1
2 /*
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2 of the License, or
6 * (at your option) any later version.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
16 *
17 * Copyright (C) IBM Corporation, 2004
18 *
19 * Author: Max Asb�ck <amax@us.ibm.com>
20 *
21 */
22
23 #include <linux/sched.h>
24 #include "ibmasm.h"
25 #include "dot_command.h"
26
27 /*
28 * Reverse Heartbeat, i.e. heartbeats sent from the driver to the
29 * service processor.
30 * These heartbeats are initiated by user level programs.
31 */
32
33 /* the reverse heartbeat dot command */
34 #pragma pack(1)
35 static struct {
36 struct dot_command_header header;
37 unsigned char command[3];
38 } rhb_dot_cmd = {
39 .header = {
40 .type = sp_read,
41 .command_size = 3,
42 .data_size = 0,
43 .status = 0
44 },
45 .command = { 4, 3, 6 }
46 };
47 #pragma pack()
48
ibmasm_init_reverse_heartbeat(struct service_processor * sp,struct reverse_heartbeat * rhb)49 void ibmasm_init_reverse_heartbeat(struct service_processor *sp, struct reverse_heartbeat *rhb)
50 {
51 init_waitqueue_head(&rhb->wait);
52 rhb->stopped = 0;
53 }
54
55 /**
56 * start_reverse_heartbeat
57 * Loop forever, sending a reverse heartbeat dot command to the service
58 * processor, then sleeping. The loop comes to an end if the service
59 * processor fails to respond 3 times or we were interrupted.
60 */
ibmasm_start_reverse_heartbeat(struct service_processor * sp,struct reverse_heartbeat * rhb)61 int ibmasm_start_reverse_heartbeat(struct service_processor *sp, struct reverse_heartbeat *rhb)
62 {
63 struct command *cmd;
64 int times_failed = 0;
65 int result = 1;
66
67 cmd = ibmasm_new_command(sp, sizeof rhb_dot_cmd);
68 if (!cmd)
69 return -ENOMEM;
70
71 while (times_failed < 3) {
72 memcpy(cmd->buffer, (void *)&rhb_dot_cmd, sizeof rhb_dot_cmd);
73 cmd->status = IBMASM_CMD_PENDING;
74 ibmasm_exec_command(sp, cmd);
75 ibmasm_wait_for_response(cmd, IBMASM_CMD_TIMEOUT_NORMAL);
76
77 if (cmd->status != IBMASM_CMD_COMPLETE)
78 times_failed++;
79
80 wait_event_interruptible_timeout(rhb->wait,
81 rhb->stopped,
82 REVERSE_HEARTBEAT_TIMEOUT * HZ);
83
84 if (signal_pending(current) || rhb->stopped) {
85 result = -EINTR;
86 break;
87 }
88 }
89 command_put(cmd);
90 rhb->stopped = 0;
91
92 return result;
93 }
94
ibmasm_stop_reverse_heartbeat(struct reverse_heartbeat * rhb)95 void ibmasm_stop_reverse_heartbeat(struct reverse_heartbeat *rhb)
96 {
97 rhb->stopped = 1;
98 wake_up_interruptible(&rhb->wait);
99 }
100