Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
7785925d | 2 | * w1_therm.c |
1da177e4 LT |
3 | * |
4 | * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru> | |
7785925d | 5 | * |
1da177e4 LT |
6 | * |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the therms 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 <asm/types.h> | |
23 | ||
24 | #include <linux/kernel.h> | |
25 | #include <linux/module.h> | |
26 | #include <linux/moduleparam.h> | |
27 | #include <linux/device.h> | |
28 | #include <linux/types.h> | |
29 | #include <linux/delay.h> | |
30 | ||
31 | #include "w1.h" | |
32 | #include "w1_io.h" | |
33 | #include "w1_int.h" | |
34 | #include "w1_family.h" | |
35 | ||
36 | MODULE_LICENSE("GPL"); | |
37 | MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>"); | |
38 | MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol, temperature family."); | |
39 | ||
40 | static u8 bad_roms[][9] = { | |
7785925d | 41 | {0xaa, 0x00, 0x4b, 0x46, 0xff, 0xff, 0x0c, 0x10, 0x87}, |
1da177e4 LT |
42 | {} |
43 | }; | |
44 | ||
1da177e4 LT |
45 | static ssize_t w1_therm_read_bin(struct kobject *, char *, loff_t, size_t); |
46 | ||
d2a4ef6a EP |
47 | static struct bin_attribute w1_therm_bin_attr = { |
48 | .attr = { | |
49 | .name = "w1_slave", | |
50 | .mode = S_IRUGO, | |
51 | .owner = THIS_MODULE, | |
52 | }, | |
53 | .size = W1_SLAVE_DATA_SIZE, | |
54 | .read = w1_therm_read_bin, | |
55 | }; | |
56 | ||
57 | static int w1_therm_add_slave(struct w1_slave *sl) | |
58 | { | |
59 | return sysfs_create_bin_file(&sl->dev.kobj, &w1_therm_bin_attr); | |
60 | } | |
61 | ||
62 | static void w1_therm_remove_slave(struct w1_slave *sl) | |
63 | { | |
64 | sysfs_remove_bin_file(&sl->dev.kobj, &w1_therm_bin_attr); | |
65 | } | |
66 | ||
1da177e4 | 67 | static struct w1_family_ops w1_therm_fops = { |
d2a4ef6a EP |
68 | .add_slave = w1_therm_add_slave, |
69 | .remove_slave = w1_therm_remove_slave, | |
1da177e4 LT |
70 | }; |
71 | ||
718a538f EP |
72 | static struct w1_family w1_therm_family_DS18S20 = { |
73 | .fid = W1_THERM_DS18S20, | |
74 | .fops = &w1_therm_fops, | |
75 | }; | |
76 | ||
77 | static struct w1_family w1_therm_family_DS18B20 = { | |
78 | .fid = W1_THERM_DS18B20, | |
79 | .fops = &w1_therm_fops, | |
80 | }; | |
d2a4ef6a | 81 | |
718a538f EP |
82 | static struct w1_family w1_therm_family_DS1822 = { |
83 | .fid = W1_THERM_DS1822, | |
84 | .fops = &w1_therm_fops, | |
85 | }; | |
86 | ||
87 | struct w1_therm_family_converter | |
88 | { | |
718a538f EP |
89 | u8 broken; |
90 | u16 reserved; | |
91 | struct w1_family *f; | |
92 | int (*convert)(u8 rom[9]); | |
93 | }; | |
94 | ||
95 | static inline int w1_DS18B20_convert_temp(u8 rom[9]); | |
96 | static inline int w1_DS18S20_convert_temp(u8 rom[9]); | |
97 | ||
98 | static struct w1_therm_family_converter w1_therm_families[] = { | |
99 | { | |
718a538f EP |
100 | .f = &w1_therm_family_DS18S20, |
101 | .convert = w1_DS18S20_convert_temp | |
102 | }, | |
103 | { | |
718a538f EP |
104 | .f = &w1_therm_family_DS1822, |
105 | .convert = w1_DS18B20_convert_temp | |
106 | }, | |
107 | { | |
718a538f EP |
108 | .f = &w1_therm_family_DS18B20, |
109 | .convert = w1_DS18B20_convert_temp | |
110 | }, | |
111 | }; | |
112 | ||
718a538f EP |
113 | static inline int w1_DS18B20_convert_temp(u8 rom[9]) |
114 | { | |
115 | int t = (rom[1] << 8) | rom[0]; | |
116 | t /= 16; | |
117 | return t; | |
118 | } | |
119 | ||
120 | static inline int w1_DS18S20_convert_temp(u8 rom[9]) | |
1da177e4 LT |
121 | { |
122 | int t, h; | |
718a538f EP |
123 | |
124 | if (!rom[7]) | |
125 | return 0; | |
1da177e4 LT |
126 | |
127 | if (rom[1] == 0) | |
128 | t = ((s32)rom[0] >> 1)*1000; | |
129 | else | |
130 | t = 1000*(-1*(s32)(0x100-rom[0]) >> 1); | |
131 | ||
132 | t -= 250; | |
133 | h = 1000*((s32)rom[7] - (s32)rom[6]); | |
134 | h /= (s32)rom[7]; | |
135 | t += h; | |
136 | ||
137 | return t; | |
138 | } | |
139 | ||
718a538f EP |
