drm/mediatek: mtk_disp_gamma: Fix breakage due to merge issue

While the commit that was sent to the mailing lists was fine, something
happened during merge and the mtk_gamma_set() function got broken as
a writel() was turned into a readl().

Fix that by changing that back to the expected writel().

Fixes: a6b39cd248f3 ("drm/mediatek: De-commonize disp_aal/disp_gamma gamma_set functions")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231025104940.140605-1-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Add kerneldoc for struct mtk_disp_gamma

The mtk_disp_gamma structure was completely undocumented: add some
kerneldoc documentation to it.

Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-16-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Program gamma LUT type for descending or rising

All of the SoCs that don't have dithering control in the gamma IP
have got a GAMMA_LUT_TYPE bit that tells to the IP if the LUT is
"descending" (bit set) or "rising" (bit cleared): make sure to set
it correctly after programming the LUT.

Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-14-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Make sure relay mode is disabled

Disable relay mode at the end of LUT programming to make sure that the
processed image goes through in both DISP_GAMMA and DISP_AAL for gamma
setting.

Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-13-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Add support for MT8195

Now that this driver supports 12-bit LUTs, we can add support for the
DISP_GAMMA found on the MT8195 SoC: add its driver data and compatible.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-12-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Add support for 12-bit LUT

New SoCs, like MT8195, not only may support bigger lookup tables, but
have got a different register layout to support bigger precision:
support specifying the number of `lut_bits` for each SoC and use it
in mtk_gamma_set_common() to perform the right calculations and add
support for 12-bit gamma lookup tables.

While at it, also reorder the variables in mtk_gamma_set_common()
and rename `lut_base` to `lut0_base` to improve readability.

Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-11-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Support multi-bank gamma LUT

Newer Gamma IP have got multiple LUT banks: support specifying the
size of the LUT banks and handle bank-switching before programming
the LUT in mtk_gamma_set_common() in preparation for adding support
for MT8195 and newer SoCs.

Suggested-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
[Angelo: Refactored original commit]
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-10-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: De-commonize disp_aal/disp_gamma gamma_set functions

In preparation for adding a 12-bits gamma support for the DISP_GAMMA
IP, remove the mtk_gamma_set_common() function and move the relevant
bits in mtk_gamma_set() for DISP_GAMMA and mtk_aal_gamma_set() for
DISP_AAL: since the latter has no more support for gamma manipulation
(being moved to a different IP) in newer revisions, those functions
are about to diverge and it makes no sense to keep a common one (with
all the complications of passing common data and making exclusions
for device driver data) for just a few bits.

This commit brings no functional changes.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-9-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Use bitfield macros

Make the code more robust and improve readability by using bitfield
macros instead of open coding bit operations.

Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-7-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Enable the Gamma LUT table only after programming

Move the write to DISP_GAMMA_CFG to enable the Gamma LUT to after
programming the actual table to avoid potential visual glitches during
table modification.

Note:
GAMMA should get enabled in between vblanks, but this requires many
efforts in order to make this happen, as that requires migrating all
of the writes to make use of CMDQ instead of cpu writes and that's
not trivial. For this reason, this patch only moves the LUT enable.
The CMDQ rework will come at a later time.

Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-6-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Improve and simplify HW LUT calculation

Use drm_color_lut_extract() to avoid open-coding the bits reduction
calculations for each color channel and use a struct drm_color_lut
to temporarily store the information instead of an array of u32.

Also, slightly improve the precision of the HW LUT calculation in the
LUT DIFF case by performing the subtractions on the 16-bits values and
doing the 10 bits conversion later.

Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-5-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Support SoC specific LUT size

Newer SoCs support a bigger Gamma LUT table: wire up a callback
to retrieve the correct LUT size for each different Gamma IP.

Co-developed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
[Angelo: Rewritten commit message/description + porting]
Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-4-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Reduce indentation in mtk_gamma_set_common()

Invert the check for state->gamma_lut and move it at the beginning
of the function to reduce indentation: this prepares the code for
keeping readability on later additions.

This commit brings no functional changes.

Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-3-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: gamma: Adjust mtk_drm_gamma_set_common parameters

Adjust the parameters in mtk_drm_gamma_set_common()
- add (struct device *dev) to get lut_diff from gamma's driver data
- remove (bool lut_diff) and use false as default value in the function

Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-2-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: 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 mediatek 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>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230507162616.1368908-30-u.kleine-koenig@pengutronix.de

drm/mediatek: 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 mediatek drm drivers from always returning zero in
the remove callback to the void returning variant.

Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Jyri Sarha <jyri.sarha@iki.fi>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20230801110239.831099-8-u.kleine-koenig@pengutronix.de/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

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/mediatek: Include missing headers

Fix the follow sparse warnings by adding missing headers:

drivers/gpu/drm/mediatek/mtk_cec.c:251:24: sparse: warning: symbol 'mtk_cec_driver' was not declared. Should it be static?
drivers/gpu/drm/mediatek/mtk_disp_ccorr.c:221:24: sparse: warning: symbol 'mtk_disp_ccorr_driver' was not declared. Should it be static?
drivers/gpu/drm/mediatek/mtk_disp_rdma.c:390:24: sparse: warning: symbol 'mtk_disp_rdma_driver' was not declared. Should it be static?
drivers/gpu/drm/mediatek/mtk_disp_gamma.c:209:24: sparse: warning: symbol 'mtk_disp_gamma_driver' was not declared. Should it be static?
drivers/gpu/drm/mediatek/mtk_disp_ovl.c:565:24: sparse: warning: symbol 'mtk_disp_ovl_driver' was not declared. Should it be static?
drivers/gpu/drm/mediatek/mtk_disp_color.c:164:24: sparse: warning: symbol 'mtk_disp_color_driver' was not declared. Should it be static?
drivers/gpu/drm/mediatek/mtk_disp_aal.c:161:24: sparse: warning: symbol 'mtk_disp_aal_driver' was not declared. Should it be static?
drivers/gpu/drm/mediatek/mtk_dpi.c:1109:24: sparse: warning: symbol 'mtk_dpi_driver' was not declared. Should it be static?
drivers/gpu/drm/mediatek/mtk_hdmi_ddc.c:340:24: sparse: warning: symbol 'mtk_hdmi_ddc_driver' was not declared. Should it be static?
drivers/gpu/drm/mediatek/mtk_dsi.c:1223:24: sparse: warning: symbol 'mtk_dsi_driver' was not declared. Should it be static?

Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20230110091647.13265-1-miles.chen@mediatek.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: Add lut diff flag for new gamma hardware support

mt8183 gamma module usage is different with before soc,
gamma odd(index start from 0) lut value set to hardware
register should be
the difference of current lut value with last lut value.

for example, chrome os user space set lut
like this(only r chanel for example):
2 4 6 8 10 12.
1) mt8183 gamma driver should set the gamma lut to hardware
register like this:
2 [2] 6 [2] 10 [2]
the value with [] is the difference value
2)gamma hardware process display data with original lut

Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20220428085829.15855-2-yongqiang.niu@mediatek.com/
Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.corp-partner.google.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek/mtk_disp_gamma: Strip and demote non-conformant kernel-doc header

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

drivers/gpu/drm/mediatek/mtk_disp_gamma.c:42: warning: Function parameter or member 'clk' not described in 'mtk_disp_gamma'
drivers/gpu/drm/mediatek/mtk_disp_gamma.c:42: warning: Function parameter or member 'regs' not described in 'mtk_disp_gamma'
drivers/gpu/drm/mediatek/mtk_disp_gamma.c:42: warning: Function parameter or member 'cmdq_reg' not described in 'mtk_disp_gamma'
drivers/gpu/drm/mediatek/mtk_disp_gamma.c:42: warning: Function parameter or member 'data' not described in 'mtk_disp_gamma'

Cc: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210602143300.2330146-3-lee.jones@linaro.org

drm/mediatek: Add support for SoC MT8183

1. Add ovl private data
2. Add rdma private data
3. Add gamma privte data
4. Add main and external path module for crtc create

Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: Add has_dither private data for gamma

Not all SoC has dither function in gamma module.
Add private data to control this function setting.

Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drm/mediatek: Separate gamma module

mt8183 gamma module will different with mt8173,
so separate gamma for adding private data.

Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>