mmc: split mmc_sd_init_card()

This series adds support for SD combo cards to MMC/SD driver stack.

SD combo consists of SD memory and SDIO parts in one package.  Since the
parts have a separate SD command sets, after initialization, they can be
treated as independent cards on one bus.

Changes are divided into two patches.  First is just moving initialization
code around so that SD memory part init can be called from SDIO init.
Second patch is a proper change enabling SD memory along SDIO.  I tried to
move as much no-op changes to the first patch so that it's easier to
follow the required changes to initialization flow for SDIO cards.

This is based on Simplified SDIO spec v.2.00.  The init sequence is
slightly modified to follow current SD memory init implementation.
Command sequences, assuming SD memory and SDIO indeed ignore unknown
commands, are the same as before for both parts.

This patch:

Prepare for SD-combo (IO+mem) support by splitting SD memory
card init and related functions.

Signed-off-by: Michal Miroslaw <mirq-linux@rere.qmqm.pl>
Cc: Adrian Hunter <adrian.hunter@nokia.com>
Cc: Chris Ball <cjb@laptop.org>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 24 insertions, 15 deletions

diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index b9dee28ee7d0..47d1708810bd 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -18,6 +18,7 @@
 
 #include "core.h"
 #include "bus.h"
+#include "sd.h"
 #include "sdio_bus.h"
 #include "mmc_ops.h"
 #include "sd_ops.h"
@@ -245,10 +246,26 @@ static int sdio_enable_hs(struct mmc_card *card)
 	if (ret)
 		return ret;
 
-	mmc_card_set_highspeed(card);
-	mmc_set_timing(card->host, MMC_TIMING_SD_HS);
+	return 1;
+}
 
-	return 0;
+static unsigned mmc_sdio_get_max_clock(struct mmc_card *card)
+{
+	unsigned max_dtr;
+
+	if (mmc_card_highspeed(card)) {
+		/*
+		 * The SDIO specification doesn't mention how
+		 * the CIS transfer speed register relates to
+		 * high-speed, but it seems that 50 MHz is
+		 * mandatory.
+		 */
+		max_dtr = 50000000;
+	} else {
+		max_dtr = card->cis.max_dtr;
+	}
+
+	return max_dtr;
 }
 
 /*
@@ -351,23 +368,15 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
 	 * Switch to high-speed (if supported).
 	 */
 	err = sdio_enable_hs(card);
-	if (err)
+	if (err > 0)
+		mmc_sd_go_highspeed(card);
+	else if (err)
 		goto remove;
 
 	/*
 	 * Change to the card's maximum speed.
 	 */
-	if (mmc_card_highspeed(card)) {
-		/*
-		 * The SDIO specification doesn't mention how
-		 * the CIS transfer speed register relates to
-		 * high-speed, but it seems that 50 MHz is
-		 * mandatory.
-		 */
-		mmc_set_clock(host, 50000000);
-	} else {
-		mmc_set_clock(host, card->cis.max_dtr);
-	}
+	mmc_set_clock(host, mmc_sdio_get_max_clock(card));
 
 	/*
 	 * Switch to wider bus (if supported).