@marliere.net
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240203-bus_cleanup-gpu-v1-2-1b6ecdb5f941@marliere.net

drm/mipi-dsi: Fix detach call without attach

It's been reported that DSI host driver's detach can be called without
the attach ever happening:

https://lore.kernel.org/all/20230412073954.20601-1-tony@atomide.com/

After reading the code, I think this is what happens:

We have a DSI host defined in the device tree and a DSI peripheral under
that host (i.e. an i2c device using the DSI as data bus doesn't exhibit
this behavior).

The host driver calls mipi_dsi_host_register(), which causes (via a few
functions) mipi_dsi_device_add() to be called for the DSI peripheral. So
now we have a DSI device under the host, but attach hasn't been called.

Normally the probing of the devices continues, and eventually the DSI
peripheral's driver will call mipi_dsi_attach(), attaching the
peripheral.

However, if the host driver's probe encounters an error after calling
mipi_dsi_host_register(), and before the peripheral has called
mipi_dsi_attach(), the host driver will do cleanups and return an error
from its probe function. The cleanups include calling
mipi_dsi_host_unregister().

mipi_dsi_host_unregister() will call two functions for all its DSI
peripheral devices: mipi_dsi_detach() and mipi_dsi_device_unregister().
The latter makes sense, as the device exists, but the former may be
wrong as attach has not necessarily been done.

To fix this, track the attached state of the peripheral, and only detach
from mipi_dsi_host_unregister() if the peripheral was attached.

Note that I have only tested this with a board with an i2c DSI
peripheral, not with a "pure" DSI peripheral.

However, slightly related, the unregister machinery still seems broken.
E.g. if the DSI host driver is unbound, it'll detach and unregister the
DSI peripherals. After that, when the DSI peripheral driver unbound
it'll call detach either directly or using the devm variant, leading to
a crash. And probably the driver will crash if it happens, for some
reason, to try to send a message via the DSI bus.

But that's another topic.

Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230921-dsi-detach-fix-v1-1-d0de2d1621d9@ideasonboard.com

drm: 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: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Acked-by: Robert Foss <rfoss@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230714174545.4056287-1-robh@kernel.org

drm/display/dp_mst: Replace all non-returning strlcpy with strscpy

strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230522155124.2336545-1-azeemshaikh38@gmail.com

drm/mipi-dsi: Set the fwnode for mipi_dsi_device

After commit 3fb16866b51d ("driver core: fw_devlink: Make cycle
detection more robust"), fw_devlink prints an error when consumer
devices don't have their fwnode set. This used to be ignored silently.

Set the fwnode mipi_dsi_device so fw_devlink can find them and properly
track their dependencies.

This fixes errors like this:
[ 0.334054] nwl-dsi 30a00000.mipi-dsi: Failed to create device link with regulator-lcd-1v8
[ 0.346964] nwl-dsi 30a00000.mipi-dsi: Failed to create device link with backlight-dsi

Reported-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Link: https://lore.kernel.org/lkml/2a8e407f4f18c9350f8629a2b5fa18673355b2ae.camel@puri.sm/
Fixes: 068a00233969 ("drm: Add MIPI DSI bus support")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Link: https://lore.kernel.org/r/20230310063910.2474472-1-saravanak@google.com
Signed-off-by: Maxime Ripard <maxime@cerno.tech>

of: Rename of_modalias_node()

This helper does not produce a real modalias, but tries to get the
"product" compatible part of the "vendor,product" compatibles only. It
is far from creating a purely useful modalias string and does not seem
to be used like that directly anyway, so let's try to give this helper a
more meaningful name before moving there a real modalias helper (already
existing under of/device.c).

Also update the various documentations to refer to the strings as
"aliases" rather than "modaliases" which has a real meaning in the Linux
kernel.

There is no functional change.

Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Wolfram Sang <wsa@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Sebastian Reichel <sre@kernel.org>
Link: https://lore.kernel.org/r/20230404172148.82422-9-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm: Use of_property_present() for testing DT property presence

It is preferred to use typed property access functions (i.e.
of_property_read_<type> functions) rather than low-level
of_get_property/of_find_property functions for reading properties. As
part of this, convert of_get_property/of_find_property calls to the
recently added of_property_present() helper when we just want to test
for presence of a property and nothing more.

Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Reviewed-by: Liu Ying <victor.liu@nxp.com> # i.MX bridge
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://lore.kernel.org/r/20230310144705.1542207-1-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>

driver core: make struct bus_type.uevent() take a const *

The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm/mipi-dsi: Fix byte order of 16-bit DCS set/get brightness

The MIPI DCS specification demands that brightness values are sent in
big endian byte order. It also states that one parameter (i.e. one byte)
shall be sent/received for 8 bit wide values, and two parameters shall
be used for values that are between 9 and 16 bits wide.

