stm32wb: rtc: initial registers

Backup registers are just hardcoded to 32, which is the max seen.
Note that the STM32WB only has 20!  I've captured that in the platform
yaml, even though it's not used anywhere (yet?)

Signed-off-by: Karl Palsson <karlp@tweak.net.au>

1 files changed, 24 insertions, 0 deletions

diff --git a/rtc/SConscript b/rtc/SConscript
new file mode 100644
index 0000000..f7956c0
--- /dev/null
+++ b/rtc/SConscript
@@ -0,0 +1,24 @@
+Import('env')
+
+headers = []
+instances = []
+sources = []
+aliases = {}
+
+periph = env['PLATFORM_SPEC'].get('periph', {})
+
+if 'stm32_rtc' in periph:
+    headers.append('stm32_rtc.h')
+    for name, data in periph['stm32_rtc'].items():
+        # Default to version 2, with subseconds, the most common form.
+        real_type = data.get('type', 'v2ss')
+        instances.append({
+            'type': 'STM32_RTC_t<STM32_RTC_reg_%s_t>' % real_type,
+            'name': name,
+            'args': [data['offset']],
+        })
+
+env.Jinja2('rtc.h', '../templates/periph_instances.h.j2', headers = headers, instances = instances, aliases = aliases)
+
+Return('sources')
+