Add rtc module

Add an rtc module that provides a singleton RTC class with
- a datetime property to set and get time if the board supports it.
- a calbration property to adjust the clock.

There's also an rtc.set_time_source() method to override this RTC object using pure python.

The time module gets 3 methods:
- time.time()
- time.localtime()
- time.mktime()

The rtc timesource is used to provide time to the time module.

lib/timeutils is used for time conversions and thus only supports dates after 2000.

6 files changed, 436 insertions, 0 deletions

diff --git a/shared-bindings/rtc/RTC.c b/shared-bindings/rtc/RTC.c
new file mode 100644
index 000000000..30df20145
--- /dev/null
+++ b/shared-bindings/rtc/RTC.c
@@ -0,0 +1,135 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Noralf Trønnes
+ * Copyright (c) 2013, 2014 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <string.h>
+
+#include "py/obj.h"
+#include "py/objproperty.h"
+#include "py/runtime.h"
+#include "lib/timeutils/timeutils.h"
+#include "shared-bindings/rtc/__init__.h"
+#include "shared-bindings/rtc/RTC.h"
+#include "shared-bindings/time/__init__.h"
+
+void MP_WEAK common_hal_rtc_get_time(timeutils_struct_time_t *tm) {
+    mp_raise_NotImplementedError("RTC is not supported on this board");
+}
+
+void MP_WEAK common_hal_rtc_set_time(timeutils_struct_time_t *tm) {
+    mp_raise_NotImplementedError("RTC is not supported on this board");
+}
+
+int MP_WEAK common_hal_rtc_get_calibration(void) {
+    return 0;
+}
+
+void MP_WEAK common_hal_rtc_set_calibration(int calibration) {
+    mp_raise_NotImplementedError("RTC calibration is not supported on this board");
+}
+
+const rtc_rtc_obj_t rtc_rtc_obj = {{&rtc_rtc_type}};
+
+//| .. currentmodule:: rtc
+//|
+//| :class:`RTC` --- Real Time Clock
+//| --------------------------------
+//|
+//| .. class:: RTC()
+//|
+//|   This class represents the onboard Real Time Clock. It is a singleton and will always return the same instance.
+//|
+STATIC mp_obj_t rtc_rtc_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
+    // No arguments
+    mp_arg_check_num(n_args, n_kw, 0, 0, false);
+
+    // return constant object
+    return (mp_obj_t)&rtc_rtc_obj;
+}
+
+//|   .. attribute:: datetime
+//|
+//|       Get or set the date and time of the RTC.
+//|
+STATIC mp_obj_t rtc_rtc_obj_get_datetime(mp_obj_t self_in) {
+    timeutils_struct_time_t tm;
+    common_hal_rtc_get_time(&tm);
+    return struct_time_from_tm(&tm);
+}
+MP_DEFINE_CONST_FUN_OBJ_1(rtc_rtc_get_datetime_obj, rtc_rtc_obj_get_datetime);
+
+STATIC mp_obj_t rtc_rtc_obj_set_datetime(mp_obj_t self_in, mp_obj_t datetime) {
+    timeutils_struct_time_t tm;
+    struct_time_to_tm(datetime, &tm);
+    common_hal_rtc_set_time(&tm);
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_2(rtc_rtc_set_datetime_obj, rtc_rtc_obj_set_datetime);
+
+const mp_obj_property_t rtc_rtc_datetime_obj = {
+    .base.type = &mp_type_property,
+    .proxy = {(mp_obj_t)&rtc_rtc_get_datetime_obj,
+              (mp_obj_t)&rtc_rtc_set_datetime_obj,
+              (mp_obj_t)&mp_const_none_obj},
+};
+
+//|   .. attribute:: calibration
+//|
+//|     The RTC calibration value.
+//|     A positive value speeds up the clock and a negative value slows it down.
+//|     Range and value is hardware specific, but one step is often approx. 1 ppm.
+//|
+STATIC mp_obj_t rtc_rtc_obj_get_calibration(mp_obj_t self_in) {
+    int calibration = common_hal_rtc_get_calibration();
+    return mp_obj_new_int(calibration);
+}
+MP_DEFINE_CONST_FUN_OBJ_1(rtc_rtc_get_calibration_obj, rtc_rtc_obj_get_calibration);
+
+STATIC mp_obj_t rtc_rtc_obj_set_calibration(mp_obj_t self_in, mp_obj_t calibration) {
+    common_hal_rtc_set_calibration(mp_obj_get_int(calibration));
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_2(rtc_rtc_set_calibration_obj, rtc_rtc_obj_set_calibration);
+
+const mp_obj_property_t rtc_rtc_calibration_obj = {
+    .base.type = &mp_type_property,
+    .proxy = {(mp_obj_t)&rtc_rtc_get_calibration_obj,
+              (mp_obj_t)&rtc_rtc_set_calibration_obj,
+              (mp_obj_t)&mp_const_none_obj},
+};
+
+STATIC const mp_rom_map_elem_t rtc_rtc_locals_dict_table[] = {
+    { MP_ROM_QSTR(MP_QSTR_datetime), MP_ROM_PTR(&rtc_rtc_datetime_obj) },
+    { MP_ROM_QSTR(MP_QSTR_calibration), MP_ROM_PTR(&rtc_rtc_calibration_obj) },