Add new functions to properly handle 16-bit brightness in big endian,
since the two 8- and 16-bit cases are distinct from each other.

[richard: use separate functions instead of switch/case]
[richard: split into 16-bit component]

Fixes: 1a9d759331b8 ("drm/dsi: Implement DCS set/get display brightness")
Signed-off-by: Daniel Mentz <danielmentz@google.com>
Link: https://android.googlesource.com/kernel/msm/+/754affd62d0ee268c686c53169b1dbb7deac8550
[richard: fix 16-bit brightness_get]
Signed-off-by: Richard Acayan <mailingradian@gmail.com>
Tested-by: Caleb Connolly <caleb@connolly.tech>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230116224909.23884-2-mailingradian@gmail.com

gpu/drm: fix repeated words in comments

Delete the redundant word 'the'.

Signed-off-by: wangjianli <wangjianli@cdjrlc.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20221022060551.56918-1-wangjianli@cdjrlc.com

drm/mipi-dsi: Detach devices when removing the host

Whenever the MIPI-DSI host is unregistered, the code of
mipi_dsi_host_unregister() loops over every device currently found on that
bus and will unregister it.

However, it doesn't detach it from the bus first, which leads to all kind
of resource leaks if the host wants to perform some clean up whenever a
device is detached.

Fixes: 068a00233969 ("drm: Add MIPI DSI bus support")
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-2-maxime@cerno.tech

drm/mipi-dsi: Make remove callback return void

All implementations return 0 and the return value of mipi_dsi_drv_remove()
is ignored anyhow.

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.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220708094922.1408248-4-u.kleine-koenig@pengutronix.de

drm/display: Move DSC header and helpers into display-helper module

DSC is the Display Stream Compression standard for DisplayPort. Move
the DSC code into display/ and split the header into files for protocol
core and DRM helpers. Adapt all users of the code. No functional
changes.

To avoid the proliferation of Kconfig options, DSC is part of DRM's
support for DisplayPort. If necessary, a new option could make DSC an
independent feature.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220421073108.19226-6-tzimmermann@suse.de

drm/mipi-dsi: Create devm device attachment

MIPI-DSI devices need to call mipi_dsi_attach() when their probe is done
to attach against their host.

However, at removal or when an error occurs, that attachment needs to be
undone through a call to mipi_dsi_detach().

Let's create a device-managed variant of the attachment function that
will automatically detach the device at unbind.

Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210910101218.1632297-5-maxime@cerno.tech

drm/mipi-dsi: Create devm device registration

Devices that take their data through the MIPI-DSI bus but are controlled
through a secondary bus like I2C have to register a secondary device on
the MIPI-DSI bus through the mipi_dsi_device_register_full() function.

At removal or when an error occurs, that device needs to be removed
through a call to mipi_dsi_device_unregister().

Let's create a device-managed variant of the registration function that
will automatically unregister the device at unbind.

Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210910101218.1632297-4-maxime@cerno.tech

drm: mipi-dsi: Convert logging to drm_* functions.

Convert logging errors from dev_err() to drm_err().

Signed-off-by: Suraj Upadhyay <usuraj35@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/feeec2816debcf4105ac22af1661fd2d491d02b9.1594136880.git.usuraj35@gmail.com

drm/mipi: use dcs write for mipi_dsi_dcs_set_tear_scanline

The helper uses the MIPI_DCS_SET_TEAR_SCANLINE, although it's currently
using the generic write. This does not look right.

Perhaps some platforms don't distinguish between the two writers?

Cc: Robert Chiras <robert.chiras@nxp.com>
Cc: Vinay Simha BN <simhavcs@gmail.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Thierry Reding <treding@nvidia.com>
Fixes: e83950816367 ("drm/dsi: Implement set tear scanline")
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200505160329.2976059-3-emil.l.velikov@gmail.com

drm/dsi: use stack buffer in mipi_dsi_dcs_write()

Currently the function heap allocates when we have any payload. Where in
many case the payload is 1 byte - ouch.

