1 /* $NetBSD: tmp121.c,v 1.7 2022/01/19 05:21:44 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 2006 Urbana-Champaign Independent Media Center.
5 * Copyright (c) 2006 Garrett D'Amore.
6 * All rights reserved.
7 *
8 * Portions of this code were written by Garrett D'Amore for the
9 * Champaign-Urbana Community Wireless Network Project.
10 *
11 * Redistribution and use in source and binary forms, with or
12 * without modification, are permitted provided that the following
13 * conditions are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above
17 * copyright notice, this list of conditions and the following
18 * disclaimer in the documentation and/or other materials provided
19 * with the distribution.
20 * 3. All advertising materials mentioning features or use of this
21 * software must display the following acknowledgements:
22 * This product includes software developed by the Urbana-Champaign
23 * Independent Media Center.
24 * This product includes software developed by Garrett D'Amore.
25 * 4. Urbana-Champaign Independent Media Center's name and Garrett
26 * D'Amore's name may not be used to endorse or promote products
27 * derived from this software without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE URBANA-CHAMPAIGN INDEPENDENT
30 * MEDIA CENTER AND GARRETT D'AMORE ``AS IS'' AND ANY EXPRESS OR
31 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
32 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33 * ARE DISCLAIMED. IN NO EVENT SHALL THE URBANA-CHAMPAIGN INDEPENDENT
34 * MEDIA CENTER OR GARRETT D'AMORE BE LIABLE FOR ANY DIRECT, INDIRECT,
35 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
37 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
38 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
40 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
41 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42 */
43
44 #include <sys/cdefs.h>
45 __KERNEL_RCSID(0, "$NetBSD: tmp121.c,v 1.7 2022/01/19 05:21:44 thorpej Exp $");
46
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/device.h>
50 #include <sys/kernel.h>
51
52 #include <dev/sysmon/sysmonvar.h>
53
54 #include <dev/spi/spivar.h>
55
56 struct tmp121temp_softc {
57 struct spi_handle *sc_sh;
58
59 struct sysmon_envsys *sc_sme;
60 envsys_data_t sc_sensor;
61 };
62
63 static int tmp121temp_match(device_t, cfdata_t, void *);
64 static void tmp121temp_attach(device_t, device_t, void *);
65
66 static void tmp121temp_refresh(struct sysmon_envsys *, envsys_data_t *);
67
68 CFATTACH_DECL_NEW(tmp121temp, sizeof(struct tmp121temp_softc),
69 tmp121temp_match, tmp121temp_attach, NULL, NULL);
70
71 static int
tmp121temp_match(device_t parent,cfdata_t cf,void * aux)72 tmp121temp_match(device_t parent, cfdata_t cf, void *aux)
73 {
74 return 1;
75 }
76
77 static void
tmp121temp_attach(device_t parent,device_t self,void * aux)78 tmp121temp_attach(device_t parent, device_t self, void *aux)
79 {
80 struct tmp121temp_softc *sc = device_private(self);
81 struct spi_attach_args *sa = aux;
82 int error;
83
84 aprint_naive(": Temperature Sensor\n");
85 aprint_normal(": TI TMP121 Temperature Sensor\n");
86
87 /* configure for 10MHz */
88 error = spi_configure(self, sa->sa_handle, SPI_MODE_0, 1000000);
89 if (error) {
90 return;
91 }
92
93 sc->sc_sh = sa->sa_handle;
94
95 sc->sc_sme = sysmon_envsys_create();
96 sc->sc_sensor.units = ENVSYS_STEMP;
97 sc->sc_sensor.state = ENVSYS_SINVALID;
98 strlcpy(sc->sc_sensor.desc, device_xname(self),
99 sizeof(sc->sc_sensor.desc));
100 if (sysmon_envsys_sensor_attach(sc->sc_sme, &sc->sc_sensor)) {
101 sysmon_envsys_destroy(sc->sc_sme);
102 return;
103 }
104
105 sc->sc_sme->sme_name = device_xname(self);
106 sc->sc_sme->sme_refresh = tmp121temp_refresh;
107 sc->sc_sme->sme_cookie = sc;
108
109 if (sysmon_envsys_register(sc->sc_sme)) {
110 aprint_error_dev(self, "unable to register with sysmon\n");
111 sysmon_envsys_destroy(sc->sc_sme);
112 }
113 }
114
115 static void
tmp121temp_refresh(struct sysmon_envsys * sme,envsys_data_t * edata)116 tmp121temp_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
117 {
118 struct tmp121temp_softc *sc = sme->sme_cookie;
119 uint16_t reg;
120 int16_t sreg;
121 int val;
122
123 if (spi_recv(sc->sc_sh, 2, (uint8_t *)®) != 0) {
124 edata->state = ENVSYS_SINVALID;
125 return;
126 }
127
128 sreg = (int16_t)be16toh(reg);
129
130 /*
131 * convert to uK:
132 *
133 * TMP121 bits:
134 * D15 : sign bit
135 * D14-D3 : data (D14 is MSB)
136 * D2-D0 : zero
137 *
138 * The data is represented in units of 0.0625 deg C.
139 */
140 sreg >>= 3;
141 val = sreg * 62500 + 273150000;
142
143 edata->value_cur = val;
144 edata->state = ENVSYS_SVALID;
145 }
146