[0/8] drm: mxsfb: Allow overriding bus width

Message

Laurent Pinchart Aug. 13, 2020, 1:29 a.m. UTC

Hello,

This patch series adds support to the mxsfb driver for bus width
override. The need came from a hardware platform where a 18-bpp panel
had the R[5:0], G[5:0] and B[5:0] signals connected to LCD_DATA[7:2],
LCD_DATA[15:10] and LCD_DATA[23:18] instead of LCD_DATA[5:0],
LCD_DATA[11:6] and LCD_DATA[17:12]. The bus width, automatically
configured to 18 by querying the panel, is incorrect in this case, and
needs to be set to 24.

To solve this issue, a new bus-width DT property is added to the mxsfb
DT binding. Patch 1/8 first converts the binding to YAML, with a fix for
the compatible string values in 2/8. Patch 3/8 then adds the new
property, and 4/8 renames the binding file to fsl,lcdif.yaml to match
the usual naming convention. I've kept that patch last to make it easy
to drop should should mxsfb.yaml be preferred.

Patches 5/8 to 6/8 then fix the DT sources to match the LCDIF bindings,
as I noticed during the conversion that the compatible strings were
badly managed (see patch 2/8 for a longer explanation). Patch 7/8 drops
an unused clock from DT sources.

Patch 8/8 finally adds support for the bus-width property to the mxsfb
driver.

Laurent Pinchart (8):
  dt-bindings: display: mxsfb: Convert binding to YAML
  dt-bindings: display: mxsfb: Add and fix compatible strings
  dt-bindings: display: mxsfb: Add a bus-width endpoint property
  dt-bindings: display: mxsfb: Rename to fsl,lcdif.yaml
  ARM: dts: imx: Fix LCDIF compatible strings
  arm64: dts: imx8mq: Fix LCDIF compatible strings
  ARM: dts: imx: Remove unneeded LCDIF disp_axi clock
  drm: mxsfb: Add support for the bus-width DT property

 .../bindings/display/fsl,lcdif.yaml           | 135 ++++++++++++++++++
 .../devicetree/bindings/display/mxsfb.txt     |  87 -----------
 MAINTAINERS                                   |   2 +-
 arch/arm/boot/dts/imx6sl.dtsi                 |   7 +-
 arch/arm/boot/dts/imx6sll.dtsi                |   7 +-
 arch/arm/boot/dts/imx6sx.dtsi                 |   4 +-
 arch/arm/boot/dts/imx6ul.dtsi                 |   7 +-
 arch/arm64/boot/dts/freescale/imx8mq.dtsi     |   2 +-
 drivers/gpu/drm/mxsfb/mxsfb_drv.c             |  26 ++++
 drivers/gpu/drm/mxsfb/mxsfb_drv.h             |   2 +
 drivers/gpu/drm/mxsfb/mxsfb_kms.c             |   8 +-
 11 files changed, 182 insertions(+), 105 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/display/fsl,lcdif.yaml
 delete mode 100644 Documentation/devicetree/bindings/display/mxsfb.txt