>From casual observation, vast majority of the payloads are smaller than
8 bytes - so use a stack array tx[8] to avoid the senseless kmalloc and
kfree dance.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Thierry Reding <treding@nvidia.com>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200505160329.2976059-1-emil.l.velikov@gmail.com

drm/dsi: add helpers for DSI compression mode and PPS packets

Add helper functions for sending the DSI compression mode and picture
parameter set data type packets. For the time being, limit the support
to using VESA DSC 1.1 and the default PPS. This may need updating if the
need arises for proprietary compression or non-default PPS, however keep
it simple for starters.

v2: Add missing EXPORT_SYMBOL

Cc: Vandita Kulkarni <vandita.kulkarni@intel.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191028150047.22048-5-jani.nikula@intel.com

drm/dsi: add missing DSI data types

Add execute queue and compressed pixel stream packet data types for
completeness.

Cc: Vandita Kulkarni <vandita.kulkarni@intel.com>
Reviewed-by: Vandita Kulkarni <vandita.kulkarni@intel.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191028150047.22048-2-jani.nikula@intel.com

drm/dsi: clean up DSI data type definitions

Rename picture parameter set (it's a long packet, not a long write) and
compression mode (it's not a DCS command) enumerations according to the
DSI specification. Order the types according to the spec. Use tabs
instead of spaces for indentation. Use all lower case for hex.

Cc: Vandita Kulkarni <vandita.kulkarni@intel.com>
Reviewed-by: Vandita Kulkarni <vandita.kulkarni@intel.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191028150047.22048-1-jani.nikula@intel.com

drivers: Introduce device lookup variants by of_node

Introduce wrappers for {bus/driver/class}_find_device() to
locate devices by its of_node.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: dri-devel@lists.freedesktop.org
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: devicetree@vger.kernel.org
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: linux-i2c@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-spi@vger.kernel.org
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Alan Tull <atull@kernel.org>
Cc: linux-fpga@vger.kernel.org
Cc: Peter Rosin <peda@axentia.se>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Thor Thayer <thor.thayer@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Peter Rosin <peda@axentia.se>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de> # I2C part
Acked-by: Moritz Fischer <mdf@kernel.org> # For FPGA part
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20190723221838.12024-3-suzuki.poulose@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

bus_find_device: Unify the match callback with class_find_device

There is an arbitrary difference between the prototypes of
bus_find_device() and class_find_device() preventing their callers
from passing the same pair of data and match() arguments to both of
them, which is the const qualifier used in the prototype of
class_find_device(). If that qualifier is also used in the
bus_find_device() prototype, it will be possible to pass the same
match() callback function to both bus_find_device() and
class_find_device(), which will allow some optimizations to be made in
order to avoid code duplication going forward. Also with that, constify
the "data" parameter as it is passed as a const to the match function.

For this reason, change the prototype of bus_find_device() to match
the prototype of class_find_device() and adjust its callers to use the
const qualifier in accordance with the new prototype of it.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Andreas Noever <andreas.noever@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Corey Minyard <minyard@acm.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Kershner <david.kershner@unisys.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Airlie <airlied@linux.ie>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Jamet <michael.jamet@intel.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: Sebastian Ott <sebott@linux.ibm.com>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Yehezkel Bernat <YehezkelShB@gmail.com>
Cc: rafael@kernel.org
Acked-by: Corey Minyard <minyard@acm.org>
Acked-by: David Kershner <david.kershner@unisys.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de> # for the I2C parts
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm: Add support for pps and compression mode command packet

After enabling DSC we need to send compression mode command packet
and pps data packet, for which 2 new data types are added
07h Compression Mode Data Type Write , short write, 2 parameters
0Ah PPS Long Write (word count determines number of bytes)
This patch adds support to send these packets.

Cc: David Airlie <airlied@linux.ie>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-fbdev@vger.kernel.org

Changes in v3:
- None

Signed-off-by: vkorjani <vikas.korjani@intel.com>
[seanpaul removed pps_write_buffer fn, added types to packet_format helpers]
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drm/dsi: Fix improper use of mipi_dsi_device_transfer() return value

The function mipi_dsi_device_transfer() returns the number of transmitted
or received bytes on success or a negative error code on failure.

The functions mipi_dsi_shutdown_peripheral(), mipi_dsi_turn_on_peripheral() &
mipi_dsi_set_maximum_return_packet_size() use improperly this returned
value in case of success: 0 should be returned instead of the number of
transmitted bytes.

