1/*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2006 Sam Leffler. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD$"); 29/* 30 * Analog Devices AD7418 chip sitting on the I2C bus. 31 */ 32#include <sys/param.h> 33#include <sys/systm.h> 34#include <sys/kernel.h> 35#include <sys/lock.h> 36#include <sys/module.h> 37#include <sys/bus.h> 38#include <sys/sysctl.h> 39#include <sys/sx.h> 40 41#include <dev/iicbus/iiconf.h> 42 43#include "iicbus_if.h" 44 45#define IIC_M_WR 0 /* write operation */ 46 47#define AD7418_ADDR 0x50 /* slave address */ 48 49#define AD7418_TEMP 0 /* Temperature Value (r/o) */ 50#define AD7418_CONF 1 /* Config Register (r/w) */ 51#define AD7418_CONF_SHUTDOWN 0x01 52#define AD7418_CONF_CHAN 0xe0 /* channel select mask */ 53#define AD7418_CHAN_TEMP 0x00 /* temperature channel */ 54#define AD7418_CHAN_VOLT 0x80 /* voltage channel */ 55#define AD7418_THYST 2 /* Thyst Setpoint (r/o) */ 56#define AD7418_TOTI 3 /* Toti Setpoint */ 57#define AD7418_VOLT 4 /* ADC aka Voltage (r/o) */ 58#define AD7418_CONF2 5 /* Config2 Register (r/w) */ 59 60struct ad7418_softc { 61 device_t sc_dev; 62 struct sx sc_lock; 63 int sc_curchan; /* current channel */ 64 int sc_curtemp; 65 int sc_curvolt; 66 int sc_lastupdate; /* in ticks */ 67}; 68 69static void ad7418_update(struct ad7418_softc *); 70static int ad7418_read_1(device_t dev, int reg); 71static int ad7418_write_1(device_t dev, int reg, int v); 72 73static int 74ad7418_probe(device_t dev) 75{ 76 /* XXX really probe? */ 77 device_set_desc(dev, "Analog Devices AD7418 ADC"); 78 return (BUS_PROBE_NOWILDCARD); 79} 80 81static int 82ad7418_sysctl_temp(SYSCTL_HANDLER_ARGS) 83{ 84 struct ad7418_softc *sc = arg1; 85 int temp; 86 87 sx_xlock(&sc->sc_lock); 88 ad7418_update(sc); 89 temp = (sc->sc_curtemp / 64) * 25; 90 sx_xunlock(&sc->sc_lock); 91 return sysctl_handle_int(oidp, &temp, 0, req); 92} 93 94static int 95ad7418_sysctl_voltage(SYSCTL_HANDLER_ARGS) 96{ 97 struct ad7418_softc *sc = arg1; 98 int volt; 99 100 sx_xlock(&sc->sc_lock); 101 ad7418_update(sc); 102 volt = (sc->sc_curvolt >> 6) * 564 / 10; 103 sx_xunlock(&sc->sc_lock); 104 return sysctl_handle_int(oidp, &volt, 0, req); 105} 106 107static int 108ad7418_attach(device_t dev) 109{ 110 struct ad7418_softc *sc = device_get_softc(dev); 111 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(dev); 112 struct sysctl_oid *tree = device_get_sysctl_tree(dev); 113 int conf; 114 115 sc->sc_dev = dev; 116 sc->sc_lastupdate = ticks - hz; 117 118 sx_init(&sc->sc_lock, "ad7418"); 119 120 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 121 "temp", CTLTYPE_INT | CTLFLAG_RD, sc, 0, 122 ad7418_sysctl_temp, "I", "operating temperature"); 123 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 124 "volt", CTLTYPE_INT | CTLFLAG_RD, sc, 0, 125 ad7418_sysctl_voltage, "I", "input