mmc: sdhci: programmable clock calculation needs multiplier +1
According to the SD Host Controller Simplified Specification v4.20,
the multiplier value M is one more than the Clock Multiplier field.
Copied code from Linux project. drivers/mmc/host/sdhci.c line 4405
Signed-off-by: cmachida <curtis.machida@intel.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Sean Anderson <sean.anderson@seco.com>
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index ceeac32..af654ea 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -930,6 +930,15 @@
debug("%s, caps_1: 0x%x\n", __func__, caps_1);
host->clk_mul = (caps_1 & SDHCI_CLOCK_MUL_MASK) >>
SDHCI_CLOCK_MUL_SHIFT;
+
+ /*
+ * In case the value in Clock Multiplier is 0, then programmable
+ * clock mode is not supported, otherwise the actual clock
+ * multiplier is one more than the value of Clock Multiplier
+ * in the Capabilities Register.
+ */
+ if (host->clk_mul)
+ host->clk_mul += 1;
}
if (host->max_clk == 0) {