[PATCH v3 00/16] eDP: Support probing eDP panels dynamically instead of hardcoding

From: Douglas Anderson
Date: Wed Sep 01 2021 - 16:20:37 EST


The goal of this patch series is to move away from hardcoding exact
eDP panels in device tree files. As discussed in the various patches
in this series (I'm not repeating everything here), most eDP panels
are 99% probable and we can get that last 1% by allowing two "power
up" delays to be specified in the device tree file and then using the
panel ID (found in the EDID) to look up additional power sequencing
delays for the panel.

This patch series is the logical contiunation of a previous patch
series where I proposed solving this problem by adding a
board-specific compatible string [1]. In the discussion that followed
it sounded like people were open to something like the solution
proposed in this new series.

In version 2 I got rid of the idea that we could have a "fallback"
compatible string that we'd use if we didn't recognize the ID in the
EDID. This simplifies the bindings a lot and the implementation
somewhat. As a result of not having a "fallback", though, I'm not
confident in transitioning any existing boards over to this since
we'll have to fallback to very conservative timings if we don't
recognize the ID from the EDID and I can't guarantee that I've seen
every panel that might have shipped on an existing product. The plan
is to use "edp-panel" only on new boards or new revisions of old
boards where we can guarantee that every EDID that ships out of the
factory has an ID in the table.

Version 3 of this series now splits out all eDP panels to their own
driver and adds the generic eDP panel support to this new driver. I
believe this is what Sam was looking for [2].

[1] https://lore.kernel.org/r/YFKQaXOmOwYyeqvM@xxxxxxxxxx/
[2] https://lore.kernel.org/r/YRTsFNTn%2FT8fLxyB@xxxxxxxxxxxx/

Changes in v3:
- Decode hex product ID w/ same endianness as everyone else.
- ("Reorder logicpd_type_28...") patch new for v3.
- Split eDP panels patch new for v3.
- Move wayward panels patch new for v3.
- ("Non-eDP panels don't need "HPD" handling") new for v3.
- Split the delay structure out patch just on eDP now.
- ("Better describe eDP panel delays") new for v3.
- Fix "prepare_to_enable" patch new for v3.
- ("Don't re-read the EDID every time") moved to eDP only patch.
- Generic "edp-panel" handled by the eDP panel driver now.
- Change init order to we power at the end.
- Adjust endianness of product ID.
- Fallback to conservative delays if panel not recognized.
- Add Sharp LQ116M1JW10 to table.
- Add AUO B116XAN06.1 to table.
- Rename delays more generically so they can be reused.

Changes in v2:
- No longer allow fallback to panel-simple.
- Add "-ms" suffix to delays.
- Don't support a "fallback" panel. Probed panels must be probed.
- Not based on patch to copy "desc"--just allocate for probed panels.
- Add "-ms" suffix to delays.

Douglas Anderson (16):
dt-bindings: drm/panel-simple-edp: Introduce generic eDP panels
drm/edid: Break out reading block 0 of the EDID
drm/edid: Allow the querying/working with the panel ID from the EDID
drm/panel-simple: Reorder logicpd_type_28 / mitsubishi_aa070mc01
drm/panel-simple-edp: Split eDP panels out of panel-simple
ARM: configs: Everyone who had PANEL_SIMPLE now gets PANEL_SIMPLE_EDP
arm64: defconfig: Everyone who had PANEL_SIMPLE now gets
PANEL_SIMPLE_EDP
MIPS: configs: Everyone who had PANEL_SIMPLE now gets PANEL_SIMPLE_EDP
drm/panel-simple-edp: Move some wayward panels to the eDP driver
drm/panel-simple: Non-eDP panels don't need "HPD" handling
drm/panel-simple-edp: Split the delay structure out
drm/panel-simple-edp: Better describe eDP panel delays
drm/panel-simple-edp: hpd_reliable shouldn't be subtraced from
hpd_absent
drm/panel-simple-edp: Fix "prepare_to_enable" if panel doesn't handle
HPD
drm/panel-simple-edp: Don't re-read the EDID every time we power off
the panel
drm/panel-simple-edp: Implement generic "edp-panel"s probed by EDID

.../bindings/display/panel/panel-edp.yaml | 188 ++
arch/arm/configs/at91_dt_defconfig | 1 +
arch/arm/configs/exynos_defconfig | 1 +
arch/arm/configs/imx_v6_v7_defconfig | 1 +
arch/arm/configs/lpc32xx_defconfig | 1 +
arch/arm/configs/multi_v5_defconfig | 1 +
arch/arm/configs/multi_v7_defconfig | 1 +
arch/arm/configs/omap2plus_defconfig | 1 +
arch/arm/configs/qcom_defconfig | 1 +
arch/arm/configs/realview_defconfig | 1 +
arch/arm/configs/sama5_defconfig | 1 +
arch/arm/configs/shmobile_defconfig | 1 +
arch/arm/configs/sunxi_defconfig | 1 +
arch/arm/configs/tegra_defconfig | 1 +
arch/arm/configs/versatile_defconfig | 1 +
arch/arm/configs/vexpress_defconfig | 1 +
arch/arm64/configs/defconfig | 1 +
arch/mips/configs/qi_lb60_defconfig | 1 +
arch/mips/configs/rs90_defconfig | 1 +
drivers/gpu/drm/drm_edid.c | 121 +-
drivers/gpu/drm/panel/Kconfig | 16 +-
drivers/gpu/drm/panel/Makefile | 1 +
drivers/gpu/drm/panel/panel-simple-edp.c | 1895 +++++++++++++++++
drivers/gpu/drm/panel/panel-simple.c | 1100 +---------
include/drm/drm_edid.h | 47 +
25 files changed, 2293 insertions(+), 1093 deletions(-)
create mode 100644 Documentation/devicetree/bindings/display/panel/panel-edp.yaml
create mode 100644 drivers/gpu/drm/panel/panel-simple-edp.c

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