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      1 /*	$NetBSD: pcf8563.c,v 1.18 2025/09/08 13:06:16 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 #include <sys/cdefs.h>
     30 __KERNEL_RCSID(0, "$NetBSD: pcf8563.c,v 1.18 2025/09/08 13:06:16 thorpej 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 static const struct device_compatible_entry compat_data[] = {
     43 	{ .compat = "nxp,pcf8563" },
     44 	{ .compat = "pcf8563rtc" },
     45 	DEVICE_COMPAT_EOL
     46 };
     47 
     48 struct pcf8563rtc_softc {
     49 	device_t sc_dev;
     50 	i2c_tag_t sc_tag;
     51 	int sc_addr;
     52 	struct todr_chip_handle sc_todr;
     53 };
     54 
     55 static int pcf8563rtc_match(device_t, cfdata_t, void *);
     56 static void pcf8563rtc_attach(device_t, device_t, void *);
     57 
     58 CFATTACH_DECL_NEW(pcf8563rtc, sizeof(struct pcf8563rtc_softc),
     59     pcf8563rtc_match, pcf8563rtc_attach, NULL, NULL);
     60 
     61 static int pcf8563rtc_clock_read(struct pcf8563rtc_softc *, struct clock_ymdhms *);
     62 static int pcf8563rtc_clock_write(struct pcf8563rtc_softc *, struct clock_ymdhms *);
     63 static int pcf8563rtc_gettime(struct todr_chip_handle *, struct clock_ymdhms *);
     64 static int pcf8563rtc_settime(struct todr_chip_handle *, struct clock_ymdhms *);
     65 
     66 static int
     67 pcf8563rtc_match(device_t parent, cfdata_t cf, void *aux)
     68 {
     69 	struct i2c_attach_args *ia = aux;
     70 	int match_result;
     71 
     72 	if (iic_use_direct_match(ia, cf, compat_data, &match_result))
     73 		return match_result;
     74 
     75 	/* indirect config - check typical address */
     76 	if (ia->ia_addr == PCF8563_ADDR)
     77 		return I2C_MATCH_ADDRESS_ONLY;
     78 
     79 	return 0;
     80 }
     81 
     82 static void
     83 pcf8563rtc_attach(device_t parent, device_t self, void *aux)
     84 {
     85 	struct pcf8563rtc_softc *sc = device_private(self);
     86 	struct i2c_attach_args *ia = aux;
     87 	int error;
     88 
     89 	aprint_naive(": Real-time Clock\n");
     90 	aprint_normal(": NXP PCF8563 Real-time Clock\n");
     91 
     92 	sc->sc_dev = self;
     93 	sc->sc_tag = ia->ia_tag;
     94 	sc->sc_addr = ia->ia_addr;
     95 	sc->sc_todr.todr_dev = self;
     96 	sc->sc_todr.todr_gettime_ymdhms = pcf8563rtc_gettime;
     97 	sc->sc_todr.todr_settime_ymdhms = pcf8563rtc_settime;
     98 
     99 	if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0) {
    100 		aprint_error_dev(sc->sc_dev,
    101 		    "failed to acquire bus for attach\n");
    102 		return;
    103 	}
    104 	if ((error = iic_smbus_write_byte(sc->sc_tag, sc->sc_addr,
    105 					  PCF8563_R_CS1, 0, 0)) == 0) {
    106 		error = iic_smbus_write_byte(sc->sc_tag, sc->sc_addr,
    107 					     PCF8563_R_CS2, 0, 0);
    108 	}
    109 	iic_release_bus(sc->sc_tag, 0);
    110 	if (error) {
    111 		aprint_error_dev(sc->sc_dev, "failed to initialize RTC\n");
    112 		return;
    113 	}
    114 
    115 	todr_attach(&sc->sc_todr);
    116 }
    117 
    118 static int
    119 pcf8563rtc_gettime(struct todr_chip_handle *ch, struct clock_ymdhms *dt)
