Hi Laurent Pinchart, Sorry for the delay in the reply. Thanks for the review... > > Hi Kedar, > > On Monday 19 Dec 2016 15:39:43 Appana Durga Kedareswara Rao wrote: > > Hi Laurent Pinchart, > > > > Thanks for the review... > > > > > > + if (!chan->idle) > > > > + return; > > > > > > Don't you need to perform the same check for the DMA and CDMA channels > ? > > > If so, shouldn't this be moved to common code ? > > > > Will fix it in v2... > > > > > There's another problem (not strictly introduced by this patch) I > > > wanted to mention. The append_desc_queue() function, called from > > > your tx_submit handler, appends descriptors to the pending_list. The > > > DMA engine API states that a transfer submitted by tx_submit will > > > not be executed until > > > .issue_pending() is called. However, if a transfer is in progress at > > > tx_submit time, I believe that the IRQ handler, at transfer > > > completion, will start the next transfer from the pending_list even > > > if > > > .issue_pending() hasn't been called for it. > > > > > > > if (list_empty(&chan->pending_list)) > > > > return; > > > > If user submits more than h/w limit then that case only driver will > > process The descriptors from the pending_list for other cases the > > pending_list will be Empty so driver just returns from there. > > I understand that, but that's not the problem. Your .tx_submit() handler calls > append_desc_queue() which adds the tx descriptor to the pending_list. If a > transfer is in progress at that time, I believe the transfer completion IRQ handler > will take the next descriptor from the pending_list and process it, even though > issue_pending() hasn't been called for it. > Thanks for the explanation... Agree will keep this my to-do list... Regards, Kedar. -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
