xref: /openbsd/sys/dev/i2c/pcf8563.c (revision 0701a158)
1 /*	$OpenBSD: pcf8563.c,v 1.7 2022/10/12 13:39:50 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 
34 #include <dev/clock_subr.h>
35 
36 #include <dev/i2c/i2cvar.h>
37 
38 /*
39  * PCF8563 Real-Time Clock
40  */
41 
42 #define PCF8563_CONTROL1	0x00
43 #define PCF8563_CONTROL2	0x01
44 #define PCF8563_SECONDS		0x02
45 #define PCF8563_MINUTES		0x03
46 #define PCF8563_HOURS		0x04
47 #define PCF8563_DAY		0x05
48 #define PCF8563_WDAY		0x06
49 #define PCF8563_MONTH		0x07
50 #define PCF8563_YEAR		0x08
51 
52 #define PCF8563_NREGS		12
53 #define PCF8563_NRTC_REGS	7
54 
55 /*
56  * Bit definitions.
57  */
58 #define PCF8563_CONTROL1_TESTC	(1 << 3)
59 #define PCF8563_CONTROL1_STOP	(1 << 5)
60 #define PCF8563_CONTROL1_TEST1	(1 << 1)
61 #define PCF8563_SECONDS_MASK	0x7f
62 #define PCF8563_SECONDS_VL	(1 << 7)
63 #define PCF8563_MINUTES_MASK	0x7f
64 #define PCF8563_HOURS_MASK	0x3f
65 #define PCF8563_DAY_MASK	0x3f
66 #define PCF8563_WDAY_MASK	0x07
67 #define PCF8563_MONTH_MASK	0x1f
68 #define PCF8563_MONTH_C		(1 << 7)
69 
70 struct pcxrtc_softc {
71 	struct device sc_dev;
72 	i2c_tag_t sc_tag;
73 	int sc_address;
74 	struct todr_chip_handle sc_todr;
75 };
76 
77 int pcxrtc_match(struct device *, void *, void *);
78 void pcxrtc_attach(struct device *, struct device *, void *);
79 
80 const struct cfattach pcxrtc_ca = {
81 	sizeof(struct pcxrtc_softc), pcxrtc_match, pcxrtc_attach
82 };
83 
84 struct cfdriver pcxrtc_cd = {
85 	NULL, "pcxrtc", DV_DULL
86 };
87 
88 uint8_t pcxrtc_reg_read(struct pcxrtc_softc *, int);
89 void pcxrtc_reg_write(struct pcxrtc_softc *, int, uint8_t);
90 int pcxrtc_clock_read(struct pcxrtc_softc *, struct clock_ymdhms *);
91 int pcxrtc_clock_write(struct pcxrtc_softc *, struct clock_ymdhms *);
92 int pcxrtc_gettime(struct todr_chip_handle *, struct timeval *);
93 int pcxrtc_settime(struct todr_chip_handle *, struct timeval *);
94 
95 int
pcxrtc_match(struct device * parent,void * v,void * arg)96 pcxrtc_match(struct device *parent, void *v, void *arg)
97 {
98 	struct i2c_attach_args *ia = arg;
99 
100 	if (strcmp(ia->ia_name, "nxp,pcf8563") == 0 ||
101 	    strcmp(ia->ia_name, "haoyu,hym8563") == 0)
102 		return (1);
103 
104 	return (0);
105 }
106 
107 void
pcxrtc_attach(struct device * parent,struct device * self,void * arg)108 pcxrtc_attach(struct device *parent, struct device *self, void *arg)
109 {
110 	struct pcxrtc_softc *sc = (struct pcxrtc_softc *)self;
111 	struct i2c_attach_args *ia = arg;
112 	uint8_t reg;
113 
114 	sc->sc_tag = ia->ia_tag;
115 	sc->sc_address = ia->ia_addr;
116 
117 	sc->sc_todr.cookie = sc;
118 	sc->sc_todr.todr_gettime = pcxrtc_gettime;
119 	sc->sc_todr.todr_settime = pcxrtc_settime;
120 	sc->sc_todr.todr_setwen = NULL;
121 	sc->sc_todr.todr_quality = 1000;
122 	todr_attach(&sc->sc_todr);
123 
124 	/* Enable. */
125 	reg = pcxrtc_reg_read(sc, PCF8563_CONTROL1);
126 	reg &= ~PCF8563_CONTROL1_STOP;
127 	pcxrtc_reg_write(sc, PCF8563_CONTROL1, reg);
128 
129 	/* Report battery status. */
130 	reg = pcxrtc_reg_read(sc, PCF8563_SECONDS);
131 	printf(": battery %s\n", (reg & PCF8563_SECONDS_VL) ? "low" : "ok");
132 }
133 
134 int
pcxrtc_gettime(struct todr_chip_handle * ch,struct timeval * tv)135 pcxrtc_gettime(struct todr_chip_handle *ch, struct timeval *tv)
136 {
137 	struct pcxrtc_softc *sc = ch->cookie;
138 	struct clock_ymdhms dt;
139 
140 	memset(&dt, 0, sizeof(dt));
141 	if (pcxrtc_clock_read(sc, &dt) == 0)
142 		return (-1);
143 
144 	tv->tv_sec = clock_ymdhms_to_secs(&dt);
145 	tv->tv_usec = 0;
146 	return (0);
147 }
148 
149 int
pcxrtc_settime(struct todr_chip_handle * ch,struct timeval * tv)150 pcxrtc_settime(struct todr_chip_handle *ch, struct timeval *tv)