140 | static inline int w1_convert_temp(u8 rom[9], u8 fid) |
141 | { | |
142 | int i; | |
143 | ||
144 | for (i=0; i<sizeof(w1_therm_families)/sizeof(w1_therm_families[0]); ++i) | |
4e470aa9 | 145 | if (w1_therm_families[i].f->fid == fid) |
718a538f EP |
146 | return w1_therm_families[i].convert(rom); |
147 | ||
148 | return 0; | |
149 | } | |
150 | ||
1da177e4 LT |
151 | static int w1_therm_check_rom(u8 rom[9]) |
152 | { | |
153 | int i; | |
154 | ||
155 | for (i=0; i<sizeof(bad_roms)/9; ++i) | |
156 | if (!memcmp(bad_roms[i], rom, 9)) | |
157 | return 1; | |
158 | ||
159 | return 0; | |
160 | } | |
161 | ||
162 | static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, size_t count) | |
163 | { | |
db2d0008 | 164 | struct w1_slave *sl = kobj_to_w1_slave(kobj); |
1da177e4 LT |
165 | struct w1_master *dev = sl->master; |
166 | u8 rom[9], crc, verdict; | |
167 | int i, max_trying = 10; | |
168 | ||
169 | atomic_inc(&sl->refcnt); | |
170 | smp_mb__after_atomic_inc(); | |
171 | if (down_interruptible(&sl->master->mutex)) { | |
172 | count = 0; | |
173 | goto out_dec; | |
174 | } | |
175 | ||
176 | if (off > W1_SLAVE_DATA_SIZE) { | |
177 | count = 0; | |
178 | goto out; | |
179 | } | |
180 | if (off + count > W1_SLAVE_DATA_SIZE) { | |
181 | count = 0; | |
182 | goto out; | |
183 | } | |
184 | ||
185 | memset(buf, 0, count); | |
186 | memset(rom, 0, sizeof(rom)); | |
187 | ||
188 | count = 0; | |
189 | verdict = 0; | |
190 | crc = 0; | |
191 | ||
192 | while (max_trying--) { | |
ea7d8f65 | 193 | if (!w1_reset_select_slave(sl)) { |
1da177e4 | 194 | int count = 0; |
1da177e4 LT |
195 | unsigned int tm = 750; |
196 | ||
1da177e4 LT |
197 | w1_write_8(dev, W1_CONVERT_TEMP); |
198 | ||
199 | while (tm) { | |
200 | tm = msleep_interruptible(tm); | |
201 | if (signal_pending(current)) | |
202 | flush_signals(current); | |
203 | } | |
204 | ||
ea7d8f65 | 205 | if (!w1_reset_select_slave(sl)) { |
7785925d | 206 | |
1da177e4 LT |
207 | w1_write_8(dev, W1_READ_SCRATCHPAD); |
208 | if ((count = w1_read_block(dev, rom, 9)) != 9) { | |
209 | dev_warn(&dev->dev, "w1_read_block() returned %d instead of 9.\n", count); | |
210 | } | |
211 | ||
212 | crc = w1_calc_crc8(rom, 8); | |
213 | ||
214 | if (rom[8] == crc && rom[0]) | |
215 | verdict = 1; | |
1da177e4 LT |
216 | } |
217 | } | |
218 | ||
219 | if (!w1_therm_check_rom(rom)) | |
220 | break; | |
221 | } | |
222 | ||
223 | for (i = 0; i < 9; ++i) | |
224 | count += sprintf(buf + count, "%02x ", rom[i]); | |
225 | count += sprintf(buf + count, ": crc=%02x %s\n", | |
226 | crc, (verdict) ? "YES" : "NO"); | |
227 | if (verdict) | |
228 | memcpy(sl->rom, rom, sizeof(sl->rom)); | |
229 | else | |
230 | dev_warn(&dev->dev, "18S20 doesn't respond to CONVERT_TEMP.\n"); | |
231 | ||
232 | for (i = 0; i < 9; ++i) | |
233 | count += sprintf(buf + count, "%02x ", sl->rom[i]); | |
234 | ||
718a538f | 235 | count += sprintf(buf + count, "t=%d\n", w1_convert_temp(rom, sl->family->fid)); |
1da177e4 LT |
236 | out: |
237 | up(&dev->mutex); | |
238 | out_dec: | |
239 | smp_mb__before_atomic_inc(); | |
240 | atomic_dec(&sl->refcnt); | |
241 | ||
242 | return count; | |
243 | } | |
244 | ||
1da177e4 LT |
245 | static int __init w1_therm_init(void) |
246 | { | |
718a538f EP |
247 | int err, i; |
248 | ||
249 | for (i=0; i<sizeof(w1_therm_families)/sizeof(w1_therm_families[0]); ++i) { | |
250 | err = w1_register_family(w1_therm_families[i].f); | |
251 | if (err) | |
252 | w1_therm_families[i].broken = 1; | |
253 | } | |
254 | ||
255 | return 0; | |
1da177e4 LT |
256 | } |
257 | ||
258 | static void __exit w1_therm_fini(void) | |
259 | { | |
718a538f EP |
260 | int i; |
261 | ||
262 | for (i=0; i<sizeof(w1_therm_families)/sizeof(w1_therm_families[0]); ++i) | |
263 | if (!w1_therm_families[i].broken) | |
264 | w1_unregister_family(w1_therm_families[i].f); | |
1da177e4 LT |
265 | } |
266 | ||
267 | module_init(w1_therm_init); | |
268 | module_exit(w1_therm_fini); |