Hi Bin,
On Wed, Sep 24, 2014 at 01:55:14PM -0500, Bin Liu wrote:
> Hi Felipe and all,
>
> The musb driver musb_host_tx() has the following:
>
> 1244 /* with CPPI, DMA sometimes triggers "extra" irqs */
> 1245 if (!urb) {
> 1246 dev_dbg(musb->controller, "extra TX%d ready, csr
> %04x\n", epnum, tx_csr);
> 1247 return;
> 1248 }
>
> and
>
> 1321 /* second cppi case */
> 1322 if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
> 1323 dev_dbg(musb->controller, "extra TX%d ready, csr
> %04x\n", epnum, tx_csr);
> 1324 return;
> 1325 }
>
> which come with the very first commit of musb driver and never got
> changed. Is there any more information about the 'extra' irqs? and
> what is the 'second cppi case'?
I'm afraid the details of that were long after Dave B left us,
unfortunately. He was the only one dealing with MUSB on those early
phases.
> I ran into this problem and musb stops working after hits here.
>
> [13542.933563] musb-hdrc musb-hdrc.1: qh c261ad80 urb eec92bc0 dev4
> ep7in-bulk, hw_ep 2, c2599000/4096
> [13542.953552] musb-hdrc musb-hdrc.1: usbintr (0) epintr(4)
> [13542.953582] musb-hdrc musb-hdrc.1: extra TX2 ready, csr 0004
>
> I bet this 'extra TX2 ready' log is printed by the first case, because
> only RX2 is used in this test, and TX2 is never got used, so there
> should not be any urb in TX2 queue. I am still waiting for another
> test failure to confirm this, but I am trying to understand why TX2
> interrupt happened...which seems to be related RX2 request.
>
> Thanks for any help.
unfortunately no clue on what's going on :-(
--
balbi
Attachment:
signature.asc
Description: Digital signature
