1/*- 2 * Copyright (c) 2006 Sam Leffler. All rights reserved. 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, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23 */ 24 25#include <sys/cdefs.h> 26__FBSDID("$FreeBSD$"); 27/* 28 * Analog Devices AD7418 chip sitting on the I2C bus. 29 */ 30#include <sys/param.h> 31#include <sys/systm.h> 32#include <sys/kernel.h> 33#include <sys/lock.h> 34#include <sys/module.h> 35#include <sys/bus.h> 36#include <sys/resource.h> 37#include <sys/rman.h> 38#include <sys/sysctl.h> 39#include <sys/sx.h> 40 41#include <machine/bus.h> 42#include <machine/cpu.h> 43#include <machine/cpufunc.h> 44#include <machine/frame.h> 45#include <machine/resource.h> 46#include <machine/intr.h> 47 48#include <dev/iicbus/iiconf.h> 49 50#include "iicbus_if.h" 51 52#define IIC_M_WR 0 /* write operation */ 53 54#define AD7418_ADDR 0x50 /* slave address */ 55 56#define AD7418_TEMP 0 /* Temperature Value (r/o) */ 57#define AD7418_CONF 1 /* Config Register (r/w) */ 58#define AD7418_CONF_SHUTDOWN 0x01 59#define AD7418_CONF_CHAN 0xe0 /* channel select mask */ 60#define AD7418_CHAN_TEMP 0x00 /* temperature channel */ 61#define AD7418_CHAN_VOLT 0x80 /* voltage channel */ 62#define AD7418_THYST 2 /* Thyst Setpoint (r/o) */ 63#define AD7418_TOTI 3 /* Toti Setpoint */ 64#define AD7418_VOLT 4 /* ADC aka Voltage (r/o) */ 65#define AD7418_CONF2 5 /* Config2 Register (r/w) */ 66 67struct ad7418_softc { 68 device_t sc_dev; 69 struct sx sc_lock; 70 int sc_curchan; /* current channel */ 71 int sc_curtemp; 72 int sc_curvolt; 73 int sc_lastupdate; /* in ticks */ 74}; 75 76static void ad7418_update(struct ad7418_softc *); 77static int ad7418_read_1(device_t dev, int reg); 78static int ad7418_write_1(device_t dev, int reg, int v); 79 80static int 81ad7418_probe(device_t dev) 82{ 83 /* XXX really probe? */ 84 device_set_desc(dev, "Analog Devices AD7418 ADC"); 85 return (BUS_PROBE_NOWILDCARD); 86} 87 88static int 89ad7418_sysctl_temp(SYSCTL_HANDLER_ARGS) 90{ 91 struct ad7418_softc *sc = arg1; 92 int temp; 93 94 sx_xlock(&sc->sc_lock); 95 ad7418_update(sc); 96 temp = (sc->sc_curtemp / 64) * 25; 97 sx_xunlock(&sc->sc_lock); 98 return sysctl_handle_int(oidp, &temp, 0, req); 99} 100 101static int 102ad7418_sysctl_voltage(SYSCTL_HANDLER_ARGS) 103{ 104 struct ad7418_softc *sc = arg1; 105 int volt; 106 107 sx_xlock(&sc->sc_lock); 108 ad7418_update(sc); 109 volt = (sc->sc_curvolt >> 6) * 564 / 10; 110 sx_xunlock(&sc->sc_lock); 111 return sysctl_handle_int(oidp, &volt, 0, req); 112} 113 114static int 115ad7418_attach(device_t dev) 116{ 117 struct ad7418_softc *sc = device_get_softc(dev); 118 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(dev); 119 struct sysctl_oid *tree = device_get_sysctl_tree(dev); 120 int conf; 121 122 sc->sc_dev = dev; 123 sx_init(&sc->sc_lock, "ad7418"); 124 125 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 126 "temp", CTLTYPE_INT | CTLFLAG_RD, sc, 0, 127 ad7418_sysctl_temp, "I", "operating