W1: w1_int.c use first available master number
[linux-2.6.git] / drivers / w1 / w1_netlink.c
1 /*
2  * w1_netlink.c
3  *
4  * Copyright (c) 2003 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
5  *
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20  */
21
22 #include <linux/skbuff.h>
23 #include <linux/netlink.h>
24 #include <linux/connector.h>
25
26 #include "w1.h"
27 #include "w1_log.h"
28 #include "w1_netlink.h"
29
30 #if defined(CONFIG_W1_CON) && (defined(CONFIG_CONNECTOR) || (defined(CONFIG_CONNECTOR_MODULE) && defined(CONFIG_W1_MODULE)))
31 void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
32 {
33         char buf[sizeof(struct cn_msg) + sizeof(struct w1_netlink_msg)];
34         struct cn_msg *m = (struct cn_msg *)buf;
35         struct w1_netlink_msg *w = (struct w1_netlink_msg *)(m+1);
36
37         memset(buf, 0, sizeof(buf));
38
39         m->id.idx = CN_W1_IDX;
40         m->id.val = CN_W1_VAL;
41
42         m->seq = dev->seq++;
43         m->len = sizeof(struct w1_netlink_msg);
44
45         memcpy(w, msg, sizeof(struct w1_netlink_msg));
46
47         cn_netlink_send(m, 0, GFP_KERNEL);
48 }
49
50 static int w1_process_command_master(struct w1_master *dev, struct cn_msg *msg,
51                 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
52 {
53         dev_dbg(&dev->dev, "%s: %s: cmd=%02x, len=%u.\n",
54                 __func__, dev->name, cmd->cmd, cmd->len);
55
56         if (cmd->cmd != W1_CMD_SEARCH && cmd->cmd != W1_CMD_ALARM_SEARCH)
57                 return -EINVAL;
58
59         w1_search_process(dev, (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH);
60         return 0;
61 }
62
63 static int w1_send_read_reply(struct w1_slave *sl, struct cn_msg *msg,
64                 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
65 {
66         void *data;
67         struct w1_netlink_msg *h;
68         struct w1_netlink_cmd *c;
69         struct cn_msg *cm;
70         int err;
71
72         data = kzalloc(sizeof(struct cn_msg) +
73                         sizeof(struct w1_netlink_msg) +
74                         sizeof(struct w1_netlink_cmd) +
75                         cmd->len, GFP_KERNEL);
76         if (!data)
77                 return -ENOMEM;
78
79         cm = (struct cn_msg *)(data);
80         h = (struct w1_netlink_msg *)(cm + 1);
81         c = (struct w1_netlink_cmd *)(h + 1);
82
83         memcpy(cm, msg, sizeof(struct cn_msg));
84         memcpy(h, hdr, sizeof(struct w1_netlink_msg));
85         memcpy(c, cmd, sizeof(struct w1_netlink_cmd));
86
87         cm->ack = msg->seq+1;
88         cm->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd) + cmd->len;
89
90         h->len = sizeof(struct w1_netlink_cmd) + cmd->len;
91
92         memcpy(c->data, cmd->data, c->len);
93
94         err = cn_netlink_send(cm, 0, GFP_KERNEL);
95
96         kfree(data);
97
98         return err;
99 }
100
101 static int w1_process_command_slave(struct w1_slave *sl, struct cn_msg *msg,
102                 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
103 {
104         int err = 0;
105
106         dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n",
107                 __func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id, sl->reg_num.crc,
108                 cmd->cmd, cmd->len);
109
110         switch (cmd->cmd) {
111                 case W1_CMD_READ:
112                         w1_read_block(sl->master, cmd->data, cmd->len);
113                         w1_send_read_reply(sl, msg, hdr, cmd);
114                         break;
115                 case W1_CMD_WRITE:
116                         w1_write_block(sl->master, cmd->data, cmd->len);
117                         break;
118                 case W1_CMD_SEARCH:
119                 case W1_CMD_ALARM_SEARCH:
120                         w1_search_process(sl->master,
121                                         (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH);
122                         break;
123                 default:
124                         err = -1;
125                         break;
126         }
127
128         return err;
129 }
130
131 static void w1_cn_callback(void *data)
132 {
133         struct cn_msg *msg = data;
134         struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1);
135         struct w1_netlink_cmd *cmd;
136         struct w1_slave *sl;
137         struct w1_master *dev;
138         int err = 0;
139
140         while (msg->len && !err) {
141                 struct w1_reg_num id;
142                 u16 mlen = m->len;
143                 u8 *cmd_data = m->data;
144
145                 dev = NULL;
146                 sl = NULL;
147
148                 memcpy(&id, m->id.id, sizeof(id));
149 #if 0
150                 printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n",
151                                 __func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len);
152 #endif
153                 if (m->len + sizeof(struct w1_netlink_msg) > msg->len) {
154                         err = -E2BIG;
155                         break;
156                 }
157
158                 if (!mlen)
159                         goto out_cont;
160
161                 if (m->type == W1_MASTER_CMD) {
162                         dev = w1_search_master_id(m->id.mst.id);
163                 } else if (m->type == W1_SLAVE_CMD) {
164                         sl = w1_search_slave(&id);
165                         if (sl)
166                                 dev = sl->master;
167                 }
168
169                 if (!dev) {
170                         err = -ENODEV;
171                         goto out_cont;
172                 }
173
174                 mutex_lock(&dev->mutex);
175
176                 if (sl && w1_reset_select_slave(sl)) {
177                         err = -ENODEV;
178                         goto out_up;
179                 }
180
181                 while (mlen) {
182                         cmd = (struct w1_netlink_cmd *)cmd_data;
183
184                         if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) {
185                                 err = -E2BIG;
186                                 break;
187                         }
188
189                         if (sl)
190                                 w1_process_command_slave(sl, msg, m, cmd);
191                         else
192                                 w1_process_command_master(dev, msg, m, cmd);
193
194                         cmd_data += cmd->len + sizeof(struct w1_netlink_cmd);
195                         mlen -= cmd->len + sizeof(struct w1_netlink_cmd);
196                 }
197 out_up:
198                 atomic_dec(&dev->refcnt);
199                 if (sl)
200                         atomic_dec(&sl->refcnt);
201                 mutex_unlock(&dev->mutex);
202 out_cont:
203                 msg->len -= sizeof(struct w1_netlink_msg) + m->len;
204                 m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len);
205
206                 /*
207                  * Let's allow requests for nonexisting devices.
208                  */
209                 if (err == -ENODEV)
210                         err = 0;
211         }
212 #if 0
213         if (err) {
214                 printk("%s: malformed message. Dropping.\n", __func__);
215         }
216 #endif
217 }
218
219 int w1_init_netlink(void)
220 {
221         struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
222
223         return cn_add_callback(&w1_id, "w1", &w1_cn_callback);
224 }
225
226 void w1_fini_netlink(void)
227 {
228         struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
229
230         cn_del_callback(&w1_id);
231 }
232 #else
233 void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
234 {
235 }
236
237 int w1_init_netlink(void)
238 {
239         return 0;
240 }
241
242 void w1_fini_netlink(void)
243 {
244 }
245 #endif