adadc.c revision 1.3
1/* $NetBSD: adadc.c,v 1.3 2018/03/16 22:10:31 macallan Exp $ */ 2 3/*- 4 * Copyright (c) 2018 Michael Lorenz 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29/* 30 * a driver for Analog Devices AD7417 temperature sensors / ADCs 31 * very much macppc only for now since we need calibaration data to make sense 32 * of the ADC inputs 33 * info on how to get these from FreeBSD and Linux 34 */ 35 36#include <sys/cdefs.h> 37__KERNEL_RCSID(0, "$NetBSD: adadc.c,v 1.3 2018/03/16 22:10:31 macallan Exp $"); 38 39#include <sys/param.h> 40#include <sys/systm.h> 41#include <sys/device.h> 42#include <sys/conf.h> 43#include <sys/bus.h> 44 45#include <dev/i2c/i2cvar.h> 46 47#include <dev/sysmon/sysmonvar.h> 48 49#include <dev/ofw/openfirm.h> 50 51/* commands */ 52#define ADADC_TEMP 0x00 /* temperature, 16bit */ 53#define ADADC_CONFIG 0x01 /* 8bit */ 54#define ADADC_THYST 0x02 /* 16bit */ 55#define ADADC_TOTI 0x03 /* 16bit, temperature threshold */ 56#define ADADC_ADC 0x04 /* 16bit, ADC value */ 57#define ADADC_CONFIG2 0x05 /* 8bit */ 58 59/* 60 * registers 61 * ADADC_TEMP has signed temperature in C in first byte, left aligned fraction 62 * in 2nd byte. 63 */ 64 65#define ADADC_CFG_CHANNEL_0 0x00 66#define ADADC_CFG_CHANNEL_1 0x20 67#define ADADC_CFG_CHANNEL_2 0x40 68#define ADADC_CFG_CHANNEL_3 0x60 69#define ADADC_CFG_CHANNEL_4 0x80 70#define ADADC_CFG_CHANNEL_MASK 0xe0 71#define ADADC_CFG_FAULT_MASK 0x18 72#define ADADC_CFG_OTI_POL 0x04 /* overtemp output polarity */ 73#define ADADC_CFG_INTMODE 0x02 /* interrupt mode */ 74#define ADADC_CFG_SHUTDOWN 0x01 /* shutdown mode */ 75 76 77struct adadc_softc { 78 device_t sc_dev; 79 i2c_tag_t sc_i2c; 80 i2c_addr_t sc_addr; 81 82 struct sysmon_envsys *sc_sme; 83 envsys_data_t sc_sensors[5]; 84 int sc_nsensors; 85 int sc_diode_offset, sc_diode_slope; 86}; 87 88static int adadc_match(device_t, cfdata_t, void *); 89static void adadc_attach(device_t, device_t, void *); 90 91static void adadc_sensors_refresh(struct sysmon_envsys *, envsys_data_t *); 92 93CFATTACH_DECL_NEW(adadc, sizeof(struct adadc_softc), 94 adadc_match, adadc_attach, NULL, NULL); 95 96static const char * dstemp_compats[] = { 97 "ad7417", 98 NULL 99}; 100 101/* calibaration table from Darwin via Linux */ 102static int slope[5] = {0, 0, 0x0320, 0x00a0, 0x1f40}; 103 104static int 105adadc_match(device_t parent, cfdata_t match, void *aux) 106{ 107 struct i2c_attach_args *ia = aux; 108 109 if (ia->ia_name == NULL) { 110 /* 111 * XXX 112 * this driver is pretty much useless without OF, should 113 * probably remove this 114 */ 115 if ((ia->ia_addr & 0x2b) == 0x2b) 116 return 1; 117 return 0; 118 } else { 119 return iic_compat_match(ia, dstemp_compats); 120 } 121} 122 123static void 124adadc_attach(device_t parent, device_t self, void *aux) 125{ 126 struct adadc_softc *sc = device_private(self); 127 struct i2c_attach_args *ia = aux; 128 envsys_data_t *s; 129 int error, ch; 130 uint32_t eeprom[40]; 131 char loc[256]; 132 int which_cpu; 133 134 sc->sc_dev = self; 135 sc->sc_i2c = ia->ia_tag; 136 sc->sc_addr = ia->ia_addr; 137 138 aprint_naive("\n"); 139 aprint_normal(": AD7417\n"); 140 141 sc->sc_sme = sysmon_envsys_create(); 142 sc->sc_sme->sme_name = device_xname(self); 