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OMAPDSS: fix rounding when calculating fclk rate
authorTomi Valkeinen <tomi.valkeinen@ti.com>
Thu, 13 Feb 2014 09:36:22 +0000 (11:36 +0200)
committerTomi Valkeinen <tomi.valkeinen@ti.com>
Mon, 14 Apr 2014 11:52:08 +0000 (14:52 +0300)
"clk: divider: fix rate calculation for fractional rates" patch (and
similar for TI specific divider) fixes the clk-divider's rounding. This
patch updates the DSS driver to round the rates accordingly.

This fixes the DSS's warnings about clock rate mismatch, and also fixes
the wrong fclk rate being set.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Tested-by: Christoph Fritz <chf.fritz@googlemail.com>
Tested-by: Marek Belisko <marek@goldelico.com>
drivers/video/omap2/dss/dss.c

index 825c019..d55266c 100644 (file)
@@ -457,7 +457,7 @@ bool dss_div_calc(unsigned long pck, unsigned long fck_min,
        fckd_stop = max(DIV_ROUND_UP(prate * m, fck_hw_max), 1ul);
 
        for (fckd = fckd_start; fckd >= fckd_stop; --fckd) {
-               fck = prate / fckd * m;
+               fck = DIV_ROUND_UP(prate, fckd) * m;
 
                if (func(fck, data))
                        return true;
@@ -506,7 +506,7 @@ static int dss_setup_default_clock(void)
 
                fck_div = DIV_ROUND_UP(prate * dss.feat->dss_fck_multiplier,
                                max_dss_fck);
-               fck = prate / fck_div * dss.feat->dss_fck_multiplier;
+               fck = DIV_ROUND_UP(prate, fck_div) * dss.feat->dss_fck_multiplier;
        }
 
        r = dss_set_fck_rate(fck);