[src/trunk]: src/sys/dev/i2c Driver for EM Microelectronic EM3027 RTC and tem...

[uwe <uwe%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/9988ac9c575f
branches:  trunk
changeset: 358513:9988ac9c575f
user:      uwe <uwe%NetBSD.org@localhost>
date:      Fri Jan 05 03:07:15 2018 +0000

description:
Driver for EM Microelectronic EM3027 RTC and temperature sensor.

diffstat:

 sys/dev/i2c/em3027.c    |  480 ++++++++++++++++++++++++++++++++++++++++++++++++
 sys/dev/i2c/em3027reg.h |  138 +++++++++++++
 sys/dev/i2c/files.i2c   |    7 +-
 3 files changed, 624 insertions(+), 1 deletions(-)

diffs (truncated from 647 to 300 lines):

diff -r 5b4df326ed17 -r 9988ac9c575f sys/dev/i2c/em3027.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/dev/i2c/em3027.c      Fri Jan 05 03:07:15 2018 +0000
@@ -0,0 +1,480 @@
+/*     $NetBSD: em3027.c,v 1.1 2018/01/05 03:07:15 uwe Exp $ */
+/*
+ * Copyright (c) 2018 Valery Ushakov
+ * 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.
+ */
+
+/*
+ * EM Microelectronic EM3027 RTC
+ */
+#include <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: em3027.c,v 1.1 2018/01/05 03:07:15 uwe Exp $");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+#include <sys/kernel.h>
+
+#include <dev/clock_subr.h>
+
+#include <dev/i2c/i2cvar.h>
+#include <dev/i2c/em3027reg.h>
+#include <dev/sysmon/sysmonvar.h>
+
+#if 0
+#define aprint_verbose_dev     aprint_normal_dev
+#define aprint_debug_dev       aprint_normal_dev
+#endif
+
+
+struct em3027rtc_softc {
+       device_t sc_dev;
+
+       i2c_tag_t sc_tag;
+       i2c_addr_t sc_addr;
+
+       bool sc_vlow;
+
+       struct todr_chip_handle sc_todr;
+
+       struct sysmon_envsys *sc_sme;
+       envsys_data_t sc_sensor;
+};
+
+
+#define EM3027_CONTROL_BASE    EM3027_ONOFF
+#define EM3027_WATCH_BASE      EM3027_WATCH_SEC
+
+struct em3027rtc_watch {
+       uint8_t sec;
+       uint8_t min;
+       uint8_t hour;
+       uint8_t day;
+       uint8_t wday;
+       uint8_t mon;
+       uint8_t year;
+};
+
+#define EM3027_WATCH_SIZE      (EM3027_WATCH_YEAR - EM3027_WATCH_BASE + 1)
+__CTASSERT(sizeof(struct em3027rtc_watch) == EM3027_WATCH_SIZE);
+
+#define EM3027_BASE_YEAR       1980
+
+
+static int em3027rtc_match(device_t, cfdata_t, void *);
+static void em3027rtc_attach(device_t, device_t, void *);
+
+CFATTACH_DECL_NEW(em3027rtc, sizeof(struct em3027rtc_softc),
+    em3027rtc_match, em3027rtc_attach, NULL, NULL);
+
+
+static bool em3027rtc_enable_thermometer(struct em3027rtc_softc *);
+static void em3027rtc_envsys_attach(struct em3027rtc_softc *);
+
+static int em3027rtc_gettime(struct todr_chip_handle *, struct clock_ymdhms *);
+static int em3027rtc_settime(struct todr_chip_handle *, struct clock_ymdhms *);
+
+static void em3027rtc_sme_refresh(struct sysmon_envsys *, envsys_data_t *);
+
+static int em3027rtc_iic_exec(struct em3027rtc_softc *, i2c_op_t, uint8_t,
+                             void *, size_t);
+
+static int em3027rtc_read(struct em3027rtc_softc *, uint8_t, void *, size_t);
+static int em3027rtc_write(struct em3027rtc_softc *, uint8_t, void *, size_t);
+
+static int em3027rtc_read_byte(struct em3027rtc_softc *, uint8_t, uint8_t *);
+static int em3027rtc_write_byte(struct em3027rtc_softc *, uint8_t, uint8_t);
+
+
+
+static int
+em3027rtc_match(device_t parent, cfdata_t cf, void *aux)
+{
+       const struct i2c_attach_args *ia = aux;
+       uint8_t reg;
+       int error;
+
+       if (ia->ia_addr != EM3027_ADDR)
+               return 0;
+
+       /* check if the device is there */
+       error = iic_acquire_bus(ia->ia_tag, 0);
+       if (error)
+               return 0;
+
+       error = iic_smbus_read_byte(ia->ia_tag, ia->ia_addr,
+                                   EM3027_ONOFF, &reg, 0);
+       iic_release_bus(ia->ia_tag, 0);
+       if (error)
+               return 0;
+
+       return 1;
+}
+
+
+static void
+em3027rtc_attach(device_t parent, device_t self, void *aux)
+{
+       struct em3027rtc_softc *sc = device_private(self);
+       const struct i2c_attach_args *ia = aux;
+       struct ctl {
+               uint8_t onoff;
+               uint8_t irq_ctl;
+               uint8_t irq_flags;
+               uint8_t status;
+       } ctl;
+       int error;
+
+       aprint_naive(": Real-time Clock and Temperature Sensor\n");
+       aprint_normal(": Real-time Clock and Temperature Sensor\n");
