git: 129028c79c6c - main - da9063_rtc: Add new driver for the Dialog Semiconductor DA9063 RTC

The branch main has been updated by jrtc27:

URL: https://cgit.FreeBSD.org/src/commit/?id=129028c79c6c287c3c028714e3e7993299357b6c

commit 129028c79c6c287c3c028714e3e7993299357b6c
Author:     Jessica Clarke <jrtc27@FreeBSD.org>
AuthorDate: 2022-09-13 16:46:21 +0000
Commit:     Jessica Clarke <jrtc27@FreeBSD.org>
CommitDate: 2022-09-13 16:46:21 +0000

    da9063_rtc: Add new driver for the Dialog Semiconductor DA9063 RTC
    
    This is a simple RTC present in the PMIC, supporting 1s precision.
    
    This is the PMIC on SiFive's HiFive Unmatched.
    
    Reviewed by:    mhorne, imp
    MFC after:      1 week
    Differential Revision:  https://reviews.freebsd.org/D36200
---
 sys/conf/files                     |   1 +
 sys/dev/dialog/da9063/da9063_rtc.c | 293 +++++++++++++++++++++++++++++++++++++
 2 files changed, 294 insertions(+)

diff --git a/sys/conf/files b/sys/conf/files
index c1cd7455a845..d7949dc5a069 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -1588,6 +1588,7 @@ dev/dcons/dcons_crom.c		optional dcons_crom
 dev/dcons/dcons_os.c		optional dcons
 dev/dialog/da9063/da9063_if.m	optional da9063_pmic
 dev/dialog/da9063/da9063_iic.c	optional da9063_pmic iicbus fdt
+dev/dialog/da9063/da9063_rtc.c	optional da9063_rtc fdt
 dev/dme/if_dme.c		optional dme
 dev/drm2/drm_agpsupport.c	optional drm2
 dev/drm2/drm_auth.c		optional drm2
diff --git a/sys/dev/dialog/da9063/da9063_rtc.c b/sys/dev/dialog/da9063/da9063_rtc.c
new file mode 100644
index 000000000000..1e6272b405db
--- /dev/null
+++ b/sys/dev/dialog/da9063/da9063_rtc.c
@@ -0,0 +1,293 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 2022 Jessica Clarke <jrtc27@FreeBSD.org>
+ *
+ * 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
+ */
+
+/* Dialog Semiconductor DA9063 RTC */
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/clock.h>
+#include <sys/lock.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+
+#include <dev/dialog/da9063/da9063reg.h>
+#include <dev/ofw/ofw_bus_subr.h>
+
+#include "clock_if.h"
+#include "da9063_if.h"
+
+#define	DA9063_RTC_BASE_YEAR	2000
+
+struct da9063_rtc_softc {
+	device_t	dev;
+	device_t	parent;
+	struct mtx	mtx;
+};
+
+#define	DA9063_RTC_LOCK(sc)		mtx_lock(&(sc)->mtx)
+#define	DA9063_RTC_UNLOCK(sc)		mtx_unlock(&(sc)->mtx)
+#define	DA9063_RTC_ASSERT_LOCKED(sc)	mtx_assert(&(sc)->mtx, MA_OWNED);
+#define	DA9063_RTC_ASSERT_UNLOCKED(sc)	mtx_assert(&(sc)->mtx, MA_NOTOWNED);
+
+static struct ofw_compat_data compat_data[] = {
+	{ "dlg,da9063-rtc",	1 },
+	{ NULL,			0 }
+};
+
+static int
+da9063_rtc_read_ct(struct da9063_rtc_softc *sc, struct clocktime *ct)
+{
+	uint8_t sec, min, hour, day, mon, year;
+	int error;
+
+	DA9063_RTC_ASSERT_LOCKED(sc)
+
+	error = DA9063_READ(sc->parent, DA9063_COUNT_S, &sec);
+	if (error != 0)
+		return (error);
+	if ((sec & DA9063_COUNT_S_RTC_READ) == 0)
+		return (EAGAIN);
+
+	error = DA9063_READ(sc->parent, DA9063_COUNT_MI, &min);
+	if (error != 0)
+		return (error);
+
+	error = DA9063_READ(sc->parent, DA9063_COUNT_H, &hour);
+	if (error != 0)
+		return (error);
+
+	error = DA9063_READ(sc->parent, DA9063_COUNT_D, &day);
+	if (error != 0)
+		return (error);
+
+	error = DA9063_READ(sc->parent, DA9063_COUNT_MO, &mon);
+	if (error != 0)
+		return (error);
+
+	error = DA9063_READ(sc->parent, DA9063_COUNT_Y, &year);
+	if (error != 0)
+		return (error);
+
+	ct->nsec = 0;
+	ct->dow = -1;
+	ct->sec = sec & DA9063_COUNT_S_COUNT_SEC_MASK;
+	ct->min = min & DA9063_COUNT_MI_COUNT_MIN_MASK;
+	ct->hour = hour & DA9063_COUNT_H_COUNT_HOUR_MASK;
+	ct->day = day & DA9063_COUNT_D_COUNT_DAY_MASK;
+	ct->mon = mon & DA9063_COUNT_MO_COUNT_MONTH_MASK;
+	ct->year = (year & DA9063_COUNT_Y_COUNT_YEAR_MASK) +
+	    DA9063_RTC_BASE_YEAR;
+
+	return (0);
+}
+
+static int
+da9063_rtc_write_ct(struct da9063_rtc_softc *sc, struct clocktime *ct)
+{
+	int error;
+
+	DA9063_RTC_ASSERT_LOCKED(sc)
+
