xref: /openbsd/sys/dev/i2c/pcf8563.c (revision 09467b48)
1 /*	$OpenBSD: pcf8563.c,v 1.2 2019/10/06 15:45:37 kettenis Exp $	*/
2 
3 /*
4  * Copyright (c) 2005 Kimihiro Nonaka
5  * Copyright (c) 2016, 2017 Mark Kettenis
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  * POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/device.h>
33 #include <sys/kernel.h>
34 #include <sys/fcntl.h>
35 #include <sys/uio.h>
36 #include <sys/conf.h>
37 #include <sys/event.h>
38 
39 #include <dev/clock_subr.h>
40 
41 #include <dev/i2c/i2cvar.h>
42 
43 /*
44  * PCF8563 Real-Time Clock
45  */
46 
47 #define PCF8563_ADDR		0x51	/* Fixed I2C Slave Address */
48 
49 #define PCF8563_CONTROL1	0x00
50 #define PCF8563_CONTROL2	0x01
51 #define PCF8563_SECONDS		0x02
52 #define PCF8563_MINUTES		0x03
53 #define PCF8563_HOURS		0x04
54 #define PCF8563_DAY		0x05
55 #define PCF8563_WDAY		0x06
56 #define PCF8563_MONTH		0x07
57 #define PCF8563_YEAR		0x08
58 
59 #define PCF8563_NREGS		12
60 #define PCF8563_NRTC_REGS	7
61 
62 /*
63  * Bit definitions.
64  */
65 #define PCF8563_CONTROL1_TESTC	(1 << 3)
66 #define PCF8563_CONTROL1_STOP	(1 << 5)
67 #define PCF8563_CONTROL1_TEST1	(1 << 1)
68 #define PCF8563_SECONDS_MASK	0x7f
69 #define PCF8563_SECONDS_VL	(1 << 7)
70 #define PCF8563_MINUTES_MASK	0x7f
71 #define PCF8563_HOURS_MASK	0x3f
72 #define PCF8563_DAY_MASK	0x3f
73 #define PCF8563_WDAY_MASK	0x07
74 #define PCF8563_MONTH_MASK	0x1f
75 #define PCF8563_MONTH_C		(1 << 7)
76 
77 struct pcxrtc_softc {
78 	struct device sc_dev;
79 	i2c_tag_t sc_tag;
80 	int sc_address;
81 	struct todr_chip_handle sc_todr;
82 };
83 
84 int pcxrtc_match(struct device *, void *, void *);
85 void pcxrtc_attach(struct device *, struct device *, void *);
86 
87 struct cfattach pcxrtc_ca = {
88 	sizeof(struct pcxrtc_softc), pcxrtc_match, pcxrtc_attach
89 };
90 
91 struct cfdriver pcxrtc_cd = {
92 	NULL, "pcxrtc", DV_DULL
93 };
94 
95 uint8_t pcxrtc_reg_read(struct pcxrtc_softc *, int);
96 void pcxrtc_reg_write(struct pcxrtc_softc *, int, uint8_t);
97 int pcxrtc_clock_read(struct pcxrtc_softc *, struct clock_ymdhms *);
98 int pcxrtc_clock_write(struct pcxrtc_softc *, struct clock_ymdhms *);
99 int pcxrtc_gettime(struct todr_chip_handle *, struct timeval *);
100 int pcxrtc_settime(struct todr_chip_handle *, struct timeval *);
101 int pcxrtc_getcal(struct todr_chip_handle *, int *);
102 int pcxrtc_setcal(struct todr_chip_handle *, int);
103 
104 int
105 pcxrtc_match(struct device *parent, void *v, void *arg)
106 {
107 	struct i2c_attach_args *ia = arg;
108 
109 	if (strcmp(ia->ia_name, "nxp,pcf8563") == 0 &&
110 	    ia->ia_addr == PCF8563_ADDR)
111 		return (1);
112 
113 	return (0);
114 }
115 
116 void
117 pcxrtc_attach(struct device *parent, struct device *self, void *arg)
118 {
119 	struct pcxrtc_softc *sc = (struct pcxrtc_softc *)self;
120 	struct i2c_attach_args *ia = arg;
121 	uint8_t reg;
122 
123 	sc->sc_tag = ia->ia_tag;
124 	sc->sc_address = ia->ia_addr;
125 	sc->sc_todr.cookie = sc;
126 	sc->sc_todr.todr_gettime = pcxrtc_gettime;
127 	sc->sc_todr.todr_settime = pcxrtc_settime;
128 	sc->sc_todr.todr_getcal = pcxrtc_getcal;
129 	sc->sc_todr.todr_setcal = pcxrtc_setcal;
130 	sc->sc_todr.todr_setwen = NULL;
131 
132 #if 0
133 	todr_attach(&sc->sc_todr);
134 #else
135 	/* XXX */
136 	{
137 	extern todr_chip_handle_t todr_handle;
138 	todr_handle = &sc->sc_todr;
139 	}
140 #endif
141 
142 	/* Enable. */
143 	reg = pcxrtc_reg_read(sc, PCF8563_CONTROL1);
144 	reg &= ~PCF8563_CONTROL1_STOP;
145 	pcxrtc_reg_write(sc, PCF8563_CONTROL1, reg);
146 
147 	/* Report battery status. */
148 	reg = pcxrtc_reg_read(sc, PCF8563_SECONDS);
149 	printf(": battery %s\n", (reg & PCF8563_SECONDS_VL) ? "low" : "ok");
150 }
151 
152 int
153 pcxrtc_gettime(struct todr_chip_handle *ch, struct timeval *tv)
154 {
155 	struct pcxrtc_softc *sc = ch->cookie;
156 	struct clock_ymdhms dt;
157 
158 	memset(&dt, 0, sizeof(dt));
