ARM: 6981/2: mmci: adjust calculation of f_min

The ARM version maximum clock divider is 512 whereas for the ST
variants it's 257. Let's use DIV_ROUND_UP() for both cases so we
can see clearly what's going on here.

[Use DIV_ROUND_UP to clarify elder code]

Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com>
Reviewed-by: Sebastian Rasmussen <sebastian.rasmussen@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 9 insertions, 1 deletions

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 7721de942c6..c471cdb1a0b 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -1061,7 +1061,15 @@ static int __devinit mmci_probe(struct amba_device *dev,
         }
 
         mmc->ops = &mmci_ops;
-        mmc->f_min = (host->mclk + 511) / 512;
+        /*
+         * The ARM and ST versions of the block have slightly different
+         * clock divider equations which means that the minimum divider
+         * differs too.
+         */
+        if (variant->st_clkdiv)
+                mmc->f_min = DIV_ROUND_UP(host->mclk, 257);
+        else
+                mmc->f_min = DIV_ROUND_UP(host->mclk, 512);
         /*
          * If the platform data supplies a maximum operating
          * frequency, this takes precedence. Else, we fall back