mmc: refactor host class handling

Move basic host class device handling to its own file for clarity.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

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);
+