From bf18723d50206a0b485e438f14c22faf91a3908f Mon Sep 17 00:00:00 2001 From: Alban Browaeys Date: Sun, 28 Feb 2010 17:14:40 +0100 Subject: [PATCH] rt2x00: Fix TX status reporting for rt2800pci. After testing, we found that TX_STA_FIFO_MCS is the last MCS value tried. If the transmission failed, 8 frames have been transmitted. If the transmission succeed, we can easily compute the number of retry. This patch fix the way status is reported to mac80211 rate control. It has 2 bugs : 1. mcs can contain the short preamble flag and it will lead to wrong computations. 2. minstrel nearly always say that 54 Mbits is the best rate, even if we are very far from the AP Signed-off-by: Benoit Papillault Signed-off-by: Alban Browaeys Acked-by: Ivo van Doorn Signed-off-by: Gertjan van Wingerde Signed-off-by: John W. Linville --- drivers/net/wireless/rt2x00/rt2800pci.c | 40 +++++++++++++++---------- 1 file changed, 25 insertions(+), 15 deletions(-) diff --git a/drivers/net/wireless/rt2x00/rt2800pci.c b/drivers/net/wireless/rt2x00/rt2800pci.c index 2f42e01eb99d..b1f5643f83fc 100644 --- a/drivers/net/wireless/rt2x00/rt2800pci.c +++ b/drivers/net/wireless/rt2x00/rt2800pci.c @@ -974,26 +974,36 @@ static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev) * Obtain the status about this packet. */ txdesc.flags = 0; - if (rt2x00_get_field32(reg, TX_STA_FIFO_TX_SUCCESS)) - __set_bit(TXDONE_SUCCESS, &txdesc.flags); - else - __set_bit(TXDONE_FAILURE, &txdesc.flags); + rt2x00_desc_read(txwi, 0, &word); + mcs = rt2x00_get_field32(word, TXWI_W0_MCS); + real_mcs = rt2x00_get_field32(reg, TX_STA_FIFO_MCS); /* * Ralink has a retry mechanism using a global fallback - * table. We setup this fallback table to try immediate - * lower rate for all rates. In the TX_STA_FIFO, - * the MCS field contains the MCS used for the successfull - * transmission. If the first transmission succeed, - * we have mcs == tx_mcs. On the second transmission, - * we have mcs = tx_mcs - 1. So the number of - * retry is (tx_mcs - mcs). + * table. We setup this fallback table to try the immediate + * lower rate for all rates. In the TX_STA_FIFO, the MCS field + * always contains the MCS used for the last transmission, be + * it successful or not. */ - rt2x00_desc_read(txwi, 0, &word); - mcs = rt2x00_get_field32(word, TXWI_W0_MCS); - real_mcs = rt2x00_get_field32(reg, TX_STA_FIFO_MCS); + if (rt2x00_get_field32(reg, TX_STA_FIFO_TX_SUCCESS)) { + /* + * Transmission succeeded. The number of retries is + * mcs - real_mcs + */ + __set_bit(TXDONE_SUCCESS, &txdesc.flags); + txdesc.retry = ((mcs > real_mcs) ? mcs - real_mcs : 0); + } else { + /* + * Transmission failed. The number of retries is + * always 7 in this case (for a total number of 8 + * frames sent). + */ + __set_bit(TXDONE_FAILURE, &txdesc.flags); + txdesc.retry = 7; + } + __set_bit(TXDONE_FALLBACK, &txdesc.flags); - txdesc.retry = mcs - min(mcs, real_mcs); + rt2x00lib_txdone(entry, &txdesc); } -- GitLab