mmc: add a new mmc parameter to disable mmc clock

mmc clock has to be disabled in certain cases like during
the voltage switch sequence. Modify mmc_set_clock function
to take disable as an argument that signifies if the
clock has to be enabled or disabled.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 0ffe7bf..664b71a 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -1214,7 +1214,7 @@
 }
 #endif
 
-int mmc_set_clock(struct mmc *mmc, uint clock)
+int mmc_set_clock(struct mmc *mmc, uint clock, bool disable)
 {
 	if (clock > mmc->cfg->f_max)
 		clock = mmc->cfg->f_max;
@@ -1223,6 +1223,7 @@
 		clock = mmc->cfg->f_min;
 
 	mmc->clock = clock;
+	mmc->clk_disable = disable;
 
 	return mmc_set_ios(mmc);
 }
@@ -1322,7 +1323,7 @@
 
 				/* configure the bus mode (host) */
 				mmc_select_mode(mmc, mwt->mode);
-				mmc_set_clock(mmc, mmc->tran_speed);
+				mmc_set_clock(mmc, mmc->tran_speed, false);
 
 				err = sd_read_ssr(mmc);
 				if (!err)
@@ -1333,7 +1334,7 @@
 error:
 				/* revert to a safer bus speed */
 				mmc_select_mode(mmc, SD_LEGACY);
-				mmc_set_clock(mmc, mmc->tran_speed);
+				mmc_set_clock(mmc, mmc->tran_speed, false);
 			}
 		}
 	}
@@ -1476,7 +1477,7 @@
 
 			/* configure the bus mode (host) */
 			mmc_select_mode(mmc, mwt->mode);
-			mmc_set_clock(mmc, mmc->tran_speed);
+			mmc_set_clock(mmc, mmc->tran_speed, false);
 
 			/* do a transfer to check the configuration */
 			err = mmc_read_and_compare_ext_csd(mmc);
@@ -1950,7 +1951,7 @@
 
 	mmc_select_mode(mmc, MMC_LEGACY);
 	mmc_set_bus_width(mmc, 1);
-	mmc_set_clock(mmc, 0);
+	mmc_set_clock(mmc, 0, false);
 }
 
 static int mmc_power_on(struct mmc *mmc)