Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck...
[firefly-linux-kernel-4.4.55.git] / tools / iio / generic_buffer.c
index 4eebb6616e5ca33aca62a036db63c4a38a5fad61..9f7b85bf6ada3e3cdf43508ab9b3589daf14325a 100644 (file)
@@ -51,14 +51,33 @@ int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
                if (bytes % channels[i].bytes == 0)
                        channels[i].location = bytes;
                else
-                       channels[i].location = bytes - bytes%channels[i].bytes
-                               + channels[i].bytes;
+                       channels[i].location = bytes - bytes % channels[i].bytes
+                                              + channels[i].bytes;
+
                bytes = channels[i].location + channels[i].bytes;
                i++;
        }
+
        return bytes;
 }
 
+void print1byte(uint8_t input, struct iio_channel_info *info)
+{
+       /*
+        * Shift before conversion to avoid sign extension
+        * of left aligned data
+        */
+       input >>= info->shift;
+       input &= info->mask;
+       if (info->is_signed) {
+               int8_t val = (int8_t)(input << (8 - info->bits_used)) >>
+                            (8 - info->bits_used);
+               printf("%05f ", ((float)val + info->offset) * info->scale);
+       } else {
+               printf("%05f ", ((float)input + info->offset) * info->scale);
+       }
+}
+
 void print2byte(uint16_t input, struct iio_channel_info *info)
 {
        /* First swap if incorrect endian */
@@ -136,9 +155,9 @@ void print8byte(uint64_t input, struct iio_channel_info *info)
 /**
  * process_scan() - print out the values in SI units
  * @data:              pointer to the start of the scan
- * @channels:          information about the channels. Note
- *  size_from_channelarray must have been called first to fill the
- *  location offsets.
+ * @channels:          information about the channels.
+ *                     Note: size_from_channelarray must have been called first
+ *                           to fill the location offsets.
  * @num_channels:      number of channels
  **/
 void process_scan(char *data,
@@ -150,6 +169,10 @@ void process_scan(char *data,
        for (k = 0; k < num_channels; k++)
                switch (channels[k].bytes) {
                        /* only a few cases implemented so far */
+               case 1:
+                       print1byte(*(uint8_t *)(data + channels[k].location),
+                                  &channels[k]);
+                       break;
                case 2:
                        print2byte(*(uint16_t *)(data + channels[k].location),
                                   &channels[k]);
@@ -170,15 +193,15 @@ void process_scan(char *data,
 
 void print_usage(void)
 {
-       printf("Usage: generic_buffer [options]...\n"
-              "Capture, convert and output data from IIO device buffer\n"
-              "  -c <n>     Do n conversions\n"
-              "  -e         Disable wait for event (new data)\n"
-              "  -g         Use trigger-less mode\n"
-              "  -l <n>     Set buffer length to n samples\n"
-              "  -n <name>  Set device name (mandatory)\n"
-              "  -t <name>  Set trigger name\n"
-              "  -w <n>     Set delay between reads in us (event-less mode)\n");
+       fprintf(stderr, "Usage: generic_buffer [options]...\n"
+               "Capture, convert and output data from IIO device buffer\n"
+               "  -c <n>     Do n conversions\n"
+               "  -e         Disable wait for event (new data)\n"
+               "  -g         Use trigger-less mode\n"
+               "  -l <n>     Set buffer length to n samples\n"
+               "  -n <name>  Set device name (mandatory)\n"
+               "  -t <name>  Set trigger name\n"
+               "  -w <n>     Set delay between reads in us (event-less mode)\n");
 }
 
 int main(int argc, char **argv)
@@ -213,6 +236,7 @@ int main(int argc, char **argv)
                        num_loops = strtoul(optarg, &dummy, 10);
                        if (errno)
                                return -errno;
+
                        break;
                case 'e':
                        noevents = 1;
@@ -225,6 +249,7 @@ int main(int argc, char **argv)
                        buf_len = strtoul(optarg, &dummy, 10);
                        if (errno)
                                return -errno;
+
                        break;
                case 'n':
                        device_name = optarg;
@@ -245,8 +270,8 @@ int main(int argc, char **argv)
                }
        }
 
-       if (device_name == NULL) {
-               printf("Device name not set\n");
+       if (!device_name) {
+               fprintf(stderr, "Device name not set\n");
                print_usage();
                return -1;
        }
@@ -254,9 +279,10 @@ int main(int argc, char **argv)
        /* Find the device requested */
        dev_num = find_type_by_name(device_name, "iio:device");
        if (dev_num < 0) {
-               printf("Failed to find the %s\n", device_name);
+               fprintf(stderr, "Failed to find the %s\n", device_name);
                return dev_num;
        }
+
        printf("iio device number being used is %d\n", dev_num);
 
        ret = asprintf(&dev_dir_name, "%siio:device%d", iio_dir, dev_num);
@@ -264,7 +290,7 @@ int main(int argc, char **argv)
                return -ENOMEM;
 
