On 2023-05-22 04:16:20, Dmitry Baryshkov wrote:
<snip>
> > + if (ctx->dsi->dsc) {
>
> dsi->dsc is always set, thus this condition can be dropped.
I want to leave room for possibly running the panel without DSC (at a
lower resolution/refresh rate, or at higher power consumption if there
is enough BW) by not assigning the pointer, if we get access to panel
documentation: probably one of the magic commands sent in this driver
controls it but we don't know which.
> > + drm_dsc_pps_payload_pack(&pps, ctx->dsi->dsc);
> > +
> > + ret = mipi_dsi_picture_parameter_set(ctx->dsi, &pps);
> > + if (ret < 0) {
> > + dev_err(panel->dev, "failed to transmit PPS: %d\n",
> > ret);
> > + goto fail;
> > + }
> > + ret = mipi_dsi_compression_mode(ctx->dsi, true);
> > + if (ret < 0) {
> > + dev_err(dev, "failed to enable compression mode: %d\n",
> > ret);
> > + goto fail;
> > + }
> > +
> > + msleep(28);
> > + }
> > +
> > + ctx->prepared = true;
> > + return 0;
> > +
> > +fail:
> > + gpiod_set_value_cansleep(ctx->reset_gpio, 0);
> > + regulator_disable(ctx->vddio);
> > + return ret;
> > +}
<snip>
> > + /* This panel only supports DSC; unconditionally enable it */
On that note I should perhaps reword this.
> > + dsi->dsc = dsc = devm_kzalloc(&dsi->dev, sizeof(*dsc), GFP_KERNEL);
>
> I think double assignments are frowned upon.
Ack.
>
> > + if (!dsc)
> > + return -ENOMEM;
> > +
> > + dsc->dsc_version_major = 1;
> > + dsc->dsc_version_minor = 1;
> > +
> > + dsc->slice_height = 32;
> > + dsc->slice_count = 2;
> > + // TODO: Get hdisplay from the mode
>
> Would you like to fix the TODO?
I can't unless either migrating to drm_bridge (is that doable?) or
expand drm_panel. That's a larger task, but I don't think this driver
is the right place to track that desire. Should I drop the comment
entirely or reword it?
> > + WARN_ON(1440 % dsc->slice_count);
> > + dsc->slice_width = 1440 / dsc->slice_count;
<snip>
- Marijn
