xref: /netbsd-src/sys/dev/i2c/pcf8563.c (revision 18f3098ca55677bef03345e9be442d445d06437b)
1 /*	$NetBSD: pcf8563.c,v 1.15 2021/01/27 02:29:48 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 1.15 2021/01/27 02:29:48 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 	{ .compat = "nxp,pcf8563" },
53 	{ .compat = "pcf8563rtc" },
54 	DEVICE_COMPAT_EOL
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
pcf8563rtc_match(device_t parent,cfdata_t cf,void * aux)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
pcf8563rtc_attach(device_t parent,device_t self,void * aux)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 	int error;
97 
98 	aprint_naive(": Real-time Clock\n");
99 	aprint_normal(": NXP PCF8563 Real-time Clock\n");
100 
101 	sc->sc_dev = self;
102 	sc->sc_tag = ia->ia_tag;
103 	sc->sc_addr = ia->ia_addr;
104 	sc->sc_todr.cookie = sc;
105 	sc->sc_todr.todr_gettime_ymdhms = pcf8563rtc_gettime;
106 	sc->sc_todr.todr_settime_ymdhms = pcf8563rtc_settime;
107 	sc->sc_todr.todr_setwen = NULL;
108 
109 	if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0) {
110 		aprint_error_dev(sc->sc_dev,
111 		    "failed to acquire bus for attach\n");
112 		return;
113 	}
114 	if ((error = iic_smbus_write_byte(sc->sc_tag, sc->sc_addr,
115 					  PCF8563_R_CS1, 0, 0)) == 0) {
116 		error = iic_smbus_write_byte(sc->sc_tag, sc->sc_addr,
117 					     PCF8563_R_CS2, 0, 0);
118 	}
119 	iic_release_bus(sc->sc_tag, 0);
120 	if (error) {
121 		aprint_error_dev(sc->sc_dev, "failed to initialize RTC\n");
122 		return;
123 	}
124 
125 #ifdef FDT
126 	fdtbus_todr_attach(self, ia->ia_cookie, &sc->sc_todr);
127 #else
128 	todr_attach(&sc->sc_todr);
129 #endif
130 }
131 
132 static int
pcf8563rtc_gettime(struct todr_chip_handle * ch,struct clock_ymdhms * dt)133 pcf8563rtc_gettime(struct todr_chip_handle *ch, struct clock_ymdhms *dt)
134 {
135 	struct pcf8563rtc_softc *sc = ch->cookie;
136 
137 	return pcf8563rtc_clock_read(sc, dt);
138 }
139 
140 static int
pcf8563rtc_settime(struct todr_chip_handle * ch,struct clock_ymdhms * dt)141 pcf8563rtc_settime(struct todr_chip_handle *ch, struct clock_ymdhms *dt)
142 {
143         struct pcf8563rtc_softc *sc = ch->cookie;
144 
145 	return pcf8563rtc_clock_write(sc, dt);
146 }
147 
148 static int
pcf8563rtc_clock_read(struct pcf8563rtc_softc * sc,struct clock_ymdhms * dt)149 pcf8563rtc_clock_read(struct pcf8563rtc_softc *sc, struct clock_ymdhms *dt)
150 {
151 	uint8_t bcd[PCF8563_NREGS];
152 	uint8_t reg = PCF8563_R_SECOND;
153 	int error;
154 
155 	if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0) {
156 		device_printf(sc->sc_dev, "acquire bus for read failed\n");
157 		return error;
158 	}
159 
160 	if ((error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
161 			      &reg, 1, &bcd[reg], PCF8563_R_YEAR - reg + 1,
162 			      0)) != 0) {
163 		iic_release_bus(sc->sc_tag, 0);
164 		device_printf(sc->sc_dev, "read failed\n");
165 		return error;
166 	}
167 
168 	iic_release_bus(sc->sc_tag, 0);
169 
170 	if (bcd[PCF8563_R_SECOND] & PCF8563_M_VL)
171 		return EIO;
172 
173 	dt->dt_sec = bcdtobin(bcd[PCF8563_R_SECOND] & PCF8563_M_SECOND);
174 	dt->dt_min = bcdtobin(bcd[PCF8563_R_MINUTE] & PCF8563_M_MINUTE);
175 	dt->dt_hour = bcdtobin(bcd[PCF8563_R_HOUR] & PCF8563_M_HOUR);
176 	dt->dt_day = bcdtobin(bcd[PCF8563_R_DAY] & PCF8563_M_DAY);
177 	dt->dt_wday = bcdtobin(bcd[PCF8563_R_WEEKDAY] & PCF8563_M_WEEKDAY);
178 	dt->dt_mon = bcdtobin(bcd[PCF8563_R_MONTH] & PCF8563_M_MONTH);
179 	dt->dt_year = 1900 +
180 	    (bcdtobin(bcd[PCF8563_R_YEAR] & PCF8563_M_YEAR) % 100);
181 	if ((bcd[PCF8563_R_MONTH] & PCF8563_M_CENTURY) == 0)
182 		dt->dt_year += 100;
183 
184 	return error;
185 }
186 
187 static int
pcf8563rtc_clock_write(struct pcf8563rtc_softc * sc,struct clock_ymdhms * dt)188 pcf8563rtc_clock_write(struct pcf8563rtc_softc *sc, struct clock_ymdhms *dt)
189 {
190 	uint8_t bcd[PCF8563_NREGS];
191 	uint8_t reg = PCF8563_R_SECOND;
192 	int error;
193 
194 	bcd[PCF8563_R_SECOND] = bintobcd(dt->dt_sec);
195 	bcd[PCF8563_R_MINUTE] = bintobcd(dt->dt_min);
196 	bcd[PCF8563_R_HOUR] = bintobcd(dt->dt_hour);
197 	bcd[PCF8563_R_DAY] = bintobcd(dt->dt_day);
198 	bcd[PCF8563_R_WEEKDAY] = bintobcd(dt->dt_wday);
199 	bcd[PCF8563_R_MONTH] = bintobcd(dt->dt_mon);
200 	bcd[PCF8563_R_YEAR] = bintobcd(dt->dt_year % 100);
201 	if (dt->dt_year < 2000)
202 		bcd[PCF8563_R_MONTH] |= PCF8563_M_CENTURY;
203 
204 	if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0) {
205 		device_printf(sc->sc_dev, "acquire bus for write failed\n");
206 		return error;
207 	}
208 
209 	if ((error = iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr, &reg, 1, &bcd[reg], PCF8563_R_YEAR - reg + 1, 0)) != 0) {
210 		iic_release_bus(sc->sc_tag, 0);
211 		device_printf(sc->sc_dev, "write failed\n");
212 		return error;
213 	}
214 
215 	iic_release_bus(sc->sc_tag, 0);
216 
217 	return error;
218 }
219