[PATCHv3 03/30] drm/omap: remove divider constraint from hsdiv
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Wed Mar 29 08:09:21 UTC 2017
Hi Tomi,
Thank you for the patch.
On Tuesday 28 Mar 2017 16:07:49 Tomi Valkeinen wrote:
> The driver only uses even dividers for hsdiv when pclk >= 100MHz, as odd
> dividers can create uneven duty cycle. However, while this holds true
> for some dividers like DISPC's LCK and PCK dividers, it is not actually
> true for hsdiv.
>
> hsdiv always produces even duty cycle, so the constraint can be removed.
>
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> ---
> drivers/gpu/drm/omapdrm/dss/dpi.c | 8 --------
> 1 file changed, 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/omapdrm/dss/dpi.c
> b/drivers/gpu/drm/omapdrm/dss/dpi.c index e75162d26ac0..e0b0c5c24c55 100644
> --- a/drivers/gpu/drm/omapdrm/dss/dpi.c
> +++ b/drivers/gpu/drm/omapdrm/dss/dpi.c
> @@ -170,14 +170,6 @@ static bool dpi_calc_hsdiv_cb(int m_dispc, unsigned
> long dispc, {
> struct dpi_clk_calc_ctx *ctx = data;
>
> - /*
> - * Odd dividers give us uneven duty cycle, causing problem when level
> - * shifted. So skip all odd dividers when the pixel clock is on the
> - * higher side.
> - */
> - if (m_dispc > 1 && m_dispc % 2 != 0 && ctx->pck_min >= 100000000)
> - return false;
> -
> ctx->pll_cinfo.mX[ctx->clkout_idx] = m_dispc;
> ctx->pll_cinfo.clkout[ctx->clkout_idx] = dispc;
--
Regards,
Laurent Pinchart
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