    120 {
    121 	struct pcf8563rtc_softc *sc = device_private(ch->todr_dev);
    122 
    123 	return pcf8563rtc_clock_read(sc, dt);
    124 }
    125 
    126 static int
    127 pcf8563rtc_settime(struct todr_chip_handle *ch, struct clock_ymdhms *dt)
    128 {
    129         struct pcf8563rtc_softc *sc = device_private(ch->todr_dev);
    130 
    131 	return pcf8563rtc_clock_write(sc, dt);
    132 }
    133 
    134 static int
    135 pcf8563rtc_clock_read(struct pcf8563rtc_softc *sc, struct clock_ymdhms *dt)
    136 {
    137 	uint8_t bcd[PCF8563_NREGS];
    138 	uint8_t reg = PCF8563_R_SECOND;
    139 	int error;
    140 
    141 	if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0) {
    142 		device_printf(sc->sc_dev, "acquire bus for read failed\n");
    143 		return error;
    144 	}
    145 
    146 	if ((error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
    147 			      &reg, 1, &bcd[reg], PCF8563_R_YEAR - reg + 1,
    148 			      0)) != 0) {
    149 		iic_release_bus(sc->sc_tag, 0);
    150 		device_printf(sc->sc_dev, "read failed\n");
    151 		return error;
    152 	}
    153 
    154 	iic_release_bus(sc->sc_tag, 0);
    155 
    156 	if (bcd[PCF8563_R_SECOND] & PCF8563_M_VL)
    157 		return EIO;
    158 
    159 	dt->dt_sec = bcdtobin(bcd[PCF8563_R_SECOND] & PCF8563_M_SECOND);
    160 	dt->dt_min = bcdtobin(bcd[PCF8563_R_MINUTE] & PCF8563_M_MINUTE);
    161 	dt->dt_hour = bcdtobin(bcd[PCF8563_R_HOUR] & PCF8563_M_HOUR);
    162 	dt->dt_day = bcdtobin(bcd[PCF8563_R_DAY] & PCF8563_M_DAY);
    163 	dt->dt_wday = bcdtobin(bcd[PCF8563_R_WEEKDAY] & PCF8563_M_WEEKDAY);
    164 	dt->dt_mon = bcdtobin(bcd[PCF8563_R_MONTH] & PCF8563_M_MONTH);
    165 	dt->dt_year = 1900 +
    166 	    (bcdtobin(bcd[PCF8563_R_YEAR] & PCF8563_M_YEAR) % 100);
    167 	if ((bcd[PCF8563_R_MONTH] & PCF8563_M_CENTURY) == 0)
    168 		dt->dt_year += 100;
    169 
    170 	return error;
    171 }
    172 
    173 static int
    174 pcf8563rtc_clock_write(struct pcf8563rtc_softc *sc, struct clock_ymdhms *dt)
    175 {
    176 	uint8_t bcd[PCF8563_NREGS];
    177 	uint8_t reg = PCF8563_R_SECOND;
    178 	int error;
    179 
    180 	bcd[PCF8563_R_SECOND] = bintobcd(dt->dt_sec);
    181 	bcd[PCF8563_R_MINUTE] = bintobcd(dt->dt_min);
    182 	bcd[PCF8563_R_HOUR] = bintobcd(dt->dt_hour);
    183 	bcd[PCF8563_R_DAY] = bintobcd(dt->dt_day);
    184 	bcd[PCF8563_R_WEEKDAY] = bintobcd(dt->dt_wday);
    185 	bcd[PCF8563_R_MONTH] = bintobcd(dt->dt_mon);
    186 	bcd[PCF8563_R_YEAR] = bintobcd(dt->dt_year % 100);
    187 	if (dt->dt_year < 2000)
    188 		bcd[PCF8563_R_MONTH] |= PCF8563_M_CENTURY;
    189 
    190 	if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0) {
    191 		device_printf(sc->sc_dev, "acquire bus for write failed\n");
    192 		return error;
    193 	}
    194 
    195 	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) {
    196 		iic_release_bus(sc->sc_tag, 0);
    197 		device_printf(sc->sc_dev, "write failed\n");
    198 		return error;
    199 	}
    200 
    201 	iic_release_bus(sc->sc_tag, 0);
    202 
    203 	return error;
    204 }
    205