+};
+STATIC MP_DEFINE_CONST_DICT(rtc_rtc_locals_dict, rtc_rtc_locals_dict_table);
+
+const mp_obj_type_t rtc_rtc_type = {
+    { &mp_type_type },
+    .name = MP_QSTR_RTC,
+    .make_new = rtc_rtc_make_new,
+    .locals_dict = (mp_obj_dict_t*)&rtc_rtc_locals_dict,
+};
diff --git a/shared-bindings/rtc/RTC.h b/shared-bindings/rtc/RTC.h
new file mode 100644
index 000000000..76510bd72
--- /dev/null
+++ b/shared-bindings/rtc/RTC.h
@@ -0,0 +1,49 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Noralf Trønnes
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_SHARED_BINDINGS_RTC_RTC_H
+#define MICROPY_INCLUDED_SHARED_BINDINGS_RTC_RTC_H
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "lib/timeutils/timeutils.h"
+
+extern void common_hal_rtc_get_time(timeutils_struct_time_t *tm);
+extern void common_hal_rtc_set_time(timeutils_struct_time_t *tm);
+
+extern int common_hal_rtc_get_calibration(void);
+extern void common_hal_rtc_set_calibration(int calibration);
+
+extern const mp_obj_type_t rtc_rtc_type;
+
+typedef struct _rtc_rtc_obj_t {
+    mp_obj_base_t base;
+} rtc_rtc_obj_t;
+
+extern const rtc_rtc_obj_t rtc_rtc_obj;
+
+#endif  // MICROPY_INCLUDED_SHARED_BINDINGS_RTC_RTC_H
diff --git a/shared-bindings/rtc/__init__.c b/shared-bindings/rtc/__init__.c
new file mode 100644
index 000000000..89e3a24dd
--- /dev/null
+++ b/shared-bindings/rtc/__init__.c
@@ -0,0 +1,93 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Noralf Trønnes
+ * Copyright (c) 2013, 2014 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "py/obj.h"
+#include "py/runtime.h"
+#include "shared-bindings/rtc/__init__.h"
+#include "shared-bindings/rtc/RTC.h"
+#include "shared-bindings/time/__init__.h"
+
+//| :mod:`rtc` --- Real Time Clock
+//| ========================================================
+//|
+//| .. module:: rtc
+//|   :synopsis: Real Time Clock
+//|   :platform: SAMD21
+//|
+//| The `rtc` module provides support for a Real Time Clock.
+//| It also backs the `time.time()` and `time.localtime()` functions using the onboard RTC if present.
+//|
+
+void rtc_reset(void) {
+    MP_STATE_VM(rtc_time_source) = (mp_obj_t)&rtc_rtc_obj;
+}
+
+mp_obj_t rtc_get_time_source_time(void) {
+    mp_obj_t datetime = mp_load_attr(MP_STATE_VM(rtc_time_source), MP_QSTR_datetime);
+    timeutils_struct_time_t tm;
+    struct_time_to_tm(datetime, &tm);
+    // This sets tm_wday and tm_yday
+    return struct_time_from_tm(&tm);
+}
+
+//| .. function:: set_time_source(rtc)
+//|
+//|   Sets the rtc time source used by time.localtime().
+//|   The default is `rtc.RTC()`.
+//|
+//|   Example usage::
+//|
+//|     import rtc
+//|     import time
+//|
+//|     class RTC(object):
+//|         @property
+//|         def datetime(self):
+//|             return time.struct_time((2018, 3, 17, 21, 1, 47, 0, 0, 0))
+//|
+//|     r = RTC()
+//|     rtc.set_time_source(r)
+//|
+STATIC mp_obj_t rtc_set_time_source(mp_obj_t time_source) {
+    MP_STATE_VM(rtc_time_source) = time_source;
+
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_1(rtc_set_time_source_obj, rtc_set_time_source);
+
+STATIC const mp_rom_map_elem_t rtc_module_globals_table[] = {
+    { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_rtc) },
+    { MP_ROM_QSTR(MP_QSTR_set_time_source), MP_ROM_PTR(&rtc_set_time_source_obj) },
+    { MP_ROM_QSTR(MP_QSTR_RTC), MP_ROM_PTR(&rtc_rtc_type) },
+};
+
+STATIC MP_DEFINE_CONST_DICT(rtc_module_globals, rtc_module_globals_table);
+
+const mp_obj_module_t rtc_module = {
+    .base = { &mp_type_module },
+    .globals = (mp_obj_dict_t*)&rtc_module_globals,
+};
diff --git a/shared-bindings/rtc/__init__.h b/shared-bindings/rtc/__init__.h
new file mode 100644
index 000000000..0ee51fba5
--- /dev/null
+++ b/shared-bindings/rtc/__init__.h
@@ -0,0 +1,33 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Noralf Trønnes
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_SHARED_BINDINGS_RTC___INIT___H
+#define MICROPY_INCLUDED_SHARED_BINDINGS_RTC___INIT___H
+
+extern void rtc_reset(void);
+extern mp_obj_t rtc_get_time_source_time(void);
+
+#endif  // MICROPY_INCLUDED_SHARED_BINDINGS_RTC___INIT___H
diff --git a/shared-bindings/time/__init__.c b/shared-bindings/time/__init__.c
index 6956cc4e6..b4137706e 100644
--- a/shared-bindings/time/__init__.c
+++ b/shared-bindings/time/__init__.c
@@ -30,6 +30,8 @@
 
