Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc:
  mmc: at91_mci: fix hanging and rework to match flowcharts
  mmc: at91_mci typo
  sdhci: Fix "Unexpected interrupt" handling
  mmc: fix silly copy-and-paste error
  mmc: move layer init and workqueue to core file
  mmc: refactor host class handling
  mmc: refactor bus operations
  sdhci: add ene controller id
  mmc: bounce requests for simple hosts

18 files changed, 980 insertions, 572 deletions

diff --git a/drivers/mmc/card/Kconfig b/drivers/mmc/card/Kconfig
index 9320a8c7323..a49cb9737cd 100644
--- a/drivers/mmc/card/Kconfig
+++ b/drivers/mmc/card/Kconfig
@@ -14,3 +14,21 @@ config MMC_BLOCK
 	  mount the filesystem. Almost everyone wishing MMC support
 	  should say Y or M here.
 
+config MMC_BLOCK_BOUNCE
+	bool "Use bounce buffer for simple hosts"
+	depends on MMC_BLOCK
+	default y
+	help
+	  SD/MMC is a high latency protocol where it is crucial to
+	  send large requests in order to get high performance. Many
+	  controllers, however, are restricted to continuous memory
+	  (i.e. they can't do scatter-gather), something the kernel
+	  rarely can provide.
+
+	  Say Y here to help these restricted hosts by bouncing
+	  requests back and forth from a large buffer. You will get
+	  a big performance gain at the cost of up to 64 KiB of
+	  physical memory.
+
+	  If unsure, say Y here.
+
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 540ff4bea54..cbd4b6e3e17 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -262,7 +262,9 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 		}
 
 		brq.data.sg = mq->sg;
-		brq.data.sg_len = blk_rq_map_sg(req->q, req, brq.data.sg);
+		brq.data.sg_len = mmc_queue_map_sg(mq);
+
+		mmc_queue_bounce_pre(mq);
 
 		if (brq.data.blocks !=
 		    (req->nr_sectors >> (md->block_bits - 9))) {
@@ -279,6 +281,9 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 		}
 
 		mmc_wait_for_req(card->host, &brq.mrq);
+
+		mmc_queue_bounce_post(mq);
+
 		if (brq.cmd.error) {
 			printk(KERN_ERR "%s: error %d sending read/write command\n",
 			       req->rq_disk->disk_name, brq.cmd.error);
diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
index dd97bc79840..4fb2089dc69 100644
--- a/drivers/mmc/card/queue.c
+++ b/drivers/mmc/card/queue.c
@@ -17,6 +17,8 @@
 #include <linux/mmc/host.h>
 #include "queue.h"
 
+#define MMC_QUEUE_BOUNCESZ	65536
+
 #define MMC_QUEUE_SUSPENDED	(1 << 0)
 
 /*
@@ -118,6 +120,7 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock
 	struct mmc_host *host = card->host;
 	u64 limit = BLK_BOUNCE_HIGH;
 	int ret;
+	unsigned int bouncesz;
 
 	if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
 		limit = *mmc_dev(host)->dma_mask;
@@ -127,21 +130,61 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock
 	if (!mq->queue)
 		return -ENOMEM;
 
-	blk_queue_prep_rq(mq->queue, mmc_prep_request);
-	blk_queue_bounce_limit(mq->queue, limit);
-	blk_queue_max_sectors(mq->queue, host->max_req_size / 512);
-	blk_queue_max_phys_segments(mq->queue, host->max_phys_segs);
-	blk_queue_max_hw_segments(mq->queue, host->max_hw_segs);
-	blk_queue_max_segment_size(mq->queue, host->max_seg_size);
-
 	mq->queue->queuedata = mq;
 	mq->req = NULL;
 
