1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * ipmi_ssif.c
4 *
5 * The interface to the IPMI driver for SMBus access to a SMBus
6 * compliant device. Called SSIF by the IPMI spec.
7 *
8 * Author: Intel Corporation
9 * Todd Davis <todd.c.davis@intel.com>
10 *
11 * Rewritten by Corey Minyard <minyard@acm.org> to support the
12 * non-blocking I2C interface, add support for multi-part
13 * transactions, add PEC support, and general clenaup.
14 *
15 * Copyright 2003 Intel Corporation
16 * Copyright 2005 MontaVista Software
17 */
18
19 /*
20 * This file holds the "policy" for the interface to the SSIF state
21 * machine. It does the configuration, handles timers and interrupts,
22 * and drives the real SSIF state machine.
23 */
24
25 #define pr_fmt(fmt) "ipmi_ssif: " fmt
26 #define dev_fmt(fmt) "ipmi_ssif: " fmt
27
28 #if defined(MODVERSIONS)
29 #include <linux/modversions.h>
30 #endif
31
32 #include <linux/module.h>
33 #include <linux/moduleparam.h>
34 #include <linux/sched.h>
35 #include <linux/seq_file.h>
36 #include <linux/timer.h>
37 #include <linux/delay.h>
38 #include <linux/errno.h>
39 #include <linux/spinlock.h>
40 #include <linux/slab.h>
41 #include <linux/list.h>
42 #include <linux/i2c.h>
43 #include <linux/ipmi_smi.h>
44 #include <linux/init.h>
45 #include <linux/dmi.h>
46 #include <linux/kthread.h>
47 #include <linux/acpi.h>
48 #include <linux/ctype.h>
49 #include <linux/time64.h>
50 #include "ipmi_dmi.h"
51
52 #define DEVICE_NAME "ipmi_ssif"
53
54 #define IPMI_GET_SYSTEM_INTERFACE_CAPABILITIES_CMD 0x57
55
56 #define SSIF_IPMI_REQUEST 2
57 #define SSIF_IPMI_MULTI_PART_REQUEST_START 6
58 #define SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE 7
59 #define SSIF_IPMI_MULTI_PART_REQUEST_END 8
60 #define SSIF_IPMI_RESPONSE 3
61 #define SSIF_IPMI_MULTI_PART_RESPONSE_MIDDLE 9
62
63 /* ssif_debug is a bit-field
64 * SSIF_DEBUG_MSG - commands and their responses
65 * SSIF_DEBUG_STATES - message states
66 * SSIF_DEBUG_TIMING - Measure times between events in the driver
67 */
68 #define SSIF_DEBUG_TIMING 4
69 #define SSIF_DEBUG_STATE 2
70 #define SSIF_DEBUG_MSG 1
71 #define SSIF_NODEBUG 0
72 #define SSIF_DEFAULT_DEBUG (SSIF_NODEBUG)
73
74 /*
75 * Timer values
76 */
77 #define SSIF_MSG_USEC 60000 /* 60ms between message tries (T3). */
78 #define SSIF_REQ_RETRY_USEC 60000 /* 60ms between send retries (T6). */
79 #define SSIF_MSG_PART_USEC 5000 /* 5ms for a message part */
80
81 /* How many times to we retry sending/receiving the message. */
82 #define SSIF_SEND_RETRIES 5
83 #define SSIF_RECV_RETRIES 250
84
85 #define SSIF_MSG_MSEC (SSIF_MSG_USEC / 1000)
86 #define SSIF_REQ_RETRY_MSEC (SSIF_REQ_RETRY_USEC / 1000)
87 #define SSIF_MSG_JIFFIES ((SSIF_MSG_USEC * 1000) / TICK_NSEC)
88 #define SSIF_REQ_RETRY_JIFFIES ((SSIF_REQ_RETRY_USEC * 1000) / TICK_NSEC)
89 #define SSIF_MSG_PART_JIFFIES ((SSIF_MSG_PART_USEC * 1000) / TICK_NSEC)
90
91 /*
92 * Timeout for the watch, only used for get flag timer.
93 */
94 #define SSIF_WATCH_MSG_TIMEOUT msecs_to_jiffies(10)
95 #define SSIF_WATCH_WATCHDOG_TIMEOUT msecs_to_jiffies(250)
96
97 enum ssif_intf_state {
98 SSIF_IDLE,
99 SSIF_GETTING_FLAGS,
100 SSIF_GETTING_EVENTS,
101 SSIF_CLEARING_FLAGS,
102 SSIF_GETTING_MESSAGES,
103 /* FIXME - add watchdog stuff. */
104 };
105
106 #define IS_SSIF_IDLE(ssif) ((ssif)->ssif_state == SSIF_IDLE \
107 && (ssif)->curr_msg == NULL)
108
109 /*
110 * Indexes into stats[] in ssif_info below.
111 */
112 enum ssif_stat_indexes {
113 /* Number of total messages sent. */
114 SSIF_STAT_sent_messages = 0,
115
116 /*
117 * Number of message parts sent. Messages may be broken into
118 * parts if they are long.
119 */
120 SSIF_STAT_sent_messages_parts,
121
122 /*
123 * Number of time a message was retried.
124 */
125 SSIF_STAT_send_retries,
126
127 /*
128 * Number of times the send of a message failed.
129 */
130 SSIF_STAT_send_errors,
131
132 /*
133 * Number of message responses received.
134 */
135 SSIF_STAT_received_messages,
136
137 /*
138 * Number of message fragments received.
139 */
140 SSIF_STAT_received_message_parts,
141
142 /*
143 * Number of times the receive of a message was retried.
144 */
145 SSIF_STAT_receive_retries,
146
147 /*
148 * Number of errors receiving messages.
149 */
150 SSIF_STAT_receive_errors,
151
152 /*
153 * Number of times a flag fetch was requested.
154 */
155 SSIF_STAT_flag_fetches,
156
157 /*
158 * Number of times the hardware didn't follow the state machine.
159 */
160 SSIF_STAT_hosed,
161
162 /*
163 * Number of received events.
164 */
165 SSIF_STAT_events,
166
167 /* Number of asyncronous messages received. */
168 SSIF_STAT_incoming_messages,
169
170 /* Number of watchdog pretimeouts. */
171 SSIF_STAT_watchdog_pretimeouts,
172
173 /* Number of alers received. */
174 SSIF_STAT_alerts,
175
176 /* Always add statistics before this value, it must be last. */
177 SSIF_NUM_STATS
178 };
179
180 struct ssif_addr_info {
181 struct i2c_board_info binfo;
182 char *adapter_name;
183 int debug;
184 int slave_addr;
185 enum ipmi_addr_src addr_src;
186 union ipmi_smi_info_union addr_info;
187 struct device *dev;
188 struct i2c_client *client;
189
190 struct mutex clients_mutex;
191 struct list_head clients;
192
193 struct list_head link;
194 };
195
196 struct ssif_info;
197
198 typedef void (*ssif_i2c_done)(struct ssif_info *ssif_info, int result,
199 unsigned char *data, unsigned int len);
200
201 struct ssif_info {
202 struct ipmi_smi *intf;
203 spinlock_t lock;
204 struct ipmi_smi_msg *waiting_msg;
205 struct ipmi_smi_msg *curr_msg;
206 enum ssif_intf_state ssif_state;
207 unsigned long ssif_debug;
208
209 struct ipmi_smi_handlers handlers;
210
211 enum ipmi_addr_src addr_source; /* ACPI, PCI, SMBIOS, hardcode, etc. */
212 union ipmi_smi_info_union addr_info;
213
214 /*
215 * Flags from the last GET_MSG_FLAGS command, used when an ATTN
216 * is set to hold the flags until we are done handling everything
217 * from the flags.
218 */
219 #define RECEIVE_MSG_AVAIL 0x01
220 #define EVENT_MSG_BUFFER_FULL 0x02
221 #define WDT_PRE_TIMEOUT_INT 0x08
222 unsigned char msg_flags;
223
224 u8 global_enables;
225 bool has_event_buffer;
226 bool supports_alert;
227
228 /*
229 * Used to tell what we should do with alerts. If we are
230 * waiting on a response, read the data immediately.
231 */
232 bool got_alert;
233 bool waiting_alert;
234
235 /* Used to inform the timeout that it should do a resend. */
236 bool do_resend;
237
238 /*
239 * If set to true, this will request events the next time the
240 * state machine is idle.
241 */
242 bool req_events;
243
244 /*
245 * If set to true, this will request flags the next time the
246 * state machine is idle.
