x86/amd-iommu: Add per IOMMU reference counting
[linux/fpc-iii.git] / drivers / uwb / umc-bus.c
blobcdd6c8efc9f8ccadef82a989f2269ffd17f01151
1 /*
2 * Bus for UWB Multi-interface Controller capabilities.
4 * Copyright (C) 2007 Cambridge Silicon Radio Ltd.
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>
14 static int umc_bus_pre_reset_helper(struct device *dev, void *data)
16 int ret = 0;
18 if (dev->driver) {
19 struct umc_dev *umc = to_umc_dev(dev);
20 struct umc_driver *umc_drv = to_umc_driver(dev->driver);
22 if (umc_drv->pre_reset)
23 ret = umc_drv->pre_reset(umc);
24 else
25 device_release_driver(dev);
27 return ret;
30 static int umc_bus_post_reset_helper(struct device *dev, void *data)
32 int ret = 0;
34 if (dev->driver) {
35 struct umc_dev *umc = to_umc_dev(dev);
36 struct umc_driver *umc_drv = to_umc_driver(dev->driver);
38 if (umc_drv->post_reset)
39 ret = umc_drv->post_reset(umc);
40 } else
41 ret = device_attach(dev);
43 return ret;
46 /**
47 * umc_controller_reset - reset the whole UMC controller
48 * @umc: the UMC device for the radio controller.
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.
54 * Radio controllers must provide pre_reset and post_reset methods and
55 * reset the hardware in their start method.
57 * If this is called while a probe() or remove() is in progress it
58 * will return -EAGAIN and not perform the reset.
60 int umc_controller_reset(struct umc_dev *umc)
62 struct device *parent = umc->dev.parent;
63 int ret = 0;
65 if(down_trylock(&parent->sem))
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 up(&parent->sem);
72 return ret;
74 EXPORT_SYMBOL_GPL(umc_controller_reset);
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.
82 int umc_match_pci_id(struct umc_driver *umc_drv, struct umc_dev *umc)
84 const struct pci_device_id *id_table = umc_drv->match_data;
85 struct pci_dev *pci;
87 if (umc->dev.parent->bus != &pci_bus_type)
88 return 0;
90 pci = to_pci_dev(umc->dev.parent);
91 return pci_match_id(id_table, pci) != NULL;
93 EXPORT_SYMBOL_GPL(umc_match_pci_id);
95 static int umc_bus_rescan_helper(struct device *dev, void *data)
97 int ret = 0;
99 if (!dev->driver)
100 ret = device_attach(dev);
102 return ret;
105 static void umc_bus_rescan(struct device *parent)
107 int err;
110 * We can't use bus_rescan_devices() here as it deadlocks when
111 * it tries to retake the dev->parent semaphore.
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);
119 static int umc_bus_match(struct device *dev, struct device_driver *drv)
121 struct umc_dev *umc = to_umc_dev(dev);
122 struct umc_driver *umc_driver = to_umc_driver(drv);
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;
130 return 0;
133 static int umc_device_probe(struct device *dev)
135 struct umc_dev *umc;
136 struct umc_driver *umc_driver;
137 int err;
139 umc_driver = to_umc_driver(dev->driver);
140 umc = to_umc_dev(dev);
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);
149 return err;
152 static int umc_device_remove(struct device *dev)
154 struct umc_dev *umc;
155 struct umc_driver *umc_driver;
157 umc_driver = to_umc_driver(dev->driver);
158 umc = to_umc_dev(dev);
160 umc_driver->remove(umc);
161 put_device(dev);
162 return 0;
165 static int umc_device_suspend(struct device *dev, pm_message_t state)
167 struct umc_dev *umc;
168 struct umc_driver *umc_driver;
169 int err = 0;
171 umc = to_umc_dev(dev);
173 if (dev->driver) {
174 umc_driver = to_umc_driver(dev->driver);
175 if (umc_driver->suspend)
176 err = umc_driver->suspend(umc, state);
178 return err;
181 static int umc_device_resume(struct device *dev)
183 struct umc_dev *umc;
184 struct umc_driver *umc_driver;
185 int err = 0;
187 umc = to_umc_dev(dev);
189 if (dev->driver) {
190 umc_driver = to_umc_driver(dev->driver);
191 if (umc_driver->resume)
192 err = umc_driver->resume(umc);
194 return err;
197 static ssize_t capability_id_show(struct device *dev, struct device_attribute *attr, char *buf)
199 struct umc_dev *umc = to_umc_dev(dev);
201 return sprintf(buf, "0x%02x\n", umc->cap_id);
204 static ssize_t version_show(struct device *dev, struct device_attribute *attr, char *buf)
206 struct umc_dev *umc = to_umc_dev(dev);
208 return sprintf(buf, "0x%04x\n", umc->version);
211 static struct device_attribute umc_dev_attrs[] = {
212 __ATTR_RO(capability_id),
213 __ATTR_RO(version),
214 __ATTR_NULL,
217 struct 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,
226 EXPORT_SYMBOL_GPL(umc_bus_type);
228 static int __init umc_bus_init(void)
230 return bus_register(&umc_bus_type);
232 module_init(umc_bus_init);
234 static void __exit umc_bus_exit(void)
236 bus_unregister(&umc_bus_type);
238 module_exit(umc_bus_exit);
240 MODULE_DESCRIPTION("UWB Multi-interface Controller capability bus");
241 MODULE_AUTHOR("Cambridge Silicon Radio Ltd.");
242 MODULE_LICENSE("GPL");