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>
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 5eac21d..e6d7d9f 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -59,7 +59,7 @@
 /*
  * Given the decoded CSD structure, decode the raw CID to our CID structure.
  */
-static void mmc_decode_cid(struct mmc_card *card)
+void mmc_decode_cid(struct mmc_card *card)
 {
 	u32 *resp = card->raw_cid;
 
@@ -238,7 +238,7 @@
 /*
  * Test if the card supports high-speed mode and, if so, switch to it.
  */
-static int mmc_switch_hs(struct mmc_card *card)
+int mmc_sd_switch_hs(struct mmc_card *card)
 {
 	int err;
 	u8 *status;
@@ -272,9 +272,9 @@
 		printk(KERN_WARNING "%s: Problem switching card "
 			"into high-speed mode!\n",
 			mmc_hostname(card->host));
+		err = 0;
 	} else {
-		mmc_card_set_highspeed(card);
-		mmc_set_timing(card->host, MMC_TIMING_SD_HS);
+		err = 1;
 	}
 
 out:
@@ -320,26 +320,16 @@
 	NULL,
 };
 
-static struct device_type sd_type = {
+struct device_type sd_type = {
 	.groups = sd_attr_groups,
 };
 
 /*
- * Handle the detection and initialisation of a card.
- *
- * In the case of a resume, "oldcard" will contain the card
- * we're trying to reinitialise.
+ * Fetch CID from card.
  */
-static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
-	struct mmc_card *oldcard)
+int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid)
 {
-	struct mmc_card *card;
 	int err;
-	u32 cid[4];
-	unsigned int max_dtr;
-
-	BUG_ON(!host);
-	WARN_ON(!host->claimed);
 
 	/*
 	 * Since we're changing the OCR value, we seem to
@@ -361,92 +351,57 @@
 
 	err = mmc_send_app_op_cond(host, ocr, NULL);
 	if (err)
-		goto err;
+		return err;
 
-	/*
-	 * Fetch CID from card.
-	 */
 	if (mmc_host_is_spi(host))
 		err = mmc_send_cid(host, cid);
 	else
 		err = mmc_all_send_cid(host, cid);
+
+	return err;
+}
+
+int mmc_sd_get_csd(struct mmc_host *host, struct mmc_card *card)
+{
+	int err;
+
+	/*
+	 * Fetch CSD from card.
+	 */
+	err = mmc_send_csd(card, card->raw_csd);
 	if (err)
-		goto err;
+		return err;
 
-	if (oldcard) {
-		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) {
-			err = -ENOENT;
-			goto err;
-		}
+	err = mmc_decode_csd(card);
+	if (err)
+		return err;
 
-		card = oldcard;
-	} else {
-		/*
-		 * Allocate card structure.
-		 */
-		card = mmc_alloc_card(host, &sd_type);
-		if (IS_ERR(card)) {
-			err = PTR_ERR(card);
-			goto err;
-		}
+	return 0;
+}
 
-		card->type = MMC_TYPE_SD;
-		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
-	}
+int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
+	bool reinit)
+{
+	int err;
 
-	/*
-	 * For native busses:  get card RCA and quit open drain mode.
-	 */
-	if (!mmc_host_is_spi(host)) {
-		err = mmc_send_relative_addr(host, &card->rca);
-		if (err)
-			goto free_card;
-
-		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
-	}
-
-	if (!oldcard) {
-		/*
-		 * Fetch CSD from card.
-		 */
-		err = mmc_send_csd(card, card->raw_csd);
-		if (err)
-			goto free_card;
-
-		err = mmc_decode_csd(card);
-		if (err)
-			goto free_card;
-
-		mmc_decode_cid(card);
-	}
-
-	/*
-	 * Select card, as all following commands rely on that.
-	 */
-	if (!mmc_host_is_spi(host)) {
-		err = mmc_select_card(card);
-		if (err)
-			goto free_card;
-	}
-
-	if (!oldcard) {
+	if (!reinit) {
 		/*
 		 * Fetch SCR from card.
 		 */
 		err = mmc_app_send_scr(card, card->raw_scr);
 		if (err)
-			goto free_card;
+			return err;
 
 		err = mmc_decode_scr(card);
-		if (err < 0)
-			goto free_card;
+		if (err)
+			return err;
 
 		/*
 		 * Fetch switch information from card.
 		 */
 		err = mmc_read_switch(card);
 		if (err)
-			goto free_card;
+			return err;
 	}
 
 	/*
@@ -458,20 +413,34 @@
 	if (mmc_host_is_spi(host)) {
 		err = mmc_spi_set_crc(host, use_spi_crc);
 		if (err)
-			goto free_card;
+			return err;
 	}
 
 	/*
-	 * Attempt to change to high-speed (if supported)
+	 * Check if read-only switch is active.
 	 */
-	err = mmc_switch_hs(card);
-	if (err)
-		goto free_card;
+	if (!reinit) {
+		int ro = -1;
 