247 */
248 bool req_flags;
249
250 /* Used for sending/receiving data. +1 for the length. */
251 unsigned char data[IPMI_MAX_MSG_LENGTH + 1];
252 unsigned int data_len;
253
254 /* Temp receive buffer, gets copied into data. */
255 unsigned char recv[I2C_SMBUS_BLOCK_MAX];
256
257 struct i2c_client *client;
258 ssif_i2c_done done_handler;
259
260 /* Thread interface handling */
261 struct task_struct *thread;
262 struct completion wake_thread;
263 bool stopping;
264 int i2c_read_write;
265 int i2c_command;
266 unsigned char *i2c_data;
267 unsigned int i2c_size;
268
269 struct timer_list retry_timer;
270 int retries_left;
271
272 long watch_timeout; /* Timeout for flags check, 0 if off. */
273 struct timer_list watch_timer; /* Flag fetch timer. */
274
275 /* Info from SSIF cmd */
276 unsigned char max_xmit_msg_size;
277 unsigned char max_recv_msg_size;
278 bool cmd8_works; /* See test_multipart_messages() for details. */
279 unsigned int multi_support;
280 int supports_pec;
281
282 #define SSIF_NO_MULTI 0
283 #define SSIF_MULTI_2_PART 1
284 #define SSIF_MULTI_n_PART 2
285 unsigned char *multi_data;
286 unsigned int multi_len;
287 unsigned int multi_pos;
288
289 atomic_t stats[SSIF_NUM_STATS];
290 };
291
292 #define ssif_inc_stat(ssif, stat) \
293 atomic_inc(&(ssif)->stats[SSIF_STAT_ ## stat])
294 #define ssif_get_stat(ssif, stat) \
295 ((unsigned int) atomic_read(&(ssif)->stats[SSIF_STAT_ ## stat]))
296
297 static bool initialized;
298 static bool platform_registered;
299
300 static void return_hosed_msg(struct ssif_info *ssif_info,
301 struct ipmi_smi_msg *msg);
302 static void start_next_msg(struct ssif_info *ssif_info, unsigned long *flags);
303 static int start_send(struct ssif_info *ssif_info,
304 unsigned char *data,
305 unsigned int len);
306
ipmi_ssif_lock_cond(struct ssif_info * ssif_info,unsigned long * flags)307 static unsigned long *ipmi_ssif_lock_cond(struct ssif_info *ssif_info,
308 unsigned long *flags)
309 __acquires(&ssif_info->lock)
310 {
311 spin_lock_irqsave(&ssif_info->lock, *flags);
312 return flags;
313 }
314
ipmi_ssif_unlock_cond(struct ssif_info * ssif_info,unsigned long * flags)315 static void ipmi_ssif_unlock_cond(struct ssif_info *ssif_info,
316 unsigned long *flags)
317 __releases(&ssif_info->lock)
318 {
319 spin_unlock_irqrestore(&ssif_info->lock, *flags);
320 }
321
deliver_recv_msg(struct ssif_info * ssif_info,struct ipmi_smi_msg * msg)322 static void deliver_recv_msg(struct ssif_info *ssif_info,
323 struct ipmi_smi_msg *msg)
324 {
325 if (msg->rsp_size < 0) {
326 return_hosed_msg(ssif_info, msg);
327 dev_err(&ssif_info->client->dev,
328 "%s: Malformed message: rsp_size = %d\n",
329 __func__, msg->rsp_size);
330 } else {
331 ipmi_smi_msg_received(ssif_info->intf, msg);
332 }
333 }
334
return_hosed_msg(struct ssif_info * ssif_info,struct ipmi_smi_msg * msg)335 static void return_hosed_msg(struct ssif_info *ssif_info,
336 struct ipmi_smi_msg *msg)
337 {
338 ssif_inc_stat(ssif_info, hosed);
339
340 /* Make it a response */
341 msg->rsp[0] = msg->data[0] | 4;
342 msg->rsp[1] = msg->data[1];
343 msg->rsp[2] = 0xFF; /* Unknown error. */
344 msg->rsp_size = 3;
345
346 deliver_recv_msg(ssif_info, msg);
347 }
348
349 /*
350 * Must be called with the message lock held. This will release the
351 * message lock. Note that the caller will check IS_SSIF_IDLE and
352 * start a new operation, so there is no need to check for new
353 * messages to start in here.
354 */
start_clear_flags(struct ssif_info * ssif_info,unsigned long * flags)355 static void start_clear_flags(struct ssif_info *ssif_info, unsigned long *flags)
356 {
357 unsigned char msg[3];
358
359 ssif_info->msg_flags &= ~WDT_PRE_TIMEOUT_INT;
360 ssif_info->ssif_state = SSIF_CLEARING_FLAGS;
361 ipmi_ssif_unlock_cond(ssif_info, flags);
362
363 /* Make sure the watchdog pre-timeout flag is not set at startup. */
364 msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
365 msg[1] = IPMI_CLEAR_MSG_FLAGS_CMD;
366 msg[2] = WDT_PRE_TIMEOUT_INT;
367
368 if (start_send(ssif_info, msg, 3) != 0) {
369 /* Error, just go to normal state. */
370 ssif_info->ssif_state = SSIF_IDLE;
371 }
372 }
373
start_flag_fetch(struct ssif_info * ssif_info,unsigned long * flags)374 static void start_flag_fetch(struct ssif_info *ssif_info, unsigned long *flags)
375 {
376 unsigned char mb[2];
377
378 ssif_info->req_flags = false;
379 ssif_info->ssif_state = SSIF_GETTING_FLAGS;
380 ipmi_ssif_unlock_cond(ssif_info, flags);
381
382 mb[0] = (IPMI_NETFN_APP_REQUEST << 2);
383 mb[1] = IPMI_GET_MSG_FLAGS_CMD;
384 if (start_send(ssif_info, mb, 2) != 0)
385 ssif_info->ssif_state = SSIF_IDLE;
386 }
387
check_start_send(struct ssif_info * ssif_info,unsigned long * flags,struct ipmi_smi_msg * msg)388 static void check_start_send(struct ssif_info *ssif_info, unsigned long *flags,
389 struct ipmi_smi_msg *msg)
390 {
391 if (start_send(ssif_info, msg->data, msg->data_size) != 0) {
392 unsigned long oflags;
393
394 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
395 ssif_info->curr_msg = NULL;
396 ssif_info->ssif_state = SSIF_IDLE;
397 ipmi_ssif_unlock_cond(ssif_info, flags);
398 ipmi_free_smi_msg(msg);
399 }
400 }
401
start_event_fetch(struct ssif_info * ssif_info,unsigned long * flags)402 static void start_event_fetch(struct ssif_info *ssif_info, unsigned long *flags)
403 {
404 struct ipmi_smi_msg *msg;
405
406 ssif_info->req_events = false;
407
408 msg = ipmi_alloc_smi_msg();
409 if (!msg) {
410 ssif_info->ssif_state = SSIF_IDLE;
411 ipmi_ssif_unlock_cond(ssif_info, flags);
412 return;
413 }
414
415 ssif_info->curr_msg = msg;
416 ssif_info->ssif_state = SSIF_GETTING_EVENTS;
417 ipmi_ssif_unlock_cond(ssif_info, flags);
418
419 msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
420 msg->data[1] = IPMI_READ_EVENT_MSG_BUFFER_CMD;
421 msg->data_size = 2;
422
423 check_start_send(ssif_info, flags, msg);
424 }
425
start_recv_msg_fetch(struct ssif_info * ssif_info,unsigned long * flags)426 static void start_recv_msg_fetch(struct ssif_info *ssif_info,
427 unsigned long *flags)
428 {
429 struct ipmi_smi_msg *msg;
430
431 msg = ipmi_alloc_smi_msg();
432 if (!msg) {
433 ssif_info->ssif_state = SSIF_IDLE;
434 ipmi_ssif_unlock_cond(ssif_info, flags);
435 return;
436 }
437
438 ssif_info->curr_msg = msg;
439 ssif_info->ssif_state = SSIF_GETTING_MESSAGES;
440 ipmi_ssif_unlock_cond(ssif_info, flags);
441
442 msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
443 msg->data[1] = IPMI_GET_MSG_CMD;
444 msg->data_size = 2;
445
446 check_start_send(ssif_info, flags, msg);
447 }
448
449 /*
450 * Must be called with the message lock held. This will release the
451 * message lock. Note that the caller will check IS_SSIF_IDLE and
452 * start a new operation, so there is no need to check for new
453 * messages to start in here.
454 */
handle_flags(struct ssif_info * ssif_info,unsigned long * flags)455 static void handle_flags(struct ssif_info *ssif_info, unsigned long *flags)
456 {
457 if (ssif_info->msg_flags & WDT_PRE_TIMEOUT_INT) {
458 /* Watchdog pre-timeout */
459 ssif_inc_stat(ssif_info, watchdog_pretimeouts);
460 start_clear_flags(ssif_info, flags);
461 ipmi_smi_watchdog_pretimeout(ssif_info->intf);
462 } else if (ssif_info->msg_flags & RECEIVE_MSG_AVAIL)
463 /* Messages available. */
464 start_recv_msg_fetch(ssif_info, flags);
465 else if (ssif_info->msg_flags & EVENT_MSG_BUFFER_FULL)
466 /* Events available. */
467 start_event_fetch(ssif_info, flags);
468 else {
469 ssif_info->ssif_state = SSIF_IDLE;
470 ipmi_ssif_unlock_cond(ssif_info, flags);
471 }
472 }
473
ipmi_ssif_thread(void * data)474 static int ipmi_ssif_thread(void *data)
475 {
476 struct ssif_info *ssif_info = data;
477
478 while (!kthread_should_stop()) {
479 int result;
480
481 /* Wait for something to do */
482 result = wait_for_completion_interruptible(
483 &ssif_info->wake_thread);
484 if (ssif_info->stopping)
485 break;
486 if (result == -ERESTARTSYS)
487 continue;
488 init_completion(&ssif_info->wake_thread);
489
490 if (ssif_info->i2c_read_write == I2C_SMBUS_WRITE) {
491 result = i2c_smbus_write_block_data(
492 ssif_info->client, ssif_info->i2c_command,
493 ssif_info->i2c_data[0],
494 ssif_info->i2c_data + 1);
495 ssif_info->done_handler(ssif_info, result, NULL, 0);
496 } else {
497 result = i2c_smbus_read_block_data(
498 ssif_info->client, ssif_info->i2c_command,
499 ssif_info->i2c_data);
500 if (result < 0)
501 ssif_info->done_handler(ssif_info, result,
502 NULL, 0);
503 else
504 ssif_info->done_handler(ssif_info, 0,
505 ssif_info->i2c_data,
506 result);
507 }
508 }
509
510 return 0;
511 }
512
ssif_i2c_send(struct ssif_info * ssif_info,ssif_i2c_done handler,int read_write,int command,unsigned char * data,unsigned int size)513 static void ssif_i2c_send(struct ssif_info *ssif_info,
514 ssif_i2c_done handler,
515 int read_write, int command,
516 unsigned char *data, unsigned int size)
517 {
518 ssif_info->done_handler = handler;
519
520 ssif_info->i2c_read_write = read_write;
521 ssif_info->i2c_command = command;
522 ssif_info->i2c_data = data;
523 ssif_info->i2c_size = size;
524 complete(&ssif_info->wake_thread);
525 }
526
527
528 static void msg_done_handler(struct ssif_info *ssif_info, int result,
529 unsigned char *data, unsigned int len);
530
start_get(struct ssif_info * ssif_info)531 static void start_get(struct ssif_info *ssif_info)
532 {
533 ssif_info->multi_pos = 0;
534
535 ssif_i2c_send(ssif_info, msg_done_handler, I2C_SMBUS_READ,
536 SSIF_IPMI_RESPONSE,
537 ssif_info->recv, I2C_SMBUS_BLOCK_DATA);
538 }
539
540 static void start_resend(struct ssif_info *ssif_info);
541
retry_timeout(struct timer_list * t)542 static void retry_timeout(struct timer_list *t)
543 {
544 struct ssif_info *ssif_info = from_timer(ssif_info, t, retry_timer);
545 unsigned long oflags, *flags;
546 bool waiting, resend;
547
548 if (ssif_info->stopping)
549 return;
550
551 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
552 resend = ssif_info->do_resend;
553 ssif_info->do_resend = false;
554 waiting = ssif_info->waiting_alert;
555 ssif_info->waiting_alert = false;
556 ipmi_ssif_unlock_cond(ssif_info, flags);
557
558 if (waiting)
559 start_get(ssif_info);
560 if (resend)
561 start_resend(ssif_info);
562 }
563
watch_timeout(struct timer_list * t)564 static void watch_timeout(struct timer_list *t)
565 {
566 struct ssif_info *ssif_info = from_timer(ssif_info, t, watch_timer);
567 unsigned long oflags, *flags;
568
569 if (ssif_info->stopping)
570 return;
571
572 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
573 if (ssif_info->watch_timeout) {
574 mod_timer(&ssif_info->watch_timer,
575 jiffies + ssif_info->watch_timeout);
576 if (IS_SSIF_IDLE(ssif_info)) {
577 start_flag_fetch(ssif_info, flags); /* Releases lock */
578 return;
579 }
580 ssif_info->req_flags = true;
581 }
582 ipmi_ssif_unlock_cond(ssif_info, flags);
583 }
584
ssif_alert(struct i2c_client * client,enum i2c_alert_protocol type,unsigned int data)585 static void ssif_alert(struct i2c_client *client, enum i2c_alert_protocol type,
586 unsigned int data)
587 {
588 struct ssif_info *ssif_info = i2c_get_clientdata(client);
589 unsigned long oflags, *flags;
590 bool do_get = false;
591
592 if (type != I2C_PROTOCOL_SMBUS_ALERT)
593 return;
594
595 ssif_inc_stat(ssif_info, alerts);
596
597 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
598 if (ssif_info->waiting_alert) {
599 ssif_info->waiting_alert = false;
600 del_timer(&ssif_info->retry_timer);
601 do_get = true;
602 } else if (ssif_info->curr_msg) {
603 ssif_info->got_alert = true;
604 }
605 ipmi_ssif_unlock_cond(ssif_info, flags);
606 if (do_get)
607 start_get(ssif_info);
608 }
609
msg_done_handler(struct ssif_info * ssif_info,int result,unsigned char * data,unsigned int len)610 static void msg_done_handler(struct ssif_info *ssif_info, int result,
611 unsigned char *data, unsigned int len)
612 {
613 struct ipmi_smi_msg *msg;
614 unsigned long oflags, *flags;
615
616 /*
617 * We are single-threaded here, so no need for a lock until we
618 * start messing with driver states or the queues.
