/* $OpenBSD: pcf8523.c,v 1.3 2016/05/20 20:33:53 kettenis Exp $ */
/*
* Copyright (c) 2005 Kimihiro Nonaka
* Copyright (c) 2016 Mark Kettenis
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/kernel.h>
#include <sys/fcntl.h>
#include <sys/uio.h>
#include <sys/conf.h>
#include <sys/event.h>
#include <dev/clock_subr.h>
#include <dev/i2c/i2cvar.h>
/*
* PCF8523 Real-Time Clock
*/
#define PCF8523_ADDR 0x68 /* Fixed I2C Slave Address */
#define PCF8523_CONTROL1 0x00
#define PCF8523_CONTROL2 0x01
#define PCF8523_CONTROL3 0x02
#define PCF8523_SECONDS 0x03
#define PCF8523_MINUTES 0x04
#define PCF8523_HOURS 0x05
#define PCF8523_DAY 0x06
#define PCF8523_WDAY 0x07
#define PCF8523_MONTH 0x08
#define PCF8523_YEAR 0x09
#define PCF8523_ALARM_MIN 0x0a
#define PCF8523_ALARM_HOUR 0x0b
#define PCF8523_ALARM_DAY 0x0c
#define PCF8523_ALARM_WDAY 0x0d
#define PCF8523_OFFSET 0x0e
#define PCF8523_NREGS 20
#define PCF8523_NRTC_REGS 7
/*
* Bit definitions.
*/
#define PCF8523_CONTROL1_12_24 (1 << 3)
#define PCF8523_CONTROL1_STOP (1 << 5)
#define PCF8523_CONTROL3_PM_MASK 0xe0
#define PCF8523_CONTROL3_PM_BLD (1 << 7)
#define PCF8523_CONTROL3_PM_VDD (1 << 6)
#define PCF8523_CONTROL3_PM_DSM (1 << 5)
#define PCF8523_CONTROL3_BLF (1 << 2)
#define PCF8523_SECONDS_MASK 0x7f
#define PCF8523_SECONDS_OS (1 << 7)
#define PCF8523_MINUTES_MASK 0x7f
#define PCF8523_HOURS_12HRS_PM (1 << 5) /* If 12 hr mode, set = PM */
#define PCF8523_HOURS_12MASK 0x1f
#define PCF8523_HOURS_24MASK 0x3f
#define PCF8523_DAY_MASK 0x3f
#define PCF8523_WDAY_MASK 0x07
#define PCF8523_MONTH_MASK 0x1f
struct pcfrtc_softc {
struct device sc_dev;
i2c_tag_t sc_tag;
int sc_address;
struct todr_chip_handle sc_todr;
};
int pcfrtc_match(struct device *, void *, void *);
void pcfrtc_attach(struct device *, struct device *, void *);
struct cfattach pcfrtc_ca = {
sizeof(struct pcfrtc_softc), pcfrtc_match, pcfrtc_attach
};
struct cfdriver pcfrtc_cd = {
NULL, "pcfrtc", DV_DULL
};
uint8_t pcfrtc_reg_read(struct pcfrtc_softc *, int);
void pcfrtc_reg_write(struct pcfrtc_softc *, int, uint8_t);
int pcfrtc_clock_read(struct pcfrtc_softc *, struct clock_ymdhms *);
int pcfrtc_clock_write(struct pcfrtc_softc *, struct clock_ymdhms *);
int pcfrtc_gettime(struct todr_chip_handle *, struct timeval *);
int pcfrtc_settime(struct todr_chip_handle *, struct timeval *);
int pcfrtc_getcal(struct todr_chip_handle *, int *);
int pcfrtc_setcal(struct todr_chip_handle *, int);
int
pcfrtc_match(struct device *parent, void *v, void *arg)
{
struct i2c_attach_args *ia = arg;
if (strcmp(ia->ia_name, "nxp,pcf8523") == 0 &&
ia->ia_addr == PCF8523_ADDR)
return (1);
return (0);
}
void
pcfrtc_attach(struct device *parent, struct device *self, void *arg)
{
struct pcfrtc_softc *sc = (struct pcfrtc_softc *)self;
struct i2c_attach_args *ia = arg;
uint8_t reg;
sc->sc_tag = ia->ia_tag;
sc->sc_address = ia->ia_addr;
sc->sc_todr.cookie = sc;
sc->sc_todr.todr_gettime = pcfrtc_gettime;
sc->sc_todr.todr_settime = pcfrtc_settime;
sc->sc_todr.todr_getcal = pcfrtc_getcal;
sc->sc_todr.todr_setcal = pcfrtc_setcal;
sc->sc_todr.todr_setwen = NULL;
#if 0
todr_attach(&sc->sc_todr);
#else
/* XXX */
{
extern todr_chip_handle_t todr_handle;
todr_handle = &sc->sc_todr;
}
#endif
/*
* Enable battery switch-over and battery low detection in
* standard mode, and switch to 24 hour mode.