-	mq->sg = kmalloc(sizeof(struct scatterlist) * host->max_phys_segs,
-			 GFP_KERNEL);
-	if (!mq->sg) {
-		ret = -ENOMEM;
-		goto cleanup_queue;
+	blk_queue_prep_rq(mq->queue, mmc_prep_request);
+
+#ifdef CONFIG_MMC_BLOCK_BOUNCE
+	if (host->max_hw_segs == 1) {
+		bouncesz = MMC_QUEUE_BOUNCESZ;
+
+		if (bouncesz > host->max_req_size)
+			bouncesz = host->max_req_size;
+		if (bouncesz > host->max_seg_size)
+			bouncesz = host->max_seg_size;
+
+		mq->bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
+		if (!mq->bounce_buf) {
+			printk(KERN_WARNING "%s: unable to allocate "
+				"bounce buffer\n", mmc_card_name(card));
+		} else {
+			blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_HIGH);
+			blk_queue_max_sectors(mq->queue, bouncesz / 512);
+			blk_queue_max_phys_segments(mq->queue, bouncesz / 512);
+			blk_queue_max_hw_segments(mq->queue, bouncesz / 512);
+			blk_queue_max_segment_size(mq->queue, bouncesz);
+
+			mq->sg = kmalloc(sizeof(struct scatterlist),
+				GFP_KERNEL);
+			if (!mq->sg) {
+				ret = -ENOMEM;
+				goto free_bounce_buf;
+			}
+
+			mq->bounce_sg = kmalloc(sizeof(struct scatterlist) *
+				bouncesz / 512, GFP_KERNEL);
+			if (!mq->bounce_sg) {
+				ret = -ENOMEM;
+				goto free_sg;
+			}
+		}
+	}
+#endif
+
+	if (!mq->bounce_buf) {
+		blk_queue_bounce_limit(mq->queue, limit);
+		blk_queue_max_sectors(mq->queue, host->max_req_size / 512);
+		blk_queue_max_phys_segments(mq->queue, host->max_phys_segs);
+		blk_queue_max_hw_segments(mq->queue, host->max_hw_segs);
+		blk_queue_max_segment_size(mq->queue, host->max_seg_size);
+
+		mq->sg = kmalloc(sizeof(struct scatterlist) *
+			host->max_phys_segs, GFP_KERNEL);
+		if (!mq->sg) {
+			ret = -ENOMEM;
+			goto cleanup_queue;
+		}
 	}
 
 	init_MUTEX(&mq->thread_sem);
@@ -149,14 +192,21 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock
 	mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd");
 	if (IS_ERR(mq->thread)) {
 		ret = PTR_ERR(mq->thread);
-		goto free_sg;
+		goto free_bounce_sg;
 	}
 
 	return 0;
-
+ free_bounce_sg:
+ 	if (mq->bounce_sg)
+ 		kfree(mq->bounce_sg);
+ 	mq->bounce_sg = NULL;
  free_sg:
 	kfree(mq->sg);
 	mq->sg = NULL;
+ free_bounce_buf:
+	if (mq->bounce_buf)
+		kfree(mq->bounce_buf);
+	mq->bounce_buf = NULL;
  cleanup_queue:
 	blk_cleanup_queue(mq->queue);
 	return ret;
@@ -178,9 +228,17 @@ void mmc_cleanup_queue(struct mmc_queue *mq)
 	/* Then terminate our worker thread */
 	kthread_stop(mq->thread);
 
+ 	if (mq->bounce_sg)
+ 		kfree(mq->bounce_sg);
+ 	mq->bounce_sg = NULL;
+
 	kfree(mq->sg);
 	mq->sg = NULL;
 
+	if (mq->bounce_buf)
+		kfree(mq->bounce_buf);
+	mq->bounce_buf = NULL;
+
 	blk_cleanup_queue(mq->queue);
 
 	mq->card = NULL;
@@ -231,3 +289,108 @@ void mmc_queue_resume(struct mmc_queue *mq)
 	}
 }
 
