ACPI: fix 80 char overflow
[linux-2.6.git] / drivers / acpi / acpi_ipmi.c
1 /*
2  *  acpi_ipmi.c - ACPI IPMI opregion
3  *
4  *  Copyright (C) 2010 Intel Corporation
5  *  Copyright (C) 2010 Zhao Yakui <yakui.zhao@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/delay.h>
31 #include <linux/proc_fs.h>
32 #include <linux/seq_file.h>
33 #include <linux/interrupt.h>
34 #include <linux/list.h>
35 #include <linux/spinlock.h>
36 #include <linux/io.h>
37 #include <acpi/acpi_bus.h>
38 #include <acpi/acpi_drivers.h>
39 #include <linux/ipmi.h>
40 #include <linux/device.h>
41 #include <linux/pnp.h>
42
43 MODULE_AUTHOR("Zhao Yakui");
44 MODULE_DESCRIPTION("ACPI IPMI Opregion driver");
45 MODULE_LICENSE("GPL");
46
47 #define IPMI_FLAGS_HANDLER_INSTALL      0
48
49 #define ACPI_IPMI_OK                    0
50 #define ACPI_IPMI_TIMEOUT               0x10
51 #define ACPI_IPMI_UNKNOWN               0x07
52 /* the IPMI timeout is 5s */
53 #define IPMI_TIMEOUT                    (5 * HZ)
54
55 struct acpi_ipmi_device {
56         /* the device list attached to driver_data.ipmi_devices */
57         struct list_head head;
58         /* the IPMI request message list */
59         struct list_head tx_msg_list;
60         struct mutex    tx_msg_lock;
61         acpi_handle handle;
62         struct pnp_dev *pnp_dev;
63         ipmi_user_t     user_interface;
64         int ipmi_ifnum; /* IPMI interface number */
65         long curr_msgid;
66         unsigned long flags;
67         struct ipmi_smi_info smi_data;
68 };
69
70 struct ipmi_driver_data {
71         struct list_head        ipmi_devices;
72         struct ipmi_smi_watcher bmc_events;
73         struct ipmi_user_hndl   ipmi_hndlrs;
74         struct mutex            ipmi_lock;
75 };
76
77 struct acpi_ipmi_msg {
78         struct list_head head;
79         /*
80          * General speaking the addr type should be SI_ADDR_TYPE. And
81          * the addr channel should be BMC.
82          * In fact it can also be IPMB type. But we will have to
83          * parse it from the Netfn command buffer. It is so complex
84          * that it is skipped.
85          */
86         struct ipmi_addr addr;
87         long tx_msgid;
88         /* it is used to track whether the IPMI message is finished */
89         struct completion tx_complete;
90         struct kernel_ipmi_msg tx_message;
91         int     msg_done;
92         /* tx data . And copy it from ACPI object buffer */
93         u8      tx_data[64];
94         int     tx_len;
95         u8      rx_data[64];
96         int     rx_len;
97         struct acpi_ipmi_device *device;
98 };
99
100 /* IPMI request/response buffer per ACPI 4.0, sec 5.5.2.4.3.2 */
101 struct acpi_ipmi_buffer {
102         u8 status;
103         u8 length;
104         u8 data[64];
105 };
106
107 static void ipmi_register_bmc(int iface, struct device *dev);
108 static void ipmi_bmc_gone(int iface);
109 static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
110 static void acpi_add_ipmi_device(struct acpi_ipmi_device *ipmi_device);
111 static void acpi_remove_ipmi_device(struct acpi_ipmi_device *ipmi_device);
112
113 static struct ipmi_driver_data driver_data = {
114         .ipmi_devices = LIST_HEAD_INIT(driver_data.ipmi_devices),
115         .bmc_events = {
116                 .owner = THIS_MODULE,
117                 .new_smi = ipmi_register_bmc,
118                 .smi_gone = ipmi_bmc_gone,
119         },
120         .ipmi_hndlrs = {
