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 mer

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

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drm/sun4i: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error han

drm/sun4i: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert the sun4i drm drivers from always returning zero in
the remove callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230507162616.1368908-44-u.kleine-koenig@pengutronix.de

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drm: sun4i_tcon: use devm_clk_get_enabled in `sun4i_tcon_init_clocks`

Smatch reports:
drivers/gpu/drm/sun4i/sun4i_tcon.c:805 sun4i_tcon_init_clocks() warn:
'tcon->clk' from clk_prepare_enable() not

drm: sun4i_tcon: use devm_clk_get_enabled in `sun4i_tcon_init_clocks`

Smatch reports:
drivers/gpu/drm/sun4i/sun4i_tcon.c:805 sun4i_tcon_init_clocks() warn:
'tcon->clk' from clk_prepare_enable() not released on lines: 792,801.

In the function sun4i_tcon_init_clocks(), tcon->clk and tcon->sclk0 are
not disabled in the error handling, which affects the release of
these variable. Although sun4i_tcon_bind(), which calls
sun4i_tcon_init_clocks(), use sun4i_tcon_free_clocks to disable the
variables mentioned, but the error handling branch of
sun4i_tcon_init_clocks() ignores the required disable process.

To fix this issue, use the devm_clk_get_enabled to automatically
balance enable and disabled calls. As original implementation use
sun4i_tcon_free_clocks() to disable clk explicitly, we delete the
related calls and error handling that are no longer needed.

Fixes: 9026e0d122ac ("drm: Add Allwinner A10 Display Engine support")
Fixes: b14e945bda8a ("drm/sun4i: tcon: Prepare and enable TCON channel 0 clock at init")
Fixes: 8e9240472522 ("drm/sun4i: support TCONs without channel 1")
Fixes: 34d698f6e349 ("drm/sun4i: Add has_channel_0 TCON quirk")
Signed-off-by: XuDong Liu <m202071377@hust.edu.cn>
Reviewed-by: Dongliang Mu <dzm91@hust.edu.cn>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20230430112347.4689-1-m202071377@hust.edu.cn

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drm: sun4i: calculate proper DCLK rate for DSI

In DSI mode, TCON0's data clock is required to run at 1/4 the per-lane
bit rate.

Signed-off-by: Roman Beranek <me@crly.cz>
Signed-off-by: Maxime Ripar

drm: sun4i: calculate proper DCLK rate for DSI

In DSI mode, TCON0's data clock is required to run at 1/4 the per-lane
bit rate.

Signed-off-by: Roman Beranek <me@crly.cz>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20230505052110.67514-5-me@crly.cz

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drm: sun4i: rename sun4i_dotclock to sun4i_tcon_dclk

While the rate of TCON0's DCLK matches dotclock for parallel and LVDS
outputs, this doesn't hold for DSI. The 'D' in DCLK actually stands for
'Da

drm: sun4i: rename sun4i_dotclock to sun4i_tcon_dclk

While the rate of TCON0's DCLK matches dotclock for parallel and LVDS
outputs, this doesn't hold for DSI. The 'D' in DCLK actually stands for
'Data' according to Allwinner's manuals. The clock is mostly referred to
as dclk throughout this driver already anyway, so stick with that.

Signed-off-by: Roman Beranek <me@crly.cz>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20230505052110.67514-4-me@crly.cz

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drm: Remove linux/media-bus-format.h from drm_crtc.h

drm_crtc.h has no need for linux/media-bus-format.h, so don't
include it. Avoids useless rebuilds of the entire universe when
touching linux/medi

drm: Remove linux/media-bus-format.h from drm_crtc.h

drm_crtc.h has no need for linux/media-bus-format.h, so don't
include it. Avoids useless rebuilds of the entire universe when
touching linux/media-bus-format.h.

Quite a few placs do currently depend on linux/media-bus-format.h
without actually including it directly. All of those need to be
fixed up.

v2: Deal with ingenic as well
v3: Fix up mxsfb and remaining parts of imx

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220630195114.17407-4-ville.syrjala@linux.intel.com

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drm/sun4i: Add support for D1 TCONs

D1 has a TCON TOP, so its quirks are similar to those for the R40 TCONs.
While there are some register changes, the part of the TCON TV supported
by the driver ma

drm/sun4i: Add support for D1 TCONs

D1 has a TCON TOP, so its quirks are similar to those for the R40 TCONs.
While there are some register changes, the part of the TCON TV supported
by the driver matches the R40 quirks, so that quirks structure can be
reused. D1 has the first supported TCON LCD with a TCON TOP, so the TCON
LCD needs a new quirks structure.

