Differential D12833 Diff 34449 sys/dev/iicbus/rtc8583.c

Changeset View

Standalone View

sys/dev/iicbus/rtc8583.c

This file was added.

				/*-
				* Copyright (c) 2017 Hiroki Mori. All rights reserved.
				* Copyright (c) 2017 Ian Lepore. 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 THE AUTHOR ``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 THE AUTHOR 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.
				*
				* This code base on isl12xx.c
				*/

				#include <sys/cdefs.h>
				__FBSDID("$FreeBSD$");

				/*
				* Driver for EPSON RTC-8583
				*/

				#include "opt_platform.h"

				#include <sys/param.h>
				#include <sys/systm.h>
				#include <sys/bus.h>
				#include <sys/clock.h>
				#include <sys/kernel.h>
				#include <sys/lock.h>
				#include <sys/module.h>

				#ifdef FDT
				#include <dev/ofw/ofw_bus.h>
				#include <dev/ofw/ofw_bus_subr.h>
				#endif

				#include <dev/iicbus/iiconf.h>
				#include <dev/iicbus/iicbus.h>

				#include "clock_if.h"
				#include "iicbus_if.h"

				#define RTC8583_SC_REG 0x01 /* RTC Seconds */

				#define MAX_TRANSFER 16

				/*
				* A struct laid out in the same order as the time registers in the chip.
				*/
				struct time_regs {
				uint8_t msec, sec, min, hour, day, month;
				};

				struct rtc8583_softc {
				device_t dev;
				device_t busdev;
				struct intr_config_hook
				init_hook;
				};

				#ifdef FDT
				static struct ofw_compat_data compat_data[] = {
				{"epson,rtc8583", 1},
				{NULL, 0},
				};
				#endif

				static int
				rtc8583_writeto(device_t slavedev, uint8_t regaddr, void *buffer,
				uint16_t buflen, int waithow)
				{
				struct iic_msg msgs;
				uint8_t slaveaddr;
				uint8_t newbuf[MAX_TRANSFER];

				slaveaddr = iicbus_get_addr(slavedev);

				newbuf[0] = regaddr;
				memcpy(newbuf + 1, buffer, buflen);
				msgs.slave = slaveaddr;
				msgs.flags = IIC_M_WR;
				msgs.len = 1 + buflen;
				msgs.buf = newbuf;

				return (iicbus_transfer_excl(slavedev, &msgs, 1, waithow));
				}

				static inline int
				rtc8583_read1(struct rtc8583_softc sc, uint8_t reg, uint8_t data)
				{

				return (iicdev_readfrom(sc->dev, reg, data, 1, IIC_WAIT));
				}

				static inline int
				rtc8583_write1(struct rtc8583_softc *sc, uint8_t reg, uint8_t val)
				{

				return (rtc8583_writeto(sc->dev, reg, &val, 1, IIC_WAIT));
				}

				static void
				rtc8583_init(void *arg)
				{
				struct rtc8583_softc *sc = arg;

				config_intrhook_disestablish(&sc->init_hook);

				/*
				* Register as a system realtime clock.
				*/
				clock_register_flags(sc->dev, 1000000, CLOCKF_SETTIME_NO_ADJ);
				clock_schedule(sc->dev, 1);
				}

				static int
				rtc8583_probe(device_t dev)
				{

				#ifdef FDT
				if (!ofw_bus_status_okay(dev))
				return (ENXIO);

				if (ofw_bus_search_compatible(dev, compat_data)->ocd_data != 0) {
				device_set_desc(dev, "EPSON RTC-8583");
				return (BUS_PROBE_DEFAULT);
				}
				#endif
				return (ENXIO);
				}

				static int
				rtc8583_attach(device_t dev)
				{
				struct rtc8583_softc *sc = device_get_softc(dev);

				sc->dev = dev;
				sc->busdev = device_get_parent(sc->dev);

