xref: /netbsd-src/sys/dev/i2c/pcf8563.c (revision c2f76ff004a2cb67efe5b12d97bd3ef7fe89e18d)
1 /*	$NetBSD: pcf8563.c,v 1.2 2011/01/21 22:42:16 jakllsch Exp $	*/
2 
3 /*
4  * Copyright (c) 2011 Jonathan A. Kollasch
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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER OR
20  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
21  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
25  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
26  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: pcf8563.c,v 1.2 2011/01/21 22:42:16 jakllsch Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/device.h>
35 #include <sys/kernel.h>
36 
37 #include <dev/clock_subr.h>
38 
39 #include <dev/i2c/i2cvar.h>
40 #include <dev/i2c/pcf8563reg.h>
41 
42 struct pcf8563rtc_softc {
43 	device_t sc_dev;
44 	i2c_tag_t sc_tag;
45 	int sc_addr;
46 	struct todr_chip_handle sc_todr;
47 };
48 
49 static int pcf8563rtc_match(device_t, cfdata_t, void *);
50 static void pcf8563rtc_attach(device_t, device_t, void *);
51 
52 CFATTACH_DECL_NEW(pcf8563rtc, sizeof(struct pcf8563rtc_softc),
53     pcf8563rtc_match, pcf8563rtc_attach, NULL, NULL);
54 
55 static int pcf8563rtc_clock_read(struct pcf8563rtc_softc *, struct clock_ymdhms *);
56 static int pcf8563rtc_clock_write(struct pcf8563rtc_softc *, struct clock_ymdhms *);
57 static int pcf8563rtc_gettime(struct todr_chip_handle *, struct clock_ymdhms *);
58 static int pcf8563rtc_settime(struct todr_chip_handle *, struct clock_ymdhms *);
59 
60 static int
61 pcf8563rtc_match(device_t parent, cfdata_t cf, void *aux)
62 {
63 	struct i2c_attach_args *ia = aux;
64 
65 	if (ia->ia_addr == PCF8563_ADDR)
66 		return 1;
67 
68 	return 0;
69 }
70 
71 static void
72 pcf8563rtc_attach(device_t parent, device_t self, void *aux)
73 {
74 	struct pcf8563rtc_softc *sc = device_private(self);
75 	struct i2c_attach_args *ia = aux;
76 
77 	aprint_naive(": Real-time Clock\n");
78 	aprint_normal(": NXP PCF8563 Real-time Clock\n");
79 
80 	sc->sc_dev = self;
81 	sc->sc_tag = ia->ia_tag;
82 	sc->sc_addr = ia->ia_addr;
83 	sc->sc_todr.cookie = sc;
84 	sc->sc_todr.todr_gettime_ymdhms = pcf8563rtc_gettime;
85 	sc->sc_todr.todr_settime_ymdhms = pcf8563rtc_settime;
86 	sc->sc_todr.todr_setwen = NULL;
87 
88 	todr_attach(&sc->sc_todr);
89 }
90 
91 static int
92 pcf8563rtc_gettime(struct todr_chip_handle *ch, struct clock_ymdhms *dt)
93 {
94 	struct pcf8563rtc_softc *sc = ch->cookie;
95 
96 	if (pcf8563rtc_clock_read(sc, dt) == 0)
97 		return -1;
98 
99 	return 0;
100 }
101 
102 static int
103 pcf8563rtc_settime(struct todr_chip_handle *ch, struct clock_ymdhms *dt)
104 {
105         struct pcf8563rtc_softc *sc = ch->cookie;
106 
107 	if (pcf8563rtc_clock_write(sc, dt) == 0)
108 		return -1;
109 
110 	return 0;
111 }
112 
113 static int
114 pcf8563rtc_clock_read(struct pcf8563rtc_softc *sc, struct clock_ymdhms *dt)
115 {
116 	uint8_t bcd[PCF8563_NREGS];
117 	uint8_t reg = PCF8563_R_CS1;
118 
119 	if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL)) {
120 		device_printf(sc->sc_dev, "acquire bus for read failed\n");
121 		return 0;
122 	}
123 
124 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, &reg, 1,
125 		     &bcd[reg], PCF8563_R_YEAR - reg + 1, I2C_F_POLL)) {
126 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
127 		device_printf(sc->sc_dev, "read failed\n");
128 		return 0;
129 	}
130 
131 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
132 
133 	dt->dt_sec = FROMBCD(bcd[PCF8563_R_SECOND] & PCF8563_M_SECOND);
134 	dt->dt_min = FROMBCD(bcd[PCF8563_R_MINUTE] & PCF8563_M_MINUTE);
135 	dt->dt_hour = FROMBCD(bcd[PCF8563_R_HOUR] & PCF8563_M_HOUR);
136 	dt->dt_day = FROMBCD(bcd[PCF8563_R_DAY] & PCF8563_M_DAY);
137 	dt->dt_mon = FROMBCD(bcd[PCF8563_R_MONTH] & PCF8563_M_MONTH);
138 	dt->dt_year = FROMBCD(bcd[PCF8563_R_YEAR] & PCF8563_M_YEAR);
139 	dt->dt_year += 2000;
140 
141 	return 1;
142 }
143 
144 static int
145 pcf8563rtc_clock_write(struct pcf8563rtc_softc *sc, struct clock_ymdhms *dt)
146 {
147 	uint8_t bcd[PCF8563_NREGS];
148 	uint8_t reg = PCF8563_R_SECOND;
149 
150 	bcd[PCF8563_R_SECOND] = TOBCD(dt->dt_sec);
151 	bcd[PCF8563_R_MINUTE] = TOBCD(dt->dt_min);
152 	bcd[PCF8563_R_HOUR] = TOBCD(dt->dt_hour);
153 	bcd[PCF8563_R_DAY] = TOBCD(dt->dt_day);
154 	bcd[PCF8563_R_WEEKDAY] = TOBCD(dt->dt_wday);
155 	bcd[PCF8563_R_MONTH] = TOBCD(dt->dt_mon);
156 	bcd[PCF8563_R_YEAR] = TOBCD(dt->dt_year % 100);
157 
158 	if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL)) {
159 		device_printf(sc->sc_dev, "acquire bus for write failed\n");
160 		return 0;
161 	}
162 
163 	if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr, &reg, 1,
164 		     &bcd[reg], PCF8563_R_YEAR - reg + 1, I2C_F_POLL)) {
165 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
166 		device_printf(sc->sc_dev, "write failed\n");
167 		return 0;
168 	}
169 
170 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
171 
172 	return 1;
173 }
174