143 sc->sc_sme->sme_cookie = sc; 144 sc->sc_sme->sme_refresh = adadc_sensors_refresh; 145 sc->sc_nsensors = 0; 146 147 /* 148 * XXX 149 * without OpenFirmware telling us how to interpret the ADC inputs we 150 * should probably just expose the temperature and four ENVSYS_INTEGERs 151 */ 152 which_cpu = 0; 153 ch = OF_child(ia->ia_cookie); 154 while (ch != 0) { 155 if (OF_getprop(ch, "location", loc, 32) > 0) { 156 int reg = 0; 157 OF_getprop(ch, "reg", ®, sizeof(reg)); 158 s = &sc->sc_sensors[sc->sc_nsensors]; 159 /* 160 * this setup matches my 2x 2.5GHz PCI-X G5, Linux and 161 * FreeBSD hardcode these as well so we should be safe 162 */ 163 switch (reg) { 164 case 0: 165 if (strstr(loc, "CPU B") != NULL) 166 which_cpu = 1; 167 /* FALLTHROUGH */ 168 case 1: 169 s->units = ENVSYS_STEMP; 170 break; 171 case 2: 172 case 4: 173 s->units = ENVSYS_SAMPS; 174 break; 175 case 3: 176 s->units = ENVSYS_SVOLTS_DC; 177 break; 178 default: 179 s->units = ENVSYS_INTEGER; 180 } 181 strncpy(s->desc, loc, sizeof(s->desc)); 182 s->private = reg; 183 sysmon_envsys_sensor_attach(sc->sc_sme, s); 184 sc->sc_nsensors++; 185 } 186 ch = OF_peer(ch); 187 } 188 aprint_debug_dev(self, "monitoring CPU %d\n", which_cpu); 189 error = get_cpuid(which_cpu, (uint8_t *)eeprom); 190 if (error >= 0) { 191 sc->sc_diode_slope = eeprom[0x11] >> 16; 192 sc->sc_diode_offset = (int16_t)(eeprom[0x11] & 0xffff) << 12; 193 } 194 sysmon_envsys_register(sc->sc_sme); 195} 196 197static void 198adadc_sensors_refresh(struct sysmon_envsys *sme, envsys_data_t *edata) 199{ 200 struct adadc_softc *sc = sme->sme_cookie; 201 uint8_t cmd = ADADC_CONFIG; 202 int16_t data = 0; 203 uint16_t rdata; 204 uint8_t cfg; 205 int error, ch; 206 207 208 iic_acquire_bus(sc->sc_i2c, 0); 209 if (edata->private > 0) { 210 error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP, 211 sc->sc_addr, &cmd, 1, &cfg, 1, 0); 212 ch = cfg >> 5; 213 /* are we on the right channel already? */ 214 if (ch != edata->private) { 215 /* nope */ 216 cfg &= 0x1f; 217 cfg |= (edata->private & 7) << 5; 218 iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP, 219 sc->sc_addr, &cmd, 1, &cfg, 1, 0); 220 } 221 cmd = ADADC_ADC; 222 /* now read the ADC register */ 223 error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP, 224 sc->sc_addr, &cmd, 1, &rdata, 2, 0); 225 rdata = be16toh(rdata) >> 6; 226 if (edata->private == 1) { 227 int temp; 228 temp = (rdata * sc->sc_diode_slope + 229 sc->sc_diode_offset) >> 2; 230 /* 16.16 fixed point */ 231 edata->value_cur = (temp >> 12) * 62500 + 273150000; 232 } else { 233 /* 234 * the input is 10bit, so converting to 8.4 fixed point 235 * is more than enough 236 */ 237 int temp = rdata * slope[edata->private]; 238 edata->value_cur = (temp >> 12) * 62500; 239 } 240 } else { 241 cmd = ADADC_TEMP; 242 /* just read the temperature register */ 243 error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP, 244 sc->sc_addr, &cmd, 1, &data, 2, 0); 245 /* 8.2 bit fixed point Celsius -> microkelvin */ 246 edata->value_cur = ((data >> 6) * 250000) + 273150000; 247 } 248 iic_release_bus(sc->sc_i2c, 0); 249 250 if (error) { 251 edata->state = ENVSYS_SINVALID; 252 } else { 253 edata->state = ENVSYS_SVALID; 254 } 255} 256