+static void copy_sg(struct scatterlist *dst, unsigned int dst_len,
+	struct scatterlist *src, unsigned int src_len)
+{
+	unsigned int chunk;
+	char *dst_buf, *src_buf;
+	unsigned int dst_size, src_size;
+
+	dst_buf = NULL;
+	src_buf = NULL;
+	dst_size = 0;
+	src_size = 0;
+
+	while (src_len) {
+		BUG_ON(dst_len == 0);
+
+		if (dst_size == 0) {
+			dst_buf = page_address(dst->page) + dst->offset;
+			dst_size = dst->length;
+		}
+
+		if (src_size == 0) {
+			src_buf = page_address(src->page) + src->offset;
+			src_size = src->length;
+		}
+
+		chunk = min(dst_size, src_size);
+
+		memcpy(dst_buf, src_buf, chunk);
+
+		dst_buf += chunk;
+		src_buf += chunk;
+		dst_size -= chunk;
+		src_size -= chunk;
+
+		if (dst_size == 0) {
+			dst++;
+			dst_len--;
+		}
+
+		if (src_size == 0) {
+			src++;
+			src_len--;
+		}
+	}
+}
+
+unsigned int mmc_queue_map_sg(struct mmc_queue *mq)
+{
+	unsigned int sg_len;
+
+	if (!mq->bounce_buf)
+		return blk_rq_map_sg(mq->queue, mq->req, mq->sg);
+
+	BUG_ON(!mq->bounce_sg);
+
+	sg_len = blk_rq_map_sg(mq->queue, mq->req, mq->bounce_sg);
+
+	mq->bounce_sg_len = sg_len;
+
+	/*
+	 * Shortcut in the event we only get a single entry.
+	 */
+	if (sg_len == 1) {
+		memcpy(mq->sg, mq->bounce_sg, sizeof(struct scatterlist));
+		return 1;
+	}
+
+	mq->sg[0].page = virt_to_page(mq->bounce_buf);
+	mq->sg[0].offset = offset_in_page(mq->bounce_buf);
+	mq->sg[0].length = 0;
+
+	while (sg_len) {
+		mq->sg[0].length += mq->bounce_sg[sg_len - 1].length;
+		sg_len--;
+	}
+
+	return 1;
+}
+
+void mmc_queue_bounce_pre(struct mmc_queue *mq)
+{
+	if (!mq->bounce_buf)
+		return;
+
+	if (mq->bounce_sg_len == 1)
+		return;
+	if (rq_data_dir(mq->req) != WRITE)
+		return;
+
+	copy_sg(mq->sg, 1, mq->bounce_sg, mq->bounce_sg_len);
+}
+
+void mmc_queue_bounce_post(struct mmc_queue *mq)
+{
+	if (!mq->bounce_buf)
+		return;
+
+	if (mq->bounce_sg_len == 1)
+		return;
+	if (rq_data_dir(mq->req) != READ)
+		return;
+
+	copy_sg(mq->bounce_sg, mq->bounce_sg_len, mq->sg, 1);
+}
+
diff --git a/drivers/mmc/card/queue.h b/drivers/mmc/card/queue.h
index 1590b3f3f1f..64e66e0d499 100644
--- a/drivers/mmc/card/queue.h
+++ b/drivers/mmc/card/queue.h
@@ -14,6 +14,9 @@ struct mmc_queue {
 	void			*data;
 	struct request_queue	*queue;
 	struct scatterlist	*sg;
+	char			*bounce_buf;
+	struct scatterlist	*bounce_sg;
+	unsigned int		bounce_sg_len;
 };
 
 extern int mmc_init_queue(struct mmc_queue *, struct mmc_card *, spinlock_t *);
@@ -21,4 +24,8 @@ extern void mmc_cleanup_queue(struct mmc_queue *);
 extern void mmc_queue_suspend(struct mmc_queue *);
 extern void mmc_queue_resume(struct mmc_queue *);
 
+extern unsigned int mmc_queue_map_sg(struct mmc_queue *);
+extern void mmc_queue_bounce_pre(struct mmc_queue *);
+extern void mmc_queue_bounce_post(struct mmc_queue *);
+
 #endif
diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile
index 1075b02ae75..3fdd08c7f14 100644
--- a/drivers/mmc/core/Makefile
+++ b/drivers/mmc/core/Makefile
@@ -7,5 +7,6 @@ ifeq ($(CONFIG_MMC_DEBUG),y)
 endif
 
 obj-$(CONFIG_MMC)		+= mmc_core.o
-mmc_core-y			:= core.o sysfs.o mmc.o mmc_ops.o sd.o sd_ops.o
+mmc_core-y			:= core.o sysfs.o bus.o host.o \
+				   mmc.o mmc_ops.o sd.o sd_ops.o
 
