Re: [PATCH v1 2/5] drm/bridge: tc358768: Support pulse mode

From: Robert Foss
Date: Tue Oct 19 2021 - 04:55:29 EST


On Sun, 3 Oct 2021 at 01:35, Dmitry Osipenko <digetx@xxxxxxxxx> wrote:
>
> Support pulse-mode synchronization which is supported and used by simple
> DSI panels like Panasonic VVX10F004B00.
>
> Tested-by: Andreas Westman Dorcsak <hedmoo@xxxxxxxxx> # Asus TF700T
> Tested-by: Maxim Schwalm <maxim.schwalm@xxxxxxxxx> #TF700T
> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
> ---
> drivers/gpu/drm/bridge/tc358768.c | 66 ++++++++++++++++++++++---------
> 1 file changed, 48 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
> index 18ae6605a803..10ebd0621ad3 100644
> --- a/drivers/gpu/drm/bridge/tc358768.c
> +++ b/drivers/gpu/drm/bridge/tc358768.c
> @@ -785,24 +785,54 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge)
> /* START[0] */
> tc358768_write(priv, TC358768_STARTCNTRL, 1);
>
> - /* Set event mode */
> - tc358768_write(priv, TC358768_DSI_EVENT, 1);
> -
> - /* vsw (+ vbp) */
> - tc358768_write(priv, TC358768_DSI_VSW,
> - mode->vtotal - mode->vsync_start);
> - /* vbp (not used in event mode) */
> - tc358768_write(priv, TC358768_DSI_VBPR, 0);
> - /* vact */
> - tc358768_write(priv, TC358768_DSI_VACT, mode->vdisplay);
> -
> - /* (hsw + hbp) * byteclk * ndl / pclk */
> - val = (u32)div_u64((mode->htotal - mode->hsync_start) *
> - ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
> - mode->clock * 1000);
> - tc358768_write(priv, TC358768_DSI_HSW, val);
> - /* hbp (not used in event mode) */
> - tc358768_write(priv, TC358768_DSI_HBPR, 0);
> + if (dsi_dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
> + /* Set pulse mode */
> + tc358768_write(priv, TC358768_DSI_EVENT, 0);
> +
> + /* vact */
> + tc358768_write(priv, TC358768_DSI_VACT, mode->vdisplay);
> +
> + /* vsw */
> + tc358768_write(priv, TC358768_DSI_VSW,
> + mode->vsync_end - mode->vsync_start);
> + /* vbp */
> + tc358768_write(priv, TC358768_DSI_VBPR,
> + mode->vtotal - mode->vsync_end);
> +
> + /* hsw * byteclk * ndl / pclk */
> + val = (u32)div_u64((mode->hsync_end - mode->hsync_start) *
> + ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
> + mode->clock * 1000);
> + tc358768_write(priv, TC358768_DSI_HSW, val);
> +
> + /* hbp * byteclk * ndl / pclk */
> + val = (u32)div_u64((mode->htotal - mode->hsync_end) *
> + ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
> + mode->clock * 1000);
> + tc358768_write(priv, TC358768_DSI_HBPR, val);
> + } else {
> + /* Set event mode */
> + tc358768_write(priv, TC358768_DSI_EVENT, 1);
> +
> + /* vact */
> + tc358768_write(priv, TC358768_DSI_VACT, mode->vdisplay);
> +
> + /* vsw (+ vbp) */
> + tc358768_write(priv, TC358768_DSI_VSW,
> + mode->vtotal - mode->vsync_start);
> + /* vbp (not used in event mode) */
> + tc358768_write(priv, TC358768_DSI_VBPR, 0);
> +
> + /* (hsw + hbp) * byteclk * ndl / pclk */
> + val = (u32)div_u64((mode->htotal - mode->hsync_start) *
> + ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
> + mode->clock * 1000);
> + tc358768_write(priv, TC358768_DSI_HSW, val);
> +
> + /* hbp (not used in event mode) */
> + tc358768_write(priv, TC358768_DSI_HBPR, 0);
> + }
> +
> /* hact (bytes) */
> tc358768_write(priv, TC358768_DSI_HACT, hact);
>

Reviewed-by: Robert Foss <robert.foss@xxxxxxxxxx>