Diff: targets/TARGET_Silicon_Labs/TARGET_EFM32/sleep.c

Revision:

149:156823d33999

Parent:

144:ef7eb2e8f9f7

Child:

150:02e0a0aed4ec

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_Silicon_Labs/TARGET_EFM32/sleep.c	Fri Oct 28 11:17:30 2016 +0100
@@ -0,0 +1,104 @@
+/***************************************************************************//**
+ * @file sleep.c
+ *******************************************************************************
+ * @section License
+ * <b>(C) Copyright 2015 Silicon Labs, http://www.silabs.com</b>
+ *******************************************************************************
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ ******************************************************************************/
+
+#include "device.h"
+#if DEVICE_SLEEP
+
+#include "sleep_api.h"
+#include "sleepmodes.h"
+#include "cmsis.h"
+#include "em_emu.h"
+#include "critical.h"
+
+uint32_t sleep_block_counter[NUM_SLEEP_MODES] = {0};
+
+/**
+ * Sleep mode.
+ * Enter the lowest possible sleep mode that is not blocked by ongoing activity.
+ */
+void sleep(void)
+{
+    if (sleep_block_counter[0] > 0) {
+        /* Blocked everything below EM0, so just return */
+        return;
+    } else if (sleep_block_counter[1] > 0) {
+        /* Blocked everything below EM1, enter EM1 */
+        EMU_EnterEM1();
+    } else if (sleep_block_counter[2] > 0) {
+        /* Blocked everything below EM2, enter EM2 */
+        EMU_EnterEM2(true);
+    } else {
+        /* Blocked everything below EM3, enter EM3 */
+        EMU_EnterEM3(true);
+    } /* Never enter EM4, as mbed has no way of configuring EM4 wakeup */
+    return;
+}
+
+/**
+ * Deep Sleep mode.
+ * Enter Energy Mode 2, turning off all high-frequency clocks.
+ *
+ * In EM2 the high frequency oscillator is turned off, but with the 32.768 kHz
+ * oscillator running, selected low energy peripherals (LCD, RTC, LETIMER,
+ * PCNT, LEUART, I2C, LESENSE, OPAMP, USB, WDOG and ACMP) are still
+ * available. This gives a high degree of autonomous operation with a current
+ * consumption as low as 1.1 μA with RTC enabled. Power-on Reset, Brown-out
+ * Detection and full RAM and CPU retention is also included.
+ */
+void deepsleep(void)
+{
+    EMU_EnterEM2(true);
+}
+
+/** Block the microcontroller from sleeping below a certain mode
+ *
+ * This will block sleep() from entering an energy mode below the one given.
+ * -- To be called by peripheral HAL's --
+ *
+ * After the peripheral is finished with the operation, it should call unblock with the same state
+ *
+ */
+void blockSleepMode(sleepstate_enum minimumMode)
+{
+    core_util_critical_section_enter();
+    sleep_block_counter[minimumMode]++;
+    core_util_critical_section_exit();
+}
+
+/** Unblock the microcontroller from sleeping below a certain mode
+ *
+ * This will unblock sleep() from entering an energy mode below the one given.
+ * -- To be called by peripheral HAL's --
+ *
+ * This should be called after all transactions on a peripheral are done.
+ */
+void unblockSleepMode(sleepstate_enum minimumMode)
+{
+    core_util_critical_section_enter();
+    if(sleep_block_counter[minimumMode] > 0) {
+        sleep_block_counter[minimumMode]--;
+    }
+    core_util_critical_section_exit();
+}
+
+#endif