+
+       sc->sc_dev = self;
+
+       sc->sc_tag = ia->ia_tag;
+       sc->sc_addr = ia->ia_addr;
+
+
+       /*
+        * Control Page registers
+        */
+       error = em3027rtc_read(sc, EM3027_CONTROL_BASE, &ctl, sizeof(ctl));
+       if (error) {
+               aprint_error_dev(sc->sc_dev,
+                   "failed to read control page (error %d)\n", error);
+               return;
+       }
+
+
+       /* Status */
+       aprint_debug_dev(sc->sc_dev, "status=0x%02x\n", ctl.status);
+
+       /* Complain about low voltage but continue anyway */
+       if (ctl.status & EM3027_STATUS_VLOW2) {
+               aprint_error_dev(sc->sc_dev, "voltage low (VLow2)\n");
+               sc->sc_vlow = true;
+       }
+       else if (ctl.status & EM3027_STATUS_VLOW1) {
+               aprint_error_dev(sc->sc_dev, "voltage low (VLow1)\n");
+               sc->sc_vlow = true;
+       }
+
+       ctl.status = EM3027_STATUS_POWER_ON;
+
+
+       /* On/Off */
+       aprint_debug_dev(sc->sc_dev, "on/off=0x%02x\n", ctl.onoff);
+
+       if ((ctl.onoff & EM3027_ONOFF_SR) == 0) {
+               aprint_verbose_dev(sc->sc_dev, "enabling self-recovery\n");
+               ctl.onoff |= EM3027_ONOFF_SR;
+       }
+
+       if ((ctl.onoff & EM3027_ONOFF_EEREF) == 0) {
+               aprint_verbose_dev(sc->sc_dev, "enabling EEPROM self-refresh\n");
+               ctl.onoff |= EM3027_ONOFF_EEREF;
+       }
+
+       ctl.onoff &= ~EM3027_ONOFF_TR;
+
+       if (ctl.onoff & EM3027_ONOFF_TI) {
+               aprint_verbose_dev(sc->sc_dev, "disabling timer\n");
+               ctl.onoff &= ~EM3027_ONOFF_TI;
+       }
+
+       if ((ctl.onoff & EM3027_ONOFF_WA) == 0) {
+               aprint_verbose_dev(sc->sc_dev, "enabling watch\n");
+               ctl.onoff |= EM3027_ONOFF_WA;
+       }
+
+
+       /* IRQ Control/Flags */
+       if (ctl.irq_ctl != 0)
+               aprint_debug_dev(sc->sc_dev,
+                   "irq=0x%02x - disabling all\n", ctl.irq_ctl);
+       ctl.irq_ctl = 0;
+       ctl.irq_flags = 0;
+
+
+       /* Write them back */
+       error = em3027rtc_write(sc, EM3027_CONTROL_BASE, &ctl, sizeof(ctl));
+       if (error) {
+               aprint_error_dev(sc->sc_dev,
+                   "failed to write control page (error %d)\n", error);
+               return;
+       }
+
+
+       /*
+        * Attach RTC
+        */
+       sc->sc_todr.cookie = sc;
+       sc->sc_todr.todr_gettime_ymdhms = em3027rtc_gettime;
+       sc->sc_todr.todr_settime_ymdhms = em3027rtc_settime;
+       sc->sc_todr.todr_setwen = NULL;
+
+       todr_attach(&sc->sc_todr);
+
+
+       /*
+        * Attach thermometer
+        */
+       em3027rtc_envsys_attach(sc);
+}
+
+
+static bool
+em3027rtc_enable_thermometer(struct em3027rtc_softc *sc)
+{
+       uint8_t eeprom_ctl;
+       int error;
+
+       error = em3027rtc_read_byte(sc, EM3027_EEPROM_CTL, &eeprom_ctl);
+       if (error) {
+               aprint_error_dev(sc->sc_dev,
+                   "failed to read eeprom control (error %d)\n", error);
+               return false;
+       }
+
+       aprint_debug_dev(sc->sc_dev, "eeprom ctl=0x%02x\n", eeprom_ctl);
+       if (eeprom_ctl & EM3027_EEPROM_THERM_ENABLE)
+               return true;
+
+       eeprom_ctl |= EM3027_EEPROM_THERM_ENABLE;
+       error = em3027rtc_write_byte(sc, EM3027_EEPROM_CTL, eeprom_ctl);
+       if (error) {
+               aprint_error_dev(sc->sc_dev,
+                   "failed to write eeprom control (error %d)\n", error);
+               return false;
+       }
+
+       return true;
+}
+
+
+static void
+em3027rtc_envsys_attach(struct em3027rtc_softc *sc)
+{
+       int error;
+
+       if (!em3027rtc_enable_thermometer(sc)) {
+               aprint_error_dev(sc->sc_dev, "thermometer not enabled\n");
+               return;
+       }
+
+       sc->sc_sme = sysmon_envsys_create();
+
+       sc->sc_sme->sme_name = device_xname(sc->sc_dev);
+       sc->sc_sme->sme_cookie = sc;
+       sc->sc_sme->sme_refresh = em3027rtc_sme_refresh;
+
+       sc->sc_sensor.units =  ENVSYS_STEMP;
+       sc->sc_sensor.state = ENVSYS_SINVALID;
+       sc->sc_sensor.flags = 0;
+       strlcpy(sc->sc_sensor.desc, "temperature", sizeof(sc->sc_sensor.desc));
+
+       error = sysmon_envsys_sensor_attach(sc->sc_sme, &sc->sc_sensor);
+       if (error) {