temperature"); 128 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 129 "volt", CTLTYPE_INT | CTLFLAG_RD, sc, 0, 130 ad7418_sysctl_voltage, "I", "input voltage"); 131 132 /* enable chip if configured in shutdown mode */ 133 conf = ad7418_read_1(dev, AD7418_CONF); 134 if (conf >= 0 && (conf & AD7418_CONF_SHUTDOWN)) 135 ad7418_write_1(dev, AD7418_CONF, conf &~ AD7418_CONF_SHUTDOWN); 136 137 return (0); 138} 139 140static int 141ad7418_read_1(device_t dev, int reg) 142{ 143 uint8_t addr = reg; 144 uint8_t data[1]; 145 struct iic_msg msgs[2] = { 146 { AD7418_ADDR, IIC_M_WR, 1, &addr }, 147 { AD7418_ADDR, IIC_M_RD, 1, data }, 148 }; 149 return iicbus_transfer(dev, msgs, 2) != 0 ? -1 : data[0]; 150} 151 152static int 153ad7418_write_1(device_t dev, int reg, int v) 154{ 155 /* NB: register pointer precedes actual data */ 156 uint8_t data[2]; 157 struct iic_msg msgs[1] = { 158 { AD7418_ADDR, IIC_M_WR, 2, data }, 159 }; 160 data[0] = reg; 161 data[1] = v & 0xff; 162 return iicbus_transfer(dev, msgs, 1); 163} 164 165static void 166ad7418_set_channel(struct ad7418_softc *sc, int chan) 167{ 168 if (sc->sc_curchan == chan) 169 return; 170 ad7418_write_1(sc->sc_dev, AD7418_CONF, 171 (ad7418_read_1(sc->sc_dev, AD7418_CONF) &~ AD7418_CONF_CHAN)|chan); 172 sc->sc_curchan = chan; 173#if 0 174 /* 175 * NB: Linux driver delays here but chip data sheet 176 * says nothing and things appear to work fine w/o 177 * a delay on channel change. 178 */ 179 /* let channel change settle, 1 tick should be 'nuf (need ~1ms) */ 180 tsleep(sc, 0, "ad7418", hz/1000); 181#endif 182} 183 184static int 185ad7418_read_2(device_t dev, int reg) 186{ 187 uint8_t addr = reg; 188 uint8_t data[2]; 189 struct iic_msg msgs[2] = { 190 { AD7418_ADDR, IIC_M_WR, 1, &addr }, 191 { AD7418_ADDR, IIC_M_RD, 2, data }, 192 }; 193 /* NB: D15..D8 precede D7..D0 per data sheet (Fig 12) */ 194 return iicbus_transfer(dev, msgs, 2) != 0 ? 195 -1 : ((data[0] << 8) | data[1]); 196} 197 198static void 199ad7418_update(struct ad7418_softc *sc) 200{ 201 int v; 202 203 sx_assert(&sc->sc_lock, SA_XLOCKED); 204 /* NB: no point in updating any faster than the chip */ 205 if (ticks - sc->sc_lastupdate > hz) { 206 ad7418_set_channel(sc, AD7418_CHAN_TEMP); 207 v = ad7418_read_2(sc->sc_dev, AD7418_TEMP); 208 if (v >= 0) 209 sc->sc_curtemp = v; 210 ad7418_set_channel(sc, AD7418_CHAN_VOLT); 211 v = ad7418_read_2(sc->sc_dev, AD7418_VOLT); 212 if (v >= 0) 213 sc->sc_curvolt = v; 214 sc->sc_lastupdate = ticks; 215 } 216} 217 218static device_method_t ad7418_methods[] = { 219 DEVMETHOD(device_probe, ad7418_probe), 220 DEVMETHOD(device_attach, ad7418_attach), 221 222 DEVMETHOD_END 223}; 224 225static driver_t ad7418_driver = { 226 "ad7418", 227 ad7418_methods, 228 sizeof(struct ad7418_softc), 229}; 230static devclass_t ad7418_devclass; 231 232DRIVER_MODULE(ad7418, iicbus, ad7418_driver, ad7418_devclass, 0, 0); 233MODULE_VERSION(ad7418, 1); 234MODULE_DEPEND(ad7418, iicbus, 1, 1, 1); 235