 #include "py/obj.h"
 #include "py/objnamedtuple.h"
+#include "lib/timeutils/timeutils.h"
+#include "shared-bindings/rtc/__init__.h"
 #include "shared-bindings/time/__init__.h"
 
 //| :mod:`time` --- time and timing related functions
@@ -133,6 +135,122 @@ const mp_obj_namedtuple_type_t struct_time_type_obj = {
         MP_QSTR_tm_isdst
     },
 };
+
+mp_obj_t struct_time_from_tm(timeutils_struct_time_t *tm) {
+    timeutils_struct_time_t tmp;
+    mp_uint_t secs = timeutils_seconds_since_2000(tm->tm_year, tm->tm_mon, tm->tm_mday,
+                                                  tm->tm_hour, tm->tm_min, tm->tm_sec);
+    timeutils_seconds_since_2000_to_struct_time(secs, &tmp);
+    tm->tm_wday = tmp.tm_wday;
+    tm->tm_yday = tmp.tm_yday;
+
+    mp_obj_t elems[9] = {
+        mp_obj_new_int(tm->tm_year),
+        mp_obj_new_int(tm->tm_mon),
+        mp_obj_new_int(tm->tm_mday),
+        mp_obj_new_int(tm->tm_hour),
+        mp_obj_new_int(tm->tm_min),
+        mp_obj_new_int(tm->tm_sec),
+        mp_obj_new_int(tm->tm_wday),
+        mp_obj_new_int(tm->tm_yday),
+        mp_obj_new_int(-1), // tm_isdst is not supported
+    };
+
+    return namedtuple_make_new((const mp_obj_type_t*)&struct_time_type_obj, 9, 0, elems);
+};
+
+void struct_time_to_tm(mp_obj_t t, timeutils_struct_time_t *tm) {
+    mp_obj_t *elems;
+    size_t len;
+
+    if (!MP_OBJ_IS_TYPE(t, &mp_type_tuple) && !MP_OBJ_IS_TYPE(t, MP_OBJ_FROM_PTR(&struct_time_type_obj))) {
+        mp_raise_TypeError("Tuple or struct_time argument required");
+    }
+
+    mp_obj_tuple_get(t, &len, &elems);
+    if (len != 9) {
+        mp_raise_TypeError("function takes exactly 9 arguments");
+    }
+
+    tm->tm_year = mp_obj_get_int(elems[0]);
+    tm->tm_mon = mp_obj_get_int(elems[1]);
+    tm->tm_mday = mp_obj_get_int(elems[2]);
+    tm->tm_hour = mp_obj_get_int(elems[3]);
+    tm->tm_min = mp_obj_get_int(elems[4]);
+    tm->tm_sec = mp_obj_get_int(elems[5]);
+    tm->tm_wday = mp_obj_get_int(elems[6]);
+    tm->tm_yday = mp_obj_get_int(elems[7]);
+    // elems[8] tm_isdst is not supported
+}
+
+mp_obj_t MP_WEAK rtc_get_time_source_time(void) {
+    mp_raise_RuntimeError("RTC is not supported on this board");
+}
+
+//| .. method:: time()
+//|
+//|   Return the current time in seconds since since Jan 1, 2000.
+//|
+//|   :return: the current time
+//|   :rtype: int
+//|
+STATIC mp_obj_t time_time(void) {
+    timeutils_struct_time_t tm;
+    struct_time_to_tm(rtc_get_time_source_time(), &tm);
+    mp_uint_t secs = timeutils_seconds_since_2000(tm.tm_year, tm.tm_mon, tm.tm_mday, // mp_uint_t date
+                                                  tm.tm_hour, tm.tm_min, tm.tm_sec);
+    return mp_obj_new_int_from_uint(secs);
+}
+MP_DEFINE_CONST_FUN_OBJ_0(time_time_obj, time_time);
+
+//| .. method:: localtime([secs])
+//|
+//|   Convert a time expressed in seconds since Jan 1, 2000 to a struct_time in
