Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Evgeniy Polyakov | 7785925 | 2005-05-20 22:33:25 +0400 | [diff] [blame] | 2 | * w1_therm.c |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3 | * |
| 4 | * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru> |
Evgeniy Polyakov | 7785925 | 2005-05-20 22:33:25 +0400 | [diff] [blame] | 5 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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] = { |
Evgeniy Polyakov | 7785925 | 2005-05-20 22:33:25 +0400 | [diff] [blame] | 41 | {0xaa, 0x00, 0x4b, 0x46, 0xff, 0xff, 0x0c, 0x10, 0x87}, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | {} |
| 43 | }; |
| 44 | |
Yani Ioannou | 060b884 | 2005-05-17 06:44:04 -0400 | [diff] [blame] | 45 | static ssize_t w1_therm_read_name(struct device *, struct device_attribute *attr, char *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | static ssize_t w1_therm_read_bin(struct kobject *, char *, loff_t, size_t); |
| 47 | |
| 48 | static struct w1_family_ops w1_therm_fops = { |
| 49 | .rname = &w1_therm_read_name, |
| 50 | .rbin = &w1_therm_read_bin, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | }; |
| 52 | |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 53 | static struct w1_family w1_therm_family_DS18S20 = { |
| 54 | .fid = W1_THERM_DS18S20, |
| 55 | .fops = &w1_therm_fops, |
| 56 | }; |
| 57 | |
| 58 | static struct w1_family w1_therm_family_DS18B20 = { |
| 59 | .fid = W1_THERM_DS18B20, |
| 60 | .fops = &w1_therm_fops, |
| 61 | }; |
| 62 | static struct w1_family w1_therm_family_DS1822 = { |
| 63 | .fid = W1_THERM_DS1822, |
| 64 | .fops = &w1_therm_fops, |
| 65 | }; |
| 66 | |
| 67 | struct w1_therm_family_converter |
| 68 | { |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 69 | u8 broken; |
| 70 | u16 reserved; |
| 71 | struct w1_family *f; |
| 72 | int (*convert)(u8 rom[9]); |
| 73 | }; |
| 74 | |
| 75 | static inline int w1_DS18B20_convert_temp(u8 rom[9]); |
| 76 | static inline int w1_DS18S20_convert_temp(u8 rom[9]); |
| 77 | |
| 78 | static struct w1_therm_family_converter w1_therm_families[] = { |
| 79 | { |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 80 | .f = &w1_therm_family_DS18S20, |
| 81 | .convert = w1_DS18S20_convert_temp |
| 82 | }, |
| 83 | { |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 84 | .f = &w1_therm_family_DS1822, |
| 85 | .convert = w1_DS18B20_convert_temp |
| 86 | }, |
| 87 | { |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 88 | .f = &w1_therm_family_DS18B20, |
| 89 | .convert = w1_DS18B20_convert_temp |
| 90 | }, |
| 91 | }; |
| 92 | |
Yani Ioannou | 060b884 | 2005-05-17 06:44:04 -0400 | [diff] [blame] | 93 | static ssize_t w1_therm_read_name(struct device *dev, struct device_attribute *attr, char *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | { |
Evgeniy Polyakov | db2d000 | 2005-08-11 17:27:49 +0400 | [diff] [blame] | 95 | struct w1_slave *sl = dev_to_w1_slave(dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | return sprintf(buf, "%s\n", sl->name); |
| 97 | } |
| 98 | |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 99 | static inline int w1_DS18B20_convert_temp(u8 rom[9]) |
| 100 | { |
| 101 | int t = (rom[1] << 8) | rom[0]; |
| 102 | t /= 16; |
| 103 | return t; |
| 104 | } |
| 105 | |
| 106 | static inline int w1_DS18S20_convert_temp(u8 rom[9]) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | { |
| 108 | int t, h; |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 109 | |
| 110 | if (!rom[7]) |
| 111 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | |
| 113 | if (rom[1] == 0) |
| 114 | t = ((s32)rom[0] >> 1)*1000; |
| 115 | else |
| 116 | t = 1000*(-1*(s32)(0x100-rom[0]) >> 1); |
| 117 | |
| 118 | t -= 250; |
| 119 | h = 1000*((s32)rom[7] - (s32)rom[6]); |
| 120 | h /= (s32)rom[7]; |
| 121 | t += h; |
| 122 | |
| 123 | return t; |
| 124 | } |
| 125 | |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 126 | static inline int w1_convert_temp(u8 rom[9], u8 fid) |
| 127 | { |
| 128 | int i; |
| 129 | |
| 130 | for (i=0; i<sizeof(w1_therm_families)/sizeof(w1_therm_families[0]); ++i) |
Evgeniy Polyakov | 4e470aa | 2005-05-20 22:50:33 +0400 | [diff] [blame] | 131 | if (w1_therm_families[i].f->fid == fid) |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 132 | return w1_therm_families[i].convert(rom); |
| 133 | |
| 134 | return 0; |
