xref: /netbsd-src/sys/dev/i2c/adadc.c (revision 18f3098ca55677bef03345e9be442d445d06437b)
1 /* $NetBSD: adadc.c,v 1.10 2021/01/27 02:29:48 thorpej Exp $ */
2 
3 /*-
4  * Copyright (c) 2018 Michael Lorenz
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 /*
30  * a driver for Analog Devices AD7417 temperature sensors / ADCs
31  * very much macppc only for now since we need calibaration data to make sense
32  * of the ADC inputs
33  * info on how to get these from FreeBSD and Linux
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: adadc.c,v 1.10 2021/01/27 02:29:48 thorpej Exp $");
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/device.h>
42 #include <sys/conf.h>
43 #include <sys/bus.h>
44 
45 #include <dev/i2c/i2cvar.h>
46 
47 #include <dev/sysmon/sysmonvar.h>
48 
49 #include <dev/ofw/openfirm.h>
50 
51 /* commands */
52 #define ADADC_TEMP	0x00	/* temperature, 16bit */
53 #define ADADC_CONFIG	0x01	/* 8bit */
54 #define ADADC_THYST	0x02	/* 16bit */
55 #define ADADC_TOTI	0x03	/* 16bit, temperature threshold */
56 #define ADADC_ADC	0x04	/* 16bit, ADC value */
57 #define ADADC_CONFIG2	0x05	/* 8bit */
58 
59 /*
60  * registers
61  * ADADC_TEMP has signed temperature in C in first byte, left aligned fraction
62  * in 2nd byte.
63  */
64 
65 #define ADADC_CFG_CHANNEL_0	0x00
66 #define ADADC_CFG_CHANNEL_1	0x20
67 #define ADADC_CFG_CHANNEL_2	0x40
68 #define ADADC_CFG_CHANNEL_3	0x60
69 #define ADADC_CFG_CHANNEL_4	0x80
70 #define ADADC_CFG_CHANNEL_MASK	0xe0
71 #define ADADC_CFG_FAULT_MASK	0x18
72 #define ADADC_CFG_OTI_POL	0x04	/* overtemp output polarity */
73 #define ADADC_CFG_INTMODE	0x02	/* interrupt mode */
74 #define ADADC_CFG_SHUTDOWN	0x01	/* shutdown mode */
75 
76 
77 struct adadc_softc {
78 	device_t	sc_dev;
79 	i2c_tag_t	sc_i2c;
80 	i2c_addr_t	sc_addr;
81 
82 	struct sysmon_envsys *sc_sme;
83 	envsys_data_t	sc_sensors[5];
84 	int		sc_nsensors;
85 	int		sc_diode_offset, sc_diode_slope;
86 };
87 
88 static int	adadc_match(device_t, cfdata_t, void *);
89 static void	adadc_attach(device_t, device_t, void *);
90 
91 static void	adadc_sensors_refresh(struct sysmon_envsys *, envsys_data_t *);
92 
93 CFATTACH_DECL_NEW(adadc, sizeof(struct adadc_softc),
94     adadc_match, adadc_attach, NULL, NULL);
95 
96 static const struct device_compatible_entry compat_data[] = {
97 	{ .compat = "ad7417" },
98 	DEVICE_COMPAT_EOL
99 };
100 
101 /* calibaration table from Darwin via Linux */
102 static int slope[5] = {0, 0, 0x0320, 0x00a0, 0x1f40};
103 
104 static int
adadc_match(device_t parent,cfdata_t match,void * aux)105 adadc_match(device_t parent, cfdata_t match, void *aux)
106 {
107 	struct i2c_attach_args *ia = aux;
108 	int match_result;
109 
110 	if (iic_use_direct_match(ia, match, compat_data, &match_result))
111 		return match_result;
112 
113 	/*
114 	 * XXX
115 	 * this driver is pretty much useless without OF, should
116 	 * probably remove this
117 	 */
118 	if ((ia->ia_addr & 0x2b) == 0x2b)
119 		return I2C_MATCH_ADDRESS_ONLY;
120 
121 	return 0;
122 }
123 
124 static void
adadc_attach(device_t parent,device_t self,void * aux)125 adadc_attach(device_t parent, device_t self, void *aux)
126 {
127 	struct adadc_softc *sc = device_private(self);
128 	struct i2c_attach_args *ia = aux;
129 	envsys_data_t *s;
130 	int error, ch;
131 	uint32_t eeprom[40];
132 	char loc[256];
133 	int which_cpu;
134 
135 	sc->sc_dev = self;
136 	sc->sc_i2c = ia->ia_tag;
137 	sc->sc_addr = ia->ia_addr;
138 
139 	aprint_naive("\n");
140 	aprint_normal(": AD7417\n");
141 
142 	sc->sc_sme = sysmon_envsys_create();
143 	sc->sc_sme->sme_name = device_xname(self);
