Re: [PATCH v2 2/8] drm/bridge/synopsys: dsi: don't call __dw_mipi_dsi_probe from dw_mipi_dsi_bind

Heiko Stübner
2018-07-03T12:32:30Z

Am Dienstag, 3. Juli 2018, 14:16:28 CEST schrieb Andrzej Hajda:
> On 18.06.2018 12:28, Heiko Stuebner wrote:
> > __dw_mipi_dsi_probe() does all the grabbing of resources and does it using
> > devm-helpers. So this is happening on each try of master bringup possibly
> > slowing down things a lot.
> >
> > Drivers using the component framework may instead want call
> > dw_mipi_dsi_probe separately in their probe function setup resources
> > early. That way the dsi bus also gets created earlier and also not
> > recreated on each bind-try, so that attached panels can load their
> > modules and be probed way before the bridge-attach in the bind call.
> >
> > So drop the call to __dw_mipi_dsi_probe and modify the function to take
> > a struct dw_mipi_dsi instead of the platform-device.
> >
> > Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> > ---
> >
> > drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 15 +++------------
> > include/drm/bridge/dw_mipi_dsi.h | 5 +----
> > 2 files changed, 4 insertions(+), 16 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> > b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c index
> > 07cde255cab2..bb4aeca5c0f9 100644
> > --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> > +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> > @@ -966,31 +966,22 @@ EXPORT_SYMBOL_GPL(dw_mipi_dsi_remove);
> >
> > /*
> >
> > * Bind/unbind API, used from platforms based on the component framework.
> > */
> >
> > -struct dw_mipi_dsi *
> > -dw_mipi_dsi_bind(struct platform_device *pdev, struct drm_encoder
> > *encoder, - const struct dw_mipi_dsi_plat_data *plat_data)
> > +int dw_mipi_dsi_bind(struct dw_mipi_dsi *dsi, struct drm_encoder
> > *encoder)
> >
> > {
> >
> > - struct dw_mipi_dsi *dsi;
> >
> > int ret;
> >
> > - dsi = __dw_mipi_dsi_probe(pdev, plat_data);
> > - if (IS_ERR(dsi))
> > - return dsi;
> > -
> >
> > ret = drm_bridge_attach(encoder, &dsi->bridge, NULL);
> > if (ret) {
> >
> > - dw_mipi_dsi_remove(dsi);
> >
> > DRM_ERROR("Failed to initialize bridge with drm\n");
> >
> > - return ERR_PTR(ret);
> > + return ret;
> >
> > }
> >
> > - return dsi;
> > + return ret;
> >
> > }
> > EXPORT_SYMBOL_GPL(dw_mipi_dsi_bind);
> >
> > void dw_mipi_dsi_unbind(struct dw_mipi_dsi *dsi)
> > {
> >
> > - __dw_mipi_dsi_remove(dsi);
> >
> > }
> > EXPORT_SYMBOL_GPL(dw_mipi_dsi_unbind);
>
> Can't we just remove these two bind/unbind functions and call
> drm_bridge_attach directly?

I guess my main motivation was to keep showing that the bridge-attach
(and any future bind actions) is the responsibility of the main driver,
but then again we can do it anyway you prefer.

So I see no problem to move this to the glue driver, if you prefer.

Heiko