[PATCH] driver core: safely unbind drivers for devices not on a bus
[linux-2.6] / drivers / acpi / pci_bind.c
1 /*
2  *  pci_bind.c - ACPI PCI Device Binding ($Revision: 2 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; either version 2 of the License, or (at
12  *  your option) any later version.
13  *
14  *  This program is distributed in the hope that it will be useful, but
15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *  General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License along
20  *  with this program; if not, write to the Free Software Foundation, Inc.,
21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  */
25
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/types.h>
30 #include <linux/proc_fs.h>
31 #include <linux/spinlock.h>
32 #include <linux/pm.h>
33 #include <linux/pci.h>
34 #include <linux/acpi.h>
35 #include <acpi/acpi_bus.h>
36 #include <acpi/acpi_drivers.h>
37
38 #define _COMPONENT              ACPI_PCI_COMPONENT
39 ACPI_MODULE_NAME("pci_bind")
40
41 struct acpi_pci_data {
42         struct acpi_pci_id id;
43         struct pci_bus *bus;
44         struct pci_dev *dev;
45 };
46
47 static void acpi_pci_data_handler(acpi_handle handle, u32 function,
48                                   void *context)
49 {
50         ACPI_FUNCTION_TRACE("acpi_pci_data_handler");
51
52         /* TBD: Anything we need to do here? */
53
54         return_VOID;
55 }
56
57 /**
58  * acpi_get_pci_id
59  * ------------------
60  * This function is used by the ACPI Interpreter (a.k.a. Core Subsystem)
61  * to resolve PCI information for ACPI-PCI devices defined in the namespace.
62  * This typically occurs when resolving PCI operation region information.
63  */
64 acpi_status acpi_get_pci_id(acpi_handle handle, struct acpi_pci_id *id)
65 {
66         int result = 0;
67         acpi_status status = AE_OK;
68         struct acpi_device *device = NULL;
69         struct acpi_pci_data *data = NULL;
70
71         ACPI_FUNCTION_TRACE("acpi_get_pci_id");
72
73         if (!id)
74                 return_ACPI_STATUS(AE_BAD_PARAMETER);
75
76         result = acpi_bus_get_device(handle, &device);
77         if (result) {
78                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
79                                   "Invalid ACPI Bus context for device %s\n",
80                                   acpi_device_bid(device)));
81                 return_ACPI_STATUS(AE_NOT_EXIST);
82         }
83
84         status = acpi_get_data(handle, acpi_pci_data_handler, (void **)&data);
85         if (ACPI_FAILURE(status) || !data) {
86                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
87                                   "Invalid ACPI-PCI context for device %s\n",
88                                   acpi_device_bid(device)));
89                 return_ACPI_STATUS(status);
90         }
91
92         *id = data->id;
93
94         /*
95            id->segment = data->id.segment;
96            id->bus = data->id.bus;
97            id->device = data->id.device;
98            id->function = data->id.function;
99          */
100
101         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
102                           "Device %s has PCI address %02x:%02x:%02x.%02x\n",
103                           acpi_device_bid(device), id->segment, id->bus,
104                           id->device, id->function));
105
106         return_ACPI_STATUS(AE_OK);
107 }
108
109 EXPORT_SYMBOL(acpi_get_pci_id);
110
111 int acpi_pci_bind(struct acpi_device *device)
112 {
113         int result = 0;
114         acpi_status status = AE_OK;
115         struct acpi_pci_data *data = NULL;
116         struct acpi_pci_data *pdata = NULL;
117         char *pathname = NULL;
118         struct acpi_buffer buffer = { 0, NULL };
119         acpi_handle handle = NULL;
120         struct pci_dev *dev;
121         struct pci_bus *bus;
122
123         ACPI_FUNCTION_TRACE("acpi_pci_bind");
124
125         if (!device || !device->parent)
126                 return_VALUE(-EINVAL);
127
128         pathname = kmalloc(ACPI_PATHNAME_MAX, GFP_KERNEL);
129         if (!pathname)
130                 return_VALUE(-ENOMEM);
131         memset(pathname, 0, ACPI_PATHNAME_MAX);
132         buffer.length = ACPI_PATHNAME_MAX;
133         buffer.pointer = pathname;
134
135         data = kmalloc(sizeof(struct acpi_pci_data), GFP_KERNEL);
136         if (!data) {
137                 kfree(pathname);
138                 return_VALUE(-ENOMEM);
139         }
140         memset(data, 0, sizeof(struct acpi_pci_data));
141
142         acpi_get_name(device->handle, ACPI_FULL_PATHNAME, &buffer);
143         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Binding PCI device [%s]...\n",
144                           pathname));
145
146         /* 
147          * Segment & Bus
148          * -------------
149          * These are obtained via the parent device's ACPI-PCI context.