Signed-off-by: Philippe Cornu <philippe.cornu@st.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180112144847.18810-1-philippe.cornu@st.com

drm: Convert to using %pOF instead of full_name

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Javier Martinez Canillas <javier@osg.samsung.com>
Cc: Xinliang Liu <z.liuxinliang@hisilicon.com>
Cc: Rongrong Zou <zourongrong@gmail.com>
Cc: Xinwei Kong <kong.kongxinwei@hisilicon.com>
Cc: Chen Feng <puck.chen@hisilicon.com>
Cc: CK Hu <ck.hu@mediatek.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Mark Yao <mark.yao@rock-chips.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org
Partially-Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
[seanpaul changed subject prefix and fixed conflict in stm/ltdc.c]
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/dsi: Implement DCS set/get display brightness

Provide a small convenience wrapper that set/get the display brightness.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Archit Taneja <archit.taneja@gmail.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Vinay Simha BN <simhavcs@gmail.com>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Order DCS helpers by command code

Most of these helpers had been introduced in the correct order, but some
were simply appended, which wasn't detected when they were applied.

Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Make set_tear_scanline command consistent

Use a consistent name for the function that implements set_tear_scanline
and reword and reformat the kerneldoc slightly.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20160613133327.7630-1-thierry.reding@gmail.com

drm/dsi: Add uevent callback

Implement a uevent callback for devices on the MIPI DSI bus. This
callback will append MODALIAS information to the uevent and allow
modules to be loaded when devices are added to the bus.

Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Implement set tear scanline

Provide a small convenience wrapper that transmits
a set_tear_scanline command.

v2:
* helper function suggested by Thierry
for set_tear_scanline
* Also includes small build fixes from Sumit Semwal.

v3: one scanline parameter suggested by jani

v4: passing the payload properly as suggested by jani

Cc: Archit Taneja <archit.taneja@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Vinay Simha BN <simhavcs@gmail.com>
Reviewed-by: Sumit Semwal <sumit.semwal@linaro.org>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1465285532-12676-1-git-send-email-simhavcs@gmail.com

drm/dsi: Get DSI host by DT device node

MIPI DSI devices are inherently aware of their host because they share a
parent-child hierarchy in the device tree.

Non-DSI drivers that create DSI device don't have this data. In order to
get this information, they require to a phandle to the DSI host in the
device tree.

Maintain a list of all the DSI hosts that are currently registered. This
list will be used to find the struct mipi_dsi_host corresponding to the
device tree node passed to of_find_mipi_dsi_host_by_node().

Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Add routine to unregister a DSI device

A driver calling mipi_dsi_device_register_full() might want to remove
the device once it's done. It might also require it in an error handling
path in case something went wrong.

Create mipi_dsi_device_unregister() for this purpose and use it within
mipi_dsi_remove_device_fn() as it does the same thing.

Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Try to match non-DT DSI devices

Add a device name field in struct mipi_dsi_device. This name is not the
same as the device name (which is of the format "hostname.reg"). When
the device is created via DT, this name is set to the modalias string.
In the non-DT case, the driver creating the DSI device provides the
name by populating a field in struct mipi_dsi_device_info.

Matching for DT case would be as it was before. For the non-DT case, we
compare the device and driver names. Other buses (like I2C/SPI) perform
a non-DT match by comparing the device name and entries in the driver's
id_table. Such a mechanism isn't used for the DSI bus.

Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Use mipi_dsi_device_register_full() for DSI device creation

Use mipi_dsi_device_register_full() for device creation. This takes in
a struct mipi_dsi_device_info as a template to populate the DSI device
information.

The reason to introduce this is to have a way to create DSI devices not
available via DT. Drivers that want to create a DSI device can populate
a struct mipi_dsi_device_info and call this function. For DSI devices
available via DT, of_mipi_dsi_device_add() is used as before, but this
now calls mipi_dsi_device_register_full() internally.

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Check for CONFIG_OF when defining of_mipi_dsi_device_add()

of_mipi_dsi_device_add() is used only when CONFIG_OF is enabled. It
currently works if OF support is disabled, but this will change when we
add more functionality to it.

Define the original function if CONFIG_OF is enabled and a dummy
function otherwise.

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Add Turn On/Shutdown Peripheral command helpers

The MIPI_DSI_TURN_ON_PERIPHERAL and MIPI_DSI_SHUTDOWN_PERIPHERAL packets
are required for some panels, for example the Panasonic VVX10F034N00.

Signed-off-by: Werner Johansson <werner.johansson@sonymobile.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/mipi-dsi: Avoid potential NULL pointer dereference

The mipi_dsi_packet_create() function dereferences the msg pointer
before checking that it's valid. Move the dereference down to where it
is required to avoid potentially dereferencing a NULL pointer.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Do not require .owner field to be set

Drivers now no longer need to set the .owner field. It will be
automatically set at registration time.

Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Resolve MIPI DSI device from phandle

Add a function, of_find_mipi_dsi_device_by_node(), that can be used to
resolve a phandle to a MIPI DSI device.

