[PATCH v3 1/2] drm/bridge: Add Cadence DSI driver

[Boris Brezillon]

On Fri, 01 Sep 2017 09:51:59 +0200
Andrzej Hajda <a.hajda at samsung.com> wrote:

> On 31.08.2017 17:55, Boris Brezillon wrote:
> > Add a driver for Cadence DPI -> DSI bridge.
> >
> > This driver only support a subset of Cadence DSI bridge capabilities.
> >
> > Here is a non-exhaustive list of missing features:
> >  * burst mode
> >  * dynamic configuration of the DPHY based on the
> >  * support for additional input interfaces (SDI input)
> >
> > Signed-off-by: Boris Brezillon <boris.brezillon at free-electrons.com>
> > ---
> > Changes in v3:
> > - replace magic values by real timing calculation. The DPHY PLL clock
> >   is still hardcoded since we don't have a working DPHY block yet, and
> >   this is the piece of HW we need to dynamically configure the PLL
> >   rate based on the display refresh rate and the resolution.
> > - parse DSI devices represented with the OF-graph. This is needed to
> >   support DSI devices controlled through an external bus like I2C or
> >   SPI.
> > - use the DRM panel-bridge infrastructure to simplify the DRM panel
> >   logic
> >
> > Changes in v2:
> > - rebase on v4.12-rc1 and adapt to driver to the drm_bridge API changes
> > - return the correct error when devm_clk_get(sysclk) fails
> > - add missing depends on OF and select DRM_PANEL in the Kconfig entry
> > ---
> >  drivers/gpu/drm/bridge/Kconfig    |    9 +
> >  drivers/gpu/drm/bridge/Makefile   |    1 +
> >  drivers/gpu/drm/bridge/cdns-dsi.c | 1090 +++++++++++++++++++++++++++++++++++++
> >  3 files changed, 1100 insertions(+)
> >  create mode 100644 drivers/gpu/drm/bridge/cdns-dsi.c
> >
> > diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> > index adf9ae0e0b7c..88c324b12e16 100644
> > --- a/drivers/gpu/drm/bridge/Kconfig
> > +++ b/drivers/gpu/drm/bridge/Kconfig
> > @@ -25,6 +25,15 @@ config DRM_ANALOGIX_ANX78XX
> >  	  the HDMI output of an application processor to MyDP
> >  	  or DisplayPort.
> >  
> > +config DRM_CDNS_DSI
> > +	tristate "Cadence DPI/DSI bridge"
> > +	select DRM_KMS_HELPER
> > +	select DRM_MIPI_DSI
> > +	select DRM_PANEL  
> 
> what about:
> select DRM_PANEL_BRIDGE

Oops, indeed. I'll add this dependency.

[...]

> > +
> > +static const struct of_device_id cdns_dsi_of_match[] = {
> > +	{ .compatible = "cdns,dsi-1.3.1" },  
> 
> Do you really need version here? Wouldn't be enough checking ID_REG?
> This is only suggestion, no strong feelings.

You're right, I'll drop the version number.

> 
> The rest looks OK, so with Eric's comments addressed you can add:
> Reviewed-by: Andrzej Hajda <a.hajda at samsung.com>

Thanks for your review.

Boris