xref: /netbsd-src/sys/dev/i2c/pcf8563.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: pcf8563.c,v 1.11 2018/06/26 06:03:57 thorpej 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 /* XXX */
30 #if defined(__arm__) || defined(__aarch64__)
31 #include "opt_fdt.h"
32 #endif
33 
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: pcf8563.c,v 1.11 2018/06/26 06:03:57 thorpej Exp $");
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/device.h>
40 #include <sys/kernel.h>
41 
42 #include <dev/clock_subr.h>
43 
44 #include <dev/i2c/i2cvar.h>
45 #include <dev/i2c/pcf8563reg.h>
46 
47 #ifdef FDT
48 #include <dev/fdt/fdtvar.h>
49 #endif
50 
51 static const struct device_compatible_entry compat_data[] = {
52 	{ "nxp,pcf8563",		0 },
53 	{ "pcf8563rtc",			0 },
54 	{ NULL,				0 }
55 };
56 
57 struct pcf8563rtc_softc {
58 	device_t sc_dev;
59 	i2c_tag_t sc_tag;
60 	int sc_addr;
61 	struct todr_chip_handle sc_todr;
62 };
63 
64 static int pcf8563rtc_match(device_t, cfdata_t, void *);
65 static void pcf8563rtc_attach(device_t, device_t, void *);
66 
67 CFATTACH_DECL_NEW(pcf8563rtc, sizeof(struct pcf8563rtc_softc),
68     pcf8563rtc_match, pcf8563rtc_attach, NULL, NULL);
69 
70 static int pcf8563rtc_clock_read(struct pcf8563rtc_softc *, struct clock_ymdhms *);
71 static int pcf8563rtc_clock_write(struct pcf8563rtc_softc *, struct clock_ymdhms *);
72 static int pcf8563rtc_gettime(struct todr_chip_handle *, struct clock_ymdhms *);
73 static int pcf8563rtc_settime(struct todr_chip_handle *, struct clock_ymdhms *);
74 
75 static int
76 pcf8563rtc_match(device_t parent, cfdata_t cf, void *aux)
77 {
78 	struct i2c_attach_args *ia = aux;
79 	int match_result;
80 
81 	if (iic_use_direct_match(ia, cf, compat_data, &match_result))
82 		return match_result;
83 
84 	/* indirect config - check typical address */
85 	if (ia->ia_addr == PCF8563_ADDR)
86 		return I2C_MATCH_ADDRESS_ONLY;
87 
88 	return 0;
89 }
90 
91 static void
92 pcf8563rtc_attach(device_t parent, device_t self, void *aux)
93 {
94 	struct pcf8563rtc_softc *sc = device_private(self);
95 	struct i2c_attach_args *ia = aux;
96 
97 	aprint_naive(": Real-time Clock\n");
98 	aprint_normal(": NXP PCF8563 Real-time Clock\n");
99 
100 	sc->sc_dev = self;
101 	sc->sc_tag = ia->ia_tag;
102 	sc->sc_addr = ia->ia_addr;
103 	sc->sc_todr.cookie = sc;
104 	sc->sc_todr.todr_gettime_ymdhms = pcf8563rtc_gettime;
105 	sc->sc_todr.todr_settime_ymdhms = pcf8563rtc_settime;
106 	sc->sc_todr.todr_setwen = NULL;
107 
108 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
109 	iic_smbus_write_byte(sc->sc_tag, sc->sc_addr, PCF8563_R_CS1, 0,
110 	    I2C_F_POLL);
111 	iic_smbus_write_byte(sc->sc_tag, sc->sc_addr, PCF8563_R_CS2, 0,
112 	    I2C_F_POLL);
113 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
114 
115 #ifdef FDT
116 	fdtbus_todr_attach(self, ia->ia_cookie, &sc->sc_todr);
117 #else
118 	todr_attach(&sc->sc_todr);
119 #endif
120 }
121 