diff --git a/drivers/mmc/core/bus.c b/drivers/mmc/core/bus.c
new file mode 100644
index 00000000000..348b566bf4f
--- /dev/null
+++ b/drivers/mmc/core/bus.c
@@ -0,0 +1,253 @@
+/*
+ *  linux/drivers/mmc/core/bus.c
+ *
+ *  Copyright (C) 2003 Russell King, All Rights Reserved.
+ *  Copyright (C) 2007 Pierre Ossman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  MMC card bus driver model
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+
+#include <linux/mmc/card.h>
+#include <linux/mmc/host.h>
+
+#include "sysfs.h"
+#include "core.h"
+#include "bus.h"
+
+#define dev_to_mmc_card(d)	container_of(d, struct mmc_card, dev)
+#define to_mmc_driver(d)	container_of(d, struct mmc_driver, drv)
+
+static ssize_t mmc_type_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct mmc_card *card = dev_to_mmc_card(dev);
+
+	switch (card->type) {
+	case MMC_TYPE_MMC:
+		return sprintf(buf, "MMC\n");
+	case MMC_TYPE_SD:
+		return sprintf(buf, "SD\n");
+	default:
+		return -EFAULT;
+	}
+}
+
+static struct device_attribute mmc_dev_attrs[] = {
+	MMC_ATTR_RO(type),
+	__ATTR_NULL,
+};
+
+/*
+ * This currently matches any MMC driver to any MMC card - drivers
+ * themselves make the decision whether to drive this card in their
+ * probe method.
+ */
+static int mmc_bus_match(struct device *dev, struct device_driver *drv)
+{
+	return 1;
+}
+
+static int
+mmc_bus_uevent(struct device *dev, char **envp, int num_envp, char *buf,
+		int buf_size)
+{
+	struct mmc_card *card = dev_to_mmc_card(dev);
+	int retval = 0, i = 0, length = 0;
+
+#define add_env(fmt,val) do {					\
+	retval = add_uevent_var(envp, num_envp, &i,		\
+				buf, buf_size, &length,		\
+				fmt, val);			\
+	if (retval)						\
+		return retval;					\
+} while (0);
+
+	switch (card->type) {
+	case MMC_TYPE_MMC:
+		add_env("MMC_TYPE=%s", "MMC");
+		break;
+	case MMC_TYPE_SD:
+		add_env("MMC_TYPE=%s", "SD");
+		break;
+	}
+
+	add_env("MMC_NAME=%s", mmc_card_name(card));
+
+#undef add_env
+
+	envp[i] = NULL;
+
+	return 0;
+}
+
+static int mmc_bus_probe(struct device *dev)
+{
+	struct mmc_driver *drv = to_mmc_driver(dev->driver);
+	struct mmc_card *card = dev_to_mmc_card(dev);
+
+	return drv->probe(card);
+}
+
+static int mmc_bus_remove(struct device *dev)
+{
+	struct mmc_driver *drv = to_mmc_driver(dev->driver);
+	struct mmc_card *card = dev_to_mmc_card(dev);
+
+	drv->remove(card);
+
+	return 0;
+}
+
+static int mmc_bus_suspend(struct device *dev, pm_message_t state)
+{
+	struct mmc_driver *drv = to_mmc_driver(dev->driver);
+	struct mmc_card *card = dev_to_mmc_card(dev);
+	int ret = 0;
+
+	if (dev->driver && drv->suspend)
+		ret = drv->suspend(card, state);
+	return ret;
+}
+
+static int mmc_bus_resume(struct device *dev)
+{
+	struct mmc_driver *drv = to_mmc_driver(dev->driver);
+	struct mmc_card *card = dev_to_mmc_card(dev);
+	int ret = 0;
+
+	if (dev->driver && drv->resume)
+		ret = drv->resume(card);
+	return ret;
+}
+
+static struct bus_type mmc_bus_type = {
+	.name		= "mmc",
+	.dev_attrs	= mmc_dev_attrs,
+	.match		= mmc_bus_match,
+	.uevent		= mmc_bus_uevent,
+	.probe		= mmc_bus_probe,
+	.remove		= mmc_bus_remove,
