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 59 #define OW_TEMP_DONE 0x01 60 #define OW_TEMP_RUNNING 0x02 61 62 struct ow_temp_softc 63 { 64 device_t dev; 65 int type; 66 int temp; 67 int flags; 68 int bad_crc; 69 int bad_reads; 70 int reading_interval; 71 int parasite; 72 struct mtx temp_lock; 73 struct proc *event_thread; 74 }; 75 76 static int 77 ow_temp_probe(device_t dev) 78 { 79 80 switch (ow_get_family(dev)) { 81 case OWT_DS1820: 82 device_set_desc(dev, "One Wire Temperature"); 83 return BUS_PROBE_DEFAULT; 84 case OWT_DS1822: 85 case OWT_DS1825: 86 case OWT_DS18B20: 87 device_set_desc(dev, "Advanced One Wire Temperature"); 88 return BUS_PROBE_DEFAULT; 89 default: 90 return ENXIO; 91 } 92 } 93 94 static int 95 ow_temp_read_scratchpad(device_t dev, uint8_t *scratch, int len) 96 { 97 struct ow_cmd cmd; 98 99 own_self_command(dev, &cmd, READ_SCRATCHPAD); 100 cmd.xpt_read_len = len; 101 own_command_wait(dev, &cmd); 102 memcpy(scratch, cmd.xpt_read, len); 103 104 return 0; 105 } 106 107 static int 108 ow_temp_convert_t(device_t dev) 109 { 110 struct ow_cmd cmd; 111 112 own_self_command(dev, &cmd, CONVERT_T); 113 own_command_wait(dev, &cmd); 114 115 return 0; 116 } 117 118 119 static int 120 ow_temp_read_power_supply(device_t dev, int *parasite) 121 { 122 struct ow_cmd cmd; 123 124 own_self_command(dev, &cmd, READ_POWER_SUPPLY); 125 cmd.flags |= OW_FLAG_READ_BIT; 126 cmd.xpt_read_len = 1; 127 own_command_wait(dev, &cmd); 128 *parasite = !cmd.xpt_read[0]; /* parasites pull bus low */ 129 130 return 0; 131 } 132 133 static void 134 ow_temp_event_thread(void *arg) 135 { 136 struct ow_temp_softc *sc; 137 uint8_t scratch[8 + 1]; 138 uint8_t crc; 139 int retries, rv, tmp; 140 141 sc = arg; 142 pause("owtstart", device_get_unit(sc->dev) * hz / 100); // 10ms stagger 143 mtx_lock(&sc->temp_lock); 144 sc->flags |= OW_TEMP_RUNNING; 145 mtx_unlock(&sc->temp_lock); 146 ow_temp_read_power_supply(sc->dev, &sc->parasite); 147 if (sc->parasite) 148 device_printf(sc->dev, "Running in parasitic mode unsupported\n"); 149 mtx_lock(&sc->temp_lock); 150 while ((sc->flags & OW_TEMP_DONE) == 0) { 151 mtx_unlock(&sc->temp_lock); 152 ow_temp_convert_t(sc->dev); 153 mtx_lock(&sc->temp_lock); 154 msleep(sc, &sc->temp_lock, 0, "owtcvt", hz); 155 if (sc->flags & OW_TEMP_DONE) 156 break; 157 mtx_unlock(&sc->temp_lock); 158 for (retries = 5; retries > 0; retries--) { 159 rv = ow_temp_read_scratchpad(sc->dev, scratch, sizeof(scratch)); 160 if (rv == 0) { 161 crc = own_crc(sc->dev, scratch, sizeof(scratch) - 1); 162 if (crc == scratch[8]) { 163 if (sc->type == OWT_DS1820) { 164 if (scratch[7]) { 165 /* 166 * Formula from DS18S20 datasheet, page 6 167 * DS18S20 datasheet says count_per_c is 16, DS1820 does not 168 */ 169 tmp = (int16_t)((scratch[0] & 0xfe) | 170 (scratch[1] << 8)) << 3; 171 tmp += 16 - scratch[6] - 4; /* count_per_c == 16 */ 172 } else 173 tmp = (int16_t)(scratch[0] | (scratch[1] << 8)) << 3; 174 } else 175 tmp = (int16_t)(scratch[0] | (scratch[1] << 8)); 176 sc->temp = tmp * 1000 / 16 + 273150; 177 break; 178 } 179 sc->bad_crc++; 180 } else 181 sc->bad_reads++; 182 } 183 mtx_lock(&sc->temp_lock); 184 msleep(sc, &sc->temp_lock, 0, "owtcvt", sc->reading_interval); 