1/* 2 * Bus for UWB Multi-interface Controller capabilities. 3 * 4 * Copyright (C) 2007 Cambridge Silicon Radio Ltd. 5 * 6 * This file is released under the GNU GPL v2. 7 */ 8#include <linux/kernel.h> 9#include <linux/sysfs.h> 10#include <linux/workqueue.h> 11#include <linux/uwb/umc.h> 12#include <linux/pci.h> 13 14static int umc_bus_pre_reset_helper(struct device *dev, void *data) 15{ 16 int ret = 0; 17 18 if (dev->driver) { 19 struct umc_dev *umc = to_umc_dev(dev); 20 struct umc_driver *umc_drv = to_umc_driver(dev->driver); 21 22 if (umc_drv->pre_reset) 23 ret = umc_drv->pre_reset(umc); 24 else 25 device_release_driver(dev); 26 } 27 return ret; 28} 29 30static int umc_bus_post_reset_helper(struct device *dev, void *data) 31{ 32 int ret = 0; 33 34 if (dev->driver) { 35 struct umc_dev *umc = to_umc_dev(dev); 36 struct umc_driver *umc_drv = to_umc_driver(dev->driver); 37 38 if (umc_drv->post_reset) 39 ret = umc_drv->post_reset(umc); 40 } else 41 ret = device_attach(dev); 42 43 return ret; 44} 45 46/** 47 * umc_controller_reset - reset the whole UMC controller 48 * @umc: the UMC device for the radio controller. 49 * 50 * Drivers or all capabilities of the controller will have their 51 * pre_reset methods called or be unbound from their device. Then all 52 * post_reset methods will be called or the drivers will be rebound. 53 * 54 * Radio controllers must provide pre_reset and post_reset methods and 55 * reset the hardware in their start method. 56 * 57 * If this is called while a probe() or remove() is in progress it 58 * will return -EAGAIN and not perform the reset. 59 */ 60int umc_controller_reset(struct umc_dev *umc) 61{ 62 struct device *parent = umc->dev.parent; 63 int ret = 0; 64 65 if (device_trylock(parent)) 66 return -EAGAIN; 67 ret = device_for_each_child(parent, parent, umc_bus_pre_reset_helper); 68 if (ret >= 0) 69 ret = device_for_each_child(parent, parent, umc_bus_post_reset_helper); 70 device_unlock(parent); 71 72 return ret; 73} 74EXPORT_SYMBOL_GPL(umc_controller_reset); 75 76/** 77 * umc_match_pci_id - match a UMC driver to a UMC device's parent PCI device. 78 * @umc_drv: umc driver with match_data pointing to a zero-terminated 79 * table of pci_device_id's. 80 * @umc: umc device whose parent is to be matched. 81 */ 82int umc_match_pci_id(struct umc_driver *umc_drv, struct umc_dev *umc) 83{ 84 const struct pci_device_id *id_table = umc_drv->match_data; 85 struct pci_dev *pci; 86 87 if (umc->dev.parent->bus != &pci_bus_type) 88 return 0; 89 90 pci = to_pci_dev(umc->dev.parent); 91 return pci_match_id(id_table, pci) != NULL; 92} 93EXPORT_SYMBOL_GPL(umc_match_pci_id); 94 95static int umc_bus_rescan_helper(struct device *dev, void *data) 96{ 97 int ret = 0; 98 99 if (!dev->driver) 100 ret = device_attach(dev); 101 102 return ret; 103} 104 105static void umc_bus_rescan(struct device *parent) 106{ 107 int err; 108 109 /* 110 * We can't use bus_rescan_devices() here as it deadlocks when 111 * it tries to retake the dev->parent semaphore. 112 */ 113 err = device_for_each_child(parent, NULL, umc_bus_rescan_helper); 114 if (err < 0) 115 printk(KERN_WARNING "%s: rescan of bus failed: %d\n", 116 KBUILD_MODNAME, err); 117} 118 119static int umc_bus_match(struct device *dev, struct device_driver *drv) 120{ 121 struct umc_dev *umc = to_umc_dev(dev); 122 struct umc_driver *umc_driver = to_umc_driver(drv); 123 124 if (umc->cap_id == umc_driver->cap_id) { 125 if (umc_driver->match) 126 return umc_driver->match(umc_driver, umc); 127 else 128 return 1; 129 } 130 return 0; 131} 132 133static int umc_device_probe(struct device *dev) 134{ 135 struct umc_dev *umc; 136 struct umc_driver *umc_driver; 137 int err; 138 139 umc_driver = to_umc_driver(dev->driver); 140 umc = to_umc_dev(dev); 141 142 get_device(dev); 143 err = umc_driver->probe(umc); 144 if (err) 145 put_device(dev); 146 else 147 umc_bus_rescan(dev->parent); 148 149 return err; 150} 151 152static int umc_device_remove(struct device *dev) 153{ 154 struct umc_dev *umc; 155 struct umc_driver *umc_driver; 156 157 umc_driver = to_umc_driver(dev->driver); 158 umc = to_umc_dev(dev); 159 160 umc_driver->remove(umc); 161 put_device(dev); 162 return 0; 163} 164 165static int umc_device_suspend(struct device *dev, pm_message_t state) 166{ 167 struct umc_dev *umc; 168 struct umc_driver *umc_driver; 169 int err = 0; 170 171 umc = to_umc_dev(dev); 172 173 if (dev->driver) { 174 umc_driver = to_umc_driver(dev->driver); 175 if (umc_driver->suspend) 176 err = umc_driver->suspend(umc, state); 177 } 178 return err; 179} 180 181static int umc_device_resume(struct device *dev) 182{ 183 struct umc_dev *umc; 184 struct umc_driver *umc_driver; 185 int err = 0; 186 187 umc = to_umc_dev(dev); 188 189 if (dev->driver) { 190 umc_driver = to_umc_driver(dev->driver); 191 if (umc_driver->resume) 192 err = umc_driver->resume(umc); 193 } 194 return err; 195} 196 197static ssize_t capability_id_show(struct device *dev, struct device_attribute *attr, char *buf) 198{ 199 struct umc_dev *umc = to_umc_dev(dev); 200 201 return sprintf(buf, "0x%02x\n", umc->cap_id); 202} 203 204static ssize_t version_show(struct device *dev, struct device_attribute *attr, char *buf) 205{ 206 struct umc_dev *umc = to_umc_dev(dev); 207 208 return sprintf(buf, "0x%04x\n", umc->version); 209} 210 211static struct device_attribute umc_dev_attrs[] = { 212 __ATTR_RO(capability_id), 213 __ATTR_RO(version), 214 __ATTR_NULL, 215}; 216 217struct bus_type umc_bus_type = { 218 .name = "umc", 219 .match = umc_bus_match, 220 .probe = umc_device_probe, 221 .remove = umc_device_remove, 222 .suspend = umc_device_suspend, 223 .resume = umc_device_resume, 224 .dev_attrs = umc_dev_attrs, 225}; 226EXPORT_SYMBOL_GPL(umc_bus_type); 227 228static int __init umc_bus_init(void) 229{ 230 return bus_register(&umc_bus_type); 231} 232module_init(umc_bus_init); 233 234static void __exit umc_bus_exit(void) 235{ 236 bus_unregister(&umc_bus_type); 237} 238module_exit(umc_bus_exit); 239 240MODULE_DESCRIPTION("UWB Multi-interface Controller capability bus"); 241MODULE_AUTHOR("Cambridge Silicon Radio Ltd."); 242MODULE_LICENSE("GPL"); 243