Messages in this thread | | | Date | Fri, 30 May 2014 17:01:30 +0800 | From | Huang Shijie <> | Subject | Re: [PATCH 1/2] serial: imx: remove the DMA wait queue |
| |
On Fri, May 30, 2014 at 09:27:20AM +0000, Wang, Jiada (ESD) wrote: > Hi Shijie > > After apply this patch into our kernel, > We are facing data hang issue when sending big size file (2M used in test) to uart port > Note: Rx port is also keep receiving data. > > After read the implementation of uart_stop(), > I feel like, stop_tx() is used to perform flow control when like a XOFF is received. > Which means no data should be dropped, as they may need to be sent out, > When next start_tx() is called. > > But by calling dmaengine_termiate_all(), the data already be submitted to DMA engine, > May be lost, thus cause data hang. > > What do you think? This patch has been reverted by Greg.
I also noticed the data loss issue.
thanks Huang Shijie
| |