xref: /openbsd/sys/dev/i2c/tmp451.c (revision 471aeecf)
1 /*	$OpenBSD: tmp451.c,v 1.2 2022/04/06 18:59:28 naddy Exp $	*/
2 /*
3  * Copyright (c) 2018 Mark Kettenis <kettenis@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/param.h>
19 #include <sys/systm.h>
20 #include <sys/device.h>
21 #include <sys/sensors.h>
22 
23 #include <dev/i2c/i2cvar.h>
24 
25 /* TI TMP451 registers */
26 #define TMP451_LT_HI		0x00
27 #define TMP451_RT_HI		0x01
28 #define TMP451_RT_LO		0x10
29 #define TMP451_RTOS_HI		0x11
30 #define TMP451_RTOS_LO		0x12
31 #define TMP451_LT_LO		0x15
32 
33 /* Sensors */
34 #define TITMP_LT		0
35 #define TITMP_RT		1
36 #define TITMP_NUM_SENSORS	2
37 
38 struct titmp_softc {
39 	struct device sc_dev;
40 	i2c_tag_t sc_tag;
41 	i2c_addr_t sc_addr;
42 
43 	uint64_t sc_offset[TITMP_NUM_SENSORS];
44 	struct ksensor sc_sensor[TITMP_NUM_SENSORS];
45 	struct ksensordev sc_sensordev;
46 };
47 
48 int	titmp_match(struct device *, void *, void *);
49 void	titmp_attach(struct device *, struct device *, void *);
50 
51 const struct cfattach titmp_ca = {
52 	sizeof(struct titmp_softc), titmp_match, titmp_attach
53 };
54 
55 struct cfdriver titmp_cd = {
56 	NULL, "titmp", DV_DULL
57 };
58 
59 void	titmp_read_offsets(struct titmp_softc *);
60 void	titmp_refresh_sensors(void *);
61 
62 int
titmp_match(struct device * parent,void * match,void * aux)63 titmp_match(struct device *parent, void *match, void *aux)
64 {
65 	struct i2c_attach_args *ia = aux;
66 
67 	return (strcmp(ia->ia_name, "ti,tmp451") == 0);
68 }
69 
70 void
titmp_attach(struct device * parent,struct device * self,void * aux)71 titmp_attach(struct device *parent, struct device *self, void *aux)
72 {
73 	struct titmp_softc *sc = (struct titmp_softc *)self;
74 	struct i2c_attach_args *ia = aux;
75 	int i;
76 
77 	sc->sc_tag = ia->ia_tag;
78 	sc->sc_addr = ia->ia_addr;
79 
80 	printf("\n");
81 
82 	titmp_read_offsets(sc);
83 
84 	/* Register sensors. */
85 	strlcpy(sc->sc_sensordev.xname, sc->sc_dev.dv_xname,
86 	    sizeof(sc->sc_sensordev.xname));
87 	sc->sc_sensor[TITMP_LT].type = SENSOR_TEMP;
88 	strlcpy(sc->sc_sensor[TITMP_LT].desc, "Local",
89 	    sizeof(sc->sc_sensor[TITMP_LT].desc));
90 	sc->sc_sensor[TITMP_RT].type = SENSOR_TEMP;
91 	strlcpy(sc->sc_sensor[TITMP_RT].desc, "Remote",
92 	    sizeof(sc->sc_sensor[TITMP_RT].desc));
93 	for (i = 0; i < TITMP_NUM_SENSORS; i++)
94 		sensor_attach(&sc->sc_sensordev, &sc->sc_sensor[i]);
95 	sensordev_install(&sc->sc_sensordev);
96 	sensor_task_register(sc, titmp_refresh_sensors, 5);
97 }
98 
99 void
titmp_read_offsets(struct titmp_softc * sc)100 titmp_read_offsets(struct titmp_softc *sc)
101 {
102 	uint8_t cmd, hi, lo;
103 	int error;
104 
105 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
106 
107 	cmd = TMP451_RTOS_HI;
108 	error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
109 	    &cmd, sizeof(cmd), &hi, sizeof(hi), I2C_F_POLL);
110 	if (error)
111 		goto fail;
112 	cmd = TMP451_RTOS_LO;
113 	error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
114 	    &cmd, sizeof(cmd), &lo, sizeof(lo), I2C_F_POLL);
115 	if (error)
116 		goto fail;
117 
118 	sc->sc_offset[TITMP_RT] = 1000000 * hi + (lo >> 4) * 1000000 / 16;
119 
120 fail:
121 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
122 }
123 
124 void
titmp_read_sensor(struct titmp_softc * sc,uint8_t cmdhi,uint8_t cmdlo,int index)125 titmp_read_sensor(struct titmp_softc *sc, uint8_t cmdhi, uint8_t cmdlo,
126     int index)
127 {
128 	uint8_t hi, lo;
129 
130 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
131 	    sc->sc_addr, &cmdhi, sizeof(cmdhi), &hi, sizeof(hi), 0))
132 		goto invalid;
133 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
134 	    sc->sc_addr, &cmdlo, sizeof(cmdlo), &lo, sizeof(lo), 0))
135 		goto invalid;
136 
137 	sc->sc_sensor[index].value = 273150000 +
138 	    1000000 * hi + (lo >> 4) * 1000000 / 16;
139 	sc->sc_sensor[index].value += sc->sc_offset[index];
140 	return;
141 
142 invalid:
143 	sc->sc_sensor[index].flags |= SENSOR_FINVALID;
144 }
145 
146 void
titmp_refresh_sensors(void * arg)147 titmp_refresh_sensors(void *arg)
148 {
149 	struct titmp_softc *sc = arg;
150 
151 	iic_acquire_bus(sc->sc_tag, 0);
152 
153 	titmp_read_sensor(sc, TMP451_LT_HI, TMP451_LT_LO, TITMP_LT);
154 	titmp_read_sensor(sc, TMP451_RT_HI, TMP451_RT_LO, TITMP_RT);
155 
156 	iic_release_bus(sc->sc_tag, 0);
157 }
158