2 * linux/drivers/mmc/core/host.c
4 * Copyright (C) 2003 Russell King, All Rights Reserved.
5 * Copyright (C) 2007 Pierre Ossman
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * MMC host class device management
14 #include <linux/device.h>
15 #include <linux/err.h>
16 #include <linux/idr.h>
17 #include <linux/pagemap.h>
19 #include <linux/mmc/host.h>
24 #define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
26 static void mmc_host_classdev_release(struct device
*dev
)
28 struct mmc_host
*host
= cls_dev_to_mmc_host(dev
);
32 static struct class mmc_host_class
= {
34 .dev_release
= mmc_host_classdev_release
,
37 int mmc_register_host_class(void)
39 return class_register(&mmc_host_class
);
42 void mmc_unregister_host_class(void)
44 class_unregister(&mmc_host_class
);
47 static DEFINE_IDR(mmc_host_idr
);
48 static DEFINE_SPINLOCK(mmc_host_lock
);
51 * mmc_alloc_host - initialise the per-host structure.
52 * @extra: sizeof private data structure
53 * @dev: pointer to host device model structure
55 * Initialise the per-host structure.
57 struct mmc_host
*mmc_alloc_host(int extra
, struct device
*dev
)
59 struct mmc_host
*host
;
61 host
= kmalloc(sizeof(struct mmc_host
) + extra
, GFP_KERNEL
);
65 memset(host
, 0, sizeof(struct mmc_host
) + extra
);
68 host
->class_dev
.parent
= dev
;
69 host
->class_dev
.class = &mmc_host_class
;
70 device_initialize(&host
->class_dev
);
72 spin_lock_init(&host
->lock
);
73 init_waitqueue_head(&host
->wq
);
74 INIT_DELAYED_WORK(&host
->detect
, mmc_rescan
);
77 * By default, hosts do not support SGIO or large requests.
78 * They have to set these according to their abilities.
80 host
->max_hw_segs
= 1;
81 host
->max_phys_segs
= 1;
82 host
->max_seg_size
= PAGE_CACHE_SIZE
;
84 host
->max_req_size
= PAGE_CACHE_SIZE
;
85 host
->max_blk_size
= 512;
86 host
->max_blk_count
= PAGE_CACHE_SIZE
/ 512;
91 EXPORT_SYMBOL(mmc_alloc_host
);
94 * mmc_add_host - initialise host hardware
97 int mmc_add_host(struct mmc_host
*host
)
101 if (!idr_pre_get(&mmc_host_idr
, GFP_KERNEL
))
104 spin_lock(&mmc_host_lock
);
105 err
= idr_get_new(&mmc_host_idr
, host
, &host
->index
);
106 spin_unlock(&mmc_host_lock
);
110 snprintf(host
->class_dev
.bus_id
, BUS_ID_SIZE
,
111 "mmc%d", host
->index
);
113 err
= device_add(&host
->class_dev
);
117 mmc_start_host(host
);
122 EXPORT_SYMBOL(mmc_add_host
);
125 * mmc_remove_host - remove host hardware
128 * Unregister and remove all cards associated with this host,
129 * and power down the MMC bus.
131 void mmc_remove_host(struct mmc_host
*host
)
135 device_del(&host
->class_dev
);
137 spin_lock(&mmc_host_lock
);
138 idr_remove(&mmc_host_idr
, host
->index
);
139 spin_unlock(&mmc_host_lock
);
142 EXPORT_SYMBOL(mmc_remove_host
);
145 * mmc_free_host - free the host structure
148 * Free the host once all references to it have been dropped.
150 void mmc_free_host(struct mmc_host
*host
)
152 put_device(&host
->class_dev
);
155 EXPORT_SYMBOL(mmc_free_host
);