122 static int
123 pcf8563rtc_gettime(struct todr_chip_handle *ch, struct clock_ymdhms *dt)
124 {
125 	struct pcf8563rtc_softc *sc = ch->cookie;
126 
127 	if (pcf8563rtc_clock_read(sc, dt) == 0)
128 		return -1;
129 
130 	return 0;
131 }
132 
133 static int
134 pcf8563rtc_settime(struct todr_chip_handle *ch, struct clock_ymdhms *dt)
135 {
136         struct pcf8563rtc_softc *sc = ch->cookie;
137 
138 	if (pcf8563rtc_clock_write(sc, dt) == 0)
139 		return -1;
140 
141 	return 0;
142 }
143 
144 static int
145 pcf8563rtc_clock_read(struct pcf8563rtc_softc *sc, struct clock_ymdhms *dt)
146 {
147 	uint8_t bcd[PCF8563_NREGS];
148 	uint8_t reg = PCF8563_R_SECOND;
149 	const int flags = I2C_F_POLL;
150 
151 	if (iic_acquire_bus(sc->sc_tag, flags)) {
152 		device_printf(sc->sc_dev, "acquire bus for read failed\n");
153 		return 0;
154 	}
155 
156 	if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, &reg, 1,
157 		     &bcd[reg], PCF8563_R_YEAR - reg + 1, flags)) {
158 		iic_release_bus(sc->sc_tag, flags);
159 		device_printf(sc->sc_dev, "read failed\n");
160 		return 0;
161 	}
162 
163 	iic_release_bus(sc->sc_tag, flags);
164 
165 	if (bcd[PCF8563_R_SECOND] & PCF8563_M_VL)
166 		return 0;
167 
168 	dt->dt_sec = bcdtobin(bcd[PCF8563_R_SECOND] & PCF8563_M_SECOND);
169 	dt->dt_min = bcdtobin(bcd[PCF8563_R_MINUTE] & PCF8563_M_MINUTE);
170 	dt->dt_hour = bcdtobin(bcd[PCF8563_R_HOUR] & PCF8563_M_HOUR);
171 	dt->dt_day = bcdtobin(bcd[PCF8563_R_DAY] & PCF8563_M_DAY);
172 	dt->dt_wday = bcdtobin(bcd[PCF8563_R_WEEKDAY] & PCF8563_M_WEEKDAY);
173 	dt->dt_mon = bcdtobin(bcd[PCF8563_R_MONTH] & PCF8563_M_MONTH);
174 	dt->dt_year = 1900 +
175 	    (bcdtobin(bcd[PCF8563_R_YEAR] & PCF8563_M_YEAR) % 100);
176 	if ((bcd[PCF8563_R_MONTH] & PCF8563_M_CENTURY) == 0)
177 		dt->dt_year += 100;
178 
179 	return 1;
180 }
181 
182 static int
183 pcf8563rtc_clock_write(struct pcf8563rtc_softc *sc, struct clock_ymdhms *dt)
184 {
185 	uint8_t bcd[PCF8563_NREGS];
186 	uint8_t reg = PCF8563_R_SECOND;
187 	const int flags = I2C_F_POLL;
188 
189 	bcd[PCF8563_R_SECOND] = bintobcd(dt->dt_sec);
190 	bcd[PCF8563_R_MINUTE] = bintobcd(dt->dt_min);
191 	bcd[PCF8563_R_HOUR] = bintobcd(dt->dt_hour);
192 	bcd[PCF8563_R_DAY] = bintobcd(dt->dt_day);
193 	bcd[PCF8563_R_WEEKDAY] = bintobcd(dt->dt_wday);
194 	bcd[PCF8563_R_MONTH] = bintobcd(dt->dt_mon);
195 	bcd[PCF8563_R_YEAR] = bintobcd(dt->dt_year % 100);
196 	if (dt->dt_year < 2000)
197 		bcd[PCF8563_R_MONTH] |= PCF8563_M_CENTURY;
198 
199 	if (iic_acquire_bus(sc->sc_tag, flags)) {
200 		device_printf(sc->sc_dev, "acquire bus for write failed\n");
201 		return 0;
202 	}
203 
204 	if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr, &reg, 1,
205 		     &bcd[reg], PCF8563_R_YEAR - reg + 1, flags)) {
206 		iic_release_bus(sc->sc_tag, flags);
207 		device_printf(sc->sc_dev, "write failed\n");
208 		return 0;
209 	}
210 
211 	iic_release_bus(sc->sc_tag, flags);
212 
213 	return 1;
214 }
215