150          */
151         status = acpi_get_data(device->parent->handle, acpi_pci_data_handler,
152                                (void **)&pdata);
153         if (ACPI_FAILURE(status) || !pdata || !pdata->bus) {
154                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
155                                   "Invalid ACPI-PCI context for parent device %s\n",
156                                   acpi_device_bid(device->parent)));
157                 result = -ENODEV;
158                 goto end;
159         }
160         data->id.segment = pdata->id.segment;
161         data->id.bus = pdata->bus->number;
162
163         /*
164          * Device & Function
165          * -----------------
166          * These are simply obtained from the device's _ADR method.  Note
167          * that a value of zero is valid.
168          */
169         data->id.device = device->pnp.bus_address >> 16;
170         data->id.function = device->pnp.bus_address & 0xFFFF;
171
172         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "...to %02x:%02x:%02x.%02x\n",
173                           data->id.segment, data->id.bus, data->id.device,
174                           data->id.function));
175
176         /*
177          * TBD: Support slot devices (e.g. function=0xFFFF).
178          */
179
180         /* 
181          * Locate PCI Device
182          * -----------------
183          * Locate matching device in PCI namespace.  If it doesn't exist
184          * this typically means that the device isn't currently inserted
185          * (e.g. docking station, port replicator, etc.).
186          * We cannot simply search the global pci device list, since
187          * PCI devices are added to the global pci list when the root
188          * bridge start ops are run, which may not have happened yet.
189          */
190         bus = pci_find_bus(data->id.segment, data->id.bus);
191         if (bus) {
192                 list_for_each_entry(dev, &bus->devices, bus_list) {
193                         if (dev->devfn == PCI_DEVFN(data->id.device,
194                                                     data->id.function)) {
195                                 data->dev = dev;
196                                 break;
197                         }
198                 }
199         }
200         if (!data->dev) {
201                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
202                                   "Device %02x:%02x:%02x.%02x not present in PCI namespace\n",
203                                   data->id.segment, data->id.bus,
204                                   data->id.device, data->id.function));
205                 result = -ENODEV;
206                 goto end;
207         }
208         if (!data->dev->bus) {
209                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
210                                   "Device %02x:%02x:%02x.%02x has invalid 'bus' field\n",
211                                   data->id.segment, data->id.bus,
212                                   data->id.device, data->id.function));
213                 result = -ENODEV;
214                 goto end;
215         }
216
217         /*
218          * PCI Bridge?
219          * -----------
220          * If so, set the 'bus' field and install the 'bind' function to 
221          * facilitate callbacks for all of its children.
222          */
223         if (data->dev->subordinate) {
224                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
225                                   "Device %02x:%02x:%02x.%02x is a PCI bridge\n",
226                                   data->id.segment, data->id.bus,
227                                   data->id.device, data->id.function));
228                 data->bus = data->dev->subordinate;
229                 device->ops.bind = acpi_pci_bind;
230                 device->ops.unbind = acpi_pci_unbind;
231         }
232
233         /*
234          * Attach ACPI-PCI Context
235          * -----------------------
236          * Thus binding the ACPI and PCI devices.
237          */
238         status = acpi_attach_data(device->handle, acpi_pci_data_handler, data);
239         if (ACPI_FAILURE(status)) {
240                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
241                                   "Unable to attach ACPI-PCI context to device %s\n",
242                                   acpi_device_bid(device)));
243                 result = -ENODEV;
244                 goto end;
245         }
246
247         /*
248          * PCI Routing Table
249          * -----------------
250          * Evaluate and parse _PRT, if exists.  This code is independent of 
251          * PCI bridges (above) to allow parsing of _PRT objects within the
252          * scope of non-bridge devices.  Note that _PRTs within the scope of
253          * a PCI bridge assume the bridge's subordinate bus number.
254          *
255          * TBD: Can _PRTs exist within the scope of non-bridge PCI devices?
