xref: /openbsd/sys/dev/i2c/tsl2560.c (revision 471aeecf)
1 /*	$OpenBSD: tsl2560.c,v 1.8 2022/04/06 18:59:28 naddy Exp $	*/
2 
3 /*
4  * Copyright (c) 2005 Mark Kettenis
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/param.h>
20 #include <sys/systm.h>
21 #include <sys/device.h>
22 #include <sys/sensors.h>
23 
24 #include <dev/i2c/i2cvar.h>
25 
26 /* TSL2560/61 registers */
27 #define TSL2560_REG_CONTROL	0x80
28 #define  TSL2560_CONTROL_POWER	0x03
29 #define TSL2560_REG_TIMING	0x81
30 #define  TSL2560_TIMING_GAIN	0x10 /* high gain (16x) */
31 #define  TSL2560_TIMING_INTEG0	0x00 /* 13.7ms */
32 #define  TSL2560_TIMING_INTEG1	0x01 /* 101ms */
33 #define  TSL2560_TIMING_INTEG2	0x02 /* 402ms */
34 #define TSL2560_REG_ID		0x8a
35 #define TSL2560_REG_DATA0	0xac
36 #define TSL2560_REG_DATA1	0xae
37 
38 struct tsl_softc {
39 	struct device sc_dev;
40 	i2c_tag_t sc_tag;
41 	i2c_addr_t sc_addr;
42 
43 	struct ksensor sc_sensor;
44 	struct ksensordev sc_sensordev;
45 };
46 
47 int	tsl_match(struct device *, void *, void *);
48 void	tsl_attach(struct device *, struct device *, void *);
49 
50 void	tsl_refresh(void *);
51 u_int64_t tsl_lux(u_int32_t, u_int32_t);
52 
53 const struct cfattach tsl_ca = {
54 	sizeof(struct tsl_softc), tsl_match, tsl_attach
55 };
56 
57 struct cfdriver tsl_cd = {
58 	NULL, "tsl", DV_DULL
59 };
60 
61 int
tsl_match(struct device * parent,void * match,void * aux)62 tsl_match(struct device *parent, void *match, void *aux)
63 {
64 	struct i2c_attach_args *ia = aux;
65 
66 	if (strcmp(ia->ia_name, "tsl2560") == 0)
67 		return (1);
68 	return (0);
69 }
70 
71 void
tsl_attach(struct device * parent,struct device * self,void * aux)72 tsl_attach(struct device *parent, struct device *self, void *aux)
73 {
74 	struct tsl_softc *sc = (struct tsl_softc *)self;
75 	struct i2c_attach_args *ia = aux;
76 	u_int8_t cmd, data;
77 
78 	sc->sc_tag = ia->ia_tag;
79 	sc->sc_addr = ia->ia_addr;
80 
81 	iic_acquire_bus(sc->sc_tag, 0);
82 	cmd = TSL2560_REG_CONTROL; data = TSL2560_CONTROL_POWER;
83 	if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
84 	    sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
85 		iic_release_bus(sc->sc_tag, 0);
86 		printf(": power up failed\n");
87 		return;
88 	}
89 	cmd = TSL2560_REG_TIMING;
90 	data = TSL2560_TIMING_GAIN | TSL2560_TIMING_INTEG2;
91 	if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
92 	    sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
93 		iic_release_bus(sc->sc_tag, 0);
94 		printf(": cannot write timing register\n");
95 		return;
96 	}
97 	cmd = TSL2560_REG_ID;
98 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
99 	    sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
100 		iic_release_bus(sc->sc_tag, 0);
101 		printf(": cannot read ID register\n");
102 		return;
103 	}
104 	iic_release_bus(sc->sc_tag, 0);
105 
106 	switch (data >> 4) {
107 	case 0:
108 		printf(": TSL2560 rev %x", data & 0x0f);
109 		break;
110 	case 1:
111 		printf(": TSL2561 rev %x", data & 0x0f);
112 		break;
113 	default:
114 		printf(": unknown part number %x", data >> 4);
115 		break;
116 	}
117 
118 	/* Initialize sensor data. */
119 	strlcpy(sc->sc_sensordev.xname, sc->sc_dev.dv_xname,
120 	    sizeof(sc->sc_sensordev.xname));
121 	sc->sc_sensor.type = SENSOR_LUX;
122 
123 	if (sensor_task_register(sc, tsl_refresh, 5) == NULL) {
124 		printf(": unable to register update task\n");
125 		return;
126 	}
127 
128 	sensor_attach(&sc->sc_sensordev, &sc->sc_sensor);
129 	sensordev_install(&sc->sc_sensordev);
130 
131 	printf("\n");
132 }
133 
134 void
tsl_refresh(void * arg)135 tsl_refresh(void *arg)
136 {
137 	struct tsl_softc *sc = arg;
138 	u_int8_t cmd, data[2];
139 	u_int16_t chan0, chan1;
140 
141 	iic_acquire_bus(sc->sc_tag, 0);
142 	cmd = TSL2560_REG_DATA0;
143 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
144 	    sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
145 		iic_release_bus(sc->sc_tag, 0);
146 		sc->sc_sensor.flags |= SENSOR_FINVALID;
147 		return;
148 	}
149 	chan0 = data[1] << 8 | data[0];
150 	cmd = TSL2560_REG_DATA1;
151 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
152 	    sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
153 		iic_release_bus(sc->sc_tag, 0);
154 		sc->sc_sensor.flags |= SENSOR_FINVALID;
155 		return;
156 	}
157 	chan1 = data[1] << 8 | data[0];
158 	iic_release_bus(sc->sc_tag, 0);
159 
160 	sc->sc_sensor.value = tsl_lux(chan0, chan1);
161 	sc->sc_sensor.flags &= ~SENSOR_FINVALID;
162 }
163 
164 /* Precision for fixed-point math. */
165 #define TSL2560_RATIO_SCALE	9
166 #define TSL2560_LUX_SCALE	14
167 
168 /*
169  * The TSL2560/2561 comes in a ChipScale or TMB-6 package and the
170  * calibration is slightly different for each package.  The constants
171  * below are for the TMB-6 package.