619 */
620
621 if (result < 0) {
622 ssif_info->retries_left--;
623 if (ssif_info->retries_left > 0) {
624 ssif_inc_stat(ssif_info, receive_retries);
625
626 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
627 ssif_info->waiting_alert = true;
628 if (!ssif_info->stopping)
629 mod_timer(&ssif_info->retry_timer,
630 jiffies + SSIF_MSG_JIFFIES);
631 ipmi_ssif_unlock_cond(ssif_info, flags);
632 return;
633 }
634
635 ssif_inc_stat(ssif_info, receive_errors);
636
637 if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
638 dev_dbg(&ssif_info->client->dev,
639 "%s: Error %d\n", __func__, result);
640 len = 0;
641 goto continue_op;
642 }
643
644 if ((len > 1) && (ssif_info->multi_pos == 0)
645 && (data[0] == 0x00) && (data[1] == 0x01)) {
646 /* Start of multi-part read. Start the next transaction. */
647 int i;
648
649 ssif_inc_stat(ssif_info, received_message_parts);
650
651 /* Remove the multi-part read marker. */
652 len -= 2;
653 data += 2;
654 for (i = 0; i < len; i++)
655 ssif_info->data[i] = data[i];
656 ssif_info->multi_len = len;
657 ssif_info->multi_pos = 1;
658
659 ssif_i2c_send(ssif_info, msg_done_handler, I2C_SMBUS_READ,
660 SSIF_IPMI_MULTI_PART_RESPONSE_MIDDLE,
661 ssif_info->recv, I2C_SMBUS_BLOCK_DATA);
662 return;
663 } else if (ssif_info->multi_pos) {
664 /* Middle of multi-part read. Start the next transaction. */
665 int i;
666 unsigned char blocknum;
667
668 if (len == 0) {
669 result = -EIO;
670 if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
671 dev_dbg(&ssif_info->client->dev,
672 "Middle message with no data\n");
673
674 goto continue_op;
675 }
676
677 blocknum = data[0];
678 len--;
679 data++;
680
681 if (blocknum != 0xff && len != 31) {
682 /* All blocks but the last must have 31 data bytes. */
683 result = -EIO;
684 if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
685 dev_dbg(&ssif_info->client->dev,
686 "Received middle message <31\n");
687
688 goto continue_op;
689 }
690
691 if (ssif_info->multi_len + len > IPMI_MAX_MSG_LENGTH) {
692 /* Received message too big, abort the operation. */
693 result = -E2BIG;
694 if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
695 dev_dbg(&ssif_info->client->dev,
696 "Received message too big\n");
697
698 goto continue_op;
699 }
700
701 for (i = 0; i < len; i++)
702 ssif_info->data[i + ssif_info->multi_len] = data[i];
703 ssif_info->multi_len += len;
704 if (blocknum == 0xff) {
705 /* End of read */
706 len = ssif_info->multi_len;
707 data = ssif_info->data;
708 } else if (blocknum + 1 != ssif_info->multi_pos) {
709 /*
710 * Out of sequence block, just abort. Block
711 * numbers start at zero for the second block,
712 * but multi_pos starts at one, so the +1.
713 */
714 if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
715 dev_dbg(&ssif_info->client->dev,
716 "Received message out of sequence, expected %u, got %u\n",
717 ssif_info->multi_pos - 1, blocknum);
718 result = -EIO;
719 } else {
720 ssif_inc_stat(ssif_info, received_message_parts);
721
722 ssif_info->multi_pos++;
723
724 ssif_i2c_send(ssif_info, msg_done_handler,
725 I2C_SMBUS_READ,
726 SSIF_IPMI_MULTI_PART_RESPONSE_MIDDLE,
727 ssif_info->recv,
728 I2C_SMBUS_BLOCK_DATA);
729 return;
730 }
731 }
732
733 continue_op:
734 if (result < 0) {
735 ssif_inc_stat(ssif_info, receive_errors);
736 } else {
737 ssif_inc_stat(ssif_info, received_messages);
738 ssif_inc_stat(ssif_info, received_message_parts);
739 }
740
741 if (ssif_info->ssif_debug & SSIF_DEBUG_STATE)
742 dev_dbg(&ssif_info->client->dev,
743 "DONE 1: state = %d, result=%d\n",
744 ssif_info->ssif_state, result);
745
746 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
747 msg = ssif_info->curr_msg;
748 if (msg) {
749 if (data) {
750 if (len > IPMI_MAX_MSG_LENGTH)
751 len = IPMI_MAX_MSG_LENGTH;
752 memcpy(msg->rsp, data, len);
753 } else {
754 len = 0;
755 }
756 msg->rsp_size = len;
757 ssif_info->curr_msg = NULL;
758 }
759
760 switch (ssif_info->ssif_state) {
761 case SSIF_IDLE:
762 ipmi_ssif_unlock_cond(ssif_info, flags);
763 if (!msg)
764 break;
765
766 if (result < 0)
767 return_hosed_msg(ssif_info, msg);
768 else
769 deliver_recv_msg(ssif_info, msg);
770 break;
771
772 case SSIF_GETTING_FLAGS:
773 /* We got the flags from the SSIF, now handle them. */
774 if ((result < 0) || (len < 4) || (data[2] != 0)) {
775 /*
776 * Error fetching flags, or invalid length,
777 * just give up for now.
778 */
779 ssif_info->ssif_state = SSIF_IDLE;
780 ipmi_ssif_unlock_cond(ssif_info, flags);
781 dev_warn(&ssif_info->client->dev,
782 "Error getting flags: %d %d, %x\n",
783 result, len, (len >= 3) ? data[2] : 0);
784 } else if (data[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2
785 || data[1] != IPMI_GET_MSG_FLAGS_CMD) {
786 /*
787 * Don't abort here, maybe it was a queued
788 * response to a previous command.
