1 /*- 2 * Copyright (c) 2015 M. Warner Losh <imp@FreeBSD.org> 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice unmodified, this list of conditions, and the following 9 * disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include <sys/cdefs.h> 27 __FBSDID("$FreeBSD$"); 28 29 #include <sys/param.h> 30 #include <sys/systm.h> 31 #include <sys/kernel.h> 32 33 #include <sys/bus.h> 34 #include <sys/errno.h> 35 #include <sys/libkern.h> 36 #include <sys/kthread.h> 37 #include <sys/malloc.h> 38 #include <sys/module.h> 39 #include <sys/mutex.h> 40 #include <sys/proc.h> 41 #include <sys/sysctl.h> 42 43 #include <dev/ow/ow.h> 44 #include <dev/ow/own.h> 45 46 #define OWT_DS1820 0x10 /* Also 18S20 */ 47 #define OWT_DS1822 0x22 /* Very close to 18B20 */ 48 #define OWT_DS18B20 0x28 /* Also MAX31820 */ 49 #define OWT_DS1825 0x3B /* Just like 18B20 with address bits */ 50 51 #define CONVERT_T 0x44 52 #define COPY_SCRATCHPAD 0x48 53 #define WRITE_SCRATCHPAD 0x4e 54 #define READ_POWER_SUPPLY 0xb4 55 #define RECALL_EE 0xb8 56 #define READ_SCRATCHPAD 0xbe 57 58 #define OW_TEMP_DONE 0x01 59 #define OW_TEMP_RUNNING 0x02 60 61 struct ow_temp_softc 62 { 63 device_t dev; 64 int type; 65 int temp; 66 int flags; 67 int bad_crc; 68 int bad_reads; 69 int reading_interval; 70 int parasite; 71 struct mtx temp_lock; 72 struct proc *event_thread; 73 }; 74 75 static int 76 ow_temp_probe(device_t dev) 77 { 78 79 switch (ow_get_family(dev)) { 80 case OWT_DS1820: 81 device_set_desc(dev, "One Wire Temperature"); 82 return BUS_PROBE_DEFAULT; 83 case OWT_DS1822: 84 case OWT_DS1825: 85 case OWT_DS18B20: 86 device_set_desc(dev, "Advanced One Wire Temperature"); 87 return BUS_PROBE_DEFAULT; 88 default: 89 return ENXIO; 90 } 91 } 92 93 static int 94 ow_temp_read_scratchpad(device_t dev, uint8_t *scratch, int len) 95 { 96 struct ow_cmd cmd; 97 98 own_self_command(dev, &cmd, READ_SCRATCHPAD); 99 cmd.xpt_read_len = len; 100 own_command_wait(dev, &cmd); 101 memcpy(scratch, cmd.xpt_read, len); 102 103 return 0; 104 } 105 106 static int 107 ow_temp_convert_t(device_t dev) 108 { 109 struct ow_cmd cmd; 110 111 own_self_command(dev, &cmd, CONVERT_T); 112 own_command_wait(dev, &cmd); 113 114 return 0; 115 } 116 117 static int 118 ow_temp_read_power_supply(device_t dev, int *parasite) 119 { 120 struct ow_cmd cmd; 121 122 own_self_command(dev, &cmd, READ_POWER_SUPPLY); 123 cmd.flags |= OW_FLAG_READ_BIT; 124 cmd.xpt_read_len = 1; 125 own_command_wait(dev, &cmd); 126 *parasite = !cmd.xpt_read[0]; /* parasites pull bus low */ 127 128 return 0; 129 } 130 131 static void 132 ow_temp_event_thread(void *arg) 133 { 134 struct ow_temp_softc *sc; 135 uint8_t scratch[8 + 1]; 136 uint8_t crc; 137 int retries, rv, tmp; 138 139 sc = arg; 140 pause("owtstart", device_get_unit(sc->dev) * hz / 100); // 10ms stagger 141 mtx_lock(&sc->temp_lock); 142 sc->flags |= OW_TEMP_RUNNING; 143 mtx_unlock(&sc->temp_lock); 144 ow_temp_read_power_supply(sc->dev, &sc->parasite); 145 if (sc->parasite) 146 device_printf(sc->dev, "Running in parasitic mode unsupported\n"); 147 mtx_lock(&sc->temp_lock); 148 while ((sc->flags & OW_TEMP_DONE) == 0) { 149 mtx_unlock(&sc->temp_lock); 150 ow_temp_convert_t(sc->dev); 151 mtx_lock(&sc->temp_lock); 152 msleep(sc, &sc->temp_lock, 0, "owtcvt", hz); 153 if (sc->flags & OW_TEMP_DONE) 154 break; 155 mtx_unlock(&sc->temp_lock); 156 for (retries = 5; retries > 0; retries--) { 157 rv = ow_temp_read_scratchpad(sc->dev, scratch, sizeof(scratch)); 158 if (rv == 0) { 159 crc = own_crc(sc->dev, scratch, sizeof(scratch) - 1); 160 if (crc == scratch[8]) { 161 if (sc->type == OWT_DS1820) { 162 if (scratch[7]) { 163 /* 164 * Formula from DS18S20 datasheet, page 6 165 * DS18S20 datasheet