4 * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
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.
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.
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
22 #include <asm/types.h>
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/moduleparam.h>
27 #include <linux/sched.h>
28 #include <linux/device.h>
29 #include <linux/types.h>
30 #include <linux/delay.h>
33 #include "../w1_int.h"
34 #include "../w1_family.h"
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.");
40 static u8 bad_roms
[][9] = {
41 {0xaa, 0x00, 0x4b, 0x46, 0xff, 0xff, 0x0c, 0x10, 0x87},
45 static ssize_t
w1_therm_read_bin(struct kobject
*, struct bin_attribute
*,
46 char *, loff_t
, size_t);
48 static struct bin_attribute w1_therm_bin_attr
= {
53 .size
= W1_SLAVE_DATA_SIZE
,
54 .read
= w1_therm_read_bin
,
57 static int w1_therm_add_slave(struct w1_slave
*sl
)
59 return sysfs_create_bin_file(&sl
->dev
.kobj
, &w1_therm_bin_attr
);
62 static void w1_therm_remove_slave(struct w1_slave
*sl
)
64 sysfs_remove_bin_file(&sl
->dev
.kobj
, &w1_therm_bin_attr
);
67 static struct w1_family_ops w1_therm_fops
= {
68 .add_slave
= w1_therm_add_slave
,
69 .remove_slave
= w1_therm_remove_slave
,
72 static struct w1_family w1_therm_family_DS18S20
= {
73 .fid
= W1_THERM_DS18S20
,
74 .fops
= &w1_therm_fops
,
77 static struct w1_family w1_therm_family_DS18B20
= {
78 .fid
= W1_THERM_DS18B20
,
79 .fops
= &w1_therm_fops
,
82 static struct w1_family w1_therm_family_DS1822
= {
83 .fid
= W1_THERM_DS1822
,
84 .fops
= &w1_therm_fops
,
87 struct w1_therm_family_converter
92 int (*convert
)(u8 rom
[9]);
95 static inline int w1_DS18B20_convert_temp(u8 rom
[9]);
96 static inline int w1_DS18S20_convert_temp(u8 rom
[9]);
98 static struct w1_therm_family_converter w1_therm_families
[] = {
100 .f
= &w1_therm_family_DS18S20
,
101 .convert
= w1_DS18S20_convert_temp
104 .f
= &w1_therm_family_DS1822
,
105 .convert
= w1_DS18B20_convert_temp
108 .f
= &w1_therm_family_DS18B20
,
109 .convert
= w1_DS18B20_convert_temp
113 static inline int w1_DS18B20_convert_temp(u8 rom
[9])
115 s16 t
= (rom
[1] << 8) | rom
[0];
120 static inline int w1_DS18S20_convert_temp(u8 rom
[9])
128 t
= ((s32
)rom
[0] >> 1)*1000;
130 t
= 1000*(-1*(s32
)(0x100-rom
[0]) >> 1);
133 h
= 1000*((s32
)rom
[7] - (s32
)rom
[6]);
140 static inline int w1_convert_temp(u8 rom
[9], u8 fid
)
144 for (i
= 0; i
< ARRAY_SIZE(w1_therm_families
); ++i
)
145 if (w1_therm_families
[i
].f
->fid
== fid
)
146 return w1_therm_families
[i
].convert(rom
);
151 static int w1_therm_check_rom(u8 rom
[9])
155 for (i
=0; i
<sizeof(bad_roms
)/9; ++i
)
156 if (!memcmp(bad_roms
[i
], rom
, 9))
162 static ssize_t
w1_therm_read_bin(struct kobject
*kobj
,
163 struct bin_attribute
*bin_attr
,
164 char *buf
, loff_t off
, size_t count
)
166 struct w1_slave
*sl
= kobj_to_w1_slave(kobj
);
167 struct w1_master
*dev
= sl
->master
;
168 u8 rom
[9], crc
, verdict
;
169 int i
, max_trying
= 10;
171 mutex_lock(&sl
->master
->mutex
);
173 if (off
> W1_SLAVE_DATA_SIZE
) {
177 if (off
+ count
> W1_SLAVE_DATA_SIZE
) {
182 memset(buf
, 0, count
);
183 memset(rom
, 0, sizeof(rom
));
189 while (max_trying
--) {
190 if (!w1_reset_select_slave(sl
)) {
192 unsigned int tm
= 750;
194 w1_write_8(dev
, W1_CONVERT_TEMP
);
198 if (!w1_reset_select_slave(sl
)) {
200 w1_write_8(dev
, W1_READ_SCRATCHPAD
);
201 if ((count
= w1_read_block(dev
, rom
, 9)) != 9) {
202 dev_warn(&dev
->dev
, "w1_read_block() returned %d instead of 9.\n", count
);
205 crc
= w1_calc_crc8(rom
, 8);
212 if (!w1_therm_check_rom(rom
))
216 for (i
= 0; i
< 9; ++i
)
217 count
+= sprintf(buf
+ count
, "%02x ", rom
[i
]);
218 count
+= sprintf(buf
+ count
, ": crc=%02x %s\n",
219 crc
, (verdict
) ? "YES" : "NO");
221 memcpy(sl
->rom
, rom
, sizeof(sl
->rom
));
223 dev_warn(&dev
->dev
, "18S20 doesn't respond to CONVERT_TEMP.\n");
225 for (i
= 0; i
< 9; ++i
)
226 count
+= sprintf(buf
+ count
, "%02x ", sl
->rom
[i
]);
228 count
+= sprintf(buf
+ count
, "t=%d\n", w1_convert_temp(rom
, sl
->family
->fid
));
230 mutex_unlock(&dev
->mutex
);
235 static int __init
w1_therm_init(void)
239 for (i
= 0; i
< ARRAY_SIZE(w1_therm_families
); ++i
) {
240 err
= w1_register_family(w1_therm_families
[i
].f
);
242 w1_therm_families
[i
].broken
= 1;
248 static void __exit
w1_therm_fini(void)
252 for (i
= 0; i
< ARRAY_SIZE(w1_therm_families
); ++i
)
253 if (!w1_therm_families
[i
].broken
)
254 w1_unregister_family(w1_therm_families
[i
].f
);
257 module_init(w1_therm_init
);
258 module_exit(w1_therm_fini
);