1/*- 2 * SPDX-License-Identifier: BSD-2-Clause 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/* 29 * Analog Devices AD7418 chip sitting on the I2C bus. 30 */ 31#include <sys/param.h> 32#include <sys/systm.h> 33#include <sys/kernel.h> 34#include <sys/lock.h> 35#include <sys/module.h> 36#include <sys/bus.h> 37#include <sys/sysctl.h> 38#include <sys/sx.h> 39 40#include <dev/iicbus/iiconf.h> 41 42#include "iicbus_if.h" 43 44#define IIC_M_WR 0 /* write operation */ 45 46#define AD7418_ADDR 0x50 /* slave address */ 47 48#define AD7418_TEMP 0 /* Temperature Value (r/o) */ 49#define AD7418_CONF 1 /* Config Register (r/w) */ 50#define AD7418_CONF_SHUTDOWN 0x01 51#define AD7418_CONF_CHAN 0xe0 /* channel select mask */ 52#define AD7418_CHAN_TEMP 0x00 /* temperature channel */ 53#define AD7418_CHAN_VOLT 0x80 /* voltage channel */ 54#define AD7418_THYST 2 /* Thyst Setpoint (r/o) */ 55#define AD7418_TOTI 3 /* Toti Setpoint */ 56#define AD7418_VOLT 4 /* ADC aka Voltage (r/o) */ 57#define AD7418_CONF2 5 /* Config2 Register (r/w) */ 58 59struct ad7418_softc { 60 device_t sc_dev; 61 struct sx sc_lock; 62 int sc_curchan; /* current channel */ 63 int sc_curtemp; 64 int sc_curvolt; 65 int sc_lastupdate; /* in ticks */ 66}; 67 68static void ad7418_update(struct ad7418_softc *); 69static int ad7418_read_1(device_t dev, int reg); 70static int ad7418_write_1(device_t dev, int reg, int v); 71 72static int 73ad7418_probe(device_t dev) 74{ 75 /* XXX really probe? */ 76 device_set_desc(dev, "Analog Devices AD7418 ADC"); 77 return (BUS_PROBE_NOWILDCARD); 78} 79 80static int 81ad7418_sysctl_temp(SYSCTL_HANDLER_ARGS) 82{ 83 struct ad7418_softc *sc = arg1; 84 int temp; 85 86 sx_xlock(&sc->sc_lock); 87 ad7418_update(sc); 88 temp = (sc->sc_curtemp / 64) * 25; 89 sx_xunlock(&sc->sc_lock); 90 return sysctl_handle_int(oidp, &temp, 0, req); 91} 92 93static int 94ad7418_sysctl_voltage(SYSCTL_HANDLER_ARGS) 95{ 96 struct ad7418_softc *sc = arg1; 97 int volt; 98 99 sx_xlock(&sc->sc_lock); 100 ad7418_update(sc); 101 volt = (sc->sc_curvolt >> 6) * 564 / 10; 102 sx_xunlock(&sc->sc_lock); 103 return sysctl_handle_int(oidp, &volt, 0, req); 104} 105 106static int 107ad7418_attach(device_t dev) 108{ 109 struct ad7418_softc *sc = device_get_softc(dev); 110 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(dev); 111 struct sysctl_oid *tree = device_get_sysctl_tree(dev); 112 int conf; 113 114 sc->sc_dev = dev; 115 sc->sc_lastupdate = ticks - hz; 116 117 sx_init(&sc->sc_lock, "ad7418"); 118 119 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 120 "temp", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_NEEDGIANT, sc, 0, 121 ad7418_sysctl_temp, "I", "operating temperature"); 122 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 123 "volt", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_NEEDGIANT, sc, 