says count_per_c is 16, DS1820 does not 166 */ 167 tmp = (int16_t)((scratch[0] & 0xfe) | 168 (scratch[1] << 8)) << 3; 169 tmp += 16 - scratch[6] - 4; /* count_per_c == 16 */ 170 } else 171 tmp = (int16_t)(scratch[0] | (scratch[1] << 8)) << 3; 172 } else 173 tmp = (int16_t)(scratch[0] | (scratch[1] << 8)); 174 sc->temp = tmp * 1000 / 16 + 273150; 175 break; 176 } 177 sc->bad_crc++; 178 } else 179 sc->bad_reads++; 180 } 181 mtx_lock(&sc->temp_lock); 182 msleep(sc, &sc->temp_lock, 0, "owtcvt", sc->reading_interval); 183 } 184 sc->flags &= ~OW_TEMP_RUNNING; 185 mtx_unlock(&sc->temp_lock); 186 kproc_exit(0); 187 } 188 189 static int 190 ow_temp_attach(device_t dev) 191 { 192 struct ow_temp_softc *sc; 193 194 sc = device_get_softc(dev); 195 sc->dev = dev; 196 sc->type = ow_get_family(dev); 197 SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev), 198 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 199 OID_AUTO, "temperature", 200 CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_NEEDGIANT, 201 &sc->temp, 0, sysctl_handle_int, 202 "IK3", "Current Temperature"); 203 SYSCTL_ADD_INT(device_get_sysctl_ctx(dev), 204 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 205 OID_AUTO, "badcrc", CTLFLAG_RD, 206 &sc->bad_crc, 0, 207 "Number of Bad CRC on reading scratchpad"); 208 SYSCTL_ADD_INT(device_get_sysctl_ctx(dev), 209 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 210 OID_AUTO, "badread", CTLFLAG_RD, 211 &sc->bad_reads, 0, 212 "Number of errors on reading scratchpad"); 213 SYSCTL_ADD_INT(device_get_sysctl_ctx(dev), 214 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 215 OID_AUTO, "reading_interval", CTLFLAG_RW, 216 &sc->reading_interval, 0, 217 "ticks between reads"); 218 SYSCTL_ADD_INT(device_get_sysctl_ctx(dev), 219 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 220 OID_AUTO, "parasite", CTLFLAG_RW, 221 &sc->parasite, 0, 222 "In Parasite mode"); 223 /* 224 * Just do this for unit 0 to avoid locking 225 * the ow bus until that code can be put 226 * into place. 227 */ 228 sc->temp = -1; 229 sc->reading_interval = 10 * hz; 230 mtx_init(&sc->temp_lock, "lock for doing temperature", NULL, MTX_DEF); 231 /* Start the thread */ 232 if (kproc_create(ow_temp_event_thread, sc, &sc->event_thread, 0, 0, 233 "%s event thread", device_get_nameunit(dev))) { 234 device_printf(dev, "unable to create event thread.\n"); 235 panic("ow_temp_attach, can't create thread"); 236 } 237 238 return 0; 239 } 240 241 static int 242 ow_temp_detach(device_t dev) 243 { 244 struct ow_temp_softc *sc; 245 246 sc = device_get_softc(dev); 247 248 /* 249 * Wait for the thread to die. kproc_exit will do a wakeup 250 * on the event thread's struct thread * so that we know it is 251 * safe to proceed. IF the thread is running, set the please 252 * die flag and wait for it to comply. Since the wakeup on 253 * the event thread happens only in kproc_exit, we don't 254 * need to loop here. 255 */ 256 mtx_lock(&sc->temp_lock); 257 sc->flags |= OW_TEMP_DONE; 258 while (sc->flags & OW_TEMP_RUNNING) { 259 wakeup(sc); 260 msleep(sc->event_thread, &sc->temp_lock, PWAIT, "owtun", 0); 261 } 262 mtx_destroy(&sc->temp_lock); 263 264 return 0; 265 } 266 267 devclass_t ow_temp_devclass; 268 269 static device_method_t ow_temp_methods[] = { 270 /* Device interface */ 271 DEVMETHOD(device_probe, ow_temp_probe), 272 DEVMETHOD(device_attach, ow_temp_attach), 273 DEVMETHOD(device_detach, ow_temp_detach), 274 { 0, 0 } 275 }; 276 277 static driver_t ow_temp_driver = { 278 "ow_temp", 279 ow_temp_methods, 280 sizeof(struct ow_temp_softc), 281 }; 282 283 DRIVER_MODULE(ow_temp, ow, ow_temp_driver, ow_temp_devclass, 0, 0); 284 MODULE_DEPEND(ow_temp, ow, 1, 1, 1); 285