Add bargraph app

README.md

@@ -18,13 +18,22 @@ After starting the app move your hand above the motion click.
 
 Press ctrl+c to exit the application.
 
-Two options can be given:
-
-1) mikroBUS number to specify where motion click is connected.
+mikroBUS number can be given in option to specify where motion click is connected.
 
 Default value for [mikroBUS](http://www.mikroe.com/mikrobus/) is 1
 
     $ motion_click_app -m <mikroBUS>
 
     Ready for detecting motion...
     detected
+
+###Application to display binary representation of a number using [bargraph click](http://www.mikroe.com/click/bargraph/)
+
+Start the app and enter number to display.
+
+mikroBUS number can be given in option to specify where bargraph click is connected.
+
+    $ bargraph_click_app -m <mikroBUS>
+
+    Enter number to display (0 for exit): 2
+    Enter number to display (0 for exit): 5

src/CMakeLists.txt

@@ -1,9 +1,13 @@
 # Add executable targets
 ########################
 ADD_LIBRARY(gpio OBJECT gpio.c)
+ADD_LIBRARY(spi_common OBJECT spi_common.c)
+ADD_LIBRARY(pwm_common OBJECT pwm_common.c)
+
 ADD_EXECUTABLE(motion_click_app motion_click_app.c $<TARGET_OBJECTS:gpio>)
+ADD_EXECUTABLE(bargraph_click_app bargraph_click_app.c $<TARGET_OBJECTS:spi_common> $<TARGET_OBJECTS:pwm_common>)
 
 # Add install targets
 ######################
-INSTALL(TARGETS motion_click_app
+INSTALL(TARGETS motion_click_app bargraph_click_app
 		RUNTIME DESTINATION /usr/bin)

src/bargraph_click_app.c

@@ -0,0 +1,180 @@
+/***************************************************************************************************
+ * Copyright (c) 2016, Imagination Technologies Limited and/or its affiliated group companies
+ * and/or licensors
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are permitted
+ * provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this list of conditions
+ *    and the following disclaimer.
+ *
+ * 2. 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.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its contributors may be used to
+ *    endorse or promote products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, 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 <stdio.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <linux/spi/spidev.h>
+#include <sys/ioctl.h>
+#include <string.h>
+#include <stdbool.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <fcntl.h>
+#include "spi_common.h"
+#include "pwm_common.h"
+
+/* bottom 10 bits of display_seg argument correspond to 10 display segments */
+static int send_to_bargraph(int fd, unsigned int display_seg)
+{
+    int ret;
+    unsigned int buf[2];
+    struct spi_ioc_transfer tr[2];
+
+    /* buf[0] will be shifted into segments 8 and 9 */
+    buf[0] = (display_seg >> 8) & 3;
+    /* buf[1] sets segments 0 to 7 */
+    buf[1] = display_seg & 0x00ff;
+
+    /* send message consisting of two transfers */
+    memset(&tr, 0, sizeof(tr));
+    tr[0].tx_buf = (unsigned long)&buf[0];
+    tr[0].len = 1;
+    tr[1].tx_buf = (unsigned long)&buf[1];
+    tr[1].len = 1;
+    ret = ioctl(fd, SPI_IOC_MESSAGE(2), &tr);
+
+    if (ret == -1)
+    {
+        perror("SPI error: can't send data\n");
+        return -1;
+    }
+
+    return 0;
+}
+
+static void PrintUsage(const char *program)
+{
+    printf("Usage: %s [options]\n\n"
+        " -m  <arg>  mikroBUS number\n"
+        " -h         display this message\n\n",
+        program);
+}
+
+static int ParseCmdOpts(int argc, char *argv[], char **spi_path)
+{
+    int opt;
+    uint8_t num;
+
+    opterr = 0;
+
+    while ((opt = getopt(argc, argv, "m:h")) != -1)
+    {
+        switch (opt)
+        {
+            case 'm':
+                num = strtoul(optarg, NULL, 10);
+                if (num != 1 && num != 2)
+                {
+                    fprintf(stderr, "Error: invalid mikroBUS\n");
+                    return -1;
+                }
+                *spi_path = SPI_PATH_FOR_MIKROBUS(num);
+                break;
+
+            case 'h':
+                PrintUsage(argv[0]);
+                return 0;
+
+            default:
+                PrintUsage(argv[0]);
+                return -1;
+        }
+    }
+    return 1;
+}
+
+static inline void clean_stdin()
+{
+    while (getchar()!='\n');
+}
+
+int main(int argc, char *argv[])
+{
+    int fd, status;
+    unsigned int num_to_display;
+    char *spi_path = SPI_PATH_FOR_MIKROBUS(1);
+    char c;
+
+    status = ParseCmdOpts(argc, argv, &spi_path);
+    if (status <= 0)
+    {
+        return status;
+    }
+
+    fd = SpiInit(spi_path);
+    if (fd < 0)
+    {
+        return -1;
+    }
+
+    status = PwmExport(0);
+    if (status == -1)
+    {
+        goto cleanup;
+    }
+    status = PwmPeriod(0, 100000);
+    if (status == -1)
+    {
+        goto cleanup;
+    }
+    status = PwmDutyCycle(0, 50000);
+    if (status == -1)
+    {
+        goto cleanup;
+    }
+    status = PwmEnable(0);
+    if (status == -1)
+    {
+        goto cleanup;
+    }
+
+    // clear all segments
+    send_to_bargraph(fd, 0);
+
+    while (1)
+    {
+        printf("\nEnter number to display (0 for exit): ");
+        fflush(stdout);
+        if (scanf("%u%c", &num_to_display, &c) != 2 || c != '\n')
+            clean_stdin();
+        if (num_to_display == 0)
+            break;
+        send_to_bargraph(fd, num_to_display);
+    }
+
+cleanup:
+    send_to_bargraph(fd, 0);
+    PwmUnexport(0);
+    SpiFree(fd);
+    return status;
+}

