Re: [PATCH 0/6] drm/tiny/st7735r: Match up with staging/fbtft driver

["Noralf Trønnes" <noralf@tronnes.org>]

Den 24.11.2021 16.07, skrev Noralf Trønnes:
> Hi,
> 
> This patchset adds a missing piece for decommissioning the
> staging/fbtft/fb_st7735r.c driver namely a way to configure the
> controller from Device Tree.
> 
> All fbtft drivers have builtin support for one display panel and all
> other panels using that controller are configured using the Device Tree
> 'init' property. This property is supported by all fbtft drivers and
> provides a generic way to set register values or issue commands
> (depending on the type of controller).
> 
> It is common for these types of displays to have a datasheet listing the
> necessary controller settings/commands or some example code doing the
> same.
> 
> This is how the panel directly supported by the fb_st7735r staging
> driver is described using Device Tree with that driver:
> 
>     width = <160>;
>     height = <128>;
> 
>     init = <0x1000001
>             0x2000096
>             0x1000011
>             0x20000ff
>             0x10000B1 0x01 0x2C 0x2D
>             0x10000B4 0x07
>             0x10000C0 0xA2 0x02 0x84
>             0x10000C1 0xC5
>             0x10000C2 0x0A 0x00
>             0x10000C5 0x0E
>             0x100003a 0x55
>             0x1000036 0x60
>             0x10000E0 0x0F 0x1A 0x0F 0x18 0x2F 0x28 0x20 0x22
>                       0x1F 0x1B 0x23 0x37 0x00 0x07 0x02 0x10
>             0x10000E1 0x0F 0x1B 0x0F 0x17 0x33 0x2C 0x29 0x2E
>                       0x30 0x30 0x39 0x3F 0x00 0x07 0x03 0x10
>             0x1000029
>             0x2000064>;
> 
> 
> This is how the same panel is described using the st7735r drm driver and
> this patchset:
> 
>     width = <160>;
>     height = <128>;
> 
>     frmctr1 = [ 01 2C 2D ];
>     invctr = [ 07 ];
>     pwctr1 = [ A2 02 84 ];
>     pwctr2 = [ C5 ];
>     pwctr3 = [ 0A 00 ];
>     vmctr1 = [ 0E ];
>     madctl = [ 60 ];
>     gamctrp1 = [ 0F 1A 0F 18 2F 28 20 22 1F 1B 23 37 00 07 02 10 ];
>     gamctrn1 = [ 0F 1B 0F 17 33 2C 29 2E 30 30 39 3F 00 07 03 10 ];
> 
> 
> Back when the fbtft drivers were added to staging I asked on the DT
> mailinglist if it was OK to use the 'init' property but it was turned
> down. In this patchset I'm trying the same approach used by the
> solomon,ssd1307fb.yaml binding in describing the attached panel. That
> binding prefixes the properties with the vendor name, not sure why that
> is and I think it looks strange so I try without it.
> 
> Noralf.
> 
> 
> Noralf Trønnes (6):
>   dt-bindings: display: sitronix,st7735r: Fix backlight in example
>   dt-bindings: display: sitronix,st7735r: Make reset-gpios optional
>   dt-bindings: display: sitronix,st7735r: Remove spi-max-frequency limit

Patches 1-3 applied, thanks for reviewing.

The change to the driver has been replaced by a new generic driver
panel-mipi-dbi.

Noralf.

>   dt-bindings: display: sitronix,st7735r: Add initialization properties
>   drm/mipi-dbi: Add device property functions
>   drm: tiny: st7735r: Support DT initialization of controller
> 
>  .../bindings/display/sitronix,st7735r.yaml    | 122 ++++++++++++++-
>  drivers/gpu/drm/drm_mipi_dbi.c                | 139 ++++++++++++++++++
>  drivers/gpu/drm/tiny/st7735r.c                |  87 +++++++++--
>  include/drm/drm_mipi_dbi.h                    |   3 +
>  4 files changed, 334 insertions(+), 17 deletions(-)
>