Get rid of spurious "subdevice does not support commands" warnings.

diff --git a/demo/info.c b/demo/info.c
index bc99af1efae0d6f25988a9c5cd6b42c91af332cf..7b3b7e21486b71d9b9548cb395feaedc976cb0e1 100644 (file)
--- a/demo/info.c
+++ b/demo/info.c
@@ -123,6 +123,10 @@ int comedi_get_cmd_src_mask(comedi_t *it,unsigned int s,comedi_cmd *cmd)
 {
        memset(cmd,0,sizeof(*cmd));
 
+       if(!(comedi_get_subdevice_flags(it,s)&SDF_CMD)){
+               return -1;
+       }
+
        cmd->subdev = s;
 
        cmd->flags = 0;
@@ -141,7 +145,8 @@ int comedi_get_cmd_fast_1chan(comedi_t *it,unsigned int s,comedi_cmd *cmd)
 {
        int ret;
 
-       comedi_get_cmd_src_mask(it,s,cmd);
+       ret = comedi_get_cmd_src_mask(it,s,cmd);
+       if(ret<0)return ret;
 
        cmd->chanlist_len = 1;