789 */
790 ipmi_ssif_unlock_cond(ssif_info, flags);
791 dev_warn(&ssif_info->client->dev,
792 "Invalid response getting flags: %x %x\n",
793 data[0], data[1]);
794 } else {
795 ssif_inc_stat(ssif_info, flag_fetches);
796 ssif_info->msg_flags = data[3];
797 handle_flags(ssif_info, flags);
798 }
799 break;
800
801 case SSIF_CLEARING_FLAGS:
802 /* We cleared the flags. */
803 if ((result < 0) || (len < 3) || (data[2] != 0)) {
804 /* Error clearing flags */
805 dev_warn(&ssif_info->client->dev,
806 "Error clearing flags: %d %d, %x\n",
807 result, len, (len >= 3) ? data[2] : 0);
808 } else if (data[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2
809 || data[1] != IPMI_CLEAR_MSG_FLAGS_CMD) {
810 dev_warn(&ssif_info->client->dev,
811 "Invalid response clearing flags: %x %x\n",
812 data[0], data[1]);
813 }
814 ssif_info->ssif_state = SSIF_IDLE;
815 ipmi_ssif_unlock_cond(ssif_info, flags);
816 break;
817
818 case SSIF_GETTING_EVENTS:
819 if (!msg) {
820 /* Should never happen, but just in case. */
821 dev_warn(&ssif_info->client->dev,
822 "No message set while getting events\n");
823 ipmi_ssif_unlock_cond(ssif_info, flags);
824 break;
825 }
826
827 if ((result < 0) || (len < 3) || (msg->rsp[2] != 0)) {
828 /* Error getting event, probably done. */
829 msg->done(msg);
830
831 /* Take off the event flag. */
832 ssif_info->msg_flags &= ~EVENT_MSG_BUFFER_FULL;
833 handle_flags(ssif_info, flags);
834 } else if (msg->rsp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2
835 || msg->rsp[1] != IPMI_READ_EVENT_MSG_BUFFER_CMD) {
836 dev_warn(&ssif_info->client->dev,
837 "Invalid response getting events: %x %x\n",
838 msg->rsp[0], msg->rsp[1]);
839 msg->done(msg);
840 /* Take off the event flag. */
841 ssif_info->msg_flags &= ~EVENT_MSG_BUFFER_FULL;
842 handle_flags(ssif_info, flags);
843 } else {
844 handle_flags(ssif_info, flags);
845 ssif_inc_stat(ssif_info, events);
846 deliver_recv_msg(ssif_info, msg);
847 }
848 break;
849
850 case SSIF_GETTING_MESSAGES:
851 if (!msg) {
852 /* Should never happen, but just in case. */
853 dev_warn(&ssif_info->client->dev,
854 "No message set while getting messages\n");
855 ipmi_ssif_unlock_cond(ssif_info, flags);
856 break;
857 }
858
859 if ((result < 0) || (len < 3) || (msg->rsp[2] != 0)) {
860 /* Error getting event, probably done. */
861 msg->done(msg);
862
863 /* Take off the msg flag. */
864 ssif_info->msg_flags &= ~RECEIVE_MSG_AVAIL;
865 handle_flags(ssif_info, flags);
866 } else if (msg->rsp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2
867 || msg->rsp[1] != IPMI_GET_MSG_CMD) {
868 dev_warn(&ssif_info->client->dev,
869 "Invalid response clearing flags: %x %x\n",
870 msg->rsp[0], msg->rsp[1]);
871 msg->done(msg);
872
873 /* Take off the msg flag. */
874 ssif_info->msg_flags &= ~RECEIVE_MSG_AVAIL;
875 handle_flags(ssif_info, flags);
876 } else {
877 ssif_inc_stat(ssif_info, incoming_messages);
878 handle_flags(ssif_info, flags);
879 deliver_recv_msg(ssif_info, msg);
880 }
881 break;
882
883 default:
884 /* Should never happen, but just in case. */
885 dev_warn(&ssif_info->client->dev,
886 "Invalid state in message done handling: %d\n",
887 ssif_info->ssif_state);
888 ipmi_ssif_unlock_cond(ssif_info, flags);
889 }
890
891 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
892 if (IS_SSIF_IDLE(ssif_info) && !ssif_info->stopping) {
893 if (ssif_info->req_events)
894 start_event_fetch(ssif_info, flags);
895 else if (ssif_info->req_flags)
896 start_flag_fetch(ssif_info, flags);
897 else
898 start_next_msg(ssif_info, flags);
899 } else
900 ipmi_ssif_unlock_cond(ssif_info, flags);
901
902 if (ssif_info->ssif_debug & SSIF_DEBUG_STATE)
903 dev_dbg(&ssif_info->client->dev,
904 "DONE 2: state = %d.\n", ssif_info->ssif_state);
905 }
906
msg_written_handler(struct ssif_info * ssif_info,int result,unsigned char * data,unsigned int len)907 static void msg_written_handler(struct ssif_info *ssif_info, int result,
908 unsigned char *data, unsigned int len)
909 {
910 /* We are single-threaded here, so no need for a lock. */
911 if (result < 0) {
912 ssif_info->retries_left--;
913 if (ssif_info->retries_left > 0) {
914 /*
915 * Wait the retry timeout time per the spec,
916 * then redo the send.
917 */
918 ssif_info->do_resend = true;
919 mod_timer(&ssif_info->retry_timer,
920 jiffies + SSIF_REQ_RETRY_JIFFIES);
921 return;
922 }
923
924 ssif_inc_stat(ssif_info, send_errors);
925
926 if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
927 dev_dbg(&ssif_info->client->dev,
928 "%s: Out of retries\n", __func__);
929
930 msg_done_handler(ssif_info, -EIO, NULL, 0);
931 return;
932 }
933
934 if (ssif_info->multi_data) {
935 /*
936 * In the middle of a multi-data write. See the comment
937 * in the SSIF_MULTI_n_PART case in the probe function
938 * for details on the intricacies of this.
939 */
940 int left, to_write;
941 unsigned char *data_to_send;
942 unsigned char cmd;
943
944 ssif_inc_stat(ssif_info, sent_messages_parts);
945
946 left = ssif_info->multi_len - ssif_info->multi_pos;
947 to_write = left;
948 if (to_write > 32)
949 to_write = 32;
950 /* Length byte. */
951 ssif_info->multi_data[ssif_info->multi_pos] = to_write;
952 data_to_send = ssif_info->multi_data + ssif_info->multi_pos;
953 ssif_info->multi_pos += to_write;
954 cmd = SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE;
955 if (ssif_info->cmd8_works) {
956 if (left == to_write) {
957 cmd = SSIF_IPMI_MULTI_PART_REQUEST_END;
958 ssif_info->multi_data = NULL;
959 }
960 } else if (to_write < 32) {
961 ssif_info->multi_data = NULL;
962 }
963
964 ssif_i2c_send(ssif_info, msg_written_handler,
965 I2C_SMBUS_WRITE, cmd,
966 data_to_send, I2C_SMBUS_BLOCK_DATA);
967 } else {
968 /* Ready to request the result. */
969 unsigned long oflags, *flags;
970
971 ssif_inc_stat(ssif_info, sent_messages);
972 ssif_inc_stat(ssif_info, sent_messages_parts);
973
974 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
975 if (ssif_info->got_alert) {
976 /* The result is already ready, just start it. */
977 ssif_info->got_alert = false;
978 ipmi_ssif_unlock_cond(ssif_info, flags);
979 start_get(ssif_info);
980 } else {
981 /* Wait a jiffie then request the next message */
982 ssif_info->waiting_alert = true;
983 ssif_info->retries_left = SSIF_RECV_RETRIES;
984 if (!ssif_info->stopping)
985 mod_timer(&ssif_info->retry_timer,
986 jiffies + SSIF_MSG_PART_JIFFIES);
987 ipmi_ssif_unlock_cond(ssif_info, flags);
988 }
989 }
990 }
991
start_resend(struct ssif_info * ssif_info)992 static void start_resend(struct ssif_info *ssif_info)
993 {
994 int command;
995
996 ssif_info->got_alert = false;
997
998 if (ssif_info->data_len > 32) {
999 command = SSIF_IPMI_MULTI_PART_REQUEST_START;
1000 ssif_info->multi_data = ssif_info->data;
1001 ssif_info->multi_len = ssif_info->data_len;
1002 /*
1003 * Subtle thing, this is 32, not 33, because we will
1004 * overwrite the thing at position 32 (which was just
1005 * transmitted) with the new length.
1006 */
1007 ssif_info->multi_pos = 32;
1008 ssif_info->data[0] = 32;
1009 } else {
1010 ssif_info->multi_data = NULL;
1011 command = SSIF_IPMI_REQUEST;
1012 ssif_info->data[0] = ssif_info->data_len;
1013 }
1014
1015 ssif_i2c_send(ssif_info, msg_written_handler, I2C_SMBUS_WRITE,
1016 command, ssif_info->data, I2C_SMBUS_BLOCK_DATA);
1017 }
1018
start_send(struct ssif_info * ssif_info,unsigned char * data,unsigned int len)1019 static int start_send(struct ssif_info *ssif_info,
1020 unsigned char *data,
1021 unsigned int len)
1022 {
1023 if (len > IPMI_MAX_MSG_LENGTH)
1024 return -E2BIG;
1025 if (len > ssif_info->max_xmit_msg_size)
1026 return -E2BIG;
1027
1028 ssif_info->retries_left = SSIF_SEND_RETRIES;
1029 memcpy(ssif_info->data + 1, data, len);
1030 ssif_info->data_len = len;
1031 start_resend(ssif_info);
1032 return 0;
1033 }
1034
1035 /* Must be called with the message lock held. */
start_next_msg(struct ssif_info * ssif_info,unsigned long * flags)1036 static void start_next_msg(struct ssif_info *ssif_info, unsigned long *flags)
1037 {
1038 struct ipmi_smi_msg *msg;
1039 unsigned long oflags;
1040
1041 restart:
1042 if (!IS_SSIF_IDLE(ssif_info)) {
1043 ipmi_ssif_unlock_cond(ssif_info, flags);
1044 return;
1045 }
1046
1047 if (!ssif_info->waiting_msg) {
1048 ssif_info->curr_msg = NULL;
1049 ipmi_ssif_unlock_cond(ssif_info, flags);
1050 } else {
1051 int rv;
1052
1053 ssif_info->curr_msg = ssif_info->waiting_msg;
1054 ssif_info->waiting_msg = NULL;
1055 ipmi_ssif_unlock_cond(ssif_info, flags);
1056 rv = start_send(ssif_info,
1057 ssif_info->curr_msg->data,
1058 ssif_info->curr_msg->data_size);
1059 if (rv) {
1060 msg = ssif_info->curr_msg;
1061 ssif_info->curr_msg = NULL;
1062 return_hosed_msg(ssif_info, msg);
1063 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
1064 goto restart;
1065 }
1066 }
1067 }
1068
sender(void * send_info,struct ipmi_smi_msg * msg)1069 static void sender(void *send_info,
1070 struct ipmi_smi_msg *msg)
1071 {
1072 struct ssif_info *ssif_info = send_info;
1073 unsigned long oflags, *flags;
1074
1075 BUG_ON(ssif_info->waiting_msg);
1076 ssif_info->waiting_msg = msg;
1077
1078 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
1079 start_next_msg(ssif_info, flags);
1080
1081 if (ssif_info->ssif_debug & SSIF_DEBUG_TIMING) {
1082 struct timespec64 t;
1083
1084 ktime_get_real_ts64(&t);
1085 dev_dbg(&ssif_info->client->dev,
1086 "**Enqueue %02x %02x: %lld.%6.6ld\n",
1087 msg->data[0], msg->data[1],
1088 (long long)t.tv_sec, (long)t.tv_nsec / NSEC_PER_USEC);
1089 }
1090 }
1091
get_smi_info(void * send_info,struct ipmi_smi_info * data)1092 static int get_smi_info(void *send_info, struct ipmi_smi_info *data)
1093 {
1094 struct ssif_info *ssif_info = send_info;
1095
1096 data->addr_src = ssif_info->addr_source;
1097 data->dev = &ssif_info->client->dev;
1098 data->addr_info = ssif_info->addr_info;
1099 get_device(data->dev);
1100
1101 return 0;
1102 }
1103
1104 /*
1105 * Upper layer wants us to request events.
