mraa mock: Add SPI functionality

Signed-off-by: Alex Tereschenko <alext.mkrs@gmail.com>
Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

src/mock/mock_board_spi.c

@@ -0,0 +1,177 @@
+/*
+ * Author: Alex Tereschenko <alext.mkrs@gmail.com>
+ * Copyright (c) 2016 Alex Tereschenko.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#if defined(MSYS)
+#define __USE_LINUX_IOCTL_DEFS
+#endif
+#include <sys/ioctl.h>
+#if defined(MSYS)
+// There's no spidev.h on MSYS, so we need to provide our own,
+// and only *after* including ioctl.h as that one contains prerequisites.
+#include "linux/spi_kernel_headers.h"
+#else
+#include <linux/spi/spidev.h>
+#endif
+
+#include "common.h"
+#include "mock/mock_board_spi.h"
+
+mraa_result_t
+mraa_mock_spi_init_raw_replace(mraa_spi_context dev, unsigned int bus, unsigned int cs)
+{
+    dev->clock = MOCK_SPI_DEFAULT_FREQ;
+
+    if ((mraa_spi_mode(dev, MOCK_SPI_DEFAULT_MODE) != MRAA_SUCCESS) ||
+        (mraa_spi_lsbmode(dev, MOCK_SPI_DEFAULT_LSBMODE) != MRAA_SUCCESS) ||
+        (mraa_spi_bit_per_word(dev, MOCK_SPI_DEFAULT_BIT_PER_WORD) != MRAA_SUCCESS)) {
+        return MRAA_ERROR_INVALID_RESOURCE;
+    }
+
+    return MRAA_SUCCESS;
+}
+
+mraa_result_t
+mraa_mock_spi_stop_replace(mraa_spi_context dev)
+{
+    free(dev);
+    return MRAA_SUCCESS;
+}
+
+mraa_result_t
+mraa_mock_spi_bit_per_word_replace(mraa_spi_context dev, unsigned int bits)
+{
+    if (bits == 0) {
+        syslog(LOG_ERR, "spi: bit_per_word: Cannot set to zero");
+        return MRAA_ERROR_INVALID_PARAMETER;
+    }
+
+    dev->bpw = bits;
+    return MRAA_SUCCESS;
+}
+
+mraa_result_t
+mraa_mock_spi_lsbmode_replace(mraa_spi_context dev, mraa_boolean_t lsb)
+{
+    dev->lsb = lsb;
+    return MRAA_SUCCESS;
+}
+
+mraa_result_t
+mraa_mock_spi_mode_replace(mraa_spi_context dev, mraa_spi_mode_t mode)
+{
+    uint8_t spi_mode = 0;
+
+    switch (mode) {
+    case MRAA_SPI_MODE0:
+        spi_mode = SPI_MODE_0;
+        break;
+    case MRAA_SPI_MODE1:
+        spi_mode = SPI_MODE_1;
+        break;
+    case MRAA_SPI_MODE2:
+        spi_mode = SPI_MODE_2;
+        break;
+    case MRAA_SPI_MODE3:
+        spi_mode = SPI_MODE_3;
+        break;
+    default:
+        syslog(LOG_ERR, "spi: mode: Invalid SPI mode selected", mode);
+        return MRAA_ERROR_INVALID_PARAMETER;
+    }
+
+    dev->mode = spi_mode;
+    return MRAA_SUCCESS;
+}
+
+mraa_result_t
+mraa_mock_spi_frequency_replace(mraa_spi_context dev, int hz)
+{
+    if (hz <= 0) {
+        syslog(LOG_ERR, "spi: frequency: Cannot set to zero or negative");
+        return MRAA_ERROR_INVALID_PARAMETER;
+    }
+
+    dev->clock = hz;
+    return MRAA_SUCCESS;
+}
+
+int
+mraa_mock_spi_write_replace(mraa_spi_context dev, uint8_t data)
+{
+    return (int) (data ^ MOCK_SPI_REPLY_DATA_MODIFIER_BYTE);
+}
+
+int
+mraa_mock_spi_write_word_replace(mraa_spi_context dev, uint16_t data)
+{
+    return (int) (data ^ MOCK_SPI_REPLY_DATA_MODIFIER_WORD);
+}
+
+mraa_result_t
+mraa_mock_spi_transfer_buf_replace(mraa_spi_context dev, uint8_t* data, uint8_t* rxbuf, int length)
+{
+    if (data == NULL) {
+        syslog(LOG_ERR, "spi: transfer_buf: Incoming data is null, cannot proceed");
+        return MRAA_ERROR_INVALID_PARAMETER;
+    }
+
+    if (length <= 0) {
+        syslog(LOG_ERR, "spi: transfer_buf: Length given is equal to or less than zero, cannot proceed");
+        return MRAA_ERROR_INVALID_PARAMETER;
+    }
+
+    if (rxbuf != NULL) {
+        for (int i = 0; i < length; ++i) {
+            rxbuf[i] = data[i] ^ MOCK_SPI_REPLY_DATA_MODIFIER_BYTE;
+        }
+    }
+
+    return MRAA_SUCCESS;
+}
+
+mraa_result_t
+mraa_mock_spi_transfer_buf_word_replace(mraa_spi_context dev, uint16_t* data, uint16_t* rxbuf, int length)
+{
+    if (data == NULL) {
+        syslog(LOG_ERR, "spi: transfer_buf_word: Incoming data is null, cannot proceed");
+        return MRAA_ERROR_INVALID_PARAMETER;
+    }
+
+    if (length <= 0) {
+        syslog(LOG_ERR, "spi: transfer_buf_word: Length given is equal to or less than zero, cannot proceed");
+        return MRAA_ERROR_INVALID_PARAMETER;
+    }
+
+    if (rxbuf != NULL) {
+        // length is given in bytes, but arrays are comprised of words
+        for (int i = 0; i < (length / 2); ++i) {
+            rxbuf[i] = data[i] ^ MOCK_SPI_REPLY_DATA_MODIFIER_WORD;
+        }
+    }
+
+    return MRAA_SUCCESS;
+}