185 } 186 sc->flags &= ~OW_TEMP_RUNNING; 187 mtx_unlock(&sc->temp_lock); 188 kproc_exit(0); 189 } 190 191 static int 192 ow_temp_attach(device_t dev) 193 { 194 struct ow_temp_softc *sc; 195 196 sc = device_get_softc(dev); 197 sc->dev = dev; 198 sc->type = ow_get_family(dev); 199 SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev), 200 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 201 OID_AUTO, "temperature", 202 CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_NEEDGIANT, 203 &sc->temp, 0, sysctl_handle_int, 204 "IK3", "Current Temperature"); 205 SYSCTL_ADD_INT(device_get_sysctl_ctx(dev), 206 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 207 OID_AUTO, "badcrc", CTLFLAG_RD, 208 &sc->bad_crc, 0, 209 "Number of Bad CRC on reading scratchpad"); 210 SYSCTL_ADD_INT(device_get_sysctl_ctx(dev), 211 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 212 OID_AUTO, "badread", CTLFLAG_RD, 213 &sc->bad_reads, 0, 214 "Number of errors on reading scratchpad"); 215 SYSCTL_ADD_INT(device_get_sysctl_ctx(dev), 216 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 217 OID_AUTO, "reading_interval", CTLFLAG_RW, 218 &sc->reading_interval, 0, 219 "ticks between reads"); 220 SYSCTL_ADD_INT(device_get_sysctl_ctx(dev), 221 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 222 OID_AUTO, "parasite", CTLFLAG_RW, 223 &sc->parasite, 0, 224 "In Parasite mode"); 225 /* 226 * Just do this for unit 0 to avoid locking 227 * the ow bus until that code can be put 228 * into place. 229 */ 230 sc->temp = -1; 231 sc->reading_interval = 10 * hz; 232 mtx_init(&sc->temp_lock, "lock for doing temperature", NULL, MTX_DEF); 233 /* Start the thread */ 234 if (kproc_create(ow_temp_event_thread, sc, &sc->event_thread, 0, 0, 235 "%s event thread", device_get_nameunit(dev))) { 236 device_printf(dev, "unable to create event thread.\n"); 237 panic("ow_temp_attach, can't create thread"); 238 } 239 240 return 0; 241 } 242 243 static int 244 ow_temp_detach(device_t dev) 245 { 246 struct ow_temp_softc *sc; 247 248 sc = device_get_softc(dev); 249 250 /* 251 * Wait for the thread to die. kproc_exit will do a wakeup 252 * on the event thread's struct thread * so that we know it is 253 * safe to proceed. IF the thread is running, set the please 254 * die flag and wait for it to comply. Since the wakeup on 255 * the event thread happens only in kproc_exit, we don't 256 * need to loop here. 257 */ 258 mtx_lock(&sc->temp_lock); 259 sc->flags |= OW_TEMP_DONE; 260 while (sc->flags & OW_TEMP_RUNNING) { 261 wakeup(sc); 262 msleep(sc->event_thread, &sc->temp_lock, PWAIT, "owtun", 0); 263 } 264 mtx_destroy(&sc->temp_lock); 265 266 return 0; 267 } 268 269 devclass_t ow_temp_devclass; 270 271 static device_method_t ow_temp_methods[] = { 272 /* Device interface */ 273 DEVMETHOD(device_probe, ow_temp_probe), 274 DEVMETHOD(device_attach, ow_temp_attach), 275 DEVMETHOD(device_detach, ow_temp_detach), 276 277 { 0, 0 } 278 }; 279 280 static driver_t ow_temp_driver = { 281 "ow_temp", 282 ow_temp_methods, 283 sizeof(struct ow_temp_softc), 284 }; 285 286 DRIVER_MODULE(ow_temp, ow, ow_temp_driver, ow_temp_devclass, 0, 0); 287 MODULE_DEPEND(ow_temp, ow, 1, 1, 1); 288