1106 */
request_events(void * send_info)1107 static void request_events(void *send_info)
1108 {
1109 struct ssif_info *ssif_info = send_info;
1110 unsigned long oflags, *flags;
1111
1112 if (!ssif_info->has_event_buffer)
1113 return;
1114
1115 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
1116 ssif_info->req_events = true;
1117 ipmi_ssif_unlock_cond(ssif_info, flags);
1118 }
1119
1120 /*
1121 * Upper layer is changing the flag saying whether we need to request
1122 * flags periodically or not.
1123 */
ssif_set_need_watch(void * send_info,unsigned int watch_mask)1124 static void ssif_set_need_watch(void *send_info, unsigned int watch_mask)
1125 {
1126 struct ssif_info *ssif_info = send_info;
1127 unsigned long oflags, *flags;
1128 long timeout = 0;
1129
1130 if (watch_mask & IPMI_WATCH_MASK_CHECK_MESSAGES)
1131 timeout = SSIF_WATCH_MSG_TIMEOUT;
1132 else if (watch_mask)
1133 timeout = SSIF_WATCH_WATCHDOG_TIMEOUT;
1134
1135 flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
1136 if (timeout != ssif_info->watch_timeout) {
1137 ssif_info->watch_timeout = timeout;
1138 if (ssif_info->watch_timeout)
1139 mod_timer(&ssif_info->watch_timer,
1140 jiffies + ssif_info->watch_timeout);
1141 }
1142 ipmi_ssif_unlock_cond(ssif_info, flags);
1143 }
1144
ssif_start_processing(void * send_info,struct ipmi_smi * intf)1145 static int ssif_start_processing(void *send_info,
1146 struct ipmi_smi *intf)
1147 {
1148 struct ssif_info *ssif_info = send_info;
1149
1150 ssif_info->intf = intf;
1151
1152 return 0;
1153 }
1154
1155 #define MAX_SSIF_BMCS 4
1156
1157 static unsigned short addr[MAX_SSIF_BMCS];
1158 static int num_addrs;
1159 module_param_array(addr, ushort, &num_addrs, 0);
1160 MODULE_PARM_DESC(addr, "The addresses to scan for IPMI BMCs on the SSIFs.");
1161
1162 static char *adapter_name[MAX_SSIF_BMCS];
1163 static int num_adapter_names;
1164 module_param_array(adapter_name, charp, &num_adapter_names, 0);
1165 MODULE_PARM_DESC(adapter_name, "The string name of the I2C device that has the BMC. By default all devices are scanned.");
1166
1167 static int slave_addrs[MAX_SSIF_BMCS];
1168 static int num_slave_addrs;
1169 module_param_array(slave_addrs, int, &num_slave_addrs, 0);
1170 MODULE_PARM_DESC(slave_addrs,
1171 "The default IPMB slave address for the controller.");
1172
1173 static bool alerts_broken;
1174 module_param(alerts_broken, bool, 0);
1175 MODULE_PARM_DESC(alerts_broken, "Don't enable alerts for the controller.");
1176
1177 /*
1178 * Bit 0 enables message debugging, bit 1 enables state debugging, and
1179 * bit 2 enables timing debugging. This is an array indexed by
1180 * interface number"
1181 */
1182 static int dbg[MAX_SSIF_BMCS];
1183 static int num_dbg;
1184 module_param_array(dbg, int, &num_dbg, 0);
1185 MODULE_PARM_DESC(dbg, "Turn on debugging.");
1186
1187 static bool ssif_dbg_probe;
1188 module_param_named(dbg_probe, ssif_dbg_probe, bool, 0);
1189 MODULE_PARM_DESC(dbg_probe, "Enable debugging of probing of adapters.");
1190
1191 static bool ssif_tryacpi = true;
1192 module_param_named(tryacpi, ssif_tryacpi, bool, 0);
1193 MODULE_PARM_DESC(tryacpi, "Setting this to zero will disable the default scan of the interfaces identified via ACPI");
1194
1195 static bool ssif_trydmi = true;
1196 module_param_named(trydmi, ssif_trydmi, bool, 0);
1197 MODULE_PARM_DESC(trydmi, "Setting this to zero will disable the default scan of the interfaces identified via DMI (SMBIOS)");
1198
1199 static DEFINE_MUTEX(ssif_infos_mutex);
1200 static LIST_HEAD(ssif_infos);
1201
1202 #define IPMI_SSIF_ATTR(name) \
1203 static ssize_t ipmi_##name##_show(struct device *dev, \
1204 struct device_attribute *attr, \
1205 char *buf) \
1206 { \
1207 struct ssif_info *ssif_info = dev_get_drvdata(dev); \
1208 \
1209 return sysfs_emit(buf, "%u\n", ssif_get_stat(ssif_info, name));\
1210 } \
1211 static DEVICE_ATTR(name, S_IRUGO, ipmi_##name##_show, NULL)
1212
ipmi_type_show(struct device * dev,struct device_attribute * attr,char * buf)1213 static ssize_t ipmi_type_show(struct device *dev,
1214 struct device_attribute *attr,
1215 char *buf)
1216 {
1217 return sysfs_emit(buf, "ssif\n");
1218 }
1219 static DEVICE_ATTR(type, S_IRUGO, ipmi_type_show, NULL);
1220
1221 IPMI_SSIF_ATTR(sent_messages);
1222 IPMI_SSIF_ATTR(sent_messages_parts);
1223 IPMI_SSIF_ATTR(send_retries);
1224 IPMI_SSIF_ATTR(send_errors);
1225 IPMI_SSIF_ATTR(received_messages);
1226 IPMI_SSIF_ATTR(received_message_parts);
1227 IPMI_SSIF_ATTR(receive_retries);
1228 IPMI_SSIF_ATTR(receive_errors);
1229 IPMI_SSIF_ATTR(flag_fetches);
1230 IPMI_SSIF_ATTR(hosed);
1231 IPMI_SSIF_ATTR(events);
1232 IPMI_SSIF_ATTR(watchdog_pretimeouts);
1233 IPMI_SSIF_ATTR(alerts);
1234
1235 static struct attribute *ipmi_ssif_dev_attrs[] = {
1236 &dev_attr_type.attr,
1237 &dev_attr_sent_messages.attr,
1238 &dev_attr_sent_messages_parts.attr,
1239 &dev_attr_send_retries.attr,
1240 &dev_attr_send_errors.attr,
1241 &dev_attr_received_messages.attr,
1242 &dev_attr_received_message_parts.attr,
1243 &dev_attr_receive_retries.attr,
1244 &dev_attr_receive_errors.attr,
1245 &dev_attr_flag_fetches.attr,
1246 &dev_attr_hosed.attr,
1247 &dev_attr_events.attr,
1248 &dev_attr_watchdog_pretimeouts.attr,
1249 &dev_attr_alerts.attr,
1250 NULL
1251 };
1252
1253 static const struct attribute_group ipmi_ssif_dev_attr_group = {
1254 .attrs = ipmi_ssif_dev_attrs,
1255 };
1256
shutdown_ssif(void * send_info)1257 static void shutdown_ssif(void *send_info)
1258 {
1259 struct ssif_info *ssif_info = send_info;
1260
1261 device_remove_group(&ssif_info->client->dev, &ipmi_ssif_dev_attr_group);
1262 dev_set_drvdata(&ssif_info->client->dev, NULL);
1263
1264 /* make sure the driver is not looking for flags any more. */
1265 while (ssif_info->ssif_state != SSIF_IDLE)
1266 schedule_timeout(1);
1267
1268 ssif_info->stopping = true;
1269 del_timer_sync(&ssif_info->watch_timer);
1270 del_timer_sync(&ssif_info->retry_timer);
1271 if (ssif_info->thread) {
1272 complete(&ssif_info->wake_thread);
1273 kthread_stop(ssif_info->thread);
1274 }
1275 }
1276
ssif_remove(struct i2c_client * client)1277 static void ssif_remove(struct i2c_client *client)
1278 {
1279 struct ssif_info *ssif_info = i2c_get_clientdata(client);
1280 struct ssif_addr_info *addr_info;
1281
1282 if (!ssif_info)
1283 return;
1284
1285 /*
1286 * After this point, we won't deliver anything asychronously
1287 * to the message handler. We can unregister ourself.
