Implement MinimalSerial class

drivers/MinimalSerial.h

@@ -0,0 +1,99 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2019 ARM Limited
+ * 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.
+ */
+#ifndef MBED_MINIMAL_SERIAL_H
+#define MBED_MINIMAL_SERIAL_H
+
+#include "platform/platform.h"
+
+#if DEVICE_SERIAL || defined(DOXYGEN_ONLY)
+#include "hal/serial_api.h"
+#include "platform/NonCopyable.h"
+#include "PinNames.h"
+
+namespace mbed {
+
+/**
+ * \defgroup drivers_MinimalSerial MinimalSerial class
+ * \ingroup drivers-public-api-uart
+ * @{
+ */
+
+/** A abstract class for serial port implementations
+ */
+class MinimalSerial : private NonCopyable<MinimalSerial> {
+
+public:
+
+    enum Flow {
+        Disabled = 0,
+        RTS,
+        CTS,
+        RTSCTS
+    };
+
+#if DEVICE_SERIAL_FC
+    /** Set the flow control type on the serial port
+     *
+     *  @param type the flow control type (Disabled, RTS, CTS, RTSCTS)
+     *  @param flow1 the first flow control pin (RTS for RTS or RTSCTS, CTS for CTS)
+     *  @param flow2 the second flow control pin (CTS for RTSCTS)
+     */
+    void set_flow_control(Flow type, PinName flow1 = NC, PinName flow2 = NC);
+#endif // DEVICE_SERIAL_FC
+
+    /** Set the baud rate of the serial port
+     *
+     *  @param baudrate The baudrate of the serial port.
+     */
+    void baud(int baudrate);
+
+protected:
+    MinimalSerial(
+        PinName tx,
+        PinName rx,
+        int baud
+    );
+
+    MinimalSerial(
+        serial_t &serial_ref,
+        bool serial_inited,
+        PinName tx,
+        PinName rx,
+        int baud
+    );
+
+    virtual ~MinimalSerial();
+
+    int _base_getc();
+
+    int _base_putc(int c);    
+
+    int _baud;
+
+    serial_t _serial;
+
+private:
+    void init(PinName tx, PinName rx);
+};
+
+/** @}*/
+
+} // namespace mbed
+
+#endif // DEVICE_SERIAL || defined(DOXYGEN_ONLY)
+
+#endif // MBED_MINIMAL_SERIAL_H

drivers/SerialBase.h

@@ -1,5 +1,5 @@
 /* mbed Microcontroller Library
- * Copyright (c) 2006-2013 ARM Limited
+ * Copyright (c) 2006-2019 ARM Limited
  * SPDX-License-Identifier: Apache-2.0
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -25,6 +25,7 @@
 #include "hal/serial_api.h"
 #include "platform/mbed_toolchain.h"
 #include "platform/NonCopyable.h"
+#include "drivers/MinimalSerial.h"
 
 #if DEVICE_SERIAL_ASYNCH
 #include "platform/CThunk.h"
@@ -43,15 +44,9 @@ namespace mbed {
  *
  * @note Synchronization level: Set by subclass
  */
-class SerialBase : private NonCopyable<SerialBase> {
+class SerialBase : public MinimalSerial, private NonCopyable<SerialBase> {
 
 public:
-    /** Set the baud rate of the serial port
-     *
-     *  @param baudrate The baudrate of the serial port (default = 9600).
-     */
-    void baud(int baudrate);
-
     enum Parity {
         None = 0,
         Odd,
@@ -67,13 +62,6 @@ class SerialBase : private NonCopyable<SerialBase> {
         IrqCnt
     };
 
-    enum Flow {
-        Disabled = 0,
-        RTS,
-        CTS,
-        RTSCTS
-    };
-
     /** Set the transmission format used by the serial port
      *
      *  @param bits The number of bits in a word (5-8; default = 8)
@@ -168,16 +156,6 @@ class SerialBase : private NonCopyable<SerialBase> {
 #endif
 public:
 
-#if DEVICE_SERIAL_FC
-    /** Set the flow control type on the serial port
-     *
-     *  @param type the flow control type (Disabled, RTS, CTS, RTSCTS)
-     *  @param flow1 the first flow control pin (RTS for RTS or RTSCTS, CTS for CTS)
-     *  @param flow2 the second flow control pin (CTS for RTSCTS)
-     */
-    void set_flow_control(Flow type, PinName flow1 = NC, PinName flow2 = NC);
-#endif
-
     static void _irq_handler(uint32_t id, SerialIrq irq_type);
 
 #if DEVICE_SERIAL_ASYNCH
@@ -291,10 +269,6 @@ class SerialBase : private NonCopyable<SerialBase> {
     SerialBase(PinName tx, PinName rx, int baud);
     virtual ~SerialBase();
 