0, 124 ad7418_sysctl_voltage, "I", "input voltage"); 125 126 /* enable chip if configured in shutdown mode */ 127 conf = ad7418_read_1(dev, AD7418_CONF); 128 if (conf >= 0 && (conf & AD7418_CONF_SHUTDOWN)) 129 ad7418_write_1(dev, AD7418_CONF, conf &~ AD7418_CONF_SHUTDOWN); 130 131 return (0); 132} 133 134static int 135ad7418_read_1(device_t dev, int reg) 136{ 137 uint8_t addr = reg; 138 uint8_t data[1]; 139 struct iic_msg msgs[2] = { 140 { AD7418_ADDR, IIC_M_WR, 1, &addr }, 141 { AD7418_ADDR, IIC_M_RD, 1, data }, 142 }; 143 return iicbus_transfer(dev, msgs, 2) != 0 ? -1 : data[0]; 144} 145 146static int 147ad7418_write_1(device_t dev, int reg, int v) 148{ 149 /* NB: register pointer precedes actual data */ 150 uint8_t data[2]; 151 struct iic_msg msgs[1] = { 152 { AD7418_ADDR, IIC_M_WR, 2, data }, 153 }; 154 data[0] = reg; 155 data[1] = v & 0xff; 156 return iicbus_transfer(dev, msgs, 1); 157} 158 159static void 160ad7418_set_channel(struct ad7418_softc *sc, int chan) 161{ 162 if (sc->sc_curchan == chan) 163 return; 164 ad7418_write_1(sc->sc_dev, AD7418_CONF, 165 (ad7418_read_1(sc->sc_dev, AD7418_CONF) &~ AD7418_CONF_CHAN)|chan); 166 sc->sc_curchan = chan; 167#if 0 168 /* 169 * NB: Linux driver delays here but chip data sheet 170 * says nothing and things appear to work fine w/o 171 * a delay on channel change. 172 */ 173 /* let channel change settle, 1 tick should be 'nuf (need ~1ms) */ 174 tsleep(sc, 0, "ad7418", hz/1000); 175#endif 176} 177 178static int 179ad7418_read_2(device_t dev, int reg) 180{ 181 uint8_t addr = reg; 182 uint8_t data[2]; 183 struct iic_msg msgs[2] = { 184 { AD7418_ADDR, IIC_M_WR, 1, &addr }, 185 { AD7418_ADDR, IIC_M_RD, 2, data }, 186 }; 187 /* NB: D15..D8 precede D7..D0 per data sheet (Fig 12) */ 188 return iicbus_transfer(dev, msgs, 2) != 0 ? 189 -1 : ((data[0] << 8) | data[1]); 190} 191 192static void 193ad7418_update(struct ad7418_softc *sc) 194{ 195 int v; 196 197 sx_assert(&sc->sc_lock, SA_XLOCKED); 198 /* NB: no point in updating any faster than the chip */ 199 if (ticks - sc->sc_lastupdate > hz) { 200 ad7418_set_channel(sc, AD7418_CHAN_TEMP); 201 v = ad7418_read_2(sc->sc_dev, AD7418_TEMP); 202 if (v >= 0) 203 sc->sc_curtemp = v; 204 ad7418_set_channel(sc, AD7418_CHAN_VOLT); 205 v = ad7418_read_2(sc->sc_dev, AD7418_VOLT); 206 if (v >= 0) 207 sc->sc_curvolt = v; 208 sc->sc_lastupdate = ticks; 209 } 210} 211 212static device_method_t ad7418_methods[] = { 213 DEVMETHOD(device_probe, ad7418_probe), 214 DEVMETHOD(device_attach, ad7418_attach), 215 216 DEVMETHOD_END 217}; 218 219static driver_t ad7418_driver = { 220 "ad7418", 221 ad7418_methods, 222 sizeof(struct ad7418_softc), 223}; 224 225DRIVER_MODULE(ad7418, iicbus, ad7418_driver, 0, 0); 226MODULE_VERSION(ad7418, 1); 227MODULE_DEPEND(ad7418, iicbus, 1, 1, 1); 228