On Tue, Jul 13, 2010 at 9:15 PM, Helmut Schaa <helmut.schaa@xxxxxxxxxxxxxx> wrote: > Am Dienstag 13 Juli 2010 schrieb Ivo Van Doorn: >> On Mon, Jul 12, 2010 at 9:14 PM, Helmut Schaa >> <helmut.schaa@xxxxxxxxxxxxxx> wrote: >> > Am Montag 12 Juli 2010 schrieb Ivo Van Doorn: >> >> I am currently looking into the old problem of the mac80211 rate >> >> control algorithms >> >> and USB devices. The Ralink USB devices (and as far as I know, the >> >> other USB devices >> >> as well), do not work well with the PID and Minstrel algorithms. This >> >> is caused by the >> >> fact that USB devices do not report the TX status to mac80211. >> > >> > Ivo, do you know by any chance if the USB devices also have a TX_STA_FIFO >> > register like the PCI variants? Does it contain useful data or just crap? >> >> Well I guess he has the registers (we don't have rt2870 specific specsheets, >> but the register definitions from the original Ralink driver to >> suggest the register >> is there). However, even if it contains valid data, how do you want to match >> the contents of that register with the sent frames in the queue? > > We could stuff a unique packet ID into the TXWI and the TX_STA_FIFO should > contain the same ID alongside the TX status after the frame was processed > by the hw. True, but we would have the same problem in rt2800pci, that the number of bits is too limited to completely identify a queue + queue index correctly. >> And another downside, is that the above only applies to rt2800usb, and not >> for rt73usb and rt2500usb, which neither have the TX status register, and were >> replaced with statistics registers (which I want to read for the batch >> TX status). > > Ok, that's a valid argument ... :) Ivo -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