+	.suspend	= mmc_bus_suspend,
+	.resume		= mmc_bus_resume,
+};
+
+int mmc_register_bus(void)
+{
+	return bus_register(&mmc_bus_type);
+}
+
+void mmc_unregister_bus(void)
+{
+	bus_unregister(&mmc_bus_type);
+}
+
+/**
+ *	mmc_register_driver - register a media driver
+ *	@drv: MMC media driver
+ */
+int mmc_register_driver(struct mmc_driver *drv)
+{
+	drv->drv.bus = &mmc_bus_type;
+	return driver_register(&drv->drv);
+}
+
+EXPORT_SYMBOL(mmc_register_driver);
+
+/**
+ *	mmc_unregister_driver - unregister a media driver
+ *	@drv: MMC media driver
+ */
+void mmc_unregister_driver(struct mmc_driver *drv)
+{
+	drv->drv.bus = &mmc_bus_type;
+	driver_unregister(&drv->drv);
+}
+
+EXPORT_SYMBOL(mmc_unregister_driver);
+
+static void mmc_release_card(struct device *dev)
+{
+	struct mmc_card *card = dev_to_mmc_card(dev);
+
+	kfree(card);
+}
+
+/*
+ * Allocate and initialise a new MMC card structure.
+ */
+struct mmc_card *mmc_alloc_card(struct mmc_host *host)
+{
+	struct mmc_card *card;
+
+	card = kmalloc(sizeof(struct mmc_card), GFP_KERNEL);
+	if (!card)
+		return ERR_PTR(-ENOMEM);
+
+	memset(card, 0, sizeof(struct mmc_card));
+
+	card->host = host;
+
+	device_initialize(&card->dev);
+
+	card->dev.parent = mmc_classdev(host);
+	card->dev.bus = &mmc_bus_type;
+	card->dev.release = mmc_release_card;
+
+	return card;
+}
+
+/*
+ * Register a new MMC card with the driver model.
+ */
+int mmc_add_card(struct mmc_card *card)
+{
+	int ret;
+
+	snprintf(card->dev.bus_id, sizeof(card->dev.bus_id),
+		 "%s:%04x", mmc_hostname(card->host), card->rca);
+
+	card->dev.uevent_suppress = 1;
+
+	ret = device_add(&card->dev);
+	if (ret)
+		return ret;
+
+	if (card->host->bus_ops->sysfs_add) {
+		ret = card->host->bus_ops->sysfs_add(card->host, card);
+		if (ret) {
+			device_del(&card->dev);
+			return ret;
+		 }
+	}
+
+	card->dev.uevent_suppress = 0;
+
+	kobject_uevent(&card->dev.kobj, KOBJ_ADD);
+
+	mmc_card_set_present(card);
+
+	return 0;
+}
+
+/*
+ * Unregister a new MMC card with the driver model, and
+ * (eventually) free it.
+ */
+void mmc_remove_card(struct mmc_card *card)
+{
+	if (mmc_card_present(card)) {
+		if (card->host->bus_ops->sysfs_remove)
+			card->host->bus_ops->sysfs_remove(card->host, card);
+		device_del(&card->dev);
+	}
+
+	put_device(&card->dev);
+}
+
diff --git a/drivers/mmc/core/bus.h b/drivers/mmc/core/bus.h
new file mode 100644
index 00000000000..4f35431116a
--- /dev/null
+++ b/drivers/mmc/core/bus.h
@@ -0,0 +1,22 @@
+/*
+ *  linux/drivers/mmc/core/bus.h
+ *
+ *  Copyright (C) 2003 Russell King, All Rights Reserved.
+ *  Copyright 2007 Pierre Ossman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef _MMC_CORE_BUS_H
+#define _MMC_CORE_BUS_H
+
+struct mmc_card *mmc_alloc_card(struct mmc_host *host);
+int mmc_add_card(struct mmc_card *card);
+void mmc_remove_card(struct mmc_card *card);
+
+int mmc_register_bus(void);
+void mmc_unregister_bus(void);
+
+#endif
+
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 7385acfa1dd..b5d8a6d90cc 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -27,7 +27,8 @@
 #include <linux/mmc/sd.h>
 
