drm: renesas: shmobile: Add DT support

Add DT support, by:
1. Creating a panel bridge from DT, and attaching it to the encoder,
2. Replacing the custom connector with a bridge connector,
3. Obtaining clock configuration based on the compatible value.

Note that for now the driver uses a fixed clock configuration selecting
the bus clock, as the current code to select other clock inputs needs
changes to support any other SoCs than SH7724.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/6185ab76aa300fa402e4f6610b2109665f2d8a1c.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Atomic conversion part 3

Complete the conversion to atomic mode setting by converting the
connector, and setting the DRIVER_ATOMIC flag.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/042f9ff076c4b1c87235c74c8b76c9d161e126ec.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Use suspend/resume helpers

Replace the custom suspend/resume handling by calls into
drm_mode_config_helper_{suspend,resume}().

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/a52147ca6033e0a59675f37f0326c7404fc5919c.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Atomic conversion part 1

Implement atomic mode setting for both the primary and overlay planes.
This involves:
- Moving the primary plane handling code from CRTC mode setting to
plane handling shared by primary and overlay planes,
- Adding basic CRTC and mode config atomic mode setting ops, which
don't do much yet.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/a6b698a1c8c1eaf631c2f928f5888ab5fe7aa4c3.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Shutdown the display on remove

When the device is unbound from the driver, the display may be active.
Make sure it gets shut down.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/ddf2736459d59d0e961f240e77da7b0a28caae15.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Turn vblank on/off when enabling/disabling CRTC

The DRM core vblank handling mechanism requires drivers to forcefully
turn vblank reporting off when disabling the CRTC, and to restore the
vblank reporting status when enabling the CRTC.
Implement this using the drm_crtc_vblank_{on,off}() helpers.

Note that drm_crtc_vblank_off() must be called at startup to synchronize
the state of the vblank core code with the hardware, which is initially
disabled. This is performed at CRTC creation time, requiring vertical
blank initialization to be moved before creating CRTCs.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/e5833e5706b7792bfca8e6e56fc154a7c3e0574f.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Use drm_crtc_handle_vblank()

Replace the call to the legacy drm_handle_vblank() function with a call
to the new drm_crtc_handle_vblank() helper.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Sui Jingfeng <suijingfeng@loongson.cn>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/bef278cc9b7536505f41faaa2f13184d9354fa7e.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Unify plane allocation

Unify primary and overlay plane allocation:
- Enhance shmob_drm_plane_create() so it can be used to create the
primary plane, too,
- Move overlay plane creation next to primary plane creation.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/adbc5febc0099fd1910f32a7af1c8e0f570f74b4.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Move interface handling to connector setup

Move legacy interface handling to the connector setup code.
Set up bus_flags and bus_formats in display_info according to the
bus format and panel information from platform data, to make it more
similar with DT-based connector/bridge/panel setup.
This will allow us to use the same LCD interface setup code for both
legacy and DT-based systems.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/912f615eb87c847804a268200ab57c63453c65d4.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Use media bus formats in platform data

Replace the custom shmob_drm_interface enumeration values with standard
media bus formats. This simplifies driver handling of bus formats and
prepares for DT support.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/0a15e5100ca30d14953c93550eb1d4c2e18de939.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Replace .dev_private with container_of()

Now that drm_device is embedded in shmob_drm_device, we can use
a container_of()-based helper to get the shmob_drm_device pointer from
the drm_device, instead of using the deprecated drm_device.dev_private
field.

While at it, restore reverse Xmas tree ordering of local variable
declarations.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Sui Jingfeng <suijingfeng@loongson.cn>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/8ef4be8bffe75efc7f4b66f3732ec357f7d43e0f.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Embed drm_device in shmob_drm_device

Embedding drm_device in shmob_drm_device allows us to use the DRM
managed API to allocate both structures in one go, simplifying error
handling.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/abbf95021191824f44cc8c52e4afbde93d44363a.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Convert to use devm_request_irq()

Convert to managed IRQ handling, to simplify cleanup.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/8d870bdc59dd5e2754542388a03095ea09c96297.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Improve error handling

Prepare for DT conversion, where panel probe can be deferred, by
streamlining error propagation and handling:
- Use dev_err_probe() to avoid printing error messages in case of
probe deferral,
- Propagate errors where needed.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/6dfac76e5b1c7dda3f96801ce83845a4235e2ccd.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Remove support for SYS panels

SYS panels are not used, and have no defined DT bindings. Remove their
support to avoid impeding DT support. It can always be added back
later.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/4ccca2a5ac05c73ea9fd6e44b8bc443fd9d14e0d.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Rename input clocks

Prepare for DT bindings by using more appropriate names for the input
clocks.

Note that all LDDCKR_ICKSEL_* definitions but the one for the bus clock
are valid only for SH7724, so the clock selection code needs to be
updated when extending clock support to other SoCs.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
[geert: Add note]
Reviewed-by: Sui Jingfeng <suijingfeng@loongson.cn>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/d4b4d2164541ae055d10064103db3c2d6540e846.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Restore indentation of shmob_drm_setup_clocks()

Commit 56550d94cbaeaa19 ("Drivers: gpu: remove __dev* attributes.")
forgot to realign the continuation of the parameter section of
shmob_drm_setup_clocks().

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/b1c5c9b33b74fef1f4250847398a98f93c4dc1be.1694767209.git.geert+renesas@glider.be

drm: renesas: shmobile: Add support for Runtime PM

The SH-Mobile LCD Controller is part of a PM Domain on all relevant SoCs
(clock domain on all, power domain on some). Hence it may not be
sufficient to manage the LCDC module clock explicitly (e.g. if the
selected clock source differs from SHMOB_DRM_CLK_BUS).

Fix this by using Runtime PM for all clock handling. Add an explicit
dependency on CONFIG_PM, which should already be met on all affected
platforms.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/e7359a64963bd9a4f1531c2beae850774ce140bc.1694767209.git.geert+renesas@glider.be

drm/shmobile: 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 this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230507162616.1368908-40-u.kleine-koenig@pengutronix.de

drm: Place Renesas drivers in a separate dir

Create vendor specific renesas directory and move renesas drivers
to that directory.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Acked-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>