> -----Original Message----- > From: Sergei Shtylyov [mailto:sshtylyov@xxxxxxxxxxxxx] > Sent: Friday, August 28, 2009 2:53 PM > To: Gupta, Ajay Kumar > Cc: linux-usb@xxxxxxxxxxxxxxx; linux-omap@xxxxxxxxxxxxxxx; > felipe.balbi@xxxxxxxxx; david-b@xxxxxxxxxxx; Subbrathnam, Swaminathan; B, > Ravi > Subject: Re: [PATCH] musb: fix ISOC Tx programming for CPPI DMAs > > Hello. > > Ajay Kumar Gupta wrote: > > > Isochronous Tx DMA is getting programmed but never getting started > > for CPPI and TUSB DMAs and thus Isochronous Tx doesn't work. > > > > That's not true. We have tested and it doesn't work with current driver. Have you tested it and was it working for you ? > > > Fixing it by starting DMAs using musb_h_tx_dma_start(). > > > > Signed-off-by: Swaminathan S <swami.iyer@xxxxxx> > > Signed-off-by: Babu Ravi <ravibabu@xxxxxx> > > Signed-off-by: Ajay Kumar Gupta <ajay.gupta@xxxxxx> > > > > NAK. > > > diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c > > index cf94511..e3ab40a 100644 > > --- a/drivers/usb/musb/musb_host.c > > +++ b/drivers/usb/musb/musb_host.c > > @@ -1301,8 +1301,11 @@ void musb_host_tx(struct musb *musb, u8 epnum) > > return; > > } else if (usb_pipeisoc(pipe) && dma) { > > if (musb_tx_dma_program(musb->dma_controller, hw_ep, qh, urb, > > - offset, length)) > > + offset, length)) { > > + if (is_cppi_enabled() || tusb_dma_omap()) > > + musb_h_tx_dma_start(hw_ep); > > return; > > > > It will have been already started by this moment -- from > musb_start_urb() which is enough . Otherwise it wouldn't work, and I've > made sure it *does* work. This part is being done at musb_host_rx() doing next packet programming within same urb and *not* starting next urb. Thus musb_start_urb() doesn't come into this path. So it wouldn't start the DMAs. In case of PIO, it does load the FIFO and sets the TXPKTREADY. -Ajay > > WBR, Sergei > > -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