Acked-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Implement DCS set_{column,page}_address commands

Provide small convenience wrappers to set the column and page extents of
the frame memory accessed by the host processors.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Implement DCS {get,set}_pixel_format commands

Provide small convenience wrappers to query or set the pixel format used
by the interface.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Implement DCS get_power_mode command

Provide a small convenience wrapper that transmits a DCS get_power_mode
command. A set of bitmasks for the mode bits is also provided.

Acked-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Implement DCS soft_reset command

Provide a small convenience wrapper that transmits a DCS soft_reset
command.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Implement DCS nop command

Provide a small convenience wrapper that transmits a DCS nop command.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Add to DocBook documentation

Integrate the MIPI DSI helpers into DocBook and clean up various
kerneldoc warnings. Also add a brief DOC section and clarify some
aspects of the mipi_dsi_host struct's .transfer() operation.

Acked-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Implement some standard DCS commands

Add helpers for the {enter,exit}_sleep_mode, set_display_{on,off} and
set_tear_{on,off} DCS commands.

Signed-off-by: YoungJun Cho <yj44.cho@samsung.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
[treding: kerneldoc and other minor cleanup]
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Implement generic read and write commands

Implement generic read and write commands. Selection of the proper data
type for packets is done automatically based on the number of parameters
or payload length.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Add mipi_dsi_set_maximum_return_packet_size() helper

This function can be used to set the maximum return packet size for a
MIPI DSI peripheral.

Signed-off-by: YoungJun Cho <yj44.cho@samsung.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
[treding: endianess, kerneldoc, return value]
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Make mipi_dsi_dcs_{read,write}() symmetrical

Currently the mipi_dsi_dcs_write() function requires the DCS command
byte to be embedded within the write buffer whereas mipi_dsi_dcs_read()
has a separate parameter. Make them more symmetrical by adding an extra
command parameter to mipi_dsi_dcs_write().

The S6E8AA0 driver relies on the old asymmetric API and there's concern
that moving to the new API may be less efficient. Provide a new function
with the old semantics for those cases and make the S6E8AA0 driver use
it instead.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Add DSI transfer helper

A common pattern is starting to emerge for higher level transfer
helpers. Create a new helper that encapsulates this pattern and avoids
code duplication.

Acked-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Add message to packet translator

This commit introduces a new function, mipi_dsi_create_packet(), which
converts from a MIPI DSI message to a MIPI DSI packet. The MIPI DSI
packet is as close to the protocol described in the DSI specification as
possible and useful in drivers that need to write a DSI packet into a
FIFO to send a message off to the peripheral.

Suggested-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Introduce packet format helpers

Add two helpers, mipi_dsi_packet_format_is_{short,long}(), that help in
determining the format of a packet.

Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/mipi-dsi: consider low power transmission

This patch adds a new flag, MIPI_DSI-MODE_LPM, to transmit data
in low power. With this flag, msg.flags has MIPI_DSI_MSG_USE_LPM
so that host driver of each SoC can clear or set relevant register
bit for low power transmission.

All host drivers shall support continuous clock behavior on the
Clock Lane, and optionally may support non-continuous clock behavior.
Both of them can transmit data in high speed of low power.

With each clock behavior, non-continuous or continuous clock mode,
host controller will transmit data in high speed by default so if
peripheral wants to receive data in low power, the peripheral driver
should set MIPI_DSI_MODE_LPM flag.

Signed-off-by: Inki Dae <inki.dae@samsung.com>

drm/dsi: Use peripheral's channel for DCS commands

When executing DCS commands, use the channel associated with the DSI
peripheral rather than one explicitly specified in the function call.
Devices shouldn't be able to step on each others' toes like this.

Acked-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Make mipi_dsi_dcs_write() return ssize_t

This function returns the value of the struct mipi_dsi_host_ops'
.transfer() so make sure the return types are consistent.

Acked-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/dsi: Support device shutdown

Hook up the MIPI DSI bus's .shutdown() function to allow drivers to
implement code that should be run when a device is shut down.

Signed-off-by: Thierry Reding <treding@nvidia.com>

drm/mipi_dsi: create dsi devices only for nodes with reg property

MIPI DSI host node can contain child nodes which are not DSI devices.
Checking for existence of reg property can be used to distinguish such nodes.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drm: Add MIPI DSI bus support

MIPI DSI bus allows to model DSI hosts and DSI peripherals using the
Linux driver model. DSI hosts are registered by the DSI host drivers.
During registration DSI peripherals will be created from the children
of the DSI host's device tree node. Support for registration from
board-setup code will be added later when needed.

DSI hosts expose operations which can be used by DSI peripheral drivers
to access associated devices.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>