+	error = DA9063_WRITE(sc->parent, DA9063_COUNT_S, ct->sec);
+	if (error != 0)
+		return (error);
+
+	error = DA9063_WRITE(sc->parent, DA9063_COUNT_MI, ct->min);
+	if (error != 0)
+		return (error);
+
+	error = DA9063_WRITE(sc->parent, DA9063_COUNT_H, ct->hour);
+	if (error != 0)
+		return (error);
+
+	error = DA9063_WRITE(sc->parent, DA9063_COUNT_D, ct->day);
+	if (error != 0)
+		return (error);
+
+	error = DA9063_WRITE(sc->parent, DA9063_COUNT_MO, ct->mon);
+	if (error != 0)
+		return (error);
+
+	error = DA9063_WRITE(sc->parent, DA9063_COUNT_Y,
+	    (ct->year - DA9063_RTC_BASE_YEAR) &
+	    DA9063_COUNT_Y_COUNT_YEAR_MASK);
+	if (error != 0)
+		return (error);
+
+	return (0);
+}
+
+static int
+da9063_rtc_gettime(device_t dev, struct timespec *ts)
+{
+	struct da9063_rtc_softc *sc;
+	struct clocktime ct, oldct;
+	int error;
+
+	sc = device_get_softc(dev);
+
+	DA9063_RTC_LOCK(sc);
+
+	error = da9063_rtc_read_ct(sc, &ct);
+	if (error != 0)
+		goto error;
+
+	/*
+	 * Reading seconds only latches the other registers for "approx 0.5s",
+	 * which should almost always be sufficient but is not guaranteed to
+	 * be, so re-read to get a consistent set of values.
+	 */
+	do {
+		oldct = ct;
+		error = da9063_rtc_read_ct(sc, &ct);
+		if (error != 0)
+			goto error;
+	} while (ct.min != oldct.min || ct.hour != oldct.hour ||
+	    ct.day != oldct.day || ct.mon != oldct.mon ||
+	    ct.year != oldct.year);
+
+	DA9063_RTC_UNLOCK(sc);
+
+	error = clock_ct_to_ts(&ct, ts);
+	if (error != 0)
+		return (error);
+
+	return (0);
+
+error:
+	DA9063_RTC_UNLOCK(sc);
+	return (error);
+}
+
+static int
+da9063_rtc_settime(device_t dev, struct timespec *ts)
+{
+	struct da9063_rtc_softc *sc;
+	struct clocktime ct;
+	int error;
+
+	sc = device_get_softc(dev);
+
+	/*
+	 * We request a timespec with no resolution-adjustment.  That also
+	 * disables utc adjustment, so apply that ourselves.
+	 */
+	ts->tv_sec -= utc_offset();
+	clock_ts_to_ct(ts, &ct);
+
+	DA9063_RTC_LOCK(sc);
+	error = da9063_rtc_write_ct(sc, &ct);
+	DA9063_RTC_UNLOCK(sc);
+
+	return (error);
+}
+
+static int
+da9063_rtc_probe(device_t dev)
+{
+	if (!ofw_bus_status_okay(dev))
+		return (ENXIO);
+
+	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
+		return (ENXIO);
+
+	device_set_desc(dev, "Dialog DA9063 RTC");
+
+	return (BUS_PROBE_DEFAULT);
+}
+
+static int
+da9063_rtc_attach(device_t dev)
+{
+	struct da9063_rtc_softc *sc;
+	int error;
+
+	sc = device_get_softc(dev);
+
+	sc->dev = dev;
+	sc->parent = device_get_parent(dev);
+
+	/* Power on RTC and 32 kHz oscillator */
+	error = DA9063_MODIFY(sc->parent, DA9063_CONTROL_E, 0,
+	    DA9063_CONTROL_E_RTC_EN);
+	if (error != 0)
+		return (error);
+
+	/* Connect 32 kHz oscillator */
+	error = DA9063_MODIFY(sc->parent, DA9063_EN_32K, 0,
+	    DA9063_EN_32K_CRYSTAL);
+	if (error != 0)
+		return (error);
+
+	/* Disable alarms */
+	error = DA9063_MODIFY(sc->parent, DA9063_ALARM_Y,
+	    DA9063_ALARM_Y_ALARM_ON | DA9063_ALARM_Y_TICK_ON, 0);
+	if (error != 0)
+		return (error);
+
+	mtx_init(&sc->mtx, device_get_nameunit(sc->dev), NULL, MTX_DEF);
+
+	/*
+	 * Register as a system realtime clock with 1 second resolution.
+	 */
+	clock_register_flags(dev, 1000000, CLOCKF_SETTIME_NO_ADJ);
+	clock_schedule(dev, 1);
+
+	return (0);
+}
+
+static int
+da9063_rtc_detach(device_t dev)
+{
+	struct da9063_rtc_softc *sc;
+
+	sc = device_get_softc(dev);
+
+	clock_unregister(dev);
+	mtx_destroy(&sc->mtx);
+
+	return (0);
+}
+
+static device_method_t da9063_rtc_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		da9063_rtc_probe),
+	DEVMETHOD(device_attach,	da9063_rtc_attach),
+	DEVMETHOD(device_detach,	da9063_rtc_detach),
+
+	/* Clock interface */
+	DEVMETHOD(clock_gettime,	da9063_rtc_gettime),
+	DEVMETHOD(clock_settime,	da9063_rtc_settime),
+
+	DEVMETHOD_END,
+};
+
+DEFINE_CLASS_0(da9063_rtc, da9063_rtc_driver, da9063_rtc_methods,
+    sizeof(struct da9063_rtc_softc));
+
+DRIVER_MODULE(da9063_rtc, da9063_pmic, da9063_rtc_driver, NULL, NULL);