1288 */
1289 ipmi_unregister_smi(ssif_info->intf);
1290
1291 list_for_each_entry(addr_info, &ssif_infos, link) {
1292 if (addr_info->client == client) {
1293 addr_info->client = NULL;
1294 break;
1295 }
1296 }
1297
1298 kfree(ssif_info);
1299 }
1300
read_response(struct i2c_client * client,unsigned char * resp)1301 static int read_response(struct i2c_client *client, unsigned char *resp)
1302 {
1303 int ret = -ENODEV, retry_cnt = SSIF_RECV_RETRIES;
1304
1305 while (retry_cnt > 0) {
1306 ret = i2c_smbus_read_block_data(client, SSIF_IPMI_RESPONSE,
1307 resp);
1308 if (ret > 0)
1309 break;
1310 msleep(SSIF_MSG_MSEC);
1311 retry_cnt--;
1312 if (retry_cnt <= 0)
1313 break;
1314 }
1315
1316 return ret;
1317 }
1318
do_cmd(struct i2c_client * client,int len,unsigned char * msg,int * resp_len,unsigned char * resp)1319 static int do_cmd(struct i2c_client *client, int len, unsigned char *msg,
1320 int *resp_len, unsigned char *resp)
1321 {
1322 int retry_cnt;
1323 int ret;
1324
1325 retry_cnt = SSIF_SEND_RETRIES;
1326 retry1:
1327 ret = i2c_smbus_write_block_data(client, SSIF_IPMI_REQUEST, len, msg);
1328 if (ret) {
1329 retry_cnt--;
1330 if (retry_cnt > 0) {
1331 msleep(SSIF_REQ_RETRY_MSEC);
1332 goto retry1;
1333 }
1334 return -ENODEV;
1335 }
1336
1337 ret = read_response(client, resp);
1338 if (ret > 0) {
1339 /* Validate that the response is correct. */
1340 if (ret < 3 ||
1341 (resp[0] != (msg[0] | (1 << 2))) ||
1342 (resp[1] != msg[1]))
1343 ret = -EINVAL;
1344 else if (ret > IPMI_MAX_MSG_LENGTH) {
1345 ret = -E2BIG;
1346 } else {
1347 *resp_len = ret;
1348 ret = 0;
1349 }
1350 }
1351
1352 return ret;
1353 }
1354
ssif_detect(struct i2c_client * client,struct i2c_board_info * info)1355 static int ssif_detect(struct i2c_client *client, struct i2c_board_info *info)
1356 {
1357 unsigned char *resp;
1358 unsigned char msg[3];
1359 int rv;
1360 int len;
1361
1362 resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
1363 if (!resp)
1364 return -ENOMEM;
1365
1366 /* Do a Get Device ID command, since it is required. */
1367 msg[0] = IPMI_NETFN_APP_REQUEST << 2;
1368 msg[1] = IPMI_GET_DEVICE_ID_CMD;
1369 rv = do_cmd(client, 2, msg, &len, resp);
1370 if (rv)
1371 rv = -ENODEV;
1372 else
1373 strscpy(info->type, DEVICE_NAME, I2C_NAME_SIZE);
1374 kfree(resp);
1375 return rv;
1376 }
1377
strcmp_nospace(char * s1,char * s2)1378 static int strcmp_nospace(char *s1, char *s2)
1379 {
1380 while (*s1 && *s2) {
1381 while (isspace(*s1))
1382 s1++;
1383 while (isspace(*s2))
1384 s2++;
1385 if (*s1 > *s2)
1386 return 1;
1387 if (*s1 < *s2)
1388 return -1;
1389 s1++;
1390 s2++;
1391 }
1392 return 0;
1393 }
1394
ssif_info_find(unsigned short addr,char * adapter_name,bool match_null_name)1395 static struct ssif_addr_info *ssif_info_find(unsigned short addr,
1396 char *adapter_name,
1397 bool match_null_name)
1398 {
1399 struct ssif_addr_info *info, *found = NULL;
1400
1401 restart:
1402 list_for_each_entry(info, &ssif_infos, link) {
1403 if (info->binfo.addr == addr) {
1404 if (info->addr_src == SI_SMBIOS)
1405 info->adapter_name = kstrdup(adapter_name,
1406 GFP_KERNEL);
1407
1408 if (info->adapter_name || adapter_name) {
1409 if (!info->adapter_name != !adapter_name) {
1410 /* One is NULL and one is not */
1411 continue;
1412 }
1413 if (adapter_name &&
1414 strcmp_nospace(info->adapter_name,
1415 adapter_name))
1416 /* Names do not match */
1417 continue;
1418 }
1419 found = info;
1420 break;
1421 }
1422 }
1423
1424 if (!found && match_null_name) {
1425 /* Try to get an exact match first, then try with a NULL name */
1426 adapter_name = NULL;
1427 match_null_name = false;
1428 goto restart;
1429 }
1430
1431 return found;
1432 }
1433
check_acpi(struct ssif_info * ssif_info,struct device * dev)1434 static bool check_acpi(struct ssif_info *ssif_info, struct device *dev)
1435 {
1436 #ifdef CONFIG_ACPI
1437 acpi_handle acpi_handle;
1438
1439 acpi_handle = ACPI_HANDLE(dev);
1440 if (acpi_handle) {
1441 ssif_info->addr_source = SI_ACPI;
1442 ssif_info->addr_info.acpi_info.acpi_handle = acpi_handle;
1443 request_module("acpi_ipmi");
1444 return true;
1445 }
1446 #endif
1447 return false;
1448 }
1449
find_slave_address(struct i2c_client * client,int slave_addr)1450 static int find_slave_address(struct i2c_client *client, int slave_addr)
1451 {
1452 #ifdef CONFIG_IPMI_DMI_DECODE
1453 if (!slave_addr)
1454 slave_addr = ipmi_dmi_get_slave_addr(
1455 SI_TYPE_INVALID,
1456 i2c_adapter_id(client->adapter),
1457 client->addr);
1458 #endif
1459
1460 return slave_addr;
1461 }
1462
start_multipart_test(struct i2c_client * client,unsigned char * msg,bool do_middle)1463 static int start_multipart_test(struct i2c_client *client,
1464 unsigned char *msg, bool do_middle)
1465 {
1466 int retry_cnt = SSIF_SEND_RETRIES, ret;
1467
1468 retry_write:
1469 ret = i2c_smbus_write_block_data(client,
1470 SSIF_IPMI_MULTI_PART_REQUEST_START,
1471 32, msg);
1472 if (ret) {
1473 retry_cnt--;
1474 if (retry_cnt > 0) {
1475 msleep(SSIF_REQ_RETRY_MSEC);
1476 goto retry_write;
1477 }
1478 dev_err(&client->dev, "Could not write multi-part start, though the BMC said it could handle it. Just limit sends to one part.\n");
1479 return ret;
1480 }
1481
1482 if (!do_middle)
1483 return 0;
1484
1485 ret = i2c_smbus_write_block_data(client,
1486 SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE,
1487 32, msg + 32);
1488 if (ret) {
1489 dev_err(&client->dev, "Could not write multi-part middle, though the BMC said it could handle it. Just limit sends to one part.\n");
1490 return ret;
1491 }
1492
1493 return 0;
1494 }
1495
test_multipart_messages(struct i2c_client * client,struct ssif_info * ssif_info,unsigned char * resp)1496 static void test_multipart_messages(struct i2c_client *client,
1497 struct ssif_info *ssif_info,
1498 unsigned char *resp)
1499 {
1500 unsigned char msg[65];
1501 int ret;
1502 bool do_middle;
1503
1504 if (ssif_info->max_xmit_msg_size <= 32)
1505 return;
1506
1507 do_middle = ssif_info->max_xmit_msg_size > 63;
1508
1509 memset(msg, 0, sizeof(msg));
1510 msg[0] = IPMI_NETFN_APP_REQUEST << 2;
1511 msg[1] = IPMI_GET_DEVICE_ID_CMD;
1512
1513 /*
1514 * The specification is all messed up dealing with sending
1515 * multi-part messages. Per what the specification says, it
1516 * is impossible to send a message that is a multiple of 32
1517 * bytes, except for 32 itself. It talks about a "start"
1518 * transaction (cmd=6) that must be 32 bytes, "middle"
1519 * transaction (cmd=7) that must be 32 bytes, and an "end"
1520 * transaction. The "end" transaction is shown as cmd=7 in
1521 * the text, but if that's the case there is no way to
1522 * differentiate between a middle and end part except the
1523 * length being less than 32. But there is a table at the far
1524 * end of the section (that I had never noticed until someone
1525 * pointed it out to me) that mentions it as cmd=8.
1526 *
1527 * After some thought, I think the example is wrong and the
1528 * end transaction should be cmd=8. But some systems don't
1529 * implement cmd=8, they use a zero-length end transaction,
1530 * even though that violates the SMBus specification.
1531 *
1532 * So, to work around this, this code tests if cmd=8 works.
1533 * If it does, then we use that. If not, it tests zero-
1534 * byte end transactions. If that works, good. If not,
1535 * we only allow 63-byte transactions max.
1536 */
1537
1538 ret = start_multipart_test(client, msg, do_middle);
1539 if (ret)
1540 goto out_no_multi_part;
1541
1542 ret = i2c_smbus_write_block_data(client,
1543 SSIF_IPMI_MULTI_PART_REQUEST_END,
1544 1, msg + 64);
1545
1546 if (!ret)
1547 ret = read_response(client, resp);
1548
1549 if (ret > 0) {
1550 /* End transactions work, we are good. */
1551 ssif_info->cmd8_works = true;
1552 return;
1553 }
1554
1555 ret = start_multipart_test(client, msg, do_middle);
1556 if (ret) {
1557 dev_err(&client->dev, "Second multipart test failed.\n");
1558 goto out_no_multi_part;
1559 }
1560
1561 ret = i2c_smbus_write_block_data(client,
1562 SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE,
1563 0, msg + 64);
1564 if (!ret)
1565 ret = read_response(client, resp);
1566 if (ret > 0)
1567 /* Zero-size end parts work, use those. */
1568 return;
1569
1570 /* Limit to 63 bytes and use a short middle command to mark the end. */
1571 if (ssif_info->max_xmit_msg_size > 63)
1572 ssif_info->max_xmit_msg_size = 63;
1573 return;
1574
1575 out_no_multi_part:
1576 ssif_info->max_xmit_msg_size = 32;
1577 return;
1578 }
1579
1580 /*
1581 * Global enables we care about.
1582 */
1583 #define GLOBAL_ENABLES_MASK (IPMI_BMC_EVT_MSG_BUFF | IPMI_BMC_RCV_MSG_INTR | \
1584 IPMI_BMC_EVT_MSG_INTR)
1585
ssif_remove_dup(struct i2c_client * client)1586 static void ssif_remove_dup(struct i2c_client *client)
1587 {
1588 struct ssif_info *ssif_info = i2c_get_clientdata(client);
1589
1590 ipmi_unregister_smi(ssif_info->intf);
1591 kfree(ssif_info);
1592 }
1593
ssif_add_infos(struct i2c_client * client)1594 static int ssif_add_infos(struct i2c_client *client)
1595 {
1596 struct ssif_addr_info *info;
1597
1598 info = kzalloc(sizeof(*info), GFP_KERNEL);
1599 if (!info)
1600 return -ENOMEM;
1601 info->addr_src = SI_ACPI;
1602 info->client = client;
1603 info->adapter_name = kstrdup(client->adapter->name, GFP_KERNEL);
1604 info->binfo.addr = client->addr;
1605 list_add_tail(&info->link, &ssif_infos);
1606 return 0;
1607 }
1608
1609 /*
1610 * Prefer ACPI over SMBIOS, if both are available.
1611 * So if we get an ACPI interface and have already registered a SMBIOS
1612 * interface at the same address, remove the SMBIOS and add the ACPI one.
