* [PATCH] mmci: adjust calculation of f_min
@ 2011-07-07 20:27 Linus Walleij
0 siblings, 0 replies; only message in thread
From: Linus Walleij @ 2011-07-07 20:27 UTC (permalink / raw)
To: linux-arm-kernel
From: Ulf Hansson <ulf.hansson@stericsson.com>
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.
Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com>
Reviewed-by: Sebastian Rasmussen <sebastian.rasmussen@stericsson.com>
[Use DIV_ROUND_UP to clarify elder code]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/mmc/host/mmci.c | 10 +++++++++-
1 files changed, 9 insertions(+), 1 deletions(-)
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index fe14072..50f4f77 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -1063,7 +1063,15 @@ 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
--
1.7.6
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