D1's TCON LCD hardware supports LVDS; in fact it provides dual-link LVDS
from a single TCON. However, it comes with a brand new LVDS PHY. Since
this PHY has not been tested, leave out LVDS driver support for now.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220424162633.12369-14-samuel@sholland.org

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drm/sun4i: Make use of the helper function devm_platform_ioremap_resource()

Use the devm_platform_ioremap_resource() helper instead of
calling platform_get_resource() and devm_ioremap_resource()
sep

drm/sun4i: Make use of the helper function devm_platform_ioremap_resource()

Use the devm_platform_ioremap_resource() helper instead of
calling platform_get_resource() and devm_ioremap_resource()
separately

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210831135740.4826-1-caihuoqing@baidu.com

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drm/sun4i: tcon: set sync polarity for tcon1 channel

Channel 1 has polarity bits for vsync and hsync signals but driver never
sets them. It turns out that with pre-HDMI2 controllers seemingly there

drm/sun4i: tcon: set sync polarity for tcon1 channel

Channel 1 has polarity bits for vsync and hsync signals but driver never
sets them. It turns out that with pre-HDMI2 controllers seemingly there
is no issue if polarity is not set. However, with HDMI2 controllers
(H6) there often comes to de-synchronization due to phase shift. This
causes flickering screen. It's safe to assume that similar issues might
happen also with pre-HDMI2 controllers.

Solve issue with setting vsync and hsync polarity. Note that display
stacks with tcon top have polarity bits actually in tcon0 polarity
register.

Fixes: 9026e0d122ac ("drm: Add Allwinner A10 Display Engine support")
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Tested-by: Andre Heider <a.heider@gmail.com>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210209175900.7092-3-jernej.skrabec@siol.net

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drm/sun4i: tcon: fix inverted DCLK polarity

During commit 88bc4178568b ("drm: Use new
DRM_BUS_FLAG_*_(DRIVE|SAMPLE)_(POS|NEG)EDGE flags") DRM_BUS_FLAG_*
macros have been changed to avoid ambiguity b

drm/sun4i: tcon: fix inverted DCLK polarity

During commit 88bc4178568b ("drm: Use new
DRM_BUS_FLAG_*_(DRIVE|SAMPLE)_(POS|NEG)EDGE flags") DRM_BUS_FLAG_*
macros have been changed to avoid ambiguity but just because of this
ambiguity previous DRM_BUS_FLAG_PIXDATA_(POS/NEG)EDGE were used meaning
_SAMPLE_ not _DRIVE_. This leads to DLCK inversion and need to fix but
instead of swapping phase values, let's adopt an easier approach Maxime
suggested:
It turned out that bit 26 of SUN4I_TCON0_IO_POL_REG is dedicated to
invert DCLK polarity and this makes things really easier than before. So
let's handle DCLK polarity by adding SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE
as bit 26 and activating according to bus_flags the same way it is done
for all the other signals polarity.

Fixes: 88bc4178568b ("drm: Use new DRM_BUS_FLAG_*_(DRIVE|SAMPLE)_(POS|NEG)EDGE flags")
Suggested-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210114081732.9386-1-giulio.benetti@benettiengineering.com

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drm/sun4i: tcon: fix inverted DCLK polarity

[ Upstream commit 67f4aeb2b41a0629abde3794d463547f60b0cbdd ]

During commit 88bc4178568b ("drm: Use new
DRM_BUS_FLAG_*_(DRIVE|SAMPLE)_(POS|NEG)EDGE flags"

drm/sun4i: tcon: fix inverted DCLK polarity

[ Upstream commit 67f4aeb2b41a0629abde3794d463547f60b0cbdd ]

During commit 88bc4178568b ("drm: Use new
DRM_BUS_FLAG_*_(DRIVE|SAMPLE)_(POS|NEG)EDGE flags") DRM_BUS_FLAG_*
macros have been changed to avoid ambiguity but just because of this
ambiguity previous DRM_BUS_FLAG_PIXDATA_(POS/NEG)EDGE were used meaning
_SAMPLE_ not _DRIVE_. This leads to DLCK inversion and need to fix but
instead of swapping phase values, let's adopt an easier approach Maxime
suggested:
It turned out that bit 26 of SUN4I_TCON0_IO_POL_REG is dedicated to
invert DCLK polarity and this makes things really easier than before. So
let's handle DCLK polarity by adding SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE
as bit 26 and activating according to bus_flags the same way it is done
for all the other signals polarity.

Fixes: 88bc4178568b ("drm: Use new DRM_BUS_FLAG_*_(DRIVE|SAMPLE)_(POS|NEG)EDGE flags")
Suggested-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210114081732.9386-1-giulio.benetti@benettiengineering.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

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drm/sun4i: tcon: set sync polarity for tcon1 channel

[ Upstream commit 50791f5d7b6a14b388f46c8885f71d1b98216d1d ]

Channel 1 has polarity bits for vsync and hsync signals but driver never
sets them.

drm/sun4i: tcon: set sync polarity for tcon1 channel

[ Upstream commit 50791f5d7b6a14b388f46c8885f71d1b98216d1d ]

Channel 1 has polarity bits for vsync and hsync signals but driver never
sets them. It turns out that with pre-HDMI2 controllers seemingly there
is no issue if polarity is not set. However, with HDMI2 controllers
(H6) there often comes to de-synchronization due to phase shift. This
causes flickering screen. It's safe to assume that similar issues might
happen also with pre-HDMI2 controllers.

Solve issue with setting vsync and hsync polarity. Note that display
stacks with tcon top have polarity bits actually in tcon0 polarity
register.

Fixes: 9026e0d122ac ("drm: Add Allwinner A10 Display Engine support")
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Tested-by: Andre Heider <a.heider@gmail.com>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210209175900.7092-3-jernej.skrabec@siol.net
Signed-off-by: Sasha Levin <sashal@kernel.org>

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drm/sun4i: add missing put_device() call in sun8i_r40_tcon_tv_set_mux()

If sun8i_r40_tcon_tv_set_mux() succeed, sun8i_r40_tcon_tv_set_mux()
doesn't have a corresponding put_device(). Thus add put_de

drm/sun4i: add missing put_device() call in sun8i_r40_tcon_tv_set_mux()

If sun8i_r40_tcon_tv_set_mux() succeed, sun8i_r40_tcon_tv_set_mux()
doesn't have a corresponding put_device(). Thus add put_device()
to fix the exception handling for this function implementation.

Fixes: 0305189afb32 ("drm/sun4i: tcon: Add support for R40 TCON")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200826010826.1785487-1-yukuai3@huawei.com

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drm/sun4i: lvds: Invert the LVDS polarity

The LVDS controller can invert the polarity / lanes of the LVDS output.
The default polarity causes some issues on some panels.

However, U-Boot has always

drm/sun4i: lvds: Invert the LVDS polarity

The LVDS controller can invert the polarity / lanes of the LVDS output.
The default polarity causes some issues on some panels.

However, U-Boot has always used the opposite polarity without any reported
issue, and the only currently supported LVDS panel in-tree (the TBS A711)
seems to be able to work with both settings.

Let's just use the same polarity than U-Boot to be more consistent and
hopefully support all the panels.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Cc: Ondrej Jirman <megous@megous.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200704133803.37330-1-maxime@cerno.tech

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treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through mar

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

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drm/sun4i: Constify static structs

A number of static variables are not modified and can be made const to
allow the compiler to put them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard

drm/sun4i: Constify static structs

A number of static variables are not modified and can be made const to
allow the compiler to put them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200804215337.54594-1-rikard.falkeborn@gmail.com

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drm/sun4i: tcon: Delete an error message in sun4i_tcon_init_irq()

The function “platform_get_irq” can log an error already.
Thus omit a redundant message for the exception handling in the
calling fu

drm/sun4i: tcon: Delete an error message in sun4i_tcon_init_irq()

The function “platform_get_irq” can log an error already.
Thus omit a redundant message for the exception handling in the
calling function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/5a6cf5a7-3f27-5425-4d6a-550a17bc51e3@web.de

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drm/sun4i: tcon: Support LVDS on the A33

The A33 TCON supports LVDS, so we can toggle the support switch.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Lin

drm/sun4i: tcon: Support LVDS on the A33

The A33 TCON supports LVDS, so we can toggle the support switch.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200214120934.107924-1-maxime@cerno.tech

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drm/sun4i: tcon: Support LVDS output on Allwinner A20

A20 SoC (found in Cubieboard 2 among others) requires different LVDS set
up procedure than A33. Timing controller (tcon) driver only implements

drm/sun4i: tcon: Support LVDS output on Allwinner A20

A20 SoC (found in Cubieboard 2 among others) requires different LVDS set
up procedure than A33. Timing controller (tcon) driver only implements
sun6i-style procedure, that doesn't work on A20 (sun7i).

Signed-off-by: Andrey Lebedev <andrey@lebedev.lt>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200219180858.4806-6-andrey.lebedev@gmail.com

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drm/sun4i: tcon: Separate quirks for tcon0 and tcon1 on A20

Timing controllers on A20 are not equivalent: tcon0 on A20 supports
LVDS output and tcon1 does not. Separate the capabilities by
introduci

drm/sun4i: tcon: Separate quirks for tcon0 and tcon1 on A20

Timing controllers on A20 are not equivalent: tcon0 on A20 supports
LVDS output and tcon1 does not. Separate the capabilities by
introducing independent set of quirks for each of the tcons.

