From ab50a402d8879daee4fda5b91bb87c4a03339cc2 Mon Sep 17 00:00:00 2001
From: Andrzej Kaczmarek <andrzej.kaczmarek@codecoup.pl>
Date: Thu, 28 May 2020 17:05:54 +0200
Subject: [PATCH] hw/mcu/dialog: Add callbacks on enter/exit sleep

This patch adds callbacks to be called before and after deep sleep.
Those are intended to be registered by BSP which can then decide to
save/restore state of certain peripherals and release/acquire power
domains in order to save some power while M33 goes into deep sleep.

Note that similar power saving can usually be achieved if application
uses os_dev_open/close consistently, i.e. opens device only when
needed, which should properly acquire and release power domains
(although the actual behavior depends on a driver implementation).
However, there may still be some cases where quick save/restore is
possible and this can be handled in new callbacks.
---
 .../da1469x/include/mcu/da1469x_sleep.h       | 41 +++++++++++++++++++
 hw/mcu/dialog/da1469x/src/da1469x_sleep.c     | 29 +++++++++++--
 2 files changed, 67 insertions(+), 3 deletions(-)
 create mode 100755 hw/mcu/dialog/da1469x/include/mcu/da1469x_sleep.h

diff --git a/hw/mcu/dialog/da1469x/include/mcu/da1469x_sleep.h b/hw/mcu/dialog/da1469x/include/mcu/da1469x_sleep.h
new file mode 100755
index 0000000000..75e72a4d36
--- /dev/null
+++ b/hw/mcu/dialog/da1469x/include/mcu/da1469x_sleep.h
@@ -0,0 +1,41 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+#ifndef __MCU_DA1469X_SLEEP_H_
+#define __MCU_DA1469X_SLEEP_H_
+
+#include <stdbool.h>
+#include "os/os_time.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct da1469x_sleep_cb {
+    void (* enter_sleep)(os_time_t ticks);
+    void (* exit_sleep)(bool slept);
+};
+
+void da1469x_sleep_cb_register(struct da1469x_sleep_cb *cb);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  /* __MCU_DA1469X_SLEEP_H_ */
diff --git a/hw/mcu/dialog/da1469x/src/da1469x_sleep.c b/hw/mcu/dialog/da1469x/src/da1469x_sleep.c
index a476e83139..691097b0f1 100644
--- a/hw/mcu/dialog/da1469x/src/da1469x_sleep.c
+++ b/hw/mcu/dialog/da1469x/src/da1469x_sleep.c
@@ -22,6 +22,7 @@
 #include "mcu/da1469x_pd.h"
 #include "mcu/da1469x_pdc.h"
 #include "mcu/da1469x_prail.h"
+#include "mcu/da1469x_sleep.h"
 #include "mcu/mcu.h"
 #include "hal/hal_system.h"
 #include "da1469x_priv.h"
@@ -35,6 +36,8 @@ uint8_t g_mcu_pdc_combo_idx;
 static bool g_mcu_wait_for_jtag;
 static os_time_t g_mcu_wait_for_jtag_until;
 
+static struct da1469x_sleep_cb g_da1469x_sleep_cb;
+
 static inline bool
 da1469x_sleep_any_irq_pending(void)
 {
@@ -56,7 +59,7 @@ da1469x_sleep_is_blocked(void)
 void
 da1469x_sleep(os_time_t ticks)
 {
-    int ret;
+    int slept;
 
     da1469x_pdc_ack_all_m33();
 
@@ -69,10 +72,19 @@ da1469x_sleep(os_time_t ticks)
     /* PD_SYS will not be disabled here until we enter deep sleep, so don't wait */
     da1469x_pd_release_nowait(MCU_PD_DOMAIN_SYS);
 
+    if (g_da1469x_sleep_cb.enter_sleep) {
+        g_da1469x_sleep_cb.enter_sleep(ticks);
+    }
+
     mcu_gpio_enter_sleep();
-    ret = da1469x_m33_sleep();
+    slept = da1469x_m33_sleep();
     mcu_gpio_exit_sleep();
-    if (!ret) {
+
+    if (g_da1469x_sleep_cb.exit_sleep) {
+        g_da1469x_sleep_cb.exit_sleep(slept);
+    }
+
+    if (!slept) {
         /* We were not sleeping, no need to apply PD_SYS settings again */
         da1469x_pd_acquire_noconf(MCU_PD_DOMAIN_SYS);
         return;
@@ -101,6 +113,12 @@ da1469x_sleep(os_time_t ticks)
     da1469x_clock_sys_xtal32m_switch_safe();
 }
 
+void
+da1469x_sleep_cb_register(struct da1469x_sleep_cb *cb)
+{
+    g_da1469x_sleep_cb = *cb;
+}
+
 #else
 
 void
@@ -110,4 +128,9 @@ da1469x_sleep(os_time_t ticks)
     __WFI();
 }
 
+void
+da1469x_sleep_cb_register(struct da1469x_sleep_cb *cb)
+{
+}
+
 #endif