172  */
173 
174 #define TSL2560_K1T	0x0040	/* 0.125 * (1 << TSL2560_RATIO_SCALE) */
175 #define TSL2560_B1T	0x01f2	/* 0.0304 * (1 << TSL2560_LUX_SCALE) */
176 #define TSL2560_M1T	0x01be	/* 0.0272 * (1 << TSL2560_LUX_SCALE) */
177 
178 #define TSL2560_K2T	0x0080	/* 0.250 * (1 << TSL2560_RATIO_SCALE) */
179 #define TSL2560_B2T	0x0214	/* 0.0324 * (1 << TSL2560_LUX_SCALE) */
180 #define TSL2560_M2T	0x02d1	/* 0.0440 * (1 << TSL2560_LUX_SCALE) */
181 
182 #define TSL2560_K3T	0x00c0	/* 0.375 * (1 << TSL2560_RATIO_SCALE) */
183 #define TSL2560_B3T	0x023f	/* 0.0351 * (1 << TSL2560_LUX_SCALE) */
184 #define TSL2560_M3T	0x037b	/* 0.0544 * (1 << TSL2560_LUX_SCALE) */
185 
186 #define TSL2560_K4T	0x0080	/* 0.50 * (1 << TSL2560_RATIO_SCALE) */
187 #define TSL2560_B4T	0x0214	/* 0.0381 * (1 << TSL2560_LUX_SCALE) */
188 #define TSL2560_M4T	0x02d1	/* 0.0624 * (1 << TSL2560_LUX_SCALE) */
189 
190 #define TSL2560_K5T	0x0138	/* 0.61 * (1 << TSL2560_RATIO_SCALE) */
191 #define TSL2560_B5T	0x016f	/* 0.0224 * (1 << TSL2560_LUX_SCALE) */
192 #define TSL2560_M5T	0x01fc	/* 0.0310 * (1 << TSL2560_LUX_SCALE) */
193 
194 #define TSL2560_K6T	0x0100	/* 0.80 * (1 << TSL2560_RATIO_SCALE) */
195 #define TSL2560_B6T	0x0270	/* 0.0128 * (1 << TSL2560_LUX_SCALE) */
196 #define TSL2560_M6T	0x03fe	/* 0.0153 * (1 << TSL2560_LUX_SCALE) */
197 
198 #define TSL2560_K7T	0x019a	/* 1.3 * (1 << TSL2560_RATIO_SCALE) */
199 #define TSL2560_B7T	0x0018	/* 0.00146 * (1 << TSL2560_LUX_SCALE) */
200 #define TSL2560_M7T	0x0012	/* 0.00112 * (1 << TSL2560_LUX_SCALE) */
201 
202 u_int64_t
tsl_lux(u_int32_t chan0,u_int32_t chan1)203 tsl_lux(u_int32_t chan0, u_int32_t chan1)
204 {
205 	u_int32_t ratio, ratio1;
206 	u_int32_t b, m;
207 	int64_t lux;
208 
209 	ratio1 = 0;
210 	if (chan0 != 0)
211 		ratio1 = (chan1 << (TSL2560_RATIO_SCALE + 1)) / chan0;
212 	ratio = (ratio1 + 1) >> 1;
213 
214 	b = 0, m = 0;
215 	if (ratio <= TSL2560_K1T)
216 		b = TSL2560_B1T, m = TSL2560_M1T;
217 	else if (ratio <= TSL2560_K2T)
218 		b = TSL2560_B2T, m = TSL2560_M2T;
219 	else if (ratio <= TSL2560_K3T)
220 		b = TSL2560_B3T, m = TSL2560_M3T;
221 	else if (ratio <= TSL2560_K4T)
222 		b = TSL2560_B4T, m = TSL2560_M4T;
223 	else if (ratio <= TSL2560_K5T)
224 		b = TSL2560_B5T, m = TSL2560_M5T;
225 	else if (ratio <= TSL2560_K6T)
226 		b = TSL2560_B6T, m = TSL2560_M6T;
227 	else if (ratio <= TSL2560_K7T)
228 		b = TSL2560_B7T, m = TSL2560_M7T;
229 
230 	lux = b * chan0 - m * chan1;
231 	if (lux < 0)
232 		lux = 0;
233 	return ((lux * 1000000) >> TSL2560_LUX_SCALE);
234 }
235