- Add driver for Dallas Semiconductor DS1339 RTC sitting

  on I2C bus.

Reviewed by:	raj
Approved by:	imp
MFC after:	2 week

1 files changed, 232 insertions, 0 deletions

diff --git a/sys/dev/iicbus/ds1339.c b/sys/dev/iicbus/ds1339.c
new file mode 100644
index 0000000..bf7f420
--- /dev/null
+++ b/sys/dev/iicbus/ds1339.c
@@ -0,0 +1,232 @@
+/*-
+ * Copyright (c) 2008 Stanislav Sedov <stas@FreeBSD.org>,
+ *                    Rafal Jaworowski <raj@FreeBSD.org>.
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+/*
+ * Dallas Semiconductor DS1339 RTC sitting on the I2C bus.
+ */
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/module.h>
+#include <sys/clock.h>
+#include <sys/time.h>
+#include <sys/bus.h>
+#include <sys/resource.h>
+#include <sys/rman.h>
+
+#include <machine/bus.h>
+#include <machine/cpu.h>
+#include <machine/cpufunc.h>
+#include <machine/frame.h>
+#include <machine/resource.h>
+#include <machine/intr.h>
+
+#include <dev/iicbus/iicbus.h>
+#include <dev/iicbus/iiconf.h>
+
+#include "iicbus_if.h"
+#include "clock_if.h"
+
+#define	DS1339_ADDR		0xd0	/* slave address */
+#define	DS1339_DATE_REG		0x0
+#define	DS1339_CTRL_REG		0x0e
+#define	DS1339_OSCD_FLAG	0x80
+#define	DS1339_OSF_FLAG		0x80
+
+#define	DS1339_24H_FLAG		0x40	/* 24 hours mode. */
+#define	DS1339_PM_FLAG		0x20	/* AM/PM bit. */
+#define	DS1339_CENT_FLAG	0x80	/* Century selector. */
+#define	DS1339_CENT_SHIFT	7
+
+#define	HALFSEC	500000000	/* 1/2 of second. */
+
+struct ds1339_softc {
+	device_t		sc_dev;
+};
+
+static int
+ds1339_probe(device_t dev)
+{
+	struct ds1339_softc *sc;
+	int addr;
+
+	sc = device_get_softc(dev);
+	iicbus_get_addr(dev, &addr);
+	if (addr != DS1339_ADDR) {
+		if (bootverbose)
+			device_printf(dev, "fixed I2C slave address should "
+			    "be 0x%.2x instead of 0x%.2x.\n", DS1339_ADDR,
+			    addr);
+	}
+	device_set_desc(dev, "Dallas Semiconductor DS1339 RTC");
+	return (0);
+}
+
+static int
+ds1339_attach(device_t dev)
+{
+	struct ds1339_softc *sc = device_get_softc(dev);
+	int error;
+
+	sc->sc_dev = dev;
+
+	uint8_t addr[1] = { DS1339_CTRL_REG };
+	uint8_t rdata[2];
+	uint8_t wrdata[3];
+	struct iic_msg rmsgs[2] = {
+	     { DS1339_ADDR, IIC_M_WR, 1, addr },
+	     { DS1339_ADDR, IIC_M_RD, 2, rdata },
+	};
+	struct iic_msg wrmsgs[1] = {
+	     { DS1339_ADDR, IIC_M_WR, 3, wrdata },
+	};
+
+	/* Read control and status registers. */
+	error = iicbus_transfer(dev, rmsgs, 2);
+	if (error != 0) {
+		device_printf(dev, "could not read control registers.\n");
+		return (ENXIO);
+	}
+
+	if ((rdata[0] & DS1339_OSCD_FLAG) != 0)
+		rdata[0] &= ~DS1339_OSCD_FLAG;	/* Enable oscillator
+						 * if disabled.
+						 */
+	if ((rdata[1] & DS1339_OSF_FLAG) != 0)
