feat(pmic): Add API-call to read battery voltage

Signed-off-by: Rahix <rahix@rahix.de>

epicardium/epicardium.h

@@ -32,6 +32,7 @@ typedef _Bool bool;
 #define API_SYSTEM_EXIT             0x1
 #define API_SYSTEM_EXEC             0x2
 #define API_SYSTEM_RESET            0x3
+#define API_BATTERY_VOLTAGE         0x4
 
 #define API_INTERRUPT_ENABLE        0xA
 #define API_INTERRUPT_DISABLE       0xB
@@ -210,6 +211,16 @@ API(API_SYSTEM_EXEC, int __epic_exec(char *name));
  */
 API(API_SYSTEM_RESET, void epic_system_reset(void));
 
+/**
+ * Battery Voltage
+ * ===============
+ */
+
+/**
+ * Read the current battery voltage.
+ */
+API(API_BATTERY_VOLTAGE, int epic_read_battery_voltage(float *result));
+
 /**
  * UART/Serial Interface
  * =====================

epicardium/modules/pmic.c

@@ -180,6 +180,14 @@ static void pmic_check_battery()
 	 */
 }
 
+/*
+ * API-call for battery voltage
+ */
+int epic_read_battery_voltage(float *result)
+{
+	return pmic_read_amux(PMIC_AMUX_BATT_U, result);
+}
+
 static StaticTimer_t pmic_timer_data;
 static void vPmicTimerCb(TimerHandle_t xTimer)
 {

pycardium/modules/os.c

@@ -123,6 +123,18 @@ static mp_obj_t mp_os_rename(mp_obj_t py_oldp, mp_obj_t py_newp)
 }
 static MP_DEFINE_CONST_FUN_OBJ_2(rename_obj, mp_os_rename);
 
+static mp_obj_t mp_os_read_battery()
+{
+	float result;
+	int res = epic_read_battery_voltage(&result);
+	if (res < 0) {
+		mp_raise_OSError(-res);
+	}
+
+	return mp_obj_new_float(result);
+}
+static MP_DEFINE_CONST_FUN_OBJ_0(read_battery_obj, mp_os_read_battery);
+
 static const mp_rom_map_elem_t os_module_globals_table[] = {
 	{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_os) },
 	{ MP_ROM_QSTR(MP_QSTR_exit), MP_ROM_PTR(&exit_obj) },
@@ -132,6 +144,7 @@ static const mp_rom_map_elem_t os_module_globals_table[] = {
 	{ MP_ROM_QSTR(MP_QSTR_unlink), MP_ROM_PTR(&unlink_obj) },
 	{ MP_ROM_QSTR(MP_QSTR_mkdir), MP_ROM_PTR(&mkdir_obj) },
 	{ MP_ROM_QSTR(MP_QSTR_rename), MP_ROM_PTR(&rename_obj) },
+	{ MP_ROM_QSTR(MP_QSTR_read_battery), MP_ROM_PTR(&read_battery_obj) },
 };
 
 static MP_DEFINE_CONST_DICT(os_module_globals, os_module_globals_table);

pycardium/modules/qstrdefs.h

@@ -105,6 +105,7 @@ Q(listdir)
 Q(unlink)
 Q(mkdir)
 Q(rename)
+Q(read_battery)
 
 /* gpio */
 Q(gpio)