*/
reg = pcfrtc_reg_read(sc, PCF8523_CONTROL3);
reg &= ~PCF8523_CONTROL3_PM_MASK;
pcfrtc_reg_write(sc, PCF8523_CONTROL3, reg);
reg = pcfrtc_reg_read(sc, PCF8523_CONTROL1);
reg &= ~PCF8523_CONTROL1_12_24;
reg &= ~PCF8523_CONTROL1_STOP;
pcfrtc_reg_write(sc, PCF8523_CONTROL1, reg);
/* Report battery status. */
reg = pcfrtc_reg_read(sc, PCF8523_CONTROL3);
printf(": battery %s\n", (reg & PCF8523_CONTROL3_BLF) ? "low" : "ok");
/* Clear OS flag. */
reg = pcfrtc_reg_read(sc, PCF8523_SECONDS);
if (reg & PCF8523_SECONDS_OS) {
reg &= ~PCF8523_SECONDS_OS;
pcfrtc_reg_write(sc, PCF8523_SECONDS, reg);
}
}
int
pcfrtc_gettime(struct todr_chip_handle *ch, struct timeval *tv)
{
struct pcfrtc_softc *sc = ch->cookie;
struct clock_ymdhms dt;
memset(&dt, 0, sizeof(dt));
if (pcfrtc_clock_read(sc, &dt) == 0)
return (-1);
tv->tv_sec = clock_ymdhms_to_secs(&dt);
tv->tv_usec = 0;
return (0);
}
int
pcfrtc_settime(struct todr_chip_handle *ch, struct timeval *tv)
{
struct pcfrtc_softc *sc = ch->cookie;
struct clock_ymdhms dt;
clock_secs_to_ymdhms(tv->tv_sec, &dt);
if (pcfrtc_clock_write(sc, &dt) == 0)
return (-1);
return (0);
}
int
pcfrtc_setcal(struct todr_chip_handle *ch, int cal)
{
return (EOPNOTSUPP);
}
int
pcfrtc_getcal(struct todr_chip_handle *ch, int *cal)
{
return (EOPNOTSUPP);
}
uint8_t
pcfrtc_reg_read(struct pcfrtc_softc *sc, int reg)
{
uint8_t cmd = reg;
uint8_t val;
iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_address,
NULL, 0, &cmd, sizeof cmd, I2C_F_POLL) ||
iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_address,
NULL, 0, &val, sizeof val, I2C_F_POLL)) {
iic_release_bus(sc->sc_tag, I2C_F_POLL);
printf("%s: pcfrtc_reg_read: failed to read reg%d\n",
sc->sc_dev.dv_xname, reg);
return 0;
}
iic_release_bus(sc->sc_tag, I2C_F_POLL);
return val;
}
void
pcfrtc_reg_write(struct pcfrtc_softc *sc, int reg, uint8_t val)
{
uint8_t cmd = reg;
iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_address,
&cmd, sizeof cmd, &val, sizeof val, I2C_F_POLL)) {
iic_release_bus(sc->sc_tag, I2C_F_POLL);
printf("%s: pcfrtc_reg_write: failed to write reg%d\n",
sc->sc_dev.dv_xname, reg);
return;
}
iic_release_bus(sc->sc_tag, I2C_F_POLL);
}
int
pcfrtc_clock_read(struct pcfrtc_softc *sc, struct clock_ymdhms *dt)
{
uint8_t regs[PCF8523_NRTC_REGS];
uint8_t cmd = PCF8523_SECONDS;
iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_address,
NULL, 0, &cmd, sizeof cmd, I2C_F_POLL) ||
iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_address,
NULL, 0, regs, PCF8523_NRTC_REGS, I2C_F_POLL)) {
iic_release_bus(sc->sc_tag, I2C_F_POLL);
printf("%s: pcfrtc_clock_read: failed to read rtc\n",
sc->sc_dev.dv_xname);
return (0);
}
iic_release_bus(sc->sc_tag, I2C_F_POLL);
/*
* Convert the PCF8523's register values into something useable
*/
dt->dt_sec = FROMBCD(regs[0] & PCF8523_SECONDS_MASK);
dt->dt_min = FROMBCD(regs[1] & PCF8523_MINUTES_MASK);
dt->dt_hour = FROMBCD(regs[2] & PCF8523_HOURS_24MASK);
dt->dt_day = FROMBCD(regs[3] & PCF8523_DAY_MASK);
dt->dt_mon = FROMBCD(regs[5] & PCF8523_MONTH_MASK);
dt->dt_year = FROMBCD(regs[6]) + 2000;
if ((regs[0] & PCF8523_SECONDS_OS))
return (0);
return (1);
}
int
pcfrtc_clock_write(struct pcfrtc_softc *sc, struct clock_ymdhms *dt)
{
uint8_t regs[PCF8523_NRTC_REGS];
uint8_t cmd = PCF8523_SECONDS;
/*
* Convert our time representation into something the PCF8523
* can understand.
*/
regs[0] = TOBCD(dt->dt_sec);
regs[1] = TOBCD(dt->dt_min);
regs[2] = TOBCD(dt->dt_hour);
regs[3] = TOBCD(dt->dt_day);
regs[4] = TOBCD(dt->dt_wday);
regs[5] = TOBCD(dt->dt_mon);
regs[6] = TOBCD(dt->dt_year - 2000);
iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_address,
&cmd, sizeof cmd, regs, PCF8523_NRTC_REGS, I2C_F_POLL)) {
iic_release_bus(sc->sc_tag, I2C_F_POLL);
printf("%s: pcfrtc_clock_write: failed to write rtc\n",
sc->sc_dev.dv_xname);
return (0);
}
iic_release_bus(sc->sc_tag, I2C_F_POLL);
return (1);
}