On Wed, Mar 2, 2011 at 1:50 PM, Tomi Valkeinen <tomi.valkeinen@xxxxxx> wrote:
>
> When using OMAP2_DSS_USE_DSI_PLL, which selects DSI PLL as source clock
> for DISPC, the DSI needs the vdds_dsi regulator. Latest regulator
> changes broke this, causing the the code to not acquire the regulator
> when using OMAP2_DSS_USE_DSI_PLL.
>
> This patch acquires the vdds_dsi regulator in dsi_pll_init(), fixing the
> issue. This is is just a quick hack to get the OMAP2_DSS_USE_DSI_PLL
> option working. There shouldn't be any other downside in this solution
> than some extra lines of code.
>
> OMAP2_DSS_USE_DSI_PLL is itself a big hack, and should be removed, and
> the feature itself should be implemented in a more sane way. However,
> the solution is not trivial, and people are using DSI PLL to get more
> exact pixel clocks, so this hack is an acceptable temporary solution for
> the time being.
>
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
> ---
> drivers/video/omap2/dss/dsi.c | 20 ++++++++++++++++++++
> 1 files changed, 20 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/video/omap2/dss/dsi.c b/drivers/video/omap2/dss/dsi.c
> index c3019d9..6f4f19d 100644
> --- a/drivers/video/omap2/dss/dsi.c
> +++ b/drivers/video/omap2/dss/dsi.c
> @@ -1105,6 +1105,26 @@ int dsi_pll_init(struct omap_dss_device *dssdev, bool enable_hsclk,
>
> DSSDBG("PLL init\n");
>
> +#ifdef CONFIG_OMAP2_DSS_USE_DSI_PLL
> + /*
> + * HACK: this is just a quick hack to get the USE_DSI_PLL
> + * option working. USE_DSI_PLL is itself a big hack, and
> + * should be removed.
> + */
> + if (dsi.vdds_dsi_reg == NULL) {
> + struct regulator *vdds_dsi;
> +
> + vdds_dsi = regulator_get(&dsi.pdev->dev, "vdds_dsi");
> +
> + if (IS_ERR(vdds_dsi)) {
> + DSSERR("can't get VDDS_DSI regulator\n");
> + return PTR_ERR(vdds_dsi);
> + }
> +
> + dsi.vdds_dsi_reg = vdds_dsi;
> + }
> +#endif
> +
> enable_clocks(1);
> dsi_enable_pll_clock(1);
>
The hack might be temporarily acceptable.
But I think there should be a matching regulator_put in dsi_pll_uinit.
> --
> 1.7.1
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