151 {
152 	struct pcxrtc_softc *sc = ch->cookie;
153 	struct clock_ymdhms dt;
154 
155 	clock_secs_to_ymdhms(tv->tv_sec, &dt);
156 
157 	if (pcxrtc_clock_write(sc, &dt) == 0)
158 		return (-1);
159 	return (0);
160 }
161 
162 uint8_t
pcxrtc_reg_read(struct pcxrtc_softc * sc,int reg)163 pcxrtc_reg_read(struct pcxrtc_softc *sc, int reg)
164 {
165 	uint8_t cmd = reg;
166 	uint8_t val;
167 
168 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
169 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_address,
170 	    &cmd, sizeof cmd, &val, sizeof val, I2C_F_POLL)) {
171 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
172 		printf("%s: pcxrtc_reg_read: failed to read reg%d\n",
173 		    sc->sc_dev.dv_xname, reg);
174 		return 0;
175 	}
176 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
177 	return val;
178 }
179 
180 void
pcxrtc_reg_write(struct pcxrtc_softc * sc,int reg,uint8_t val)181 pcxrtc_reg_write(struct pcxrtc_softc *sc, int reg, uint8_t val)
182 {
183 	uint8_t cmd = reg;
184 
185 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
186 	if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_address,
187 	    &cmd, sizeof cmd, &val, sizeof val, I2C_F_POLL)) {
188 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
189 		printf("%s: pcxrtc_reg_write: failed to write reg%d\n",
190 		    sc->sc_dev.dv_xname, reg);
191 		return;
192 	}
193 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
194 }
195 
196 int
pcxrtc_clock_read(struct pcxrtc_softc * sc,struct clock_ymdhms * dt)197 pcxrtc_clock_read(struct pcxrtc_softc *sc, struct clock_ymdhms *dt)
198 {
199 	uint8_t regs[PCF8563_NRTC_REGS];
200 	uint8_t cmd = PCF8563_SECONDS;
201 
202 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
203 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_address,
204 	    &cmd, sizeof(cmd), regs, PCF8563_NRTC_REGS, I2C_F_POLL)) {
205 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
206 		printf("%s: pcxrtc_clock_read: failed to read rtc\n",
207 		    sc->sc_dev.dv_xname);
208 		return (0);
209 	}
210 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
211 
212 	/*
213 	 * Convert the PCF8563's register values into something useable
214 	 */
215 	dt->dt_sec = FROMBCD(regs[0] & PCF8563_SECONDS_MASK);
216 	dt->dt_min = FROMBCD(regs[1] & PCF8563_MINUTES_MASK);
217 	dt->dt_hour = FROMBCD(regs[2] & PCF8563_HOURS_MASK);
218 	dt->dt_day = FROMBCD(regs[3] & PCF8563_DAY_MASK);
219 	dt->dt_mon = FROMBCD(regs[5] & PCF8563_MONTH_MASK);
220 	dt->dt_year = FROMBCD(regs[6]) + 2000;
221 
222 	if ((regs[0] & PCF8563_SECONDS_VL))
223 		return (0);
224 
225 	return (1);
226 }
227 
228 int
pcxrtc_clock_write(struct pcxrtc_softc * sc,struct clock_ymdhms * dt)229 pcxrtc_clock_write(struct pcxrtc_softc *sc, struct clock_ymdhms *dt)
230 {
231 	uint8_t regs[PCF8563_NRTC_REGS];
232 	uint8_t cmd = PCF8563_SECONDS;
233 
234 	/*
235 	 * Convert our time representation into something the PCF8563
236 	 * can understand.
237 	 */
238 	regs[0] = TOBCD(dt->dt_sec);
239 	regs[1] = TOBCD(dt->dt_min);
240 	regs[2] = TOBCD(dt->dt_hour);
241 	regs[3] = TOBCD(dt->dt_day);
242 	regs[4] = TOBCD(dt->dt_wday);
243 	regs[5] = TOBCD(dt->dt_mon);
244 	regs[6] = TOBCD(dt->dt_year - 2000);
245 
246 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
247 	if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_address,
248 	    &cmd, sizeof(cmd), regs, PCF8563_NRTC_REGS, I2C_F_POLL)) {
249 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
250 		printf("%s: pcxrtc_clock_write: failed to write rtc\n",
251 		    sc->sc_dev.dv_xname);
252 		return (0);
253 	}
254 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
255 	return (1);
256 }
257