Hi,
On Sun, Sep 5, 2021 at 11:55 AM Sam Ravnborg sam@ravnborg.org wrote:
Hi Douglas,
On Wed, Sep 01, 2021 at 01:19:18PM -0700, Douglas Anderson wrote:
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@google.com/ [2] https://lore.kernel.org/r/YRTsFNTn%2FT8fLxyB@ravnborg.org/
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
Thanks for looking into this. I really like the outcome. We have panel-simple that now (mostly) handle simple panels, and thus all the eDP functionality is in a separate driver.
I have provided a few nits. My only take on this is the naming - as we do not want to confuse panel-simple and panel-edp I strongly suggest renaming the driver to panel-edp.
Sure, I'll do that. I was trying to express the fact that the new "panel-edp" driver won't actually handle _all_ eDP panels, only the eDP panels that are (comparatively) simpler. For instance, I'm not planning to handle panel-samsung-atna33xc20.c in "panel-edp". I guess people will figure it out, though.
And then rename the corresponding Kconfig entry.
With these few changes all patches are: Acked-by: Sam Ravnborg sam@ravnborg.org
Thanks, I'll add it to the patches. If there's anything major I need to change I'll give you a yell to make sure you see it.
For bisectability I suggest to move the defconfig patches up before you introduce the new Kconfig symbol. Or maybe they will be added via another tree and then this is not possible to control
Yup, I'll do that. There was some question about the defconfig patch but they are hopefully cleared up now.
I assume you will apply the patches yourself.
Sure, I can do that with your Ack. I'll also make sure that patches that Jani commented on get resolved.
-Doug