121                 .ipmi_recv_hndl = ipmi_msg_handler,
122         },
123 };
124
125 static struct acpi_ipmi_msg *acpi_alloc_ipmi_msg(struct acpi_ipmi_device *ipmi)
126 {
127         struct acpi_ipmi_msg *ipmi_msg;
128         struct pnp_dev *pnp_dev = ipmi->pnp_dev;
129
130         ipmi_msg = kzalloc(sizeof(struct acpi_ipmi_msg), GFP_KERNEL);
131         if (!ipmi_msg)  {
132                 dev_warn(&pnp_dev->dev, "Can't allocate memory for ipmi_msg\n");
133                 return NULL;
134         }
135         init_completion(&ipmi_msg->tx_complete);
136         INIT_LIST_HEAD(&ipmi_msg->head);
137         ipmi_msg->device = ipmi;
138         return ipmi_msg;
139 }
140
141 #define         IPMI_OP_RGN_NETFN(offset)       ((offset >> 8) & 0xff)
142 #define         IPMI_OP_RGN_CMD(offset)         (offset & 0xff)
143 static void acpi_format_ipmi_msg(struct acpi_ipmi_msg *tx_msg,
144                                 acpi_physical_address address,
145                                 acpi_integer *value)
146 {
147         struct kernel_ipmi_msg *msg;
148         struct acpi_ipmi_buffer *buffer;
149         struct acpi_ipmi_device *device;
150
151         msg = &tx_msg->tx_message;
152         /*
153          * IPMI network function and command are encoded in the address
154          * within the IPMI OpRegion; see ACPI 4.0, sec 5.5.2.4.3.
155          */
156         msg->netfn = IPMI_OP_RGN_NETFN(address);
157         msg->cmd = IPMI_OP_RGN_CMD(address);
158         msg->data = tx_msg->tx_data;
159         /*
160          * value is the parameter passed by the IPMI opregion space handler.
161          * It points to the IPMI request message buffer
162          */
163         buffer = (struct acpi_ipmi_buffer *)value;
164         /* copy the tx message data */
165         msg->data_len = buffer->length;
166         memcpy(tx_msg->tx_data, buffer->data, msg->data_len);
167         /*
168          * now the default type is SYSTEM_INTERFACE and channel type is BMC.
169          * If the netfn is APP_REQUEST and the cmd is SEND_MESSAGE,
170          * the addr type should be changed to IPMB. Then we will have to parse
171          * the IPMI request message buffer to get the IPMB address.
172          * If so, please fix me.
173          */
174         tx_msg->addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
175         tx_msg->addr.channel = IPMI_BMC_CHANNEL;
176         tx_msg->addr.data[0] = 0;
177
178         /* Get the msgid */
179         device = tx_msg->device;
180         mutex_lock(&device->tx_msg_lock);
181         device->curr_msgid++;
182         tx_msg->tx_msgid = device->curr_msgid;
183         mutex_unlock(&device->tx_msg_lock);
184 }
185
186 static void acpi_format_ipmi_response(struct acpi_ipmi_msg *msg,
187                 acpi_integer *value, int rem_time)
188 {
189         struct acpi_ipmi_buffer *buffer;
190
191         /*
192          * value is also used as output parameter. It represents the response
193          * IPMI message returned by IPMI command.
194          */
195         buffer = (struct acpi_ipmi_buffer *)value;
196         if (!rem_time && !msg->msg_done) {
197                 buffer->status = ACPI_IPMI_TIMEOUT;
198                 return;
199         }
200         /*
201          * If the flag of msg_done is not set or the recv length is zero, it
202          * means that the IPMI command is not executed correctly.
203          * The status code will be ACPI_IPMI_UNKNOWN.
