[PATCH 5.7 18/79] omapfb: dss: Fix max fclk divider for omap36xx

Greg Kroah-Hartman
2020-08-10T15:42:03Z

From: Adam Ford <aford173@gmail.com>

commit 254503a2b186caa668a188dbbd7ab0d25149c0a5 upstream.

The drm/omap driver was fixed to correct an issue where using a
divider of 32 breaks the DSS despite the TRM stating 32 is a valid
number. Through experimentation, it appears that 31 works, and
it is consistent with the value used by the drm/omap driver.

This patch fixes the divider for fbdev driver instead of the drm.

Fixes: f76ee892a99e ("omapfb: copy omapdss & displays for omapfb")
Cc: <stable@vger.kernel.org> #4.5+
Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Rob Clark <robdclark@gmail.com>
[b.zolnierkie: mark patch as applicable to stable 4.5+ (was 4.9+)]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200630182636.439015-1-aford173@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/video/fbdev/omap2/omapfb/dss/dss.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/video/fbdev/omap2/omapfb/dss/dss.c
+++ b/drivers/video/fbdev/omap2/omapfb/dss/dss.c
@@ -833,7 +833,7 @@ static const struct dss_features omap34x
};

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,