Diff: src/mbed/adi_sense_spi.cpp

Revision:

0:76fed7dd9235

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/mbed/adi_sense_spi.cpp	Thu Jan 25 16:00:23 2018 +0000
@@ -0,0 +1,210 @@
+/*!
+ ******************************************************************************
+ * @file:   adi_sense_spi.cpp
+ * @brief:  ADI Sense OS-dependent wrapper layer for SPI interface
+ *-----------------------------------------------------------------------------
+ */
+
+/******************************************************************************
+Copyright 2017 (c) Analog Devices, Inc.
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+  - Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+  - Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+  - Neither the name of Analog Devices, Inc. nor the names of its
+    contributors may be used to endorse or promote products derived
+    from this software without specific prior written permission.
+  - The use of this software may or may not infringe the patent rights
+    of one or more patent holders. This license does not release you
+    from the requirement that you obtain separate licenses from these
+    patent holders to use this software.
+  - Use of the software either in source or binary form, must be run
+    on or directly connected to an Analog Devices Inc. component.
+
+THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT,
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, INTELLECTUAL PROPERTY RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *****************************************************************************/
+
+#include <mbed.h>
+
+#include "inc/adi_sense_spi.h"
+#include "inc/adi_sense_log.h"
+
+#define ADI_SENSE_SPI_MODE       0 /* CPOL=0, CPHA=0 */
+#define ADI_SENSE_SPI_FRAME_SIZE 8 /* 8-bit frame size */
+
+class SpiContext
+{
+public:
+    SpiContext(
+        PinName mosiPin,
+        PinName misoPin,
+        PinName sckPin,
+        PinName csPin,
+        unsigned maxSpeed);
+
+    int transfer(
+        void *pTxData,
+        void *pRxData,
+        unsigned nLength,
+        bool bCsHold);
+
+private:
+    SPI _spi;
+    DigitalOut _cs;
+
+    event_callback_t _callback;
+    volatile int     _cbEvent;
+    volatile bool    _cbFired;
+
+    void _cbHandler(
+        int event);
+
+    int _waitForCallback(
+        void);
+};
+
+SpiContext::SpiContext(PinName mosiPin,
+                       PinName misoPin,
+                       PinName sckPin,
+                       PinName csPin,
+                       unsigned maxSpeed)
+    : _spi(mosiPin, misoPin, sckPin),
+      _cs(csPin, 1)
+{
+    _cbEvent = 0;
+    _cbFired = false;
+    _callback.attach(this, &SpiContext::_cbHandler);
+
+    _spi.format(ADI_SENSE_SPI_FRAME_SIZE, ADI_SENSE_SPI_MODE);
+    _spi.frequency(maxSpeed);
+}
+
+void SpiContext::_cbHandler(int event)
+{
+    _cbEvent = event;
+    _cbFired = true;
+}
+
+int SpiContext::_waitForCallback(void)
+{
+    int rc = 0;
+
+    while ((_cbFired != true) && (_cbEvent != SPI_EVENT_COMPLETE))
+    { ; }
+
+    _cbFired = false;
+    _cbEvent = 0;
+
+    return rc;
+}
+
+int SpiContext::transfer(
+    void *pTxData,
+    void *pRxData,
+    unsigned nLength,
+    bool bCsHold)
+{
+    int rc = 0;
+
+    _cs = 0;
+
+    rc  = _spi.transfer((uint8_t *)pTxData, nLength,
+                        (uint8_t *)pRxData, nLength,
+                        _callback, SPI_EVENT_COMPLETE);
+    if (rc < 0)
+    {
+        _cs = 1;
+        return rc;
+    }   
+
+    rc = _waitForCallback();
+    if ((rc < 0) || !bCsHold)
+        _cs = 1;
+
+    return rc;
+}
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Open the SPI interface and allocate resources
+ */
+ADI_SENSE_RESULT adi_sense_SpiOpen(
+    ADI_SENSE_PLATFORM_SPI_CONFIG *pConfig,
+    ADI_SENSE_SPI_HANDLE *phDevice)
+{
+    SpiContext *pCtx = new SpiContext((PinName)pConfig->mosiPin,
+                                      (PinName)pConfig->misoPin,
+                                      (PinName)pConfig->sckPin,
+                                      (PinName)pConfig->csPin,
+                                      pConfig->maxSpeedHz);
+    if (!pCtx)
+    {
+        ADI_SENSE_LOG_ERROR("Failed to allocate memory for SPI interface");
+        return ADI_SENSE_NO_MEM;
+    }
+
+    *phDevice = reinterpret_cast<ADI_SENSE_SPI_HANDLE>(pCtx);
+    return ADI_SENSE_SUCCESS;
+}
+
+/*
+ * Execute a bi-directional data transfer on the SPI interface
+ */
+ADI_SENSE_RESULT
+adi_sense_SpiTransfer(
+    ADI_SENSE_SPI_HANDLE hDevice,
+    void *pTxData,
+    void *pRxData,
+    unsigned nLength,
+    bool bCsHold)
+{
+    SpiContext *pCtx = reinterpret_cast<SpiContext *>(hDevice);
+
+    if (pCtx->transfer(pTxData, pRxData, nLength, bCsHold) < 0)
+    {
+        ADI_SENSE_LOG_ERROR("Failed to complete SPI transfer");
+        return ADI_SENSE_FAILURE;
+    }
+
+    return ADI_SENSE_SUCCESS;
+}
+
+/*
+ * Close the SPI interface and free resources
+ */
+void adi_sense_SpiClose(
+    ADI_SENSE_SPI_HANDLE hDevice)
+{
+    SpiContext *pCtx = reinterpret_cast<SpiContext *>(hDevice);
+
+    delete pCtx;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+/*!
+ * @}
+ */
+