204          */
205         if (!msg->msg_done || !msg->rx_len) {
206                 buffer->status = ACPI_IPMI_UNKNOWN;
207                 return;
208         }
209         /*
210          * If the IPMI response message is obtained correctly, the status code
211          * will be ACPI_IPMI_OK
212          */
213         buffer->status = ACPI_IPMI_OK;
214         buffer->length = msg->rx_len;
215         memcpy(buffer->data, msg->rx_data, msg->rx_len);
216 }
217
218 static void ipmi_flush_tx_msg(struct acpi_ipmi_device *ipmi)
219 {
220         struct acpi_ipmi_msg *tx_msg, *temp;
221         int count = HZ / 10;
222         struct pnp_dev *pnp_dev = ipmi->pnp_dev;
223
224         list_for_each_entry_safe(tx_msg, temp, &ipmi->tx_msg_list, head) {
225                 /* wake up the sleep thread on the Tx msg */
226                 complete(&tx_msg->tx_complete);
227         }
228
229         /* wait for about 100ms to flush the tx message list */
230         while (count--) {
231                 if (list_empty(&ipmi->tx_msg_list))
232                         break;
233                 schedule_timeout(1);
234         }
235         if (!list_empty(&ipmi->tx_msg_list))
236                 dev_warn(&pnp_dev->dev, "tx msg list is not NULL\n");
237 }
238
239 static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
240 {
241         struct acpi_ipmi_device *ipmi_device = user_msg_data;
242         int msg_found = 0;
243         struct acpi_ipmi_msg *tx_msg;
244         struct pnp_dev *pnp_dev = ipmi_device->pnp_dev;
245
246         if (msg->user != ipmi_device->user_interface) {
247                 dev_warn(&pnp_dev->dev, "Unexpected response is returned. "
248                         "returned user %p, expected user %p\n",
249                         msg->user, ipmi_device->user_interface);
250                 ipmi_free_recv_msg(msg);
251                 return;
252         }
253         mutex_lock(&ipmi_device->tx_msg_lock);
254         list_for_each_entry(tx_msg, &ipmi_device->tx_msg_list, head) {
255                 if (msg->msgid == tx_msg->tx_msgid) {
256                         msg_found = 1;
257                         break;
258                 }
259         }
260
261         mutex_unlock(&ipmi_device->tx_msg_lock);
262         if (!msg_found) {
263                 dev_warn(&pnp_dev->dev, "Unexpected response (msg id %ld) is "
264                         "returned.\n", msg->msgid);
265                 ipmi_free_recv_msg(msg);
266                 return;
267         }
268
269         if (msg->msg.data_len) {
270                 /* copy the response data to Rx_data buffer */
271                 memcpy(tx_msg->rx_data, msg->msg_data, msg->msg.data_len);
272                 tx_msg->rx_len = msg->msg.data_len;
273                 tx_msg->msg_done = 1;
274         }
275         complete(&tx_msg->tx_complete);
276         ipmi_free_recv_msg(msg);
277 };
278
279 static void ipmi_register_bmc(int iface, struct device *dev)
280 {
281         struct acpi_ipmi_device *ipmi_device, *temp;
282         struct pnp_dev *pnp_dev;
283         ipmi_user_t             user;
284         int err;
285         struct ipmi_smi_info smi_data;
286         acpi_handle handle;
287
288         err = ipmi_get_smi_info(iface, &smi_data);
289
290         if (err)
291                 return;
292
293         if (smi_data.addr_src != SI_ACPI) {
294                 put_device(smi_data.dev);
295                 return;
296         }
297
298         handle = smi_data.addr_info.acpi_info.acpi_handle;
299
300         mutex_lock(&driver_data.ipmi_lock);
301         list_for_each_entry(temp, &driver_data.ipmi_devices, head) {
302                 /*
303                  * if the corresponding ACPI handle is already added
304                  * to the device list, don't add it again.
