Re: [PATCH 0/3] drm/panel: simple: Add mode support to devicetree
On Wed, Feb 07, 2018 at 09:16:22AM +, Eric Anholt wrote: > Sean Paul writes: > > > Hey all, > > Here's a set which allows us to add an "override" mode to the simple > > panel dt node. The override mode can be used for devices for which the > > typical display timing is not sufficient, yet the overriding mode should > > not be applied across the entire platform. > > > > An example of this (and the motivation) is the Chromebook Plus (kevin). > > If the sharp panel on this laptop is run at the mode advertised in the > > datasheet (and what is currently in mainline), it creates interference > > with the touch digitizer. To fix this, we need to run the pixel clock at > > a slightly higher rate (which we can do by increasing the back porches). > > This "fix" should not be used on other rockchip devices using this panel > > since they might not encounter the same interference. > > > > If an override mode is present, it will be checked against the panel's > > display_timing range. When validated, it will be exposed as the > > preferred mode along with the 'typical' modes generated from the panel's > > display_timing. > > > > This set is based on Linus' master to pick up the edp support in > > rk3399-gru-kevin.dts. > > Couldn't you just add a different compatible string for the panel > driver, and use that to have a different mode exposed from the panel? Yep, there's a couple ways to skin this cat. We could just change the mode to what the kevin device needs since it's the only one that uses this panel atm (that's what the original patch in the context link does). We could also expose multiple modes for the panel and let userspace sort it out. That said, we already have timing ranges in panel-simple and the goal is to leverage those such that we don't need additional compatible panels/extra modes. Sean -- Sean Paul, Software Engineer, Google / Chromium OS ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
Re: [PATCH 0/3] drm/panel: simple: Add mode support to devicetree
Sean Paul writes: > Hey all, > Here's a set which allows us to add an "override" mode to the simple > panel dt node. The override mode can be used for devices for which the > typical display timing is not sufficient, yet the overriding mode should > not be applied across the entire platform. > > An example of this (and the motivation) is the Chromebook Plus (kevin). > If the sharp panel on this laptop is run at the mode advertised in the > datasheet (and what is currently in mainline), it creates interference > with the touch digitizer. To fix this, we need to run the pixel clock at > a slightly higher rate (which we can do by increasing the back porches). > This "fix" should not be used on other rockchip devices using this panel > since they might not encounter the same interference. > > If an override mode is present, it will be checked against the panel's > display_timing range. When validated, it will be exposed as the > preferred mode along with the 'typical' modes generated from the panel's > display_timing. > > This set is based on Linus' master to pick up the edp support in > rk3399-gru-kevin.dts. Couldn't you just add a different compatible string for the panel driver, and use that to have a different mode exposed from the panel? signature.asc Description: PGP signature ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
[PATCH 0/3] drm/panel: simple: Add mode support to devicetree
Hey all, Here's a set which allows us to add an "override" mode to the simple panel dt node. The override mode can be used for devices for which the typical display timing is not sufficient, yet the overriding mode should not be applied across the entire platform. An example of this (and the motivation) is the Chromebook Plus (kevin). If the sharp panel on this laptop is run at the mode advertised in the datasheet (and what is currently in mainline), it creates interference with the touch digitizer. To fix this, we need to run the pixel clock at a slightly higher rate (which we can do by increasing the back porches). This "fix" should not be used on other rockchip devices using this panel since they might not encounter the same interference. If an override mode is present, it will be checked against the panel's display_timing range. When validated, it will be exposed as the preferred mode along with the 'typical' modes generated from the panel's display_timing. This set is based on Linus' master to pick up the edp support in rk3399-gru-kevin.dts. Thanks, Sean Cc: Doug Anderson Cc: Heiko Stuebner Cc: Jeffy Chen Cc: Rob Herring Cc: Stéphane Marchesin Cc: Thierry Reding Cc: devicet...@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: linux-rockc...@lists.infradead.org Sean Paul (3): drm/panel: simple: Add ability to override typical timing drm/panel: simple: Use display_timing for lq123p1jx31 arm64: dts: rockchip: Specify override mode for kevin panel .../bindings/display/panel/simple-panel.txt| 20 + arch/arm64/boot/dts/rockchip/rk3399-gru-kevin.dts | 14 drivers/gpu/drm/panel/panel-simple.c | 96 ++ 3 files changed, 115 insertions(+), 15 deletions(-) -- 2.16.0.rc1.238.g530d649a79-goog ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