 #include "core.h"
-#include "sysfs.h"
+#include "bus.h"
+#include "host.h"
 
 #include "mmc_ops.h"
 #include "sd_ops.h"
@@ -35,6 +36,25 @@
 extern int mmc_attach_mmc(struct mmc_host *host, u32 ocr);
 extern int mmc_attach_sd(struct mmc_host *host, u32 ocr);
 
+static struct workqueue_struct *workqueue;
+
+/*
+ * Internal function. Schedule delayed work in the MMC work queue.
+ */
+static int mmc_schedule_delayed_work(struct delayed_work *work,
+				     unsigned long delay)
+{
+	return queue_delayed_work(workqueue, work, delay);
+}
+
+/*
+ * Internal function. Flush all scheduled work from the MMC work queue.
+ */
+static void mmc_flush_scheduled_work(void)
+{
+	flush_workqueue(workqueue);
+}
+
 /**
  *	mmc_request_done - finish processing an MMC request
  *	@host: MMC host which completed request
@@ -369,22 +389,6 @@ void mmc_set_timing(struct mmc_host *host, unsigned int timing)
 }
 
 /*
- * Allocate a new MMC card
- */
-struct mmc_card *mmc_alloc_card(struct mmc_host *host)
-{
-	struct mmc_card *card;
-
-	card = kmalloc(sizeof(struct mmc_card), GFP_KERNEL);
-	if (!card)
-		return ERR_PTR(-ENOMEM);
-
-	mmc_init_card(card, host);
-
-	return card;
-}
-
-/*
  * Apply power to the MMC stack.  This is a two-stage process.
  * First, we enable power to the card without the clock running.
  * We then wait a bit for the power to stabilise.  Finally,
@@ -512,7 +516,7 @@ void mmc_detect_change(struct mmc_host *host, unsigned long delay)
 EXPORT_SYMBOL(mmc_detect_change);
 
 
-static void mmc_rescan(struct work_struct *work)
+void mmc_rescan(struct work_struct *work)
 {
 	struct mmc_host *host =
 		container_of(work, struct mmc_host, detect.work);
@@ -561,69 +565,13 @@ static void mmc_rescan(struct work_struct *work)
 	}
 }
 
-
-/**
- *	mmc_alloc_host - initialise the per-host structure.
- *	@extra: sizeof private data structure
- *	@dev: pointer to host device model structure
- *
- *	Initialise the per-host structure.
- */
-struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
+void mmc_start_host(struct mmc_host *host)
 {
-	struct mmc_host *host;
-
-	host = mmc_alloc_host_sysfs(extra, dev);
-	if (host) {
-		spin_lock_init(&host->lock);
-		init_waitqueue_head(&host->wq);
-		INIT_DELAYED_WORK(&host->detect, mmc_rescan);
-
-		/*
-		 * By default, hosts do not support SGIO or large requests.
-		 * They have to set these according to their abilities.
-		 */
-		host->max_hw_segs = 1;
-		host->max_phys_segs = 1;
-		host->max_seg_size = PAGE_CACHE_SIZE;
-
-		host->max_req_size = PAGE_CACHE_SIZE;
-		host->max_blk_size = 512;
-		host->max_blk_count = PAGE_CACHE_SIZE / 512;
-	}
-
-	return host;
-}
-
-EXPORT_SYMBOL(mmc_alloc_host);
-
-/**
- *	mmc_add_host - initialise host hardware
- *	@host: mmc host
- */
-int mmc_add_host(struct mmc_host *host)
-{
-	int ret;
-
-	ret = mmc_add_host_sysfs(host);
-	if (ret == 0) {
-		mmc_power_off(host);
-		mmc_detect_change(host, 0);
-	}
-
-	return ret;
+	mmc_power_off(host);
+	mmc_detect_change(host, 0);
 }
 
-EXPORT_SYMBOL(mmc_add_host);
-
-/**
- *	mmc_remove_host - remove host hardware
- *	@host: mmc host
- *
- *	Unregister and remove all cards associated with this host,
- *	and power down the MMC bus.
- */
-void mmc_remove_host(struct mmc_host *host)
+void mmc_stop_host(struct mmc_host *host)
 {
 #ifdef CONFIG_MMC_DEBUG
 	unsigned long flags;
@@ -648,24 +596,8 @@ void mmc_remove_host(struct mmc_host *host)
 	BUG_ON(host->card);
 
 	mmc_power_off(host);
-	mmc_remove_host_sysfs(host);
 }
 
-EXPORT_SYMBOL(mmc_remove_host);
-
-/**
- *	mmc_free_host - free the host structure
- *	@host: mmc host
- *
- *	Free the host once all references to it have been dropped.
- */
-void mmc_free_host(struct mmc_host *host)
-{
-	mmc_free_host_sysfs(host);
-}
-
-EXPORT_SYMBOL(mmc_free_host);
-
 #ifdef CONFIG_PM
 