305                  */
306                 if (temp->handle == handle)
307                         goto out;
308         }
309
310         ipmi_device = kzalloc(sizeof(*ipmi_device), GFP_KERNEL);
311
312         if (!ipmi_device)
313                 goto out;
314
315         pnp_dev = to_pnp_dev(smi_data.dev);
316         ipmi_device->handle = handle;
317         ipmi_device->pnp_dev = pnp_dev;
318
319         err = ipmi_create_user(iface, &driver_data.ipmi_hndlrs,
320                                         ipmi_device, &user);
321         if (err) {
322                 dev_warn(&pnp_dev->dev, "Can't create IPMI user interface\n");
323                 kfree(ipmi_device);
324                 goto out;
325         }
326         acpi_add_ipmi_device(ipmi_device);
327         ipmi_device->user_interface = user;
328         ipmi_device->ipmi_ifnum = iface;
329         mutex_unlock(&driver_data.ipmi_lock);
330         memcpy(&ipmi_device->smi_data, &smi_data, sizeof(struct ipmi_smi_info));
331         return;
332
333 out:
334         mutex_unlock(&driver_data.ipmi_lock);
335         put_device(smi_data.dev);
336         return;
337 }
338
339 static void ipmi_bmc_gone(int iface)
340 {
341         struct acpi_ipmi_device *ipmi_device, *temp;
342
343         mutex_lock(&driver_data.ipmi_lock);
344         list_for_each_entry_safe(ipmi_device, temp,
345                                 &driver_data.ipmi_devices, head) {
346                 if (ipmi_device->ipmi_ifnum != iface)
347                         continue;
348
349                 acpi_remove_ipmi_device(ipmi_device);
350                 put_device(ipmi_device->smi_data.dev);
351                 kfree(ipmi_device);
352                 break;
353         }
354         mutex_unlock(&driver_data.ipmi_lock);
355 }
356 /* --------------------------------------------------------------------------
357  *                      Address Space Management
358  * -------------------------------------------------------------------------- */
359 /*
360  * This is the IPMI opregion space handler.
361  * @function: indicates the read/write. In fact as the IPMI message is driven
362  * by command, only write is meaningful.
363  * @address: This contains the netfn/command of IPMI request message.
364  * @bits   : not used.
365  * @value  : it is an in/out parameter. It points to the IPMI message buffer.
366  *           Before the IPMI message is sent, it represents the actual request
367  *           IPMI message. After the IPMI message is finished, it represents
368  *           the response IPMI message returned by IPMI command.
369  * @handler_context: IPMI device context.
370  */
371
372 static acpi_status
373 acpi_ipmi_space_handler(u32 function, acpi_physical_address address,
374                       u32 bits, acpi_integer *value,
375                       void *handler_context, void *region_context)
376 {
377         struct acpi_ipmi_msg *tx_msg;
378         struct acpi_ipmi_device *ipmi_device = handler_context;
379         int err, rem_time;
380         acpi_status status;
381         /*
382          * IPMI opregion message.
383          * IPMI message is firstly written to the BMC and system software
384          * can get the respsonse. So it is unmeaningful for the read access
385          * of IPMI opregion.
