korad-kaxxxxp: tweak first "give time to process" invocation

The give_device_time_to_process() routine unconditionally calculated
with a "time since last command transmission" value which may not have
been assigned to in the first invocation of a getter or setter.

Just don't sleep at all when nothing was sent before. Avoids a
dependency on implementation details of signed integer math.

diff --git a/src/hardware/korad-kaxxxxp/protocol.c b/src/hardware/korad-kaxxxxp/protocol.c
index 4f09dbc7c80e970ba99caf3bca2b612d6e252594..ce6032c84af086cca715cb768bbb2120498fdba1 100644 (file)
--- a/src/hardware/korad-kaxxxxp/protocol.c
+++ b/src/hardware/korad-kaxxxxp/protocol.c
@@ -155,6 +155,9 @@ static void give_device_time_to_process(struct dev_context *devc)
 {
        int64_t sleeping_time;
 
+       if (!devc->req_sent_at)
+               return;
+
        sleeping_time = devc->req_sent_at + (DEVICE_PROCESSING_TIME_MS * 1000);
        sleeping_time -= g_get_monotonic_time();