				/*
				* Chip init must wait until interrupts are enabled. Often i2c access
				* works only when the interrupts are available.
				*/
				sc->init_hook.ich_func = rtc8583_init;
				sc->init_hook.ich_arg = sc;
				if (config_intrhook_establish(&sc->init_hook) != 0)
				return (ENOMEM);

				return (0);
				}

				static int
				rtc8583_detach(device_t dev)
				{

				clock_unregister(dev);
				return (0);
				}

				static int
				rtc8583_gettime(device_t dev, struct timespec *ts)
				{
				struct rtc8583_softc *sc = device_get_softc(dev);
				struct clocktime ct;
				struct time_regs tregs;
				int err;
				uint8_t y, sreg;

				/* Read the bcd time registers. */
				if ((err = iicdev_readfrom(sc->dev, RTC8583_SC_REG, &tregs, sizeof(tregs),
				IIC_WAIT)) != 0)
				return (EINVAL);

				y = tregs.day >> 6;
				/* get year from sram */
				rtc8583_read1(sc, 0x10, &sreg);
				if (sreg % 4 != y) {
				/* 3 year is valid because of only 2 bit rtc value */
				if (sreg % 4 > y)
				sreg += (y + 4) - (sreg % 4);
				else
				sreg += y - (sreg % 4);
				if ((err = iicbus_request_bus(sc->busdev, sc->dev, IIC_WAIT)) != 0)
				return (err);
				rtc8583_write1(sc, 0x10, sreg);
				iicbus_release_bus(sc->busdev, sc->dev);
				}
				mizhkaUnsubmitted Not Done Inline Actions I see datasheet for this clock, but can't understand this algo :) ftp://download.epson-europe.com/pub/electronics-de/quartz/rtc8583.pdf is 0x10 register number mentioned in datasheet? Does it mean that year is stored in user S-RAM and don't describe in datasheet? mizhka: I see datasheet for this clock, but can't understand this algo :) ftp://download.epson-europe.

				ct.nsec = FROMBCD(tregs.msec) * 10 * 1000 * 1000;
				ct.sec = FROMBCD(tregs.sec);
				ct.min = FROMBCD(tregs.min);
				ct.hour = FROMBCD(tregs.hour & 0x3f);
				ct.day = FROMBCD(tregs.day & 0x3f);
				ct.mon = FROMBCD(tregs.month & 0x1f);
				ct.year = 2000 + sreg;

				return (clock_ct_to_ts(&ct, ts));
				}

				static int
				rtc8583_settime(device_t dev, struct timespec *ts)
				{
				struct rtc8583_softc *sc = device_get_softc(dev);
				struct clocktime ct;
				struct time_regs tregs;
				int err;
				uint8_t sreg;

				ts->tv_sec -= utc_offset();
				ts->tv_nsec = 0;
				clock_ts_to_ct(ts, &ct);

				tregs.sec = TOBCD(ct.sec);
				tregs.min = TOBCD(ct.min);
				tregs.hour = TOBCD(ct.hour);
				tregs.day = TOBCD(ct.day) \| ((ct.year % 4) << 6);
				tregs.month = TOBCD(ct.mon);

				if ((err = iicbus_request_bus(sc->busdev, sc->dev, IIC_WAIT)) != 0)
				return (err);
				err = rtc8583_writeto(sc->dev, RTC8583_SC_REG, &tregs,
				sizeof(tregs), IIC_WAIT);
				sreg = ct.year - 2000;
				/* save to year to sram */
				rtc8583_write1(sc, 0x10, sreg);
				iicbus_release_bus(sc->busdev, sc->dev);

				return (err);
				}

				static device_method_t rtc8583_methods[] = {
				/* device_if methods */
				DEVMETHOD(device_probe, rtc8583_probe),
				DEVMETHOD(device_attach, rtc8583_attach),
				DEVMETHOD(device_detach, rtc8583_detach),

				/* clock_if methods */
				DEVMETHOD(clock_gettime, rtc8583_gettime),
				DEVMETHOD(clock_settime, rtc8583_settime),

				DEVMETHOD_END,
				};

				static driver_t rtc8583_driver = {
				"rtc8583",
				rtc8583_methods,
				sizeof(struct rtc8583_softc),
				};
				static devclass_t rtc8583_devclass;

				DRIVER_MODULE(rtc8583, iicbus, rtc8583_driver, rtc8583_devclass, NULL, NULL);
				MODULE_VERSION(rtc8583, 1);
				MODULE_DEPEND(rtc8583, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);