voltage"); 126 127 /* enable chip if configured in shutdown mode */ 128 conf = ad7418_read_1(dev, AD7418_CONF); 129 if (conf >= 0 && (conf & AD7418_CONF_SHUTDOWN)) 130 ad7418_write_1(dev, AD7418_CONF, conf &~ AD7418_CONF_SHUTDOWN); 131 132 return (0); 133} 134 135static int 136ad7418_read_1(device_t dev, int reg) 137{ 138 uint8_t addr = reg; 139 uint8_t data[1]; 140 struct iic_msg msgs[2] = { 141 { AD7418_ADDR, IIC_M_WR, 1, &addr }, 142 { AD7418_ADDR, IIC_M_RD, 1, data }, 143 }; 144 return iicbus_transfer(dev, msgs, 2) != 0 ? -1 : data[0]; 145} 146 147static int 148ad7418_write_1(device_t dev, int reg, int v) 149{ 150 /* NB: register pointer precedes actual data */ 151 uint8_t data[2]; 152 struct iic_msg msgs[1] = { 153 { AD7418_ADDR, IIC_M_WR, 2, data }, 154 }; 155 data[0] = reg; 156 data[1] = v & 0xff; 157 return iicbus_transfer(dev, msgs, 1); 158} 159 160static void 161ad7418_set_channel(struct ad7418_softc *sc, int chan) 162{ 163 if (sc->sc_curchan == chan) 164 return; 165 ad7418_write_1(sc->sc_dev, AD7418_CONF, 166 (ad7418_read_1(sc->sc_dev, AD7418_CONF) &~ AD7418_CONF_CHAN)|chan); 167 sc->sc_curchan = chan; 168#if 0 169 /* 170 * NB: Linux driver delays here but chip data sheet 171 * says nothing and things appear to work fine w/o 172 * a delay on channel change. 173 */ 174 /* let channel change settle, 1 tick should be 'nuf (need ~1ms) */ 175 tsleep(sc, 0, "ad7418", hz/1000); 176#endif 177} 178 179static int 180ad7418_read_2(device_t dev, int reg) 181{ 182 uint8_t addr = reg; 183 uint8_t data[2]; 184 struct iic_msg msgs[2] = { 185 { AD7418_ADDR, IIC_M_WR, 1, &addr }, 186 { AD7418_ADDR, IIC_M_RD, 2, data }, 187 }; 188 /* NB: D15..D8 precede D7..D0 per data sheet (Fig 12) */ 189 return iicbus_transfer(dev, msgs, 2) != 0 ? 190 -1 : ((data[0] << 8) | data[1]); 191} 192 193static void 194ad7418_update(struct ad7418_softc *sc) 195{ 196 int v; 197 198 sx_assert(&sc->sc_lock, SA_XLOCKED); 199 /* NB: no point in updating any faster than the chip */ 200 if (ticks - sc->sc_lastupdate > hz) { 201 ad7418_set_channel(sc, AD7418_CHAN_TEMP); 202 v = ad7418_read_2(sc->sc_dev, AD7418_TEMP); 203 if (v >= 0) 204 sc->sc_curtemp = v; 205 ad7418_set_channel(sc, AD7418_CHAN_VOLT); 206 v = ad7418_read_2(sc->sc_dev, AD7418_VOLT); 207 if (v >= 0) 208 sc->sc_curvolt = v; 209 sc->sc_lastupdate = ticks; 210 } 211} 212 213static device_method_t ad7418_methods[] = { 214 DEVMETHOD(device_probe, ad7418_probe), 215 DEVMETHOD(device_attach, ad7418_attach), 216 217 DEVMETHOD_END 218}; 219 220static driver_t ad7418_driver = { 221 "ad7418", 222 ad7418_methods, 223 sizeof(struct ad7418_softc), 224}; 225static devclass_t ad7418_devclass; 226 227DRIVER_MODULE(ad7418, iicbus, ad7418_driver, ad7418_devclass, 0, 0); 228MODULE_VERSION(ad7418, 1); 229MODULE_DEPEND(ad7418, iicbus, 1, 1, 1); 230