linux-stable.git/drivers/gpu/drm/mcde, branch linux-5.10.y

drm/mcde: Enable module autoloading

2024-12-14T18:48:26+00:00

[ Upstream commit 8a16b5cdae26207ff4c22834559384ad3d7bc970 ]

Add MODULE_DEVICE_TABLE(), so modules could be properly autoloaded based
on the alias from of_device_id table.

Signed-off-by: Liao Chen 
Reviewed-by: Linus Walleij 
Link: https://patchwork.freedesktop.org/patch/msgid/20240902113320.903147-4-liaochen4@huawei.com
Signed-off-by: Dmitry Baryshkov 
Signed-off-by: Sasha Levin

drm/mcde: Fix refcount leak in mcde_dsi_bind

2022-08-21T13:15:41+00:00

[ Upstream commit 3a149169e4a2f9127022fec6ef5d71b4e804b3b9 ]

Every iteration of for_each_available_child_of_node() decrements
the reference counter of the previous node. There is no decrement
when break out from the loop and results in refcount leak.
Add missing of_node_put() to fix this.

Fixes: 5fc537bfd000 ("drm/mcde: Add new driver for ST-Ericsson MCDE")
Signed-off-by: Miaoqian Lin 
Signed-off-by: Linus Walleij 
Link: https://patchwork.freedesktop.org/patch/msgid/20220525115411.65455-1-linmq006@gmail.com
Signed-off-by: Sasha Levin

drm/mcde: Fix off by 10^3 in calculation

2021-06-16T10:01:44+00:00

commit c8a570443943304cac2e4186dbce6989b6c2b8b5 upstream.

The calclulation of how many bytes we stuff into the
DSI pipeline for video mode panels is off by three
orders of magnitude because we did not account for the
fact that the DRM mode clock is in kilohertz rather
than hertz.

This used to be:
drm_mode_vrefresh(mode) * mode->htotal * mode->vtotal
which would become for example for s6e63m0:
60 x 514 x 831 = 25628040 Hz, but mode->clock is
25628 as it is in kHz.

This affects only the Samsung GT-I8190 "Golden" phone
right now since it is the only MCDE device with a video
mode display.

Curiously some specimen work with this code and wild
settings in the EOL and empty packets at the end of the
display, but I have noticed an eeire flicker until now.
Others were not so lucky and got black screens.

Cc: Ville Syrjälä 
Reported-by: Stephan Gerhold 
Fixes: 920dd1b1425b ("drm/mcde: Use mode->clock instead of reverse calculating it from the vrefresh")
Signed-off-by: Linus Walleij 
Tested-by: Stephan Gerhold 
Reviewed-by: Stephan Gerhold 
Link: https://patchwork.freedesktop.org/patch/msgid/20210608213318.3897858-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman

drm/mcde/panel: Inverse misunderstood flag

2021-05-14T07:50:22+00:00

[ Upstream commit d0c5ac04e7feedbc069f26f4dcbf35b521ae7fc5 ]

A recent patch renaming MIPI_DSI_MODE_EOT_PACKET to
MIPI_DSI_MODE_NO_EOT_PACKET brought to light the
misunderstanding in the current MCDE driver and all
its associated panel drivers that MIPI_DSI_MODE_EOT_PACKET
would mean "use EOT packet" when in fact it means the
reverse.

Fix it up by implementing the flag right in the MCDE
DSI driver and remove the flag from panels that actually
want the EOT packet.

Suggested-by: Nicolas Boichat 
Signed-off-by: Linus Walleij 
Reviewed-by: Nicolas Boichat 
Fixes: 5fc537bfd000 ("drm/mcde: Add new driver for ST-Ericsson MCDE")
Fixes: 899f24ed8d3a ("drm/panel: Add driver for Novatek NT35510-based panels")
Fixes: ac1d6d74884e ("drm/panel: Add driver for Samsung S6D16D0 panel")
Fixes: 435e06c06cb2 ("drm/panel: s6e63m0: Add DSI transport")
Fixes: 8152c2bfd780 ("drm/panel: Add driver for Sony ACX424AKP panel")
Link: https://patchwork.freedesktop.org/patch/msgid/20210304004138.1785057-1-linus.walleij@linaro.org
Signed-off-by: Sasha Levin

drm/mcde: Fix handling of platform_get_irq() error

2020-12-30T10:52:56+00:00

[ Upstream commit e2dae672a9d5e11856fe30ede63467c65f999a81 ]

platform_get_irq() returns -ERRNO on error.  In such case comparison
to 0 would pass the check.

Fixes: 5fc537bfd000 ("drm/mcde: Add new driver for ST-Ericsson MCDE")
Signed-off-by: Krzysztof Kozlowski 
Acked-by: Linus Walleij 
Signed-off-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20200827071107.27429-1-krzk@kernel.org
Signed-off-by: Sasha Levin

drm/mcde: Fix unbalanced regulator

2020-11-10T23:27:53+00:00

Since we now turn off the EPOD regulator to reset the
hardware, we need to balance the regulators after that
point. If registering the master fails we only need
to disable one regulator. Fix this by open-coding
this leg of the error path.

