| Message ID | 1524537824-22010-3-git-send-email-william.wu@rock-chips.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hello! On 4/24/2018 5:43 AM, William Wu wrote: > If isoc split in transfer with no data (the length of DATA0 > packet is 0), we can't simply return immediately. Because the > DATA0 can be the first transaction or the second transaction for > the isoc split in transaction. If the DATA0 packet with on data ^^ no? > is in the first transaction, we can return immediately. But if > the the DATA0 packet with on data is in the second transaction One "the" too many. And that "on data" again... :-) > of isoc split in transaction sequence, we need to increase the > qtd->isoc_frame_index and giveback urb to device driver if needed, > otherwise, the MDATA packet will be lost. > > A typical test case is that connect the dwc2 controller with an > usb hs Hub (GL852G-12), and plug an usb fs audio device (Plantronics > headset) into the downstream port of Hub. Then use the usb mic > to record, we can find noise when playback. > > In the case, the isoc split in transaction sequence like this: > > - SSPLIT IN transaction > - CSPLIT IN transaction > - MDATA packet (176 bytes) > - CSPLIT IN transaction > - DATA0 packet (0 byte) > > This patch use both the length of DATA0 and qtd->isoc_split_offset > to check if the DATA0 is in the second transaction. > > Signed-off-by: William Wu <william.wu@rock-chips.com> [...] MBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Dear Sergei, 在 2018年04月24日 16:27, Sergei Shtylyov 写道: > Hello! > > On 4/24/2018 5:43 AM, William Wu wrote: > >> If isoc split in transfer with no data (the length of DATA0 >> packet is 0), we can't simply return immediately. Because the >> DATA0 can be the first transaction or the second transaction for >> the isoc split in transaction. If the DATA0 packet with on data > ^^ no? Thank you for correcting me. I will fix it in next patch version. > >> is in the first transaction, we can return immediately. But if >> the the DATA0 packet with on data is in the second transaction > > One "the" too many. And that "on data" again... :-) Ah, sorry to make such a simple mistake. I will fix these in next patch version. > >> of isoc split in transaction sequence, we need to increase the >> qtd->isoc_frame_index and giveback urb to device driver if needed, >> otherwise, the MDATA packet will be lost. >> >> A typical test case is that connect the dwc2 controller with an >> usb hs Hub (GL852G-12), and plug an usb fs audio device (Plantronics >> headset) into the downstream port of Hub. Then use the usb mic >> to record, we can find noise when playback. >> >> In the case, the isoc split in transaction sequence like this: >> >> - SSPLIT IN transaction >> - CSPLIT IN transaction >> - MDATA packet (176 bytes) >> - CSPLIT IN transaction >> - DATA0 packet (0 byte) >> >> This patch use both the length of DATA0 and qtd->isoc_split_offset >> to check if the DATA0 is in the second transaction. >> >> Signed-off-by: William Wu <william.wu@rock-chips.com> > [...] > > MBR, Sergei Best regards, wulf > > > -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/usb/dwc2/hcd_intr.c b/drivers/usb/dwc2/hcd_intr.c index 5e2378f..479f628 100644 --- a/drivers/usb/dwc2/hcd_intr.c +++ b/drivers/usb/dwc2/hcd_intr.c @@ -930,7 +930,7 @@ static int dwc2_xfercomp_isoc_split_in(struct dwc2_hsotg *hsotg, frame_desc = &qtd->urb->iso_descs[qtd->isoc_frame_index]; len = dwc2_get_actual_xfer_length(hsotg, chan, chnum, qtd, DWC2_HC_XFER_COMPLETE, NULL); - if (!len) { + if (!len && !qtd->isoc_split_offset) { qtd->complete_split = 0; qtd->isoc_split_offset = 0; return 0;
If isoc split in transfer with no data (the length of DATA0 packet is 0), we can't simply return immediately. Because the DATA0 can be the first transaction or the second transaction for the isoc split in transaction. If the DATA0 packet with on data is in the first transaction, we can return immediately. But if the the DATA0 packet with on data is in the second transaction of isoc split in transaction sequence, we need to increase the qtd->isoc_frame_index and giveback urb to device driver if needed, otherwise, the MDATA packet will be lost. A typical test case is that connect the dwc2 controller with an usb hs Hub (GL852G-12), and plug an usb fs audio device (Plantronics headset) into the downstream port of Hub. Then use the usb mic to record, we can find noise when playback. In the case, the isoc split in transaction sequence like this: - SSPLIT IN transaction - CSPLIT IN transaction - MDATA packet (176 bytes) - CSPLIT IN transaction - DATA0 packet (0 byte) This patch use both the length of DATA0 and qtd->isoc_split_offset to check if the DATA0 is in the second transaction. Signed-off-by: William Wu <william.wu@rock-chips.com> --- drivers/usb/dwc2/hcd_intr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)