[PATCH 11/15] drm/sun4i: tcon: Fix tcon channel 1 backporch calculation

Chen-Yu Tsai wens at csie.org
Tue Mar 7 20:25:59 PST 2017


On Tue, Mar 7, 2017 at 4:56 PM, Maxime Ripard
<maxime.ripard at free-electrons.com> wrote:
> It seems like what's called a backporch in the datasheet is actually the
> backporch plus the sync period. Fix that in our driver.
>
> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
> ---
>  drivers/gpu/drm/sun4i/sun4i_tcon.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> index 93249c5ab1e4..e44217fb4f6f 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> @@ -240,15 +240,14 @@ void sun4i_tcon1_mode_set(struct sun4i_tcon *tcon, struct drm_encoder *encoder,
>                      SUN4I_TCON1_BASIC2_Y(mode->crtc_vdisplay));
>
>         /* Set horizontal display timings */
> -       bp = mode->crtc_htotal - mode->crtc_hsync_end;
> +       bp = mode->crtc_htotal - mode->crtc_hsync_start;
>         DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
>                          mode->htotal, bp);
>         regmap_write(tcon->regs, SUN4I_TCON1_BASIC3_REG,
>                      SUN4I_TCON1_BASIC3_H_TOTAL(mode->crtc_htotal) |
>                      SUN4I_TCON1_BASIC3_H_BACKPORCH(bp));
>
> -       /* Set vertical display timings */

Why remove the comment?

Otherwise,

Acked-by: Chen-Yu Tsai <wens at csie.org>

> -       bp = mode->crtc_vtotal - mode->crtc_vsync_end;
> +       bp = mode->crtc_vtotal - mode->crtc_vsync_start;
>         DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
>                          mode->vtotal, bp);
>         regmap_write(tcon->regs, SUN4I_TCON1_BASIC4_REG,
> --
> git-series 0.8.11



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