mmc: core: add comment why sdio_reset is done at init time

Commit Message

Philip Rakity Feb. 14, 2011, 7:12 a.m. UTC

None

Patch

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 34a7e8c..d9fb0d3 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1494,6 +1494,12 @@  static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 		mmc_hostname(host), __func__, host->f_init);
 #endif
 	mmc_power_up(host);
+
+	/*
+	 * sdio_reset sends CMD52 to reset card.  Since we do not know
+	 * if the card is being re-initialzed just send it.  CMD52
+	 * should be ignored by SD/eMMC cards
+	 */
 	sdio_reset(host);
 	mmc_go_idle(host);