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axp22x.c revision 1.5 
      1 /* $NetBSD: axp22x.c,v 1.5 2018/06/18 17:07:07 thorpej Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2014 Jared D. McNeill <jmcneill (at) invisible.ca>
      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 #include <sys/cdefs.h>
     30 __KERNEL_RCSID(0, "$NetBSD: axp22x.c,v 1.5 2018/06/18 17:07:07 thorpej Exp $");
     31 
     32 #include <sys/param.h>
     33 #include <sys/systm.h>
     34 #include <sys/device.h>
     35 #include <sys/conf.h>
     36 #include <sys/bus.h>
     37 #include <sys/kmem.h>
     38 
     39 #include <dev/i2c/i2cvar.h>
     40 
     41 #include <dev/sysmon/sysmonvar.h>
     42 
     43 static const char *compatible[] = {
     44 	"x-powers,axp221",
     45 	NULL
     46 };
     47 
     48 static const struct device_compatible_entry axp22x_compat_data[] = {
     49 	DEVICE_COMPAT_ENTRY(compatible),
     50 	DEVICE_COMPAT_TERMINATOR
     51 };
     52 
     53 #define AXP_TEMP_MON_REG	0x56	/* 2 bytes */
     54 
     55 struct axp22x_softc {
     56 	device_t	sc_dev;
     57 	i2c_tag_t	sc_i2c;
     58 	i2c_addr_t	sc_addr;
     59 
     60 	struct sysmon_envsys *sc_sme;
     61 	envsys_data_t	sc_sensor_temp;
     62 };
     63 
     64 static int	axp22x_match(device_t, cfdata_t, void *);
     65 static void	axp22x_attach(device_t, device_t, void *);
     66 
     67 static void	axp22x_sensors_refresh(struct sysmon_envsys *, envsys_data_t *);
     68 static int	axp22x_read(struct axp22x_softc *, uint8_t, uint8_t *, size_t);
     69 
     70 CFATTACH_DECL_NEW(axp22x, sizeof(struct axp22x_softc),
     71     axp22x_match, axp22x_attach, NULL, NULL);
     72 
     73 static int
     74 axp22x_match(device_t parent, cfdata_t match, void *aux)
     75 {
     76 	struct i2c_attach_args *ia = aux;
     77 	int match_result;
     78 
     79 	if (iic_use_direct_match(ia, match, axp22x_compat_data, &match_result))
     80 		return match_result;
     81 
     82 	/* This device is direct-config only. */
     83 
     84 	return 0;
     85 }
     86 
     87 static void
     88 axp22x_attach(device_t parent, device_t self, void *aux)
     89 {
     90 	struct axp22x_softc *sc = device_private(self);
     91 	struct i2c_attach_args *ia = aux;
     92 
     93 	sc->sc_dev = self;
     94 	sc->sc_i2c = ia->ia_tag;
     95 	sc->sc_addr = ia->ia_addr;
     96 
     97 	aprint_naive("\n");
     98 	aprint_normal("\n");
     99 
    100 	sc->sc_sme = sysmon_envsys_create();
    101 	sc->sc_sme->sme_name = device_xname(self);
    102 	sc->sc_sme->sme_cookie = sc;
    103 	sc->sc_sme->sme_refresh = axp22x_sensors_refresh;
    104 
    105 	sc->sc_sensor_temp.units = ENVSYS_STEMP;
    106 	sc->sc_sensor_temp.state = ENVSYS_SINVALID;
    107 	sc->sc_sensor_temp.flags = ENVSYS_FHAS_ENTROPY;
    108 	snprintf(sc->sc_sensor_temp.desc, sizeof(sc->sc_sensor_temp.desc),
    109 	    "internal temperature");
    110 	sysmon_envsys_sensor_attach(sc->sc_sme, &sc->sc_sensor_temp);
    111 
    112 	sysmon_envsys_register(sc->sc_sme);
    113 }
    114 
    115 static void
    116 axp22x_sensors_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
    117 {
    118 	struct axp22x_softc *sc = sme->sme_cookie;
    119 	uint8_t buf[2];
    120 	int error;
    121 
    122 	iic_acquire_bus(sc->sc_i2c, 0);
    123 	error = axp22x_read(sc, AXP_TEMP_MON_REG, buf, sizeof(buf));
    124 	iic_release_bus(sc->sc_i2c, 0);
    125 
    126 	if (error) {
    127 		edata->state = ENVSYS_SINVALID;
    128 	} else {
    129 		/* between -243.7C and 165.8C, step +0.1C */
    130 		edata->value_cur = (((buf[0] << 4) | (buf[1] & 0xf)) - 2437)
    131 				   * 100000 + 273150000;
    132 		edata->state = ENVSYS_SVALID;
    133 	}
    134 }
    135 
    136 static int
    137 axp22x_read(struct axp22x_softc *sc, uint8_t reg, uint8_t *val, size_t len)
    138 {
    139 	size_t i;
    140 	int error;
    141 
    142 	for (i = 0; i < len; i++) {
    143 		error = iic_smbus_read_byte(sc->sc_i2c, sc->sc_addr,
    144 		    reg + i, &val[i], 0);
    145 		if (error)
    146 			return error;
    147 	}
    148 
    149 	return 0;
    150 }
    151