1 files changed, 98 insertions, 4 deletions

diff --git a/tools/iio/generic_buffer.c b/tools/iio/generic_buffer.c
index c42b7f836b48..2429c78de940 100644
--- a/tools/iio/generic_buffer.c
+++ b/tools/iio/generic_buffer.c
@@ -35,6 +35,15 @@
 #include "iio_utils.h"
 
 /**
+ * enum autochan - state for the automatic channel enabling mechanism
+ */
+enum autochan {
+        AUTOCHANNELS_DISABLED,
+        AUTOCHANNELS_ENABLED,
+        AUTOCHANNELS_ACTIVE,
+};
+
+/**
  * size_from_channelarray() - calculate the storage size of a scan
  * @channels:           the channel info array
  * @num_channels:       number of channels
@@ -191,10 +200,51 @@ void process_scan(char *data,
         printf("\n");
 }
 
+static int enable_disable_all_channels(char *dev_dir_name, int enable)
+{
+        const struct dirent *ent;
+        char scanelemdir[256];
+        DIR *dp;
+        int ret;
+
+        snprintf(scanelemdir, sizeof(scanelemdir),
+                 FORMAT_SCAN_ELEMENTS_DIR, dev_dir_name);
+        scanelemdir[sizeof(scanelemdir)-1] = '\0';
+
+        dp = opendir(scanelemdir);
+        if (!dp) {
+                fprintf(stderr, "Enabling/disabling channels: can't open %s\n",
+                        scanelemdir);
+                return -EIO;
+        }
+
+        ret = -ENOENT;
+        while (ent = readdir(dp), ent) {
+                if (iioutils_check_suffix(ent->d_name, "_en")) {
+                        printf("%sabling: %s\n",
+                               enable ? "En" : "Dis",
+                               ent->d_name);
+                        ret = write_sysfs_int(ent->d_name, scanelemdir,
+                                              enable);
+                        if (ret < 0)
+                                fprintf(stderr, "Failed to enable/disable %s\n",
+                                        ent->d_name);
+                }
+        }
+
+        if (closedir(dp) == -1) {
+                perror("Enabling/disabling channels: "
+                       "Failed to close directory");
+                return -errno;
+        }
+        return 0;
+}
+
 void print_usage(void)
 {
         fprintf(stderr, "Usage: generic_buffer [options]...\n"
                 "Capture, convert and output data from IIO device buffer\n"
+                "  -a         Auto-activate all available channels\n"
                 "  -c <n>     Do n conversions\n"
                 "  -e         Disable wait for event (new data)\n"
                 "  -g         Use trigger-less mode\n"
@@ -225,12 +275,16 @@ int main(int argc, char **argv)
         int scan_size;
         int noevents = 0;
         int notrigger = 0;
+        enum autochan autochannels = AUTOCHANNELS_DISABLED;
         char *dummy;
 
         struct iio_channel_info *channels;
 
-        while ((c = getopt(argc, argv, "c:egl:n:t:w:")) != -1) {
+        while ((c = getopt(argc, argv, "ac:egl:n:t:w:")) != -1) {
                 switch (c) {
+                case 'a':
+                        autochannels = AUTOCHANNELS_ENABLED;
+                        break;
                 case 'c':
                         errno = 0;
                         num_loops = strtoul(optarg, &dummy, 10);
@@ -340,12 +394,47 @@ int main(int argc, char **argv)
                         "diag %s\n", dev_dir_name);
                 goto error_free_triggername;
         }
-        if (!num_channels) {
+        if (num_channels && autochannels == AUTOCHANNELS_ENABLED) {
+                fprintf(stderr, "Auto-channels selected but some channels "
+                        "are already activated in sysfs\n");
+                fprintf(stderr, "Proceeding without activating any channels\n");
+        }
+
+        if (!num_channels && autochannels == AUTOCHANNELS_ENABLED) {
+                fprintf(stderr,
+                        "No channels are enabled, enabling all channels\n");
+
+                ret = enable_disable_all_channels(dev_dir_name, 1);
+                if (ret) {
+                        fprintf(stderr, "Failed to enable all channels\n");
+                        goto error_free_triggername;
+                }
+
+                /* This flags that we need to disable the channels again */
+                autochannels = AUTOCHANNELS_ACTIVE;
+
+                ret = build_channel_array(dev_dir_name, &channels,
+                                          &num_channels);
+                if (ret) {
+                        fprintf(stderr, "Problem reading scan element "
+                                "information\n"
+                                "diag %s\n", dev_dir_name);
+                        goto error_disable_channels;
+                }
+                if (!num_channels) {
+                        fprintf(stderr, "Still no channels after "
+                                "auto-enabling, giving up\n");
+                        goto error_disable_channels;
+                }
+        }
+
+        if (!num_channels && autochannels == AUTOCHANNELS_DISABLED) {
                 fprintf(stderr,
                         "No channels are enabled, we have nothing to scan.\n");
                 fprintf(stderr, "Enable channels manually in "
                         FORMAT_SCAN_ELEMENTS_DIR
-                        "/*_en and try again.\n", dev_dir_name);
+                        "/*_en or pass -a to autoenable channels and "
+                        "try again.\n", dev_dir_name);
                 ret = -ENOENT;
                 goto error_free_triggername;
         }
@@ -479,7 +568,12 @@ error_free_channels:
 error_free_triggername:
         if (datardytrigger)
                 free(trigger_name);
-
+error_disable_channels:
+        if (autochannels == AUTOCHANNELS_ACTIVE) {
+                ret = enable_disable_all_channels(dev_dir_name, 0);
+                if (ret)
+                        fprintf(stderr, "Failed to disable all channels\n");
+        }
 error_free_dev_dir_name:
         free(dev_dir_name);