rt2x00: Fix rt2800usb RX frame format and as such L2PAD

According to Ralink source code, the RX frame format is RXINFO + RXWI +
802.11 frame + RXD, including various padding. Before this patch, we
were using RXD + RXWI + 802.11 frame, so RXD was not correct.

Doing this, we fix the L2PAD bit which is now correctly set on received
frames.

Signed-off-by: Benoit Papillault <benoit.papillault@free.fr>
Acked-by: Ivo van Doorn <ivdoorn@gmail.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 27 insertions, 11 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2800usb.c b/drivers/net/wireless/rt2x00/rt2800usb.c
index 9c4412b42e5b..40295b454ff6 100644
--- a/drivers/net/wireless/rt2x00/rt2800usb.c
+++ b/drivers/net/wireless/rt2x00/rt2800usb.c
@@ -571,41 +571,57 @@ static void rt2800usb_fill_rxdone(struct queue_entry *entry,
 {
         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
         struct skb_frame_desc *skbdesc = get_skb_frame_desc(entry->skb);
-        __le32 *rxd = (__le32 *)entry->skb->data;
+        __le32 *rxi = (__le32 *)entry->skb->data;
         __le32 *rxwi;
-        u32 rxd0;
+        __le32 *rxd;
+        u32 rxi0;
         u32 rxwi0;
         u32 rxwi1;
         u32 rxwi2;
         u32 rxwi3;
+        u32 rxd0;
+        int rx_pkt_len;
+
+        /*
+         * RX frame format is :
+         * | RXINFO | RXWI | header | L2 pad | payload | pad | RXD | USB pad |
+         *          |<------------ rx_pkt_len -------------->|
+         */
+        rt2x00_desc_read(rxi, 0, &rxi0);
+        rx_pkt_len = rt2x00_get_field32(rxi0, RXINFO_W0_USB_DMA_RX_PKT_LEN);
+
+        rxwi = (__le32 *)(entry->skb->data + RXINFO_DESC_SIZE);
+
+        /*
+         * FIXME : we need to check for rx_pkt_len validity
+         */
+        rxd = (__le32 *)(entry->skb->data + RXINFO_DESC_SIZE + rx_pkt_len);
 
         /*
          * Copy descriptor to the skbdesc->desc buffer, making it safe from
          * moving of frame data in rt2x00usb.
          */
-        memcpy(skbdesc->desc, rxd, skbdesc->desc_len);
-        rxd = (__le32 *)skbdesc->desc;
-        rxwi = &rxd[RXINFO_DESC_SIZE / sizeof(__le32)];
+        memcpy(skbdesc->desc, rxi, skbdesc->desc_len);
 
         /*
          * It is now safe to read the descriptor on all architectures.
          */
-        rt2x00_desc_read(rxd, 0, &rxd0);
         rt2x00_desc_read(rxwi, 0, &rxwi0);
         rt2x00_desc_read(rxwi, 1, &rxwi1);
         rt2x00_desc_read(rxwi, 2, &rxwi2);
         rt2x00_desc_read(rxwi, 3, &rxwi3);
+        rt2x00_desc_read(rxd, 0, &rxd0);
 
-        if (rt2x00_get_field32(rxd0, RXINFO_W0_CRC_ERROR))
+        if (rt2x00_get_field32(rxd0, RXD_W0_CRC_ERROR))
                 rxdesc->flags |= RX_FLAG_FAILED_FCS_CRC;
 
         if (test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags)) {
                 rxdesc->cipher = rt2x00_get_field32(rxwi0, RXWI_W0_UDF);
                 rxdesc->cipher_status =
-                    rt2x00_get_field32(rxd0, RXINFO_W0_CIPHER_ERROR);
+                    rt2x00_get_field32(rxd0, RXD_W0_CIPHER_ERROR);
         }
 
-        if (rt2x00_get_field32(rxd0, RXINFO_W0_DECRYPTED)) {
+        if (rt2x00_get_field32(rxd0, RXD_W0_DECRYPTED)) {
                 /*
                  * Hardware has stripped IV/EIV data from 802.11 frame during
                  * decryption. Unfortunately the descriptor doesn't contain
@@ -620,10 +636,10 @@ static void rt2800usb_fill_rxdone(struct queue_entry *entry,
                         rxdesc->flags |= RX_FLAG_MMIC_ERROR;
         }
 
-        if (rt2x00_get_field32(rxd0, RXINFO_W0_MY_BSS))
+        if (rt2x00_get_field32(rxd0, RXD_W0_MY_BSS))
                 rxdesc->dev_flags |= RXDONE_MY_BSS;
 
-        if (rt2x00_get_field32(rxd0, RXINFO_W0_L2PAD))
+        if (rt2x00_get_field32(rxd0, RXD_W0_L2PAD))
                 rxdesc->dev_flags |= RXDONE_L2PAD;
 
         if (rt2x00_get_field32(rxwi1, RXWI_W1_SHORT_GI))