1 /*
2 * linux/drivers/mmc/core/host.c
3 *
4 * Copyright (C) 2003 Russell King, All Rights Reserved.
5 * Copyright (C) 2007-2008 Pierre Ossman
6 *
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.
10 *
11 * MMC host class device management
12 */
13
14 #include <linux/device.h>
15 #include <linux/err.h>
16 #include <linux/idr.h>
17 #include <linux/pagemap.h>
18 #include <linux/leds.h>
19
20 #include <linux/mmc/host.h>
21
22 #include "core.h"
23 #include "host.h"
24
25 #define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
26
mmc_host_classdev_release(struct device * dev)27 static void mmc_host_classdev_release(struct device *dev)
28 {
29 struct mmc_host *host = cls_dev_to_mmc_host(dev);
30 kfree(host);
31 }
32
33 static struct class mmc_host_class = {
34 .name = "mmc_host",
35 .dev_release = mmc_host_classdev_release,
36 };
37
mmc_register_host_class(void)38 int mmc_register_host_class(void)
39 {
40 return class_register(&mmc_host_class);
41 }
42
mmc_unregister_host_class(void)43 void mmc_unregister_host_class(void)
44 {
45 class_unregister(&mmc_host_class);
46 }
47
48 static DEFINE_IDR(mmc_host_idr);
49 static DEFINE_SPINLOCK(mmc_host_lock);
50
51 /**
52 * mmc_alloc_host - initialise the per-host structure.
53 * @extra: sizeof private data structure
54 * @dev: pointer to host device model structure
55 *
56 * Initialise the per-host structure.
57 */
mmc_alloc_host(int extra,struct device * dev)58 struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
59 {
60 int err;
61 struct mmc_host *host;
62
63 if (!idr_pre_get(&mmc_host_idr, GFP_KERNEL))
64 return NULL;
65
66 host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
67 if (!host)
68 return NULL;
69
70 spin_lock(&mmc_host_lock);
71 err = idr_get_new(&mmc_host_idr, host, &host->index);
72 spin_unlock(&mmc_host_lock);
73 if (err)
74 goto free;
75
76 dev_set_name(&host->class_dev, "mmc%d", host->index);
77
78 host->parent = dev;
79 host->class_dev.parent = dev;
80 host->class_dev.class = &mmc_host_class;
81 device_initialize(&host->class_dev);
82
83 spin_lock_init(&host->lock);
84 init_waitqueue_head(&host->wq);
85 INIT_DELAYED_WORK(&host->detect, mmc_rescan);
86
87 /*
88 * By default, hosts do not support SGIO or large requests.
89 * They have to set these according to their abilities.
90 */
91 host->max_hw_segs = 1;
92 host->max_phys_segs = 1;
93 host->max_seg_size = PAGE_CACHE_SIZE;
94
95 host->max_req_size = PAGE_CACHE_SIZE;
96 host->max_blk_size = 512;
97 host->max_blk_count = PAGE_CACHE_SIZE / 512;
98
99 return host;
100
101 free:
102 kfree(host);
103 return NULL;
104 }
105
106 EXPORT_SYMBOL(mmc_alloc_host);
107
108 /**
109 * mmc_add_host - initialise host hardware
110 * @host: mmc host
111 *
112 * Register the host with the driver model. The host must be
113 * prepared to start servicing requests before this function
114 * completes.
115 */
mmc_add_host(struct mmc_host * host)116 int mmc_add_host(struct mmc_host *host)
117 {
118 int err;
119
120 WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) &&
121 !host->ops->enable_sdio_irq);
122
123 led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
124
125 err = device_add(&host->class_dev);
126 if (err)
127 return err;
128
129 #ifdef CONFIG_DEBUG_FS
130 mmc_add_host_debugfs(host);
131 #endif
132
133 mmc_start_host(host);
134
135 return 0;
136 }
137
138 EXPORT_SYMBOL(mmc_add_host);
139
140 /**
141 * mmc_remove_host - remove host hardware
142 * @host: mmc host
143 *
144 * Unregister and remove all cards associated with this host,
145 * and power down the MMC bus. No new requests will be issued
146 * after this function has returned.
147 */
mmc_remove_host(struct mmc_host * host)148 void mmc_remove_host(struct mmc_host *host)
149 {
150 mmc_stop_host(host);
151
152 #ifdef CONFIG_DEBUG_FS
153 mmc_remove_host_debugfs(host);
154 #endif
155
156 device_del(&host->class_dev);
157
158 led_trigger_unregister_simple(host->led);
159 }
160
161 EXPORT_SYMBOL(mmc_remove_host);
162
163 /**
164 * mmc_free_host - free the host structure
165 * @host: mmc host
166 *
167 * Free the host once all references to it have been dropped.
168 */
mmc_free_host(struct mmc_host * host)169 void mmc_free_host(struct mmc_host *host)
170 {
171 spin_lock(&mmc_host_lock);
172 idr_remove(&mmc_host_idr, host->index);
173 spin_unlock(&mmc_host_lock);
174
175 put_device(&host->class_dev);
176 }
177
178 EXPORT_SYMBOL(mmc_free_host);
179
180