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/device.h>
28 #include <linux/types.h>
29 #include <linux/delay.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_name(struct device
*, struct device_attribute
*attr
, char *);
46 static ssize_t
w1_therm_read_temp(struct device
*, struct device_attribute
*attr
, char *);
47 static ssize_t
w1_therm_read_bin(struct kobject
*, char *, loff_t
, size_t);
49 static struct w1_family_ops w1_therm_fops
= {
50 .rname
= &w1_therm_read_name
,
51 .rbin
= &w1_therm_read_bin
,
52 .rval
= &w1_therm_read_temp
,
53 .rvalname
= "temp1_input",
56 static struct w1_family w1_therm_family_DS18S20
= {
57 .fid
= W1_THERM_DS18S20
,
58 .fops
= &w1_therm_fops
,
61 static struct w1_family w1_therm_family_DS18B20
= {
62 .fid
= W1_THERM_DS18B20
,
63 .fops
= &w1_therm_fops
,
65 static struct w1_family w1_therm_family_DS1822
= {
66 .fid
= W1_THERM_DS1822
,
67 .fops
= &w1_therm_fops
,
70 struct w1_therm_family_converter
76 int (*convert
)(u8 rom
[9]);
79 static inline int w1_DS18B20_convert_temp(u8 rom
[9]);
80 static inline int w1_DS18S20_convert_temp(u8 rom
[9]);
82 static struct w1_therm_family_converter w1_therm_families
[] = {
84 .fid
= W1_THERM_DS18S20
,
85 .f
= &w1_therm_family_DS18S20
,
86 .convert
= w1_DS18S20_convert_temp
89 .fid
= W1_THERM_DS1822
,
90 .f
= &w1_therm_family_DS1822
,
91 .convert
= w1_DS18B20_convert_temp
94 .fid
= W1_THERM_DS18B20
,
95 .f
= &w1_therm_family_DS18B20
,
96 .convert
= w1_DS18B20_convert_temp
100 static ssize_t
w1_therm_read_name(struct device
*dev
, struct device_attribute
*attr
, char *buf
)
102 struct w1_slave
*sl
= container_of(dev
, struct w1_slave
, dev
);
104 return sprintf(buf
, "%s\n", sl
->name
);
107 static inline int w1_DS18B20_convert_temp(u8 rom
[9])
109 int t
= (rom
[1] << 8) | rom
[0];
114 static inline int w1_DS18S20_convert_temp(u8 rom
[9])
122 t
= ((s32
)rom
[0] >> 1)*1000;
124 t
= 1000*(-1*(s32
)(0x100-rom
[0]) >> 1);
127 h
= 1000*((s32
)rom
[7] - (s32
)rom
[6]);
134 static inline int w1_convert_temp(u8 rom
[9], u8 fid
)
138 for (i
=0; i
<sizeof(w1_therm_families
)/sizeof(w1_therm_families
[0]); ++i
)
139 if (w1_therm_families
[i
].fid
== fid
)
140 return w1_therm_families
[i
].convert(rom
);
145 static ssize_t
w1_therm_read_temp(struct device
*dev
, struct device_attribute
*attr
, char *buf
)
147 struct w1_slave
*sl
= container_of(dev
, struct w1_slave
, dev
);
149 return sprintf(buf
, "%d\n", w1_convert_temp(sl
->rom
, sl
->family
->fid
));
152 static int w1_therm_check_rom(u8 rom
[9])
156 for (i
=0; i
<sizeof(bad_roms
)/9; ++i
)
157 if (!memcmp(bad_roms
[i
], rom
, 9))
163 static ssize_t
w1_therm_read_bin(struct kobject
*kobj
, char *buf
, loff_t off
, size_t count
)
165 struct w1_slave
*sl
= container_of(container_of(kobj
, struct device
, kobj
),
166 struct w1_slave
, dev
);
167 struct w1_master
*dev
= sl
->master
;
168 u8 rom
[9], crc
, verdict
;
169 int i
, max_trying
= 10;
171 atomic_inc(&sl
->refcnt
);
172 smp_mb__after_atomic_inc();
173 if (down_interruptible(&sl
->master
->mutex
)) {
178 if (off
> W1_SLAVE_DATA_SIZE
) {
182 if (off
+ count
> W1_SLAVE_DATA_SIZE
) {
187 memset(buf
, 0, count
);
188 memset(rom
, 0, sizeof(rom
));
194 while (max_trying
--) {
195 if (!w1_reset_bus (dev
)) {
197 u8 match
[9] = {W1_MATCH_ROM
, };
198 unsigned int tm
= 750;
200 memcpy(&match
[1], (u64
*) & sl
->reg_num
, 8);
202 w1_write_block(dev
, match
, 9);
204 w1_write_8(dev
, W1_CONVERT_TEMP
);
207 tm
= msleep_interruptible(tm
);
208 if (signal_pending(current
))
209 flush_signals(current
);
212 if (!w1_reset_bus (dev
)) {
213 w1_write_block(dev
, match
, 9);
215 w1_write_8(dev
, W1_READ_SCRATCHPAD
);
216 if ((count
= w1_read_block(dev
, rom
, 9)) != 9) {
217 dev_warn(&dev
->dev
, "w1_read_block() returned %d instead of 9.\n", count
);
220 crc
= w1_calc_crc8(rom
, 8);
222 if (rom
[8] == crc
&& rom
[0])
228 if (!w1_therm_check_rom(rom
))
232 for (i
= 0; i
< 9; ++i
)
233 count
+= sprintf(buf
+ count
, "%02x ", rom
[i
]);
234 count
+= sprintf(buf
+ count
, ": crc=%02x %s\n",
235 crc
, (verdict
) ? "YES" : "NO");
237 memcpy(sl
->rom
, rom
, sizeof(sl
->rom
));
239 dev_warn(&dev
->dev
, "18S20 doesn't respond to CONVERT_TEMP.\n");
241 for (i
= 0; i
< 9; ++i
)
242 count
+= sprintf(buf
+ count
, "%02x ", sl
->rom
[i
]);
244 count
+= sprintf(buf
+ count
, "t=%d\n", w1_convert_temp(rom
, sl
->family
->fid
));
248 smp_mb__before_atomic_inc();
249 atomic_dec(&sl
->refcnt
);
254 static int __init
w1_therm_init(void)
258 for (i
=0; i
<sizeof(w1_therm_families
)/sizeof(w1_therm_families
[0]); ++i
) {
259 err
= w1_register_family(w1_therm_families
[i
].f
);
261 w1_therm_families
[i
].broken
= 1;
267 static void __exit
w1_therm_fini(void)
271 for (i
=0; i
<sizeof(w1_therm_families
)/sizeof(w1_therm_families
[0]); ++i
)
272 if (!w1_therm_families
[i
].broken
)
273 w1_unregister_family(w1_therm_families
[i
].f
);
276 module_init(w1_therm_init
);
277 module_exit(w1_therm_fini
);