1613 */
ssif_check_and_remove(struct i2c_client * client,struct ssif_info * ssif_info)1614 static int ssif_check_and_remove(struct i2c_client *client,
1615 struct ssif_info *ssif_info)
1616 {
1617 struct ssif_addr_info *info;
1618
1619 list_for_each_entry(info, &ssif_infos, link) {
1620 if (!info->client)
1621 return 0;
1622 if (!strcmp(info->adapter_name, client->adapter->name) &&
1623 info->binfo.addr == client->addr) {
1624 if (info->addr_src == SI_ACPI)
1625 return -EEXIST;
1626
1627 if (ssif_info->addr_source == SI_ACPI &&
1628 info->addr_src == SI_SMBIOS) {
1629 dev_info(&client->dev,
1630 "Removing %s-specified SSIF interface in favor of ACPI\n",
1631 ipmi_addr_src_to_str(info->addr_src));
1632 ssif_remove_dup(info->client);
1633 return 0;
1634 }
1635 }
1636 }
1637 return 0;
1638 }
1639
ssif_probe(struct i2c_client * client)1640 static int ssif_probe(struct i2c_client *client)
1641 {
1642 unsigned char msg[3];
1643 unsigned char *resp;
1644 struct ssif_info *ssif_info;
1645 int rv = 0;
1646 int len = 0;
1647 int i;
1648 u8 slave_addr = 0;
1649 struct ssif_addr_info *addr_info = NULL;
1650
1651 mutex_lock(&ssif_infos_mutex);
1652 resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
1653 if (!resp) {
1654 mutex_unlock(&ssif_infos_mutex);
1655 return -ENOMEM;
1656 }
1657
1658 ssif_info = kzalloc(sizeof(*ssif_info), GFP_KERNEL);
1659 if (!ssif_info) {
1660 kfree(resp);
1661 mutex_unlock(&ssif_infos_mutex);
1662 return -ENOMEM;
1663 }
1664
1665 if (!check_acpi(ssif_info, &client->dev)) {
1666 addr_info = ssif_info_find(client->addr, client->adapter->name,
1667 true);
1668 if (!addr_info) {
1669 /* Must have come in through sysfs. */
1670 ssif_info->addr_source = SI_HOTMOD;
1671 } else {
1672 ssif_info->addr_source = addr_info->addr_src;
1673 ssif_info->ssif_debug = addr_info->debug;
1674 ssif_info->addr_info = addr_info->addr_info;
1675 addr_info->client = client;
1676 slave_addr = addr_info->slave_addr;
1677 }
1678 }
1679
1680 ssif_info->client = client;
1681 i2c_set_clientdata(client, ssif_info);
1682
1683 rv = ssif_check_and_remove(client, ssif_info);
1684 /* If rv is 0 and addr source is not SI_ACPI, continue probing */
1685 if (!rv && ssif_info->addr_source == SI_ACPI) {
1686 rv = ssif_add_infos(client);
1687 if (rv) {
1688 dev_err(&client->dev, "Out of memory!, exiting ..\n");
1689 goto out;
1690 }
1691 } else if (rv) {
1692 dev_err(&client->dev, "Not probing, Interface already present\n");
1693 goto out;
1694 }
1695
1696 slave_addr = find_slave_address(client, slave_addr);
1697
1698 dev_info(&client->dev,
1699 "Trying %s-specified SSIF interface at i2c address 0x%x, adapter %s, slave address 0x%x\n",
1700 ipmi_addr_src_to_str(ssif_info->addr_source),
1701 client->addr, client->adapter->name, slave_addr);
1702
1703 /* Now check for system interface capabilities */
1704 msg[0] = IPMI_NETFN_APP_REQUEST << 2;
1705 msg[1] = IPMI_GET_SYSTEM_INTERFACE_CAPABILITIES_CMD;
1706 msg[2] = 0; /* SSIF */
1707 rv = do_cmd(client, 3, msg, &len, resp);
1708 if (!rv && (len >= 3) && (resp[2] == 0)) {
1709 if (len < 7) {
1710 if (ssif_dbg_probe)
1711 dev_dbg(&ssif_info->client->dev,
1712 "SSIF info too short: %d\n", len);
1713 goto no_support;
1714 }
1715
1716 /* Got a good SSIF response, handle it. */
1717 ssif_info->max_xmit_msg_size = resp[5];
1718 ssif_info->max_recv_msg_size = resp[6];
1719 ssif_info->multi_support = (resp[4] >> 6) & 0x3;
1720 ssif_info->supports_pec = (resp[4] >> 3) & 0x1;
1721
1722 /* Sanitize the data */
1723 switch (ssif_info->multi_support) {
1724 case SSIF_NO_MULTI:
1725 if (ssif_info->max_xmit_msg_size > 32)
1726 ssif_info->max_xmit_msg_size = 32;
1727 if (ssif_info->max_recv_msg_size > 32)
1728 ssif_info->max_recv_msg_size = 32;
1729 break;
1730
1731 case SSIF_MULTI_2_PART:
1732 if (ssif_info->max_xmit_msg_size > 63)
1733 ssif_info->max_xmit_msg_size = 63;
1734 if (ssif_info->max_recv_msg_size > 62)
1735 ssif_info->max_recv_msg_size = 62;
1736 break;
1737
1738 case SSIF_MULTI_n_PART:
1739 /* We take whatever size given, but do some testing. */
1740 break;
1741
1742 default:
1743 /* Data is not sane, just give up. */
1744 goto no_support;
1745 }
1746 } else {
1747 no_support:
1748 /* Assume no multi-part or PEC support */
1749 dev_info(&ssif_info->client->dev,
1750 "Error fetching SSIF: %d %d %2.2x, your system probably doesn't support this command so using defaults\n",
1751 rv, len, resp[2]);
1752
1753 ssif_info->max_xmit_msg_size = 32;
1754 ssif_info->max_recv_msg_size = 32;
1755 ssif_info->multi_support = SSIF_NO_MULTI;
1756 ssif_info->supports_pec = 0;
1757 }
1758
1759 test_multipart_messages(client, ssif_info, resp);
1760
1761 /* Make sure the NMI timeout is cleared. */
1762 msg[0] = IPMI_NETFN_APP_REQUEST << 2;
1763 msg[1] = IPMI_CLEAR_MSG_FLAGS_CMD;
1764 msg[2] = WDT_PRE_TIMEOUT_INT;
1765 rv = do_cmd(client, 3, msg, &len, resp);
1766 if (rv || (len < 3) || (resp[2] != 0))
1767 dev_warn(&ssif_info->client->dev,
1768 "Unable to clear message flags: %d %d %2.2x\n",
1769 rv, len, resp[2]);
1770
1771 /* Attempt to enable the event buffer. */
1772 msg[0] = IPMI_NETFN_APP_REQUEST << 2;
1773 msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD;
1774 rv = do_cmd(client, 2, msg, &len, resp);
1775 if (rv || (len < 4) || (resp[2] != 0)) {
1776 dev_warn(&ssif_info->client->dev,
1777 "Error getting global enables: %d %d %2.2x\n",
1778 rv, len, resp[2]);
1779 rv = 0; /* Not fatal */
1780 goto found;
1781 }
1782
1783 ssif_info->global_enables = resp[3];
1784
1785 if (resp[3] & IPMI_BMC_EVT_MSG_BUFF) {
1786 ssif_info->has_event_buffer = true;
1787 /* buffer is already enabled, nothing to do. */
1788 goto found;
1789 }
1790
1791 msg[0] = IPMI_NETFN_APP_REQUEST << 2;
1792 msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD;
1793 msg[2] = ssif_info->global_enables | IPMI_BMC_EVT_MSG_BUFF;
1794 rv = do_cmd(client, 3, msg, &len, resp);
1795 if (rv || (len < 2)) {
1796 dev_warn(&ssif_info->client->dev,
1797 "Error setting global enables: %d %d %2.2x\n",
1798 rv, len, resp[2]);
1799 rv = 0; /* Not fatal */
1800 goto found;
1801 }
1802
1803 if (resp[2] == 0) {
1804 /* A successful return means the event buffer is supported. */
1805 ssif_info->has_event_buffer = true;
1806 ssif_info->global_enables |= IPMI_BMC_EVT_MSG_BUFF;
1807 }
1808
1809 /* Some systems don't behave well if you enable alerts. */
1810 if (alerts_broken)
1811 goto found;
1812
1813 msg[0] = IPMI_NETFN_APP_REQUEST << 2;
1814 msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD;
1815 msg[2] = ssif_info->global_enables | IPMI_BMC_RCV_MSG_INTR;
1816 rv = do_cmd(client, 3, msg, &len, resp);
1817 if (rv || (len < 2)) {
1818 dev_warn(&ssif_info->client->dev,
1819 "Error setting global enables: %d %d %2.2x\n",
1820 rv, len, resp[2]);
1821 rv = 0; /* Not fatal */
1822 goto found;
1823 }
1824
1825 if (resp[2] == 0) {
1826 /* A successful return means the alert is supported. */
1827 ssif_info->supports_alert = true;
1828 ssif_info->global_enables |= IPMI_BMC_RCV_MSG_INTR;
1829 }
1830
1831 found:
1832 if (ssif_dbg_probe) {
1833 dev_dbg(&ssif_info->client->dev,
1834 "%s: i2c_probe found device at i2c address %x\n",
1835 __func__, client->addr);
1836 }
1837
1838 spin_lock_init(&ssif_info->lock);
1839 ssif_info->ssif_state = SSIF_IDLE;
1840 timer_setup(&ssif_info->retry_timer, retry_timeout, 0);
1841 timer_setup(&ssif_info->watch_timer, watch_timeout, 0);
1842
1843 for (i = 0; i < SSIF_NUM_STATS; i++)
1844 atomic_set(&ssif_info->stats[i], 0);
1845
1846 if (ssif_info->supports_pec)
1847 ssif_info->client->flags |= I2C_CLIENT_PEC;
1848
1849 ssif_info->handlers.owner = THIS_MODULE;
1850 ssif_info->handlers.start_processing = ssif_start_processing;
1851 ssif_info->handlers.shutdown = shutdown_ssif;
1852 ssif_info->handlers.get_smi_info = get_smi_info;
1853 ssif_info->handlers.sender = sender;
1854 ssif_info->handlers.request_events = request_events;
1855 ssif_info->handlers.set_need_watch = ssif_set_need_watch;
1856
1857 {
1858 unsigned int thread_num;