 /**
@@ -726,4 +658,31 @@ EXPORT_SYMBOL(mmc_resume_host);
 
 #endif
 
+static int __init mmc_init(void)
+{
+	int ret;
+
+	workqueue = create_singlethread_workqueue("kmmcd");
+	if (!workqueue)
+		return -ENOMEM;
+
+	ret = mmc_register_bus();
+	if (ret == 0) {
+		ret = mmc_register_host_class();
+		if (ret)
+			mmc_unregister_bus();
+	}
+	return ret;
+}
+
+static void __exit mmc_exit(void)
+{
+	mmc_unregister_host_class();
+	mmc_unregister_bus();
+	destroy_workqueue(workqueue);
+}
+
+module_init(mmc_init);
+module_exit(mmc_exit);
+
 MODULE_LICENSE("GPL");
diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index 177264d090a..ae006b30dd8 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -18,6 +18,8 @@
 struct mmc_bus_ops {
 	void (*remove)(struct mmc_host *);
 	void (*detect)(struct mmc_host *);
+	int (*sysfs_add)(struct mmc_host *, struct mmc_card *card);
+	void (*sysfs_remove)(struct mmc_host *, struct mmc_card *card);
 	void (*suspend)(struct mmc_host *);
 	void (*resume)(struct mmc_host *);
 };
@@ -54,8 +56,6 @@ void mmc_set_bus_width(struct mmc_host *host, unsigned int width);
 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr);
 void mmc_set_timing(struct mmc_host *host, unsigned int timing);
 
-struct mmc_card *mmc_alloc_card(struct mmc_host *host);
-
 static inline void mmc_delay(unsigned int ms)
 {
 	if (ms < 1000 / HZ) {
@@ -66,5 +66,9 @@ static inline void mmc_delay(unsigned int ms)
 	}
 }
 
+void mmc_rescan(struct work_struct *work);
+void mmc_start_host(struct mmc_host *host);
+void mmc_stop_host(struct mmc_host *host);
+
 #endif
 