386          */
387         if ((function & ACPI_IO_MASK) == ACPI_READ)
388                 return AE_TYPE;
389
390         if (!ipmi_device->user_interface)
391                 return AE_NOT_EXIST;
392
393         tx_msg = acpi_alloc_ipmi_msg(ipmi_device);
394         if (!tx_msg)
395                 return AE_NO_MEMORY;
396
397         acpi_format_ipmi_msg(tx_msg, address, value);
398         mutex_lock(&ipmi_device->tx_msg_lock);
399         list_add_tail(&tx_msg->head, &ipmi_device->tx_msg_list);
400         mutex_unlock(&ipmi_device->tx_msg_lock);
401         err = ipmi_request_settime(ipmi_device->user_interface,
402                                         &tx_msg->addr,
403                                         tx_msg->tx_msgid,
404                                         &tx_msg->tx_message,
405                                         NULL, 0, 0, 0);
406         if (err) {
407                 status = AE_ERROR;
408                 goto end_label;
409         }
410         rem_time = wait_for_completion_timeout(&tx_msg->tx_complete,
411                                         IPMI_TIMEOUT);
412         acpi_format_ipmi_response(tx_msg, value, rem_time);
413         status = AE_OK;
414
415 end_label:
416         mutex_lock(&ipmi_device->tx_msg_lock);
417         list_del(&tx_msg->head);
418         mutex_unlock(&ipmi_device->tx_msg_lock);
419         kfree(tx_msg);
420         return status;
421 }
422
423 static void ipmi_remove_space_handler(struct acpi_ipmi_device *ipmi)
424 {
425         if (!test_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags))
426                 return;
427
428         acpi_remove_address_space_handler(ipmi->handle,
429                                 ACPI_ADR_SPACE_IPMI, &acpi_ipmi_space_handler);
430
431         clear_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags);
432 }
433
434 static int ipmi_install_space_handler(struct acpi_ipmi_device *ipmi)
435 {
436         acpi_status status;
437
438         if (test_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags))
439                 return 0;
440
441         status = acpi_install_address_space_handler(ipmi->handle,
442                                                     ACPI_ADR_SPACE_IPMI,
443                                                     &acpi_ipmi_space_handler,
444                                                     NULL, ipmi);
445         if (ACPI_FAILURE(status)) {
446                 struct pnp_dev *pnp_dev = ipmi->pnp_dev;
447                 dev_warn(&pnp_dev->dev, "Can't register IPMI opregion space "
448                         "handle\n");
449                 return -EINVAL;
450         }
451         set_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags);
452         return 0;
453 }
454
455 static void acpi_add_ipmi_device(struct acpi_ipmi_device *ipmi_device)
456 {
457
458         INIT_LIST_HEAD(&ipmi_device->head);
459
460         mutex_init(&ipmi_device->tx_msg_lock);
461         INIT_LIST_HEAD(&ipmi_device->tx_msg_list);
462         ipmi_install_space_handler(ipmi_device);
463
464         list_add_tail(&ipmi_device->head, &driver_data.ipmi_devices);
465 }
466
467 static void acpi_remove_ipmi_device(struct acpi_ipmi_device *ipmi_device)
468 {
469         /*
470          * If the IPMI user interface is created, it should be
471          * destroyed.
472          */
473         if (ipmi_device->user_interface) {
474                 ipmi_destroy_user(ipmi_device->user_interface);
475                 ipmi_device->user_interface = NULL;
476         }
477         /* flush the Tx_msg list */
478         if (!list_empty(&ipmi_device->tx_msg_list))
479                 ipmi_flush_tx_msg(ipmi_device);
480
481         list_del(&ipmi_device->head);
482         ipmi_remove_space_handler(ipmi_device);
483 }
484
485 static int __init acpi_ipmi_init(void)
486 {
487         int result = 0;
488
489         if (acpi_disabled)
490                 return result;
491
492         mutex_init(&driver_data.ipmi_lock);
493
494         result = ipmi_smi_watcher_register(&driver_data.bmc_events);
495
496         return result;
497 }
498
499 static void __exit acpi_ipmi_exit(void)
500 {
501         struct acpi_ipmi_device *ipmi_device, *temp;
502
503         if (acpi_disabled)
504                 return;
505
506         ipmi_smi_watcher_unregister(&driver_data.bmc_events);
507
508         /*
509          * When one smi_watcher is unregistered, it is only deleted
510          * from the smi_watcher list. But the smi_gone callback function
511          * is not called. So explicitly uninstall the ACPI IPMI oregion
512          * handler and free it.
513          */
514         mutex_lock(&driver_data.ipmi_lock);
515         list_for_each_entry_safe(ipmi_device, temp,
516                                 &driver_data.ipmi_devices, head) {
517                 acpi_remove_ipmi_device(ipmi_device);
518                 put_device(ipmi_device->smi_data.dev);
519                 kfree(ipmi_device);
520         }
521         mutex_unlock(&driver_data.ipmi_lock);
522 }
523
524 module_init(acpi_ipmi_init);
525 module_exit(acpi_ipmi_exit);