1859
1860 thread_num = ((i2c_adapter_id(ssif_info->client->adapter)
1861 << 8) |
1862 ssif_info->client->addr);
1863 init_completion(&ssif_info->wake_thread);
1864 ssif_info->thread = kthread_run(ipmi_ssif_thread, ssif_info,
1865 "kssif%4.4x", thread_num);
1866 if (IS_ERR(ssif_info->thread)) {
1867 rv = PTR_ERR(ssif_info->thread);
1868 dev_notice(&ssif_info->client->dev,
1869 "Could not start kernel thread: error %d\n",
1870 rv);
1871 goto out;
1872 }
1873 }
1874
1875 dev_set_drvdata(&ssif_info->client->dev, ssif_info);
1876 rv = device_add_group(&ssif_info->client->dev,
1877 &ipmi_ssif_dev_attr_group);
1878 if (rv) {
1879 dev_err(&ssif_info->client->dev,
1880 "Unable to add device attributes: error %d\n",
1881 rv);
1882 goto out;
1883 }
1884
1885 rv = ipmi_register_smi(&ssif_info->handlers,
1886 ssif_info,
1887 &ssif_info->client->dev,
1888 slave_addr);
1889 if (rv) {
1890 dev_err(&ssif_info->client->dev,
1891 "Unable to register device: error %d\n", rv);
1892 goto out_remove_attr;
1893 }
1894
1895 out:
1896 if (rv) {
1897 if (addr_info)
1898 addr_info->client = NULL;
1899
1900 dev_err(&ssif_info->client->dev,
1901 "Unable to start IPMI SSIF: %d\n", rv);
1902 i2c_set_clientdata(client, NULL);
1903 kfree(ssif_info);
1904 }
1905 kfree(resp);
1906 mutex_unlock(&ssif_infos_mutex);
1907 return rv;
1908
1909 out_remove_attr:
1910 device_remove_group(&ssif_info->client->dev, &ipmi_ssif_dev_attr_group);
1911 dev_set_drvdata(&ssif_info->client->dev, NULL);
1912 goto out;
1913 }
1914
new_ssif_client(int addr,char * adapter_name,int debug,int slave_addr,enum ipmi_addr_src addr_src,struct device * dev)1915 static int new_ssif_client(int addr, char *adapter_name,
1916 int debug, int slave_addr,
1917 enum ipmi_addr_src addr_src,
1918 struct device *dev)
1919 {
1920 struct ssif_addr_info *addr_info;
1921 int rv = 0;
1922
1923 mutex_lock(&ssif_infos_mutex);
1924 if (ssif_info_find(addr, adapter_name, false)) {
1925 rv = -EEXIST;
1926 goto out_unlock;
1927 }
1928
1929 addr_info = kzalloc(sizeof(*addr_info), GFP_KERNEL);
1930 if (!addr_info) {
1931 rv = -ENOMEM;
1932 goto out_unlock;
1933 }
1934
1935 if (adapter_name) {
1936 addr_info->adapter_name = kstrdup(adapter_name, GFP_KERNEL);
1937 if (!addr_info->adapter_name) {
1938 kfree(addr_info);
1939 rv = -ENOMEM;
1940 goto out_unlock;
1941 }
1942 }
1943
1944 strncpy(addr_info->binfo.type, DEVICE_NAME,
1945 sizeof(addr_info->binfo.type));
1946 addr_info->binfo.addr = addr;
1947 addr_info->binfo.platform_data = addr_info;
1948 addr_info->debug = debug;
1949 addr_info->slave_addr = slave_addr;
1950 addr_info->addr_src = addr_src;
1951 addr_info->dev = dev;
1952
1953 if (dev)
1954 dev_set_drvdata(dev, addr_info);
1955
1956 list_add_tail(&addr_info->link, &ssif_infos);
1957
1958 /* Address list will get it */
1959
1960 out_unlock:
1961 mutex_unlock(&ssif_infos_mutex);
1962 return rv;
1963 }
1964
free_ssif_clients(void)1965 static void free_ssif_clients(void)
1966 {
1967 struct ssif_addr_info *info, *tmp;
1968
1969 mutex_lock(&ssif_infos_mutex);
1970 list_for_each_entry_safe(info, tmp, &ssif_infos, link) {
1971 list_del(&info->link);
1972 kfree(info->adapter_name);
1973 kfree(info);
1974 }
1975 mutex_unlock(&ssif_infos_mutex);
1976 }
1977
ssif_address_list(void)1978 static unsigned short *ssif_address_list(void)
1979 {
1980 struct ssif_addr_info *info;
1981 unsigned int count = 0, i = 0;
1982 unsigned short *address_list;
1983
1984 list_for_each_entry(info, &ssif_infos, link)
1985 count++;
1986
1987 address_list = kcalloc(count + 1, sizeof(*address_list),
1988 GFP_KERNEL);
1989 if (!address_list)
1990 return NULL;
1991
1992 list_for_each_entry(info, &ssif_infos, link) {
1993 unsigned short addr = info->binfo.addr;
1994 int j;
1995
1996 for (j = 0; j < i; j++) {
1997 if (address_list[j] == addr)
1998 /* Found a dup. */
1999 break;
2000 }
2001 if (j == i) /* Didn't find it in the list. */
2002 address_list[i++] = addr;
2003 }
2004 address_list[i] = I2C_CLIENT_END;
2005
2006 return address_list;
2007 }
2008
2009 #ifdef CONFIG_ACPI
2010 static const struct acpi_device_id ssif_acpi_match[] = {
2011 { "IPI0001", 0 },
2012 { },
2013 };
2014 MODULE_DEVICE_TABLE(acpi, ssif_acpi_match);
2015 #endif
2016
2017 #ifdef CONFIG_DMI
dmi_ipmi_probe(struct platform_device * pdev)2018 static int dmi_ipmi_probe(struct platform_device *pdev)
2019 {
2020 u8 slave_addr = 0;
2021 u16 i2c_addr;
2022 int rv;
2023
2024 if (!ssif_trydmi)
2025 return -ENODEV;
2026
2027 rv = device_property_read_u16(&pdev->dev, "i2c-addr", &i2c_addr);
2028 if (rv) {
2029 dev_warn(&pdev->dev, "No i2c-addr property\n");
2030 return -ENODEV;
2031 }
2032
2033 rv = device_property_read_u8(&pdev->dev, "slave-addr", &slave_addr);
2034 if (rv)
2035 slave_addr = 0x20;
2036
2037 return new_ssif_client(i2c_addr, NULL, 0,
2038 slave_addr, SI_SMBIOS, &pdev->dev);
2039 }
2040 #else
dmi_ipmi_probe(struct platform_device * pdev)2041 static int dmi_ipmi_probe(struct platform_device *pdev)
2042 {
2043 return -ENODEV;
2044 }
2045 #endif
2046
2047 static const struct i2c_device_id ssif_id[] = {
2048 { DEVICE_NAME, 0 },
2049 { }
2050 };
2051 MODULE_DEVICE_TABLE(i2c, ssif_id);
2052
2053 static struct i2c_driver ssif_i2c_driver = {
2054 .class = I2C_CLASS_HWMON,
2055 .driver = {
2056 .name = DEVICE_NAME
2057 },
2058 .probe_new = ssif_probe,
2059 .remove = ssif_remove,
2060 .alert = ssif_alert,
2061 .id_table = ssif_id,
2062 .detect = ssif_detect
2063 };
2064
ssif_platform_probe(struct platform_device * dev)2065 static int ssif_platform_probe(struct platform_device *dev)
2066 {
2067 return dmi_ipmi_probe(dev);
2068 }
2069
ssif_platform_remove(struct platform_device * dev)2070 static int ssif_platform_remove(struct platform_device *dev)
2071 {
2072 struct ssif_addr_info *addr_info = dev_get_drvdata(&dev->dev);
2073
2074 if (!addr_info)
2075 return 0;
2076
2077 mutex_lock(&ssif_infos_mutex);
2078 list_del(&addr_info->link);
2079 kfree(addr_info);
2080 mutex_unlock(&ssif_infos_mutex);
2081 return 0;
2082 }
2083
2084 static const struct platform_device_id ssif_plat_ids[] = {
2085 { "dmi-ipmi-ssif", 0 },
2086 { }
2087 };
2088
2089 static struct platform_driver ipmi_driver = {
2090 .driver = {
2091 .name = DEVICE_NAME,
2092 },
2093 .probe = ssif_platform_probe,
2094 .remove = ssif_platform_remove,
2095 .id_table = ssif_plat_ids
2096 };
2097
init_ipmi_ssif(void)2098 static int __init init_ipmi_ssif(void)
2099 {
2100 int i;
2101 int rv;
2102
2103 if (initialized)
2104 return 0;
2105
2106 pr_info("IPMI SSIF Interface driver\n");
2107
2108 /* build list for i2c from addr list */
2109 for (i = 0; i < num_addrs; i++) {
2110 rv = new_ssif_client(addr[i], adapter_name[i],
2111 dbg[i], slave_addrs[i],
2112 SI_HARDCODED, NULL);
2113 if (rv)
2114 pr_err("Couldn't add hardcoded device at addr 0x%x\n",
2115 addr[i]);
2116 }
2117
2118 if (ssif_tryacpi)
2119 ssif_i2c_driver.driver.acpi_match_table =
2120 ACPI_PTR(ssif_acpi_match);
2121
2122 if (ssif_trydmi) {
2123 rv = platform_driver_register(&ipmi_driver);
2124 if (rv)
2125 pr_err("Unable to register driver: %d\n", rv);
2126 else
2127 platform_registered = true;
2128 }
2129
2130 ssif_i2c_driver.address_list = ssif_address_list();
2131
2132 rv = i2c_add_driver(&ssif_i2c_driver);
2133 if (!rv)
2134 initialized = true;
2135
2136 return rv;
2137 }
2138 module_init(init_ipmi_ssif);
2139
cleanup_ipmi_ssif(void)2140 static void __exit cleanup_ipmi_ssif(void)
2141 {
2142 if (!initialized)
2143 return;
2144
2145 initialized = false;
2146
2147 i2c_del_driver(&ssif_i2c_driver);
2148
2149 kfree(ssif_i2c_driver.address_list);
2150
2151 if (ssif_trydmi && platform_registered)
2152 platform_driver_unregister(&ipmi_driver);
2153
2154 free_ssif_clients();
2155 }
2156 module_exit(cleanup_ipmi_ssif);
2157
2158 MODULE_ALIAS("platform:dmi-ipmi-ssif");
2159 MODULE_AUTHOR("Todd C Davis <todd.c.davis@intel.com>, Corey Minyard <minyard@acm.org>");
2160 MODULE_DESCRIPTION("IPMI driver for management controllers on a SMBus");
2161 MODULE_LICENSE("GPL");
2162