-    int _base_getc();
-
-    int _base_putc(int c);
-
 #if DEVICE_SERIAL_ASYNCH
     CThunk<SerialBase> _thunk_irq;
     DMAUsage _tx_usage;
@@ -304,10 +278,7 @@ class SerialBase : private NonCopyable<SerialBase> {
     bool _tx_asynch_set;
     bool _rx_asynch_set;
 #endif
-
-    serial_t         _serial;
     Callback<void()> _irq[IrqCnt];
-    int              _baud;
 #endif
 };
 

drivers/UnbufferedSerial.h

@@ -0,0 +1,182 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2019 ARM Limited
+ * 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.
+ */
+#ifndef MBED_UNBUFFERED_SERIAL_H
+#define MBED_UNBUFFERED_SERIAL_H
+
+#include "platform/platform.h"
+
+#if DEVICE_SERIAL || defined(DOXYGEN_ONLY)
+
+#include "drivers/SerialBase.h"
+#include "platform/FileHandle.h"
+#include "platform/NonCopyable.h"
+
+namespace mbed {
+
+/**
+ * \defgroup drivers_UnbufferedSerial UnbufferedSerial class
+ * \ingroup drivers-public-api-uart
+ * @{
+ */
+
+/**
+ * Class implementation for unbuffered I/O for an interrupt driven application
+ * or one that needs to have more control.
+ */
+class UnbufferedSerial:
+    public SerialBase,
+    public FileHandle,
+    private NonCopyable<UnbufferedSerial>
+{
+public:
+    /**
+     * Create a serial port instance connected to the specified transmit and
+     * receive pins, with the specified baud rate.
+     *
+     *  @param tx Transmit pin
+     *  @param rx Receive pin
+     *  @param baud The baud rate of the serial port (optional, defaults to MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE)
+     *
+     *  @note
+     *    Either tx or rx may be specified as NC if unused
+     */
+    UnbufferedSerial(
+        PinName tx,
+        PinName rx,
+        int baud = MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE
+    );
+
+        /** Write a char to the serial port
+     *
+     * @param c The char to write
+     *
+     * @returns The written char or -1 if an error occurred
+     */
+    int putc(int c);
+
+    /** Read a char from the serial port
+     *
+     * @returns The char read from the serial port
+     */
+    int getc();
+
+    /** Write a string to the serial port
+     *
+     * @param str The string to write
+     *
+     * @returns 0 if the write succeeds, EOF for error
+     */
+    int puts(const char *str);
+
+    /** Write the contents of a buffer to a file
+     *
+     *  Follows POSIX semantics:
+     *
+     * * if blocking, block until all data is written
+     * * if no data can be written, and non-blocking set, return -EAGAIN
+     * * if some data can be written, and non-blocking set, write partial
+     *
+     *  @param buffer   The buffer to write from
+     *  @param length   The number of bytes to write
+     *  @return         The number of bytes written, negative error on failure
+     */
+    virtual ssize_t write(const void *buffer, size_t size);
+
+    /** Read the contents of a file into a buffer
+     *
+     *  Follows POSIX semantics:
+     *
+     *  * if no data is available, and non-blocking set return -EAGAIN
+     *  * if no data is available, and blocking set, wait until data is available
+     *  * If any data is available, call returns immediately
+     *
+     *  @param buffer   The buffer to read in to
+     *  @param length   The number of bytes to read
+     *  @return         The number of bytes read, 0 at end of file, negative error on failure
+     */
+    virtual ssize_t read(void *buffer, size_t size);
+
+    /** Move the file position to a given offset from from a given location
+     *
+     * Not valid for a device type FileHandle like UARTSerial.
+     * In case of UARTSerial, returns ESPIPE
+     *
+     *  @param offset   The offset from whence to move to
+     *  @param whence   The start of where to seek
+     *      SEEK_SET to start from beginning of file,
+     *      SEEK_CUR to start from current position in file,
+     *      SEEK_END to start from end of file
+     *  @return         The new offset of the file, negative error code on failure
+     */
+    virtual off_t seek(off_t offset, int whence = SEEK_SET)
+    {
+        return -ESPIPE;
+    }
+
+    /** Get the size of the file
+     *
+     *  @return         Size of the file in bytes
+     */
+    virtual off_t size()
+    {
+        return -EINVAL;
+    }
+
+    /** Check if the file in an interactive terminal device
+     *
+     *  @return         True if the file is a terminal
+     *  @return         False if the file is not a terminal
+     *  @return         Negative error code on failure
+     */
+    virtual int isatty()
+    {
+        return true;
+    }
+
+    /** Close a file
+     *
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int close()
+    {
+        return 0;
+    }
+
+    /** 
+     * Equivalent to POSIX poll(). Derived from FileHandle.
+     * Provides a mechanism to multiplex input/output over a set of file
+     * handles.
+     */
+    virtual short poll(short events) const;
+
+#if !(DOXYGEN_ONLY)
+protected:
+    /* Acquire exclusive access to this serial port
+     */
+    virtual void lock(void);
+
+    /* Release exclusive access to this serial port
+     */
+    virtual void unlock(void);
+#endif // !(DOXYGEN_ONLY)
+};
+
+} // namespace mbed
+
+#endif // DEVICE_SERIAL || defined(DOXYGEN_ONLY)
+
+#endif // MBED_UNBUFFERED_SERIAL_H