Re: [PATCH v3 07/13] drm/bridge: tc358762: Update comment about the number of lanes

From: Andreas Kemnade

Date: Fri May 29 2026 - 14:46:42 EST


On Wed, 13 May 2026 16:10:16 +0300
Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx> wrote:

> Update comment about the number of lanes.
>
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/bridge/tc358762.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/bridge/tc358762.c b/drivers/gpu/drm/bridge/tc358762.c
> index 7840ab3454f6..c5734c4df440 100644
> --- a/drivers/gpu/drm/bridge/tc358762.c
> +++ b/drivers/gpu/drm/bridge/tc358762.c
> @@ -306,7 +306,14 @@ static int tc358762_probe(struct mipi_dsi_device *dsi)
> ctx->dev = dev;
> ctx->pre_enabled = false;
>
> - /* TODO: Find out how to get dual-lane mode working */
> + /*
> + * When using DSI clk for pixel clock (only mode supported in the driver),
> + * the pclk is derived directly from the DSI byteclk via simple divider,
> + * which is either 2 or 3.
> + * The required divider can be calculated with bitspp / 8 / nlanes. Thus,
> + * for RGB888, only nlanes = 1 works as nlanes = 2 would require divider
> + * of 1.5.
> + */
> dsi->lanes = 1;
> dsi->format = MIPI_DSI_FMT_RGB888;
> dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_SYNC_PULSE |
>
wondering: I am using lanes = 2 and RGB888. But I need to write something to
SYSPLL3 register. Which somehow is sensitive to write to.... Do you have any
information about that register?

My dirty attic:
https://github.com/akemnade/linux/blob/epson-7.1rc-panel-experiments-part-upstr/drivers/gpu/drm/panel/panel-bt2.c

Regards,
Andreas