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 #include <linux/suspend.h> 21 22 #include <linux/mmc/host.h> 23 24 #include "core.h" 25 #include "host.h" 26 27 #define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev) 28 29 static void mmc_host_classdev_release(struct device *dev) 30 { 31 struct mmc_host *host = cls_dev_to_mmc_host(dev); 32 kfree(host); 33 } 34 35 static struct class mmc_host_class = { 36 .name = "mmc_host", 37 .dev_release = mmc_host_classdev_release, 38 }; 39 40 int mmc_register_host_class(void) 41 { 42 return class_register(&mmc_host_class); 43 } 44 45 void mmc_unregister_host_class(void) 46 { 47 class_unregister(&mmc_host_class); 48 } 49 50 static DEFINE_IDR(mmc_host_idr); 51 static DEFINE_SPINLOCK(mmc_host_lock); 52 53 /** 54 * mmc_alloc_host - initialise the per-host structure. 55 * @extra: sizeof private data structure 56 * @dev: pointer to host device model structure 57 * 58 * Initialise the per-host structure. 59 */ 60 struct mmc_host *mmc_alloc_host(int extra, struct device *dev) 61 { 62 int err; 63 struct mmc_host *host; 64 65 if (!idr_pre_get(&mmc_host_idr, GFP_KERNEL)) 66 return NULL; 67 68 host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL); 69 if (!host) 70 return NULL; 71 72 spin_lock(&mmc_host_lock); 73 err = idr_get_new(&mmc_host_idr, host, &host->index); 74 spin_unlock(&mmc_host_lock); 75 if (err) 76 goto free; 77 78 dev_set_name(&host->class_dev, "mmc%d", host->index); 79 80 host->parent = dev; 81 host->class_dev.parent = dev; 82 host->class_dev.class = &mmc_host_class; 83 device_initialize(&host->class_dev); 84 85 spin_lock_init(&host->lock); 86 init_waitqueue_head(&host->wq); 87 INIT_DELAYED_WORK(&host->detect, mmc_rescan); 88 INIT_DELAYED_WORK_DEFERRABLE(&host->disable, mmc_host_deeper_disable); 89 host->pm_notify.notifier_call = mmc_pm_notify; 90 91 /* 92 * By default, hosts do not support SGIO or large requests. 93 * They have to set these according to their abilities. 94 */ 95 host->max_hw_segs = 1; 96 host->max_phys_segs = 1; 97 host->max_seg_size = PAGE_CACHE_SIZE; 98 99 host->max_req_size = PAGE_CACHE_SIZE; 100 host->max_blk_size = 512; 101 host->max_blk_count = PAGE_CACHE_SIZE / 512; 102 103 return host; 104 105 free: 106 kfree(host); 107 return NULL; 108 } 109 110 EXPORT_SYMBOL(mmc_alloc_host); 111 112 /** 113 * mmc_add_host - initialise host hardware 114 * @host: mmc host 115 * 116 * Register the host with the driver model. The host must be 117 * prepared to start servicing requests before this function 118 * completes. 119 */ 120 int mmc_add_host(struct mmc_host *host) 121 { 122 int err; 123 124 WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) && 125 !host->ops->enable_sdio_irq); 126 127 led_trigger_register_simple(dev_name(&host->class_dev), &host->led); 128 129 err = device_add(&host->class_dev); 130 if (err) 131 return err; 132 133 #ifdef CONFIG_DEBUG_FS 134 mmc_add_host_debugfs(host); 135 #endif 136 137 mmc_start_host(host); 138 register_pm_notifier(&host->pm_notify); 139 140 return 0; 141 } 142 143 EXPORT_SYMBOL(mmc_add_host); 144 145 /** 146 * mmc_remove_host - remove host hardware 147 * @host: mmc host 148 * 149 * Unregister and remove all cards associated with this host, 150 * and power down the MMC bus. No new requests will be issued 151 * after this function has returned. 152 */ 153 void mmc_remove_host(struct mmc_host *host) 154 { 155 unregister_pm_notifier(&host->pm_notify); 156 mmc_stop_host(host); 157 158 #ifdef CONFIG_DEBUG_FS 159 mmc_remove_host_debugfs(host); 160 #endif 161 162 device_del(&host->class_dev); 163 164 led_trigger_unregister_simple(host->led); 165 } 166 167 EXPORT_SYMBOL(mmc_remove_host); 168 169 /** 170 * mmc_free_host - free the host structure 171 * @host: mmc host 172 * 173 * Free the host once all references to it have been dropped. 174 */ 175 void mmc_free_host(struct mmc_host *host) 176 { 177 spin_lock(&mmc_host_lock); 178 idr_remove(&mmc_host_idr, host->index); 179 spin_unlock(&mmc_host_lock); 180 181 put_device(&host->class_dev); 182 } 183 184 EXPORT_SYMBOL(mmc_free_host); 185 186