| 135 | } |
| 136 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | static int w1_therm_check_rom(u8 rom[9]) |
| 138 | { |
| 139 | int i; |
| 140 | |
| 141 | for (i=0; i<sizeof(bad_roms)/9; ++i) |
| 142 | if (!memcmp(bad_roms[i], rom, 9)) |
| 143 | return 1; |
| 144 | |
| 145 | return 0; |
| 146 | } |
| 147 | |
| 148 | static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, size_t count) |
| 149 | { |
Evgeniy Polyakov | db2d000 | 2005-08-11 17:27:49 +0400 | [diff] [blame] | 150 | struct w1_slave *sl = kobj_to_w1_slave(kobj); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | struct w1_master *dev = sl->master; |
| 152 | u8 rom[9], crc, verdict; |
| 153 | int i, max_trying = 10; |
| 154 | |
| 155 | atomic_inc(&sl->refcnt); |
| 156 | smp_mb__after_atomic_inc(); |
| 157 | if (down_interruptible(&sl->master->mutex)) { |
| 158 | count = 0; |
| 159 | goto out_dec; |
| 160 | } |
| 161 | |
| 162 | if (off > W1_SLAVE_DATA_SIZE) { |
| 163 | count = 0; |
| 164 | goto out; |
| 165 | } |
| 166 | if (off + count > W1_SLAVE_DATA_SIZE) { |
| 167 | count = 0; |
| 168 | goto out; |
| 169 | } |
| 170 | |
| 171 | memset(buf, 0, count); |
| 172 | memset(rom, 0, sizeof(rom)); |
| 173 | |
| 174 | count = 0; |
| 175 | verdict = 0; |
| 176 | crc = 0; |
| 177 | |
| 178 | while (max_trying--) { |
Evgeniy Polyakov | ea7d8f6 | 2005-08-11 17:27:49 +0400 | [diff] [blame^] | 179 | if (!w1_reset_select_slave(sl)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | int count = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | unsigned int tm = 750; |
| 182 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | w1_write_8(dev, W1_CONVERT_TEMP); |
| 184 | |
| 185 | while (tm) { |
| 186 | tm = msleep_interruptible(tm); |
| 187 | if (signal_pending(current)) |
| 188 | flush_signals(current); |
| 189 | } |
| 190 | |
Evgeniy Polyakov | ea7d8f6 | 2005-08-11 17:27:49 +0400 | [diff] [blame^] | 191 | if (!w1_reset_select_slave(sl)) { |
Evgeniy Polyakov | 7785925 | 2005-05-20 22:33:25 +0400 | [diff] [blame] | 192 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | w1_write_8(dev, W1_READ_SCRATCHPAD); |
| 194 | if ((count = w1_read_block(dev, rom, 9)) != 9) { |
| 195 | dev_warn(&dev->dev, "w1_read_block() returned %d instead of 9.\n", count); |
| 196 | } |
| 197 | |
| 198 | crc = w1_calc_crc8(rom, 8); |
| 199 | |
| 200 | if (rom[8] == crc && rom[0]) |
| 201 | verdict = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 202 | } |
| 203 | } |
| 204 | |
| 205 | if (!w1_therm_check_rom(rom)) |
| 206 | break; |
| 207 | } |
| 208 | |
| 209 | for (i = 0; i < 9; ++i) |
| 210 | count += sprintf(buf + count, "%02x ", rom[i]); |
| 211 | count += sprintf(buf + count, ": crc=%02x %s\n", |
| 212 | crc, (verdict) ? "YES" : "NO"); |
| 213 | if (verdict) |
| 214 | memcpy(sl->rom, rom, sizeof(sl->rom)); |
| 215 | else |
| 216 | dev_warn(&dev->dev, "18S20 doesn't respond to CONVERT_TEMP.\n"); |
| 217 | |
| 218 | for (i = 0; i < 9; ++i) |
| 219 | count += sprintf(buf + count, "%02x ", sl->rom[i]); |
| 220 | |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 221 | count += sprintf(buf + count, "t=%d\n", w1_convert_temp(rom, sl->family->fid)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 222 | out: |
| 223 | up(&dev->mutex); |
| 224 | out_dec: |
| 225 | smp_mb__before_atomic_inc(); |
| 226 | atomic_dec(&sl->refcnt); |
| 227 | |
| 228 | return count; |
| 229 | } |
| 230 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | static int __init w1_therm_init(void) |
| 232 | { |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 233 | int err, i; |
| 234 | |
| 235 | for (i=0; i<sizeof(w1_therm_families)/sizeof(w1_therm_families[0]); ++i) { |
| 236 | err = w1_register_family(w1_therm_families[i].f); |
| 237 | if (err) |
| 238 | w1_therm_families[i].broken = 1; |
| 239 | } |
| 240 | |
| 241 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 242 | } |
| 243 | |
| 244 | static void __exit w1_therm_fini(void) |
| 245 | { |
Evgeniy Polyakov | 718a538 | 2005-04-17 22:58:14 +0400 | [diff] [blame] | 246 | int i; |
| 247 | |
| 248 | for (i=0; i<sizeof(w1_therm_families)/sizeof(w1_therm_families[0]); ++i) |
| 249 | if (!w1_therm_families[i].broken) |
| 250 | w1_unregister_family(w1_therm_families[i].f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | } |
| 252 | |
| 253 | module_init(w1_therm_init); |
| 254 | module_exit(w1_therm_fini); |