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
new file mode 100644
index 00000000000..1433d95c40b
--- /dev/null
+++ b/drivers/mmc/core/host.c
@@ -0,0 +1,156 @@
+/*
+ *  linux/drivers/mmc/core/host.c
+ *
+ *  Copyright (C) 2003 Russell King, All Rights Reserved.
+ *  Copyright (C) 2007 Pierre Ossman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  MMC host class device management
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/idr.h>
+#include <linux/pagemap.h>
+
+#include <linux/mmc/host.h>
+
+#include "core.h"
+#include "host.h"
+
+#define cls_dev_to_mmc_host(d)	container_of(d, struct mmc_host, class_dev)
+
+static void mmc_host_classdev_release(struct device *dev)
+{
+	struct mmc_host *host = cls_dev_to_mmc_host(dev);
+	kfree(host);
+}
+
+static struct class mmc_host_class = {
+	.name		= "mmc_host",
+	.dev_release	= mmc_host_classdev_release,
+};
+
+int mmc_register_host_class(void)
+{
+	return class_register(&mmc_host_class);
+}
+
+void mmc_unregister_host_class(void)
+{
+	class_unregister(&mmc_host_class);
+}
+
+static DEFINE_IDR(mmc_host_idr);
+static DEFINE_SPINLOCK(mmc_host_lock);
+
+/**
+ *	mmc_alloc_host - initialise the per-host structure.
+ *	@extra: sizeof private data structure
+ *	@dev: pointer to host device model structure
+ *
+ *	Initialise the per-host structure.
+ */
+struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
+{
+	struct mmc_host *host;
+
+	host = kmalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
+	if (!host)
+		return NULL;
+
+	memset(host, 0, sizeof(struct mmc_host) + extra);
+
+	host->parent = dev;
+	host->class_dev.parent = dev;
+	host->class_dev.class = &mmc_host_class;
+	device_initialize(&host->class_dev);
+
+	spin_lock_init(&host->lock);
+	init_waitqueue_head(&host->wq);
+	INIT_DELAYED_WORK(&host->detect, mmc_rescan);
+
+	/*
+	 * By default, hosts do not support SGIO or large requests.
+	 * They have to set these according to their abilities.
+	 */
+	host->max_hw_segs = 1;
+	host->max_phys_segs = 1;
+	host->max_seg_size = PAGE_CACHE_SIZE;
+
+	host->max_req_size = PAGE_CACHE_SIZE;
+	host->max_blk_size = 512;
+	host->max_blk_count = PAGE_CACHE_SIZE / 512;
+
+	return host;
+}
+
+EXPORT_SYMBOL(mmc_alloc_host);
+
+/**
+ *	mmc_add_host - initialise host hardware
+ *	@host: mmc host
+ */
+int mmc_add_host(struct mmc_host *host)
+{
+	int err;
+
+	if (!idr_pre_get(&mmc_host_idr, GFP_KERNEL))
+		return -ENOMEM;
+
+	spin_lock(&mmc_host_lock);
+	err = idr_get_new(&mmc_host_idr, host, &host->index);
+	spin_unlock(&mmc_host_lock);
+	if (err)
+		return err;
+
+	snprintf(host->class_dev.bus_id, BUS_ID_SIZE,
+		 "mmc%d", host->index);
+
+	err = device_add(&host->class_dev);
+	if (err)
+		return err;
+
+	mmc_start_host(host);
+
+	return 0;
+}
+
+EXPORT_SYMBOL(mmc_add_host);
+
+/**
+ *	mmc_remove_host - remove host hardware
+ *	@host: mmc host
+ *
+ *	Unregister and remove all cards associated with this host,
+ *	and power down the MMC bus.
+ */
+void mmc_remove_host(struct mmc_host *host)
+{
+	mmc_stop_host(host);
+
+	device_del(&host->class_dev);
+
+	spin_lock(&mmc_host_lock);
+	idr_remove(&mmc_host_idr, host->index);
+	spin_unlock(&mmc_host_lock);
+}
+
+EXPORT_SYMBOL(mmc_remove_host);
+
+/**
+ *	mmc_free_host - free the host structure
+ *	@host: mmc host
+ *
+ *	Free the host once all references to it have been dropped.
+ */
+void mmc_free_host(struct mmc_host *host)
+{
+	put_device(&host->class_dev);
+}
+
+EXPORT_SYMBOL(mmc_free_host);
+
diff --git a/drivers/mmc/core/host.h b/drivers/mmc/core/host.h
new file mode 100644
index 00000000000..c2dc3d2d9f9
--- /dev/null
+++ b/drivers/mmc/core/host.h
@@ -0,0 +1,18 @@
+/*
+ *  linux/drivers/mmc/core/host.h
+ *
+ *  Copyright (C) 2003 Russell King, All Rights Reserved.
+ *  Copyright 2007 Pierre Ossman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef _MMC_CORE_HOST_H
+#define _MMC_CORE_HOST_H
+
+int mmc_register_host_class(void);
+void mmc_unregister_host_class(void);
+
+#endif
+
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 42cc2867ed7..66f85bfa8db 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -18,6 +18,7 @@
 
 #include "core.h"
 #include "sysfs.h"
+#include "bus.h"
 #include "mmc_ops.h"
 
 static const unsigned int tran_exp[] = {
@@ -236,7 +237,7 @@ out:
  * In the case of a resume, "curcard" will contain the card
  * we're trying to reinitialise.
  */
-static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
+static int mmc_init_card(struct mmc_host *host, u32 ocr,
 	struct mmc_card *oldcard)
 {
 	struct mmc_card *card;
@@ -413,8 +414,7 @@ static void mmc_detect(struct mmc_host *host)
 	mmc_release_host(host);
 
 	if (err != MMC_ERR_NONE) {
-		mmc_remove_card(host->card);
-		host->card = NULL;
+		mmc_remove(host);
 
 		mmc_claim_host(host);
 		mmc_detach_bus(host);
@@ -422,6 +