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 #include <linux/slab.h> 20 21 #include <linux/mmc/host.h> 22 23 #include "core.h" 24 #include "host.h" 25 26 #define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev) 27 28 static void mmc_host_classdev_release(struct device *dev) 29 { 30 struct mmc_host *host = cls_dev_to_mmc_host(dev); 31 kfree(host); 32 } 33 34 static struct class mmc_host_class = { 35 .name = "mmc_host", 36 .dev_release = mmc_host_classdev_release, 37 }; 38 39 int mmc_register_host_class(void) 40 { 41 return class_register(&mmc_host_class); 42 } 43 44 void mmc_unregister_host_class(void) 45 { 46 class_unregister(&mmc_host_class); 47 } 48 49 static DEFINE_IDR(mmc_host_idr); 50 static DEFINE_SPINLOCK(mmc_host_lock); 51 52 /** 53 * mmc_alloc_host - initialise the per-host structure. 54 * @extra: sizeof private data structure 55 * @dev: pointer to host device model structure 56 * 57 * Initialise the per-host structure. 58 */ 59 struct mmc_host *mmc_alloc_host(int extra, struct device *dev) 60 { 61 int err; 62 struct mmc_host *host; 63 64 if (!idr_pre_get(&mmc_host_idr, GFP_KERNEL)) 65 return NULL; 66 67 host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL); 68 if (!host) 69 return NULL; 70 71 spin_lock(&mmc_host_lock); 72 err = idr_get_new(&mmc_host_idr, host, &host->index); 73 spin_unlock(&mmc_host_lock); 74 if (err) 75 goto free; 76 77 dev_set_name(&host->class_dev, "mmc%d", host->index); 78 79 host->parent = dev; 80 host->class_dev.parent = dev; 81 host->class_dev.class = &mmc_host_class; 82 device_initialize(&host->class_dev); 83 84 spin_lock_init(&host->lock); 85 init_waitqueue_head(&host->wq); 86 INIT_DELAYED_WORK(&host->detect, mmc_rescan); 87 INIT_DELAYED_WORK_DEFERRABLE(&host->disable, mmc_host_deeper_disable); 88 89 /* 90 * By default, hosts do not support SGIO or large requests. 91 * They have to set these according to their abilities. 92 */ 93 host->max_hw_segs = 1; 94 host->max_phys_segs = 1; 95 host->max_seg_size = PAGE_CACHE_SIZE; 96 97 host->max_req_size = PAGE_CACHE_SIZE; 98 host->max_blk_size = 512; 99 host->max_blk_count = PAGE_CACHE_SIZE / 512; 100 101 return host; 102 103 free: 104 kfree(host); 105 return NULL; 106 } 107 108 EXPORT_SYMBOL(mmc_alloc_host); 109 110 /** 111 * mmc_add_host - initialise host hardware 112 * @host: mmc host 113 * 114 * Register the host with the driver model. The host must be 115 * prepared to start servicing requests before this function 116 * completes. 117 */ 118 int mmc_add_host(struct mmc_host *host) 119 { 120 int err; 121 122 WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) && 123 !host->ops->enable_sdio_irq); 124 125 led_trigger_register_simple(dev_name(&host->class_dev), &host->led); 126 127 err = device_add(&host->class_dev); 128 if (err) 129 return err; 130 131 #ifdef CONFIG_DEBUG_FS 132 mmc_add_host_debugfs(host); 133 #endif 134 135 mmc_start_host(host); 136 137 return 0; 138 } 139 140 EXPORT_SYMBOL(mmc_add_host); 141 142 /** 143 * mmc_remove_host - remove host hardware 144 * @host: mmc host 145 * 146 * Unregister and remove all cards associated with this host, 147 * and power down the MMC bus. No new requests will be issued 148 * after this function has returned. 149 */ 150 void mmc_remove_host(struct mmc_host *host) 151 { 152 mmc_stop_host(host); 153 154 #ifdef CONFIG_DEBUG_FS 155 mmc_remove_host_debugfs(host); 156 #endif 157 158 device_del(&host->class_dev); 159 160 led_trigger_unregister_simple(host->led); 161 } 162 163 EXPORT_SYMBOL(mmc_remove_host); 164 165 /** 166 * mmc_free_host - free the host structure 167 * @host: mmc host 168 * 169 * Free the host once all references to it have been dropped. 170 */ 171 void mmc_free_host(struct mmc_host *host) 172 { 173 spin_lock(&mmc_host_lock); 174 idr_remove(&mmc_host_idr, host->index); 175 spin_unlock(&mmc_host_lock); 176 177 put_device(&host->class_dev); 178 } 179 180 EXPORT_SYMBOL(mmc_free_host); 181 182