        if (!notrigger) {
-               if (trigger_name == NULL) {
+               if (!trigger_name) {
                        /*
                         * Build the trigger name. If it is device associated
                         * its name is <device_name>_dev[n] where n matches
@@ -281,13 +307,16 @@ int main(int argc, char **argv)
                /* Verify the trigger exists */
                trig_num = find_type_by_name(trigger_name, "trigger");
                if (trig_num < 0) {
-                       printf("Failed to find the trigger %s\n", trigger_name);
+                       fprintf(stderr, "Failed to find the trigger %s\n",
+                               trigger_name);
                        ret = trig_num;
                        goto error_free_triggername;
                }
+
                printf("iio trigger number being used is %d\n", trig_num);
-       } else
+       } else {
                printf("trigger-less mode selected\n");
+       }
 
        /*
         * Parse the files in scan_elements to identify what channels are
@@ -295,8 +324,8 @@ int main(int argc, char **argv)
         */
        ret = build_channel_array(dev_dir_name, &channels, &num_channels);
        if (ret) {
-               printf("Problem reading scan element information\n");
-               printf("diag %s\n", dev_dir_name);
+               fprintf(stderr, "Problem reading scan element information\n"
+                       "diag %s\n", dev_dir_name);
                goto error_free_triggername;
        }
 
@@ -314,13 +343,16 @@ int main(int argc, char **argv)
 
        if (!notrigger) {
                printf("%s %s\n", dev_dir_name, trigger_name);
-               /* Set the device trigger to be the data ready trigger found
-                * above */
+               /*
+                * Set the device trigger to be the data ready trigger found
+                * above
+                */
                ret = write_sysfs_string_and_verify("trigger/current_trigger",
                                                    dev_dir_name,
                                                    trigger_name);
                if (ret < 0) {
-                       printf("Failed to write current_trigger file\n");
+                       fprintf(stderr,
+                               "Failed to write current_trigger file\n");
                        goto error_free_buf_dir_name;
                }
        }
@@ -332,10 +364,14 @@ int main(int argc, char **argv)
 
        /* Enable the buffer */
        ret = write_sysfs_int("enable", buf_dir_name, 1);
-       if (ret < 0)
+       if (ret < 0) {
+               fprintf(stderr,
+                       "Failed to enable buffer: %s\n", strerror(-ret));
                goto error_free_buf_dir_name;
+       }
+
        scan_size = size_from_channelarray(channels, num_channels);
-       data = malloc(scan_size*buf_len);
+       data = malloc(scan_size * buf_len);
        if (!data) {
                ret = -ENOMEM;
                goto error_free_buf_dir_name;
@@ -349,13 +385,12 @@ int main(int argc, char **argv)
 
        /* Attempt to open non blocking the access dev */
        fp = open(buffer_access, O_RDONLY | O_NONBLOCK);
-       if (fp == -1) { /* If it isn't there make the node */
+       if (fp == -1) { /* TODO: If it isn't there make the node */
                ret = -errno;
-               printf("Failed to open %s\n", buffer_access);
+               fprintf(stderr, "Failed to open %s\n", buffer_access);
                goto error_free_buffer_access;
        }
 
-       /* Wait for events 10 times */
        for (j = 0; j < num_loops; j++) {
                if (!noevents) {
                        struct pollfd pfd = {
@@ -372,25 +407,22 @@ int main(int argc, char **argv)
                        }
 
                        toread = buf_len;
-
                } else {
                        usleep(timedelay);
                        toread = 64;
                }
 
-               read_size = read(fp,
-                                data,
-                                toread*scan_size);
+               read_size = read(fp, data, toread * scan_size);
                if (read_size < 0) {
                        if (errno == EAGAIN) {
-                               printf("nothing available\n");
+                               fprintf(stderr, "nothing available\n");
                                continue;
-                       } else
+                       } else {
                                break;
+                       }
                }
-               for (i = 0; i < read_size/scan_size; i++)
-                       process_scan(data + scan_size*i,
-                                    channels,
+               for (i = 0; i < read_size / scan_size; i++)
+                       process_scan(data + scan_size * i, channels,
                                     num_channels);
        }
 
@@ -404,11 +436,13 @@ int main(int argc, char **argv)
                ret = write_sysfs_string("trigger/current_trigger",
                                         dev_dir_name, "NULL");
                if (ret < 0)
-                       printf("Failed to write to %s\n", dev_dir_name);
+                       fprintf(stderr, "Failed to write to %s\n",
+                               dev_dir_name);
 
 error_close_buffer_access:
        if (close(fp) == -1)
                perror("Failed to close buffer");
+
 error_free_buffer_access:
        free(buffer_access);
 error_free_data:
@@ -424,6 +458,7 @@ error_free_channels:
 error_free_triggername:
        if (datardytrigger)
                free(trigger_name);
+
 error_free_dev_dir_name:
        free(dev_dir_name);