0100-SerialBase-implement-sw-flow-control.patch

From d74af6c60c8098de8a7839a2af09f0159f673ca5 Mon Sep 17 00:00:00 2001
From: Martino Facchin <m.facchin@arduino.cc>
Date: Thu, 5 Aug 2021 15:13:58 +0200
Subject: [PATCH 100/204] SerialBase: implement sw flow control

---
 drivers/include/drivers/SerialBase.h |  9 ++++++++-
 drivers/source/SerialBase.cpp        | 14 ++++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/drivers/include/drivers/SerialBase.h b/drivers/include/drivers/SerialBase.h
index 9288c271e1..7d8734c7af 100644
--- a/drivers/include/drivers/SerialBase.h
+++ b/drivers/include/drivers/SerialBase.h
@@ -26,6 +26,9 @@
 #include "platform/mbed_toolchain.h"
 #include "platform/NonCopyable.h"
 
+#include "drivers/DigitalOut.h"
+#include "drivers/DigitalIn.h"
+
 #if DEVICE_SERIAL_ASYNCH
 #include "platform/CThunk.h"
 #include "hal/dma_api.h"
@@ -71,7 +74,8 @@ public:
         Disabled = 0,
         RTS,
         CTS,
-        RTSCTS
+        RTSCTS,
+        RTSCTS_SW
     };
 
     /** Set the transmission format used by the serial port
@@ -326,8 +330,11 @@ protected:
     Flow                           _flow_type = Disabled;
     PinName                        _flow1 = NC;
     PinName                        _flow2 = NC;
+    DigitalIn* _cts_pin;
+    DigitalOut* _rts_pin;
     const serial_fc_pinmap_t       *_static_pinmap_fc = NULL;
     void (SerialBase::*_set_flow_control_sp_func)(Flow, const serial_fc_pinmap_t &) = NULL;
+    bool sw_flow_control = false;
 #endif
 
 #endif
diff --git a/drivers/source/SerialBase.cpp b/drivers/source/SerialBase.cpp
index 40bf7d0b61..7c21d12e9c 100644
--- a/drivers/source/SerialBase.cpp
+++ b/drivers/source/SerialBase.cpp
@@ -71,6 +71,9 @@ int SerialBase::readable()
 {
     lock();
     int ret = serial_readable(&_serial);
+    if (sw_flow_control == true && _rts_pin != nullptr) {
+        *_rts_pin = !!!ret;
+    }
     unlock();
     return ret;
 }
@@ -80,6 +83,9 @@ int SerialBase::writeable()
 {
     lock();
     int ret = serial_writable(&_serial);
+    if (sw_flow_control) {
+        ret = ret & !(*_cts_pin);
+    }
     unlock();
     return ret;
 }
@@ -319,6 +325,14 @@ void SerialBase::set_flow_control(Flow type, PinName flow1, PinName flow2)
             serial_set_flow_control(&_serial, flow_type, flow1, flow2);
             break;
 
+        case RTSCTS_SW:
+            sw_flow_control = true;
+            if (_flow1 != NC)
+                _cts_pin = new DigitalIn(_flow1);
+            if (_flow2 != NC)
+                _rts_pin = new DigitalOut(_flow2, 0);
+            break;
+
         default:
             break;
     }
-- 
2.39.1