mmc: sdhci: Add support for disabling clock

This patch adds support to disable clock if clk_disable
was set and then enable or set clock if the clock was changed
or clock was disabled when clock needs to be enabled.

Signed-off-by: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

drivers/mmc/sdhci.c

@@ -439,6 +439,9 @@ static int sdhci_set_ios(struct mmc *mmc)
 	if (mmc->clock != host->clock)
 		sdhci_set_clock(mmc, mmc->clock);
 
+	if (mmc->clk_disable)
+		sdhci_set_clock(mmc, 0);
+
 	/* Set bus width */
 	ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
 	if (mmc->bus_width == 8) {