+//|   local time. If secs is not provided or None, the current time as returned
+//|   by time() is used.
+//|
+//|   :return: the current time
+//|   :rtype: time.struct_time
+//|
+STATIC mp_obj_t time_localtime(size_t n_args, const mp_obj_t *args) {
+    if (n_args == 0 || args[0] == mp_const_none) {
+        return rtc_get_time_source_time();
+    }
+
+    timeutils_struct_time_t tm;
+    timeutils_seconds_since_2000_to_struct_time(mp_obj_get_int(args[0]), &tm);
+
+    return struct_time_from_tm(&tm);
+}
+MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(time_localtime_obj, 0, 1, time_localtime);
+
+//| .. method:: mktime(t)
+//|
+//|   This is the inverse function of localtime(). Its argument is the
+//|   struct_time or full 9-tuple (since the dst flag is needed; use -1 as the
+//|   dst flag if it is unknown) which expresses the time in local time, not UTC.
+//|   The earliest date for which it can generate a time is Jan 1, 2000.
+//|
+//|   :return: seconds
+//|   :rtype: int
+//|
+STATIC mp_obj_t time_mktime(mp_obj_t t) {
+    mp_obj_t *elem;
+    size_t len;
+
+    if (!MP_OBJ_IS_TYPE(t, &mp_type_tuple) && !MP_OBJ_IS_TYPE(t, MP_OBJ_FROM_PTR(&struct_time_type_obj))) {
+        mp_raise_TypeError("Tuple or struct_time argument required");
+    }
+
+    mp_obj_tuple_get(t, &len, &elem);
+    if (len != 9) {
+        mp_raise_TypeError("function takes exactly 9 arguments");
+    }
+
+    return mp_obj_new_int_from_uint(timeutils_mktime(mp_obj_get_int(elem[0]), mp_obj_get_int(elem[1]), mp_obj_get_int(elem[2]),
+                                                     mp_obj_get_int(elem[3]), mp_obj_get_int(elem[4]), mp_obj_get_int(elem[5])));
+}
+MP_DEFINE_CONST_FUN_OBJ_1(time_mktime_obj, time_mktime);
 #endif
 
 STATIC const mp_rom_map_elem_t time_module_globals_table[] = {
@@ -142,7 +260,10 @@ STATIC const mp_rom_map_elem_t time_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR_sleep), MP_ROM_PTR(&time_sleep_obj) },
     #if MICROPY_PY_COLLECTIONS
     { MP_ROM_QSTR(MP_QSTR_struct_time), MP_ROM_PTR(&struct_time_type_obj) },
+    { MP_ROM_QSTR(MP_QSTR_localtime), MP_ROM_PTR(&time_localtime_obj) },
+    { MP_ROM_QSTR(MP_QSTR_mktime), MP_ROM_PTR(&time_mktime_obj) },
     #endif
+    { MP_ROM_QSTR(MP_QSTR_time), MP_ROM_PTR(&time_time_obj) },
 };
 
 STATIC MP_DEFINE_CONST_DICT(time_module_globals, time_module_globals_table);
diff --git a/shared-bindings/time/__init__.h b/shared-bindings/time/__init__.h
index f6ecb5989..c5a0b47fc 100644
--- a/shared-bindings/time/__init__.h
+++ b/shared-bindings/time/__init__.h
@@ -30,6 +30,11 @@
 #include <stdint.h>
 #include <stdbool.h>
 
+#include "lib/timeutils/timeutils.h"
+
+extern mp_obj_t struct_time_from_tm(timeutils_struct_time_t *tm);
+extern void struct_time_to_tm(mp_obj_t t, timeutils_struct_time_t *tm);
+
 extern uint64_t common_hal_time_monotonic(void);
 extern void common_hal_time_delay_ms(uint32_t);