Signed-off-by: Andrey Lebedev <andrey@lebedev.lt>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200219180858.4806-3-andrey.lebedev@gmail.com

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drm/sun4i: tcon: Introduce LVDS setup routine setting

Different sunxi flavors require slightly different sequence for enabling
LVDS output. This allows to differentiate between them.

Signed-off-by:

drm/sun4i: tcon: Introduce LVDS setup routine setting

Different sunxi flavors require slightly different sequence for enabling
LVDS output. This allows to differentiate between them.

Signed-off-by: Andrey Lebedev <andrey@lebedev.lt>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200219180858.4806-2-andrey.lebedev@gmail.com

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drm/sun4i: tcon: Set RGB DCLK min. divider based on hardware model

In commit 0b8e7bbde5e7 ("drm/sun4i: tcon: Set min division of TCON0_DCLK
to 1.") it was assumed that all TCON variants support a mi

drm/sun4i: tcon: Set RGB DCLK min. divider based on hardware model

In commit 0b8e7bbde5e7 ("drm/sun4i: tcon: Set min division of TCON0_DCLK
to 1.") it was assumed that all TCON variants support a minimum divider
of 1 if only DCLK was used.

However, the oldest generation of hardware only supports minimum divider
of 4 if only DCLK is used. If a divider of 1 was used on this old
hardware, some scrolling artifact would appear. A divider of 2 seemed
OK, but a divider of 3 had artifacts as well.

Set the minimum divider when outputing to parallel RGB based on the
hardware model, with a minimum of 4 for the oldest (A10/A10s/A13/A20)
hardware, and a minimum of 1 for the rest. A value is not set for the
TCON variants lacking channel 0.

This fixes the scrolling artifacts seen on my A13 tablet.

Fixes: 0b8e7bbde5e7 ("drm/sun4i: tcon: Set min division of TCON0_DCLK to 1.")
Cc: <stable@vger.kernel.org> # 5.4.x
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200107070113.28951-1-wens@kernel.org

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drm/sun4i: tcon: Set min division of TCON0_DCLK to 1.

The datasheet of V3s (and various other chips) wrote
that TCON0_DCLK_DIV can be >= 1 if only dclk is used,
and must >= 6 if dclk1 or dclk2 is us

drm/sun4i: tcon: Set min division of TCON0_DCLK to 1.

The datasheet of V3s (and various other chips) wrote
that TCON0_DCLK_DIV can be >= 1 if only dclk is used,
and must >= 6 if dclk1 or dclk2 is used. As currently
neither dclk1 nor dclk2 is used (no writes to these
bits), let's set minimal division to 1.

If this minimal division is 6, some common dot clock
frequencies can't be produced (e.g. 30MHz will not be
possible and will fallback to 25MHz), which is
obviously not an expected behaviour.

Signed-off-by: Yunhao Tian <t123yh@outlook.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/linux-arm-kernel/MN2PR08MB57905AD8A00C08DA219377C989760@MN2PR08MB5790.namprd08.prod.outlook.com/

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drm: Stop including drm_bridge.h from drm_crtc.h

We are about to add a drm_bridge_state that inherits from
drm_private_state which is defined in drm_atomic.h. Problem is,
drm_atomic.h includes drm_c

drm: Stop including drm_bridge.h from drm_crtc.h

We are about to add a drm_bridge_state that inherits from
drm_private_state which is defined in drm_atomic.h. Problem is,
drm_atomic.h includes drm_crtc.h which in turn includes drm_bridge.h,
leading to "drm_private_state has incomplete type" error.

Let's force all users of the drm_bridge API to explicitly include
drm_bridge.h.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190826152649.13820-2-boris.brezillon@collabora.com

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drm/sun4i: tcon: Mark expected switch fall-through

Mark switch cases where we are expecting to fall through.

Fix the following warning (Building: sunxi_defconfig arm):

drivers/gpu/drm/sun4i/sun4i_

drm/sun4i: tcon: Mark expected switch fall-through

Mark switch cases where we are expecting to fall through.

Fix the following warning (Building: sunxi_defconfig arm):

drivers/gpu/drm/sun4i/sun4i_tcon.c: In function ‘sun4i_tcon0_mode_set_dithering’:
drivers/gpu/drm/sun4i/sun4i_tcon.c:318:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
val |= SUN4I_TCON0_FRM_CTL_MODE_B;
drivers/gpu/drm/sun4i/sun4i_tcon.c:319:2: note: here
case MEDIA_BUS_FMT_RGB666_1X18:
^~~~

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

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