144 	sc->sc_sme->sme_cookie = sc;
145 	sc->sc_sme->sme_refresh = adadc_sensors_refresh;
146 	sc->sc_nsensors = 0;
147 
148 	/*
149 	 * XXX
150 	 * without OpenFirmware telling us how to interpret the ADC inputs we
151 	 * should probably just expose the temperature and four ENVSYS_INTEGERs
152 	 */
153 	which_cpu = 0;
154 	ch = OF_child(ia->ia_cookie);
155 	while (ch != 0) {
156 		if (OF_getprop(ch, "location", loc, 32) > 0) {
157 			int reg = 0;
158 			OF_getprop(ch, "reg", &reg, sizeof(reg));
159 			s = &sc->sc_sensors[sc->sc_nsensors];
160 			s->state = ENVSYS_SINVALID;
161 			/*
162 			 * this setup matches my 2x 2.5GHz PCI-X G5, Linux and
163 			 * FreeBSD hardcode these as well so we should be safe
164 			 */
165 			switch (reg) {
166 			case 0:
167 				if (strstr(loc, "CPU B") != NULL)
168 					which_cpu = 1;
169 				/* FALLTHROUGH */
170 			case 1:
171 				s->units = ENVSYS_STEMP;
172 				break;
173 			case 2:
174 			case 4:
175 				s->units = ENVSYS_SAMPS;
176 				break;
177 			case 3:
178 				s->units = ENVSYS_SVOLTS_DC;
179 				break;
180 			default:
181 				s->units = ENVSYS_INTEGER;
182 			}
183 			strncpy(s->desc, loc, sizeof(s->desc));
184 			s->private = reg;
185 			sysmon_envsys_sensor_attach(sc->sc_sme, s);
186 			sc->sc_nsensors++;
187 		}
188 		ch = OF_peer(ch);
189 	}
190 	aprint_debug_dev(self, "monitoring CPU %d\n", which_cpu);
191 	error = get_cpuid(which_cpu, (uint8_t *)eeprom);
192 	if (error >= 0) {
193 		sc->sc_diode_slope = eeprom[0x11] >> 16;
194 		sc->sc_diode_offset = (int16_t)(eeprom[0x11] & 0xffff) << 12;
195 	}
196 	sysmon_envsys_register(sc->sc_sme);
197 }
198 
199 static void
adadc_sensors_refresh(struct sysmon_envsys * sme,envsys_data_t * edata)200 adadc_sensors_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
201 {
202 	struct adadc_softc *sc = sme->sme_cookie;
203 	uint8_t cmd = ADADC_CONFIG;
204 	int16_t data = 0;
205 	uint16_t rdata;
206 	uint8_t cfg;
207 	int error, ch;
208 
209 
210 	iic_acquire_bus(sc->sc_i2c, 0);
211 	if (edata->private > 0) {
212 		error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
213 		    sc->sc_addr, &cmd, 1, &cfg, 1, 0);
214 		ch = cfg >> 5;
215 		/* are we on the right channel already? */
216 		if (ch != edata->private) {
217 			/* nope */
218 			cfg &= 0x1f;
219 			cfg |= (edata->private & 7) << 5;
220 			iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP,
221 			    sc->sc_addr, &cmd, 1, &cfg, 1, 0);
222 		}
223 		cmd = ADADC_ADC;
224 		/* now read the ADC register */
225 		error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
226 		    sc->sc_addr, &cmd, 1, &rdata, 2, 0);
227 		rdata = be16toh(rdata) >> 6;
228 		if (edata->private == 1) {
229 			int temp;
230 			temp = (rdata * sc->sc_diode_slope +
231 				sc->sc_diode_offset) >> 2;
232 			/* 16.16 fixed point */
233 			edata->value_cur = (temp >> 12) * 62500 + 273150000;
234 		} else {
235 			/*
236 			 * the input is 10bit, so converting to 8.4 fixed point
237 			 * is more than enough
238 			 */
239 			int temp = rdata * slope[edata->private];
240 			edata->value_cur = (temp >> 12) * 62500;
241 		}
242 	} else {
243 		cmd = ADADC_TEMP;
244 		/* just read the temperature register */
245 		error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
246 		    sc->sc_addr, &cmd, 1, &data, 2, 0);
247 		/* 8.2 bit fixed point Celsius -> microkelvin */
248 		edata->value_cur = ((data >> 6) * 250000) + 273150000;
249 	}
250 	iic_release_bus(sc->sc_i2c, 0);
251 
252 	if (error) {
253 		edata->state = ENVSYS_SINVALID;
254 	} else {
255 		edata->state = ENVSYS_SVALID;
256 	}
257 }
258