159 	if (pcxrtc_clock_read(sc, &dt) == 0)
160 		return (-1);
161 
162 	tv->tv_sec = clock_ymdhms_to_secs(&dt);
163 	tv->tv_usec = 0;
164 	return (0);
165 }
166 
167 int
168 pcxrtc_settime(struct todr_chip_handle *ch, struct timeval *tv)
169 {
170 	struct pcxrtc_softc *sc = ch->cookie;
171 	struct clock_ymdhms dt;
172 
173 	clock_secs_to_ymdhms(tv->tv_sec, &dt);
174 
175 	if (pcxrtc_clock_write(sc, &dt) == 0)
176 		return (-1);
177 	return (0);
178 }
179 
180 int
181 pcxrtc_setcal(struct todr_chip_handle *ch, int cal)
182 {
183 	return (EOPNOTSUPP);
184 }
185 
186 int
187 pcxrtc_getcal(struct todr_chip_handle *ch, int *cal)
188 {
189 	return (EOPNOTSUPP);
190 }
191 
192 uint8_t
193 pcxrtc_reg_read(struct pcxrtc_softc *sc, int reg)
194 {
195 	uint8_t cmd = reg;
196 	uint8_t val;
197 
198 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
199 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_address,
200 	    &cmd, sizeof cmd, &val, sizeof val, I2C_F_POLL)) {
201 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
202 		printf("%s: pcxrtc_reg_read: failed to read reg%d\n",
203 		    sc->sc_dev.dv_xname, reg);
204 		return 0;
205 	}
206 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
207 	return val;
208 }
209 
210 void
211 pcxrtc_reg_write(struct pcxrtc_softc *sc, int reg, uint8_t val)
212 {
213 	uint8_t cmd = reg;
214 
215 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
216 	if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_address,
217 	    &cmd, sizeof cmd, &val, sizeof val, I2C_F_POLL)) {
218 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
219 		printf("%s: pcxrtc_reg_write: failed to write reg%d\n",
220 		    sc->sc_dev.dv_xname, reg);
221 		return;
222 	}
223 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
224 }
225 
226 int
227 pcxrtc_clock_read(struct pcxrtc_softc *sc, struct clock_ymdhms *dt)
228 {
229 	uint8_t regs[PCF8563_NRTC_REGS];
230 	uint8_t cmd = PCF8563_SECONDS;
231 
232 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
233 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_address,
234 	    &cmd, sizeof(cmd), regs, PCF8563_NRTC_REGS, I2C_F_POLL)) {
235 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
236 		printf("%s: pcxrtc_clock_read: failed to read rtc\n",
237 		    sc->sc_dev.dv_xname);
238 		return (0);
239 	}
240 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
241 
242 	/*
243 	 * Convert the PCF8563's register values into something useable
244 	 */
245 	dt->dt_sec = FROMBCD(regs[0] & PCF8563_SECONDS_MASK);
246 	dt->dt_min = FROMBCD(regs[1] & PCF8563_MINUTES_MASK);
247 	dt->dt_hour = FROMBCD(regs[2] & PCF8563_HOURS_MASK);
248 	dt->dt_day = FROMBCD(regs[3] & PCF8563_DAY_MASK);
249 	dt->dt_mon = FROMBCD(regs[5] & PCF8563_MONTH_MASK);
250 	dt->dt_year = FROMBCD(regs[6]) + 2000;
251 
252 	if ((regs[0] & PCF8563_SECONDS_VL))
253 		return (0);
254 
255 	return (1);
256 }
257 
258 int
259 pcxrtc_clock_write(struct pcxrtc_softc *sc, struct clock_ymdhms *dt)
260 {
261 	uint8_t regs[PCF8563_NRTC_REGS];
262 	uint8_t cmd = PCF8563_SECONDS;
263 
264 	/*
265 	 * Convert our time representation into something the PCF8563
266 	 * can understand.
267 	 */
268 	regs[0] = TOBCD(dt->dt_sec);
269 	regs[1] = TOBCD(dt->dt_min);
270 	regs[2] = TOBCD(dt->dt_hour);
271 	regs[3] = TOBCD(dt->dt_day);
272 	regs[4] = TOBCD(dt->dt_wday);
273 	regs[5] = TOBCD(dt->dt_mon);
274 	regs[6] = TOBCD(dt->dt_year - 2000);
275 
276 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
277 	if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_address,
278 	    &cmd, sizeof(cmd), regs, PCF8563_NRTC_REGS, I2C_F_POLL)) {
279 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
280 		printf("%s: pcxrtc_clock_write: failed to write rtc\n",
281 		    sc->sc_dev.dv_xname);
282 		return (0);
283 	}
284 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
285 	return (1);
286 }
287