+		rdata[1] &= ~DS1339_OSF_FLAG;	/* Clear oscillator stop flag */
+
+	/* Write modified registers back. */
+	wrdata[0] = DS1339_CTRL_REG;
+	wrdata[1] = rdata[0];
+	wrdata[2] = rdata[1];
+
+	goto out;
+
+	error = iicbus_transfer(dev, wrmsgs, 1);
+	if (error != 0) {
+		device_printf(dev, "could not write control registers.\n");
+		return (ENXIO);
+	}
+
+out:
+
+	clock_register(dev, 1000000);
+	return (0);
+}
+
+static uint8_t
+ds1339_get_hours(uint8_t val)
+{
+	uint8_t ret;
+
+	if (!(val & DS1339_24H_FLAG))
+		ret = FROMBCD(val & 0x3f);
+	else if (!(val & DS1339_PM_FLAG))
+		ret = FROMBCD(val & 0x1f);
+	else
+		ret = FROMBCD(val & 0x1f) + 12;
+
+	return (ret);
+}
+
+static int
+ds1339_gettime(device_t dev, struct timespec *ts)
+{
+	uint8_t addr[1] = { DS1339_DATE_REG };
+	uint8_t date[7];
+	struct iic_msg msgs[2] = {
+	     { DS1339_ADDR, IIC_M_WR, 1, addr },
+	     { DS1339_ADDR, IIC_M_RD, 7, date },
+	};
+	struct clocktime ct;
+	int error;
+
+	error = iicbus_transfer(dev, msgs, 2);
+	if (error == 0) {
+		ct.nsec = 0;
+		ct.sec = FROMBCD(date[0] & 0x7f);
+		ct.min = FROMBCD(date[1] & 0x7f);
+		ct.hour = ds1339_get_hours(date[2]);
+		ct.dow = FROMBCD(date[3] & 0x07) - 1;
+		ct.day = FROMBCD(date[4] & 0x3f);
+		ct.mon = FROMBCD(date[5] & 0x1f);
+		ct.year = 1900 + FROMBCD(date[6]) +
+		    ((date[5] & DS1339_CENT_FLAG) >> DS1339_CENT_SHIFT) * 100;
+
+		error = clock_ct_to_ts(&ct, ts);
+	}
+
+	return error;
+}
+
+static int
+ds1339_settime(device_t dev, struct timespec *ts)
+{
+	uint8_t data[8] = { DS1339_DATE_REG };	/* Register address. */
+	struct iic_msg msgs[1] = {
+	     { DS1339_ADDR, IIC_M_WR, 8, data },
+	};
+	struct clocktime ct;
+
+	clock_ts_to_ct(ts, &ct);
+
+	data[1] = TOBCD(ct.nsec >= HALFSEC ? ct.sec + 1 : ct.sec) & 0x7f;
+	data[2] = TOBCD(ct.min) & 0x7f;
+	data[3] = TOBCD(ct.hour) & 0x3f;	/* We use 24-hours mode. */
+	data[4] = TOBCD(ct.dow + 1) & 0x07;
+	data[5] = TOBCD(ct.day) & 0x3f;
+	data[6] = TOBCD(ct.mon) & 0x1f;
+	if (ct.year >= 2000) {
+		data[6] |= DS1339_CENT_FLAG;
+		data[7] = TOBCD(ct.year - 2000);
+	} else
+		data[7] = TOBCD(ct.year - 1900);
+
+	return iicbus_transfer(dev, msgs, 1);
+}
+
+static device_method_t ds1339_methods[] = {
+	DEVMETHOD(device_probe,		ds1339_probe),
+	DEVMETHOD(device_attach,	ds1339_attach),
+
+	DEVMETHOD(clock_gettime,	ds1339_gettime),
+	DEVMETHOD(clock_settime,	ds1339_settime),
+
+	{0, 0},
+};
+
+static driver_t ds1339_driver = {
+	"ds1339",
+	ds1339_methods,
+	sizeof(struct ds1339_softc),
+};
+static devclass_t ds1339_devclass;
+
+DRIVER_MODULE(ds1339, iicbus, ds1339_driver, ds1339_devclass, 0, 0);
+MODULE_VERSION(ds1339, 1);
+MODULE_DEPEND(ds1339, iicbus, 1, 1, 1);