Fixes: c4842d4d0f74 ("drm/mcde: Fix display pipeline restart")
Signed-off-by: Linus Walleij 
Reviewed-by: Sam Ravnborg 
Cc: Stephan Gerhold 
Link: https://patchwork.freedesktop.org/patch/msgid/20201108113535.1819952-1-linus.walleij@linaro.org

drm/mcde: Retry DSI read/write transactions

2020-08-15T10:14:18+00:00

The vendor driver makes a few retries on read DSI
transactions, something that is needed especially in
case of read (such as reading the panel MTP ID) while
the panel is running in video mode. This happens on
the Samsung s6e63m0 panel on the Golden device.

Retry reads and writes alike three times.

Signed-off-by: Linus Walleij 
Reviewed-by: Stephan Gerhold 
Cc: Stephan Gerhold 
Link: https://patchwork.freedesktop.org/patch/msgid/20200814194451.3494294-1-linus.walleij@linaro.org

drm/mcde: Enable the DSI link with display

2020-08-13T14:39:26+00:00

The MCDE DSI link hardware which is modeled like a bridge
in DRM, connected further to the panel bridge, creating
a pipeline.

We have been using the .pre_enable(), .enable(),
.disable() and .post_disable() callbacks from the bridge
to set this up in a chained manner: first the display
controller goes online and then in successive order
each bridge in the pipeline. Inside DRM it works
like this:

drm_atomic_helper_commit_tail()
  drm_atomic_helper_commit_modeset_enables()
    struct drm_crtc_helper_funcs .atomic_enable()
      struct drm_simple_display_pipe_funcs .enable()
        MCDE display enable call
    drm_atomic_bridge_chain_enable()
      struct drm_bridge_funcs .pre_enable()
        mcde_dsi_bridge_pre_enable()
        panel_bridge_pre_enable()
          struct drm_panel_funcs .prepare()
      struct drm_bridge_funcs .enable()
        mcde_dsi_bridge_enable()
        panel_bridge_enable()
          struct drm_panel_funcs .enable()

A similar sequence is executed for disabling.

Unfortunately this is not what the hardware needs: at
a certain stage in the enablement of the display
controller the DSI link needs to come up to support
video mode, else something (like a FIFO flow) locks
up the hardware and we never get picture.

Fix this by simply leaving the pre|enable and
post|disable callbacks unused, and establish two
cross-calls from the display controller to bring up
the DSI link at the right place in the display
bring-up sequence and vice versa in the shutdown
sequence.

For command mode displays, it works just fine to
also enable the display flow early. The only time
we hold it back right now is in one-shot mode,
on-demand display updates.

When combined with the previous patch and some patches
for the S6E63M0 display controller to support DSI
mode, this gives working display on the Samsung
GT-I8190 (Golden) phone. It has also been tested working
on the Samsung GT-S7710 (Skomer) phone.

Signed-off-by: Linus Walleij 
Acked-by: Daniel Vetter 
Cc: newbytee@protonmail.com
Cc: Stephan Gerhold 
Link: https://patchwork.freedesktop.org/patch/msgid/20200808223122.1492124-4-linus.walleij@linaro.org

drm/mcde: Fix display pipeline restart

2020-08-13T14:39:19+00:00

To make sure that the MCDE is in a reasonable state during
set-up, perform a reset by power cycling the block by dropping
the on-chip regulator reference after probe. The display
subsystem (DSS) has no dedicated reset line so dropping
the EPOD regulator is the only real way of resetting it.

We introduce code to enable and disable the regulator in
the display enable/disable callbacks.

We move the generic MCDE setup such as muxing of DPI
signals and masking of interrupts to the display
handling.

When we drop the power to the whole display subsystem, not
only MCDE but also the DSI links lose their state. Therefore
we move the DSI block reset and hardware initialization
code to the mcde_dsi_bridge_pre_enable() callback so this
happens every time we start up the bridge, as we may have
lost the power.

We move the final disablement of the interrupts and
clocks to the mcde_dsi_bridge_post_disable() callback
rather than have it in the mcde_dsi_bridge_disable()
callback, as some control messages may still be sent
over the DSI host after the bridge has been shut down.

This (together with a patch for the corresponding
panel) makes the Samsung GT-S7710 successfully disable
and re-enable its display, cutting all power while
disabled and re-initializing the hardware when coming
back up.

Acked-by: Daniel Vetter 
Signed-off-by: Linus Walleij 
Cc: newbytee@protonmail.com
Cc: Stephan Gerhold 
Link: https://patchwork.freedesktop.org/patch/msgid/20200808223122.1492124-3-linus.walleij@linaro.org

drm/mcde: Support using DSI in LP mode

2020-08-13T14:39:15+00:00

It is possible to set a flag in the struct mipi_dsi_device
so the panel is handled in low power (LP) mode. Some displays
only support this mode and it is also good for testing.

Signed-off-by: Linus Walleij 
Acked-by: Daniel Vetter 
Cc: newbytee@protonmail.com
Cc: Stephan Gerhold 
Link: https://patchwork.freedesktop.org/patch/msgid/20200808223122.1492124-2-linus.walleij@linaro.org