hameg-hmo: Rephrase the channel constraints check (analog vs digital)

[libsigrok.git] / src / hardware / hameg-hmo / api.c

diff --git a/src/hardware/hameg-hmo/api.c b/src/hardware/hameg-hmo/api.c
index 00d57c5ef3a8d103877b11a041a9189b9dc469ba..f8fc644cbb2c99b4667451a9998a87a1b85c3059 100644 (file)
--- a/src/hardware/hameg-hmo/api.c
+++ b/src/hardware/hameg-hmo/api.c
@@ -592,34 +592,50 @@ static int hmo_check_channels(GSList *channels)
 {
        GSList *l;
        struct sr_channel *ch;
-       gboolean enabled_pod1, enabled_pod2, enabled_chan3, enabled_chan4;
+       gboolean enabled_chan[MAX_ANALOG_CHANNEL_COUNT];
+       gboolean enabled_pod[MAX_DIGITAL_GROUP_COUNT];
+       size_t idx;
 
-       enabled_pod1 = enabled_pod2 = enabled_chan3 = enabled_chan4 = FALSE;
+       /* Preset "not enabled" for all channels / pods. */
+       for (idx = 0; idx < ARRAY_SIZE(enabled_chan); idx++)
+               enabled_chan[idx] = FALSE;
+       for (idx = 0; idx < ARRAY_SIZE(enabled_pod); idx++)
+               enabled_pod[idx] = FALSE;
 
+       /*
+        * Determine which channels / pods are required for the caller's
+        * specified configuration.
+        */
        for (l = channels; l; l = l->next) {
                ch = l->data;
                switch (ch->type) {
                case SR_CHANNEL_ANALOG:
-                       if (ch->index == 2)
-                               enabled_chan3 = TRUE;
-                       else if (ch->index == 3)
-                               enabled_chan4 = TRUE;
+                       idx = ch->index;
+                       if (idx < ARRAY_SIZE(enabled_chan))
+                               enabled_chan[idx] = TRUE;
                        break;
                case SR_CHANNEL_LOGIC:
-                       if (ch->index < 8)
-                               enabled_pod1 = TRUE;
-                       else
-                               enabled_pod2 = TRUE;
+                       idx = ch->index / 8;
+                       if (idx < ARRAY_SIZE(enabled_pod))
+                               enabled_pod[idx] = TRUE;
                        break;
                default:
                        return SR_ERR;
                }
        }
 
-       if ((enabled_pod1 && enabled_chan3) ||
-           (enabled_pod2 && enabled_chan4))
+       /*
+        * Check for resource conflicts. Some channels can be either
+        * analog or digital, but never both at the same time.
+        *
+        * Note that the constraints might depend on the specific model.
+        * These tests might need some adjustment when support for more
+        * models gets added to the driver.
+        */
+       if (enabled_pod[0] && enabled_chan[2])
+               return SR_ERR;
+       if (enabled_pod[1] && enabled_chan[3])
                return SR_ERR;
-
        return SR_OK;
 }