src/pwm_common.c

@@ -0,0 +1,157 @@
+/***************************************************************************************************
+ * Copyright (c) 2016, Imagination Technologies Limited and/or its affiliated group companies
+ * and/or licensors
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are permitted
+ * provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this list of conditions
+ *    and the following disclaimer.
+ *
+ * 2. 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.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its contributors may be used to
+ *    endorse or promote products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, 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 <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#define PATH_MAX    64
+#define BUFFER_MAX  8
+
+int PwmExport(unsigned int pwmNumber)
+{
+    int fd;
+    int bytesWritten, status = 0;
+    char buffer[BUFFER_MAX];
+
+    fd = open("/sys/class/pwm/pwmchip0/export", O_WRONLY);
+    if (fd == -1)
+    {
+        fprintf(stderr, "Failed to open export for writing\n");
+        return -1;
+    }
+
+    bytesWritten = snprintf(buffer, BUFFER_MAX, "%u", pwmNumber);
+    status = write(fd, buffer, bytesWritten);
+    if (status == -1)
+    {
+        fprintf(stderr, "Failed to export pwm\n");
+    }
+    close(fd);
+    return 0;
+}
+
+int PwmUnexport(unsigned int pwmNumber)
+{
+    int fd;
+    int bytesWritten, status = 0;
+    char buffer[BUFFER_MAX];
+
+    fd = open("/sys/class/pwm/pwmchip0/unexport", O_WRONLY);
+    if (fd == -1)
+    {
+        fprintf(stderr, "Failed to open unexport for writing");
+        return -1;
+    }
+
+    bytesWritten = snprintf(buffer, BUFFER_MAX, "%u", pwmNumber);
+    status = write(fd, buffer, bytesWritten);
+    if (status == -1)
+    {
+        fprintf(stderr, "Failed to unexport pwm");
+    }
+
+    close(fd);
+    return status;
+}
+
+int PwmPeriod(unsigned int pwmNumber, unsigned int period)
+{
+    int fd;
+    char path[PATH_MAX];
+    char buffer[BUFFER_MAX];
+    int bytesWritten, status = 0;
+
+    snprintf(path, PATH_MAX, "/sys/class/pwm/pwmchip0/pwm%u/period", pwmNumber);
+    fd = open(path, O_WRONLY);
+    if (fd == -1)
+    {
+        fprintf(stderr, "Failed to open pwm direction for writing\n");
+        return -1;
+    }
+
+    bytesWritten = snprintf(buffer, BUFFER_MAX, "%u", period);
+    status = write(fd, buffer, bytesWritten);
+    if (status == -1)
+    {
+        fprintf(stderr, "Failed to set pwm period\n");
+    }
+    close(fd);
+    return status;
+}
+
+int PwmDutyCycle(unsigned int pwmNumber, unsigned int dutyCycle)
+{
+    int fd;
+    char path[PATH_MAX];
+    char buffer[BUFFER_MAX];
+    int bytesWritten, status = 0;
+
+    snprintf(path, PATH_MAX, "/sys/class/pwm/pwmchip0/pwm%u/duty_cycle", pwmNumber);
+    fd = open(path, O_WRONLY);
+    if (fd == -1)
+    {
+        fprintf(stderr, "Failed to open pwm duty_cycle for writing\n");
+        return -1;
+    }
+
+    bytesWritten = snprintf(buffer, BUFFER_MAX, "%u", dutyCycle);
+    status = write(fd, buffer, bytesWritten);
+    if (status == -1)
+    {
+        fprintf(stderr, "Failed to set pwm duty_cycle\n");
+    }
+    close(fd);
+    return status;
+}
+
+int PwmEnable(unsigned int pwmNumber)
+{
+    int fd;
+    int status = 0;
+    char path[PATH_MAX];
+
+    snprintf(path, PATH_MAX, "/sys/class/pwm/pwmchip0/pwm%u/enable", pwmNumber);
+    fd = open(path, O_WRONLY);
+    if (fd == -1)
+    {
+        fprintf(stderr, "Failed to open pwm enable for writing\n");
+        return -1;
+    }
+
+    status = write(fd, "1", sizeof("1"));
+    if (status == -1)
+    {
+        fprintf(stderr, "Failed to set pwm enable\n");
+    }
+    close(fd);
+    return status;
+}