-	/*
-	 * Compute bus speed.
-	 */
-	max_dtr = (unsigned int)-1;
+		if (host->ops->get_ro)
+			ro = host->ops->get_ro(host);
+
+		if (ro < 0) {
+			printk(KERN_WARNING "%s: host does not "
+				"support reading read-only "
+				"switch. assuming write-enable.\n",
+				mmc_hostname(host));
+		} else if (ro > 0) {
+			mmc_card_set_readonly(card);
+		}
+	}
+
+	return 0;
+}
+
+unsigned mmc_sd_get_max_clock(struct mmc_card *card)
+{
+	unsigned max_dtr = (unsigned int)-1;
 
 	if (mmc_card_highspeed(card)) {
 		if (max_dtr > card->sw_caps.hs_max_dtr)
@@ -480,7 +449,97 @@
 		max_dtr = card->csd.max_dtr;
 	}
 
-	mmc_set_clock(host, max_dtr);
+	return max_dtr;
+}
+
+void mmc_sd_go_highspeed(struct mmc_card *card)
+{
+	mmc_card_set_highspeed(card);
+	mmc_set_timing(card->host, MMC_TIMING_SD_HS);
+}
+
+/*
+ * Handle the detection and initialisation of a card.
+ *
+ * In the case of a resume, "oldcard" will contain the card
+ * we're trying to reinitialise.
+ */
+static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
+	struct mmc_card *oldcard)
+{
+	struct mmc_card *card;
+	int err;
+	u32 cid[4];
+
+	BUG_ON(!host);
+	WARN_ON(!host->claimed);
+
+	err = mmc_sd_get_cid(host, ocr, cid);
+	if (err)
+		return err;
+
+	if (oldcard) {
+		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0)
+			return -ENOENT;
+
+		card = oldcard;
+	} else {
+		/*
+		 * Allocate card structure.
+		 */
+		card = mmc_alloc_card(host, &sd_type);
+		if (IS_ERR(card))
+			return PTR_ERR(card);
+
+		card->type = MMC_TYPE_SD;
+		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
+	}
+
+	/*
+	 * For native busses:  get card RCA and quit open drain mode.
+	 */
+	if (!mmc_host_is_spi(host)) {
+		err = mmc_send_relative_addr(host, &card->rca);
+		if (err)
+			return err;
+
+		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
+	}
+
+	if (!oldcard) {
+		err = mmc_sd_get_csd(host, card);
+		if (err)
+			return err;
+
+		mmc_decode_cid(card);
+	}
+
+	/*
+	 * Select card, as all following commands rely on that.
+	 */
+	if (!mmc_host_is_spi(host)) {
+		err = mmc_select_card(card);
+		if (err)
+			return err;
+	}
+
+	err = mmc_sd_setup_card(host, card, oldcard != NULL);
+	if (err)
+		goto free_card;
+
+	/*
+	 * Attempt to change to high-speed (if supported)
+	 */
+	err = mmc_sd_switch_hs(card);
+	if (err > 0)
+		mmc_sd_go_highspeed(card);
+	else if (err)
+		goto free_card;
+
+	/*
+	 * Set bus speed.
+	 */
+	mmc_set_clock(host, mmc_sd_get_max_clock(card));
 
 	/*
 	 * Switch to wider bus (if supported).
@@ -494,30 +553,12 @@
 		mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
 	}
 
-	/*
-	 * Check if read-only switch is active.
-	 */
-	if (!oldcard) {
-		if (!host->ops->get_ro || host->ops->get_ro(host) < 0) {
-			printk(KERN_WARNING "%s: host does not "
-				"support reading read-only "
-				"switch. assuming write-enable.\n",
-				mmc_hostname(host));
-		} else {
-			if (host->ops->get_ro(host) > 0)
-				mmc_card_set_readonly(card);
-		}
-	}
-
-	if (!oldcard)
-		host->card = card;
-
+	host->card = card;
 	return 0;
 
 free_card:
 	if (!oldcard)
 		mmc_remove_card(card);
-err:
 
 	return err;
 }
diff --git a/drivers/mmc/core/sd.h b/drivers/mmc/core/sd.h
new file mode 100644
index 0000000..3d8800f
--- /dev/null
+++ b/drivers/mmc/core/sd.h
@@ -0,0 +1,17 @@
+#ifndef _MMC_CORE_SD_H
+#define _MMC_CORE_SD_H
+
+#include <linux/mmc/card.h>
+
+extern struct device_type sd_type;
+
+int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid);
+int mmc_sd_get_csd(struct mmc_host *host, struct mmc_card *card);
+void mmc_decode_cid(struct mmc_card *card);
+int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
+	bool reinit);
+unsigned mmc_sd_get_max_clock(struct mmc_card *card);
+int mmc_sd_switch_hs(struct mmc_card *card);
+void mmc_sd_go_highspeed(struct mmc_card *card);
+
+#endif
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index b9dee28..47d1708 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 @@
 	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 @@
 	 * 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).