256          */
257         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
258         if (ACPI_SUCCESS(status)) {
259                 if (data->bus)  /* PCI-PCI bridge */
260                         acpi_pci_irq_add_prt(device->handle, data->id.segment,
261                                              data->bus->number);
262                 else            /* non-bridge PCI device */
263                         acpi_pci_irq_add_prt(device->handle, data->id.segment,
264                                              data->id.bus);
265         }
266
267       end:
268         kfree(pathname);
269         if (result)
270                 kfree(data);
271
272         return_VALUE(result);
273 }
274
275 int acpi_pci_unbind(struct acpi_device *device)
276 {
277         int result = 0;
278         acpi_status status = AE_OK;
279         struct acpi_pci_data *data = NULL;
280         char *pathname = NULL;
281         struct acpi_buffer buffer = { 0, NULL };
282
283         ACPI_FUNCTION_TRACE("acpi_pci_unbind");
284
285         if (!device || !device->parent)
286                 return_VALUE(-EINVAL);
287
288         pathname = (char *)kmalloc(ACPI_PATHNAME_MAX, GFP_KERNEL);
289         if (!pathname)
290                 return_VALUE(-ENOMEM);
291         memset(pathname, 0, ACPI_PATHNAME_MAX);
292
293         buffer.length = ACPI_PATHNAME_MAX;
294         buffer.pointer = pathname;
295         acpi_get_name(device->handle, ACPI_FULL_PATHNAME, &buffer);
296         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Unbinding PCI device [%s]...\n",
297                           pathname));
298         kfree(pathname);
299
300         status =
301             acpi_get_data(device->handle, acpi_pci_data_handler,
302                           (void **)&data);
303         if (ACPI_FAILURE(status)) {
304                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
305                                   "Unable to get data from device %s\n",
306                                   acpi_device_bid(device)));
307                 result = -ENODEV;
308                 goto end;
309         }
310
311         status = acpi_detach_data(device->handle, acpi_pci_data_handler);
312         if (ACPI_FAILURE(status)) {
313                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
314                                   "Unable to detach data from device %s\n",
315                                   acpi_device_bid(device)));
316                 result = -ENODEV;
317                 goto end;
318         }
319         if (data->dev->subordinate) {
320                 acpi_pci_irq_del_prt(data->id.segment, data->bus->number);
321         }
322         kfree(data);
323
324       end:
325         return_VALUE(result);
326 }
327
328 int
329 acpi_pci_bind_root(struct acpi_device *device,
330                    struct acpi_pci_id *id, struct pci_bus *bus)
331 {
332         int result = 0;
333         acpi_status status = AE_OK;
334         struct acpi_pci_data *data = NULL;
335         char *pathname = NULL;
336         struct acpi_buffer buffer = { 0, NULL };
337
338         ACPI_FUNCTION_TRACE("acpi_pci_bind_root");
339
340         pathname = (char *)kmalloc(ACPI_PATHNAME_MAX, GFP_KERNEL);
341         if (!pathname)
342                 return_VALUE(-ENOMEM);
343         memset(pathname, 0, ACPI_PATHNAME_MAX);
344
345         buffer.length = ACPI_PATHNAME_MAX;
346         buffer.pointer = pathname;
347
348         if (!device || !id || !bus) {
349                 kfree(pathname);
350                 return_VALUE(-EINVAL);
351         }
352
353         data = kmalloc(sizeof(struct acpi_pci_data), GFP_KERNEL);
354         if (!data) {
355                 kfree(pathname);
356                 return_VALUE(-ENOMEM);
357         }
358         memset(data, 0, sizeof(struct acpi_pci_data));
359
360         data->id = *id;
361         data->bus = bus;
362         device->ops.bind = acpi_pci_bind;
363         device->ops.unbind = acpi_pci_unbind;
364
365         acpi_get_name(device->handle, ACPI_FULL_PATHNAME, &buffer);
366
367         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Binding PCI root bridge [%s] to "
368                           "%02x:%02x\n", pathname, id->segment, id->bus));
369
370         status = acpi_attach_data(device->handle, acpi_pci_data_handler, data);
371         if (ACPI_FAILURE(status)) {
372                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
373                                   "Unable to attach ACPI-PCI context to device %s\n",
374                                   pathname));
375                 result = -ENODEV;
376                 goto end;
377         }
378
379       end:
380         kfree(pathname);
381         if (result != 0)
382                 kfree(data);
383
384         return_VALUE(result);
385 }