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    SubjectRe: [PATCH] fbdev/omap: fix max fclk divider for omap36xx
    On Mon, Oct 21, 2019 at 3:42 AM Tomi Valkeinen <tomi.valkeinen@ti.com> wrote:
    >
    > On 18/10/2019 15:49, Adam Ford wrote:
    > > The OMAP36xx and AM/DM37x TRMs say that the maximum divider for DSS fclk
    > > (in CM_CLKSEL_DSS) is 32. Experimentation shows that this is not
    > > correct, and using divider of 32 breaks DSS with a flood or underflows
    > > and sync losts. Dividers up to 31 seem to work fine.
    > >
    > > There is another patch to the DT files to limit the divider correctly,
    > > but as the DSS driver also needs to know the maximum divider to be able
    > > to iteratively find good rates, we also need to do the fix in the DSS
    > > driver.
    > >
    > > Signed-off-by: Adam Ford <aford173@gmail.com>
    > > Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
    > > Cc: stable@vger.kernel.org #linux-4.9.y+
    > >
    > > diff --git a/drivers/video/fbdev/omap2/omapfb/dss/dss.c b/drivers/video/fbdev/omap2/omapfb/dss/dss.c
    > > index 48c6500c24e1..4429ad37b64c 100644
    > > --- a/drivers/video/fbdev/omap2/omapfb/dss/dss.c
    > > +++ b/drivers/video/fbdev/omap2/omapfb/dss/dss.c
    > > @@ -843,7 +843,7 @@ static const struct dss_features omap34xx_dss_feats = {
    > > };
    > >
    > > static const struct dss_features omap3630_dss_feats = {
    > > - .fck_div_max = 32,
    > > + .fck_div_max = 31,
    > > .dss_fck_multiplier = 1,
    > > .parent_clk_name = "dpll4_ck",
    > > .dpi_select_source = &dss_dpi_select_source_omap2_omap3,
    > >
    >
    > Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

    What is the next step to get these integrated into 4.9+?

    adam
    >
    > Tomi
    >
    > --
    > Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
    > Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

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