sdhci-of: fix SD clock calculation

Linear divisor's values in a register start at 0 (zero means "divide by
1").  Before this patch the code didn't account that fact, so SD cards
were running underclocked.

Signed-off-by: Anton Vorontsov <[email protected]>
Cc: Pierre Ossman <[email protected]>
Cc: Kumar Gala <[email protected]>
Cc: David Vrabel <[email protected]>
Cc: Ben Dooks <[email protected]>
Cc: Sascha Hauer <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/drivers/mmc/host/sdhci-of.c b/drivers/mmc/host/sdhci-of.c
index 1e8aa590bb39b0a5e650037f61647860fd2b3ec1..2b0756934f49e119553437c77ab9d71bd97eecd3 100644 (file)
--- a/drivers/mmc/host/sdhci-of.c
+++ b/drivers/mmc/host/sdhci-of.c
@@ -136,6 +136,7 @@ static void esdhc_set_clock(struct sdhci_host *host, unsigned int clock)
        }
 
        pre_div >>= 1;
+       div--;
 
        setbits32(host->ioaddr + ESDHC_SYSTEM_CONTROL, ESDHC_CLOCK_IPGEN |
                  ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN |