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>

2 files changed, 97 insertions, 31 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))
diff --git a/drivers/net/wireless/rt2x00/rt2800usb.h b/drivers/net/wireless/rt2x00/rt2800usb.h
index 1e4340a182ef..d1d8ae94b4d4 100644
--- a/drivers/net/wireless/rt2x00/rt2800usb.h
+++ b/drivers/net/wireless/rt2x00/rt2800usb.h
@@ -79,6 +79,8 @@
  */
 #define TXINFO_DESC_SIZE                ( 1 * sizeof(__le32) )
 #define RXINFO_DESC_SIZE                ( 1 * sizeof(__le32) )
+#define RXWI_DESC_SIZE                  ( 4 * sizeof(__le32) )
+#define RXD_DESC_SIZE                   ( 1 * sizeof(__le32) )
 
 /*
  * TX Info structure
@@ -101,6 +103,54 @@
 #define TXINFO_W0_USB_DMA_TX_BURST      FIELD32(0x80000000)
 
 /*
+ * RX Info structure
+ */
+
+/*
+ * Word 0
+ */
+
+#define RXINFO_W0_USB_DMA_RX_PKT_LEN    FIELD32(0x0000ffff)
+
+/*
+ * RX WI structure
+ */
+
+/*
+ * Word0
+ */
+#define RXWI_W0_WIRELESS_CLI_ID         FIELD32(0x000000ff)
+#define RXWI_W0_KEY_INDEX               FIELD32(0x00000300)
+#define RXWI_W0_BSSID                   FIELD32(0x00001c00)
+#define RXWI_W0_UDF                     FIELD32(0x0000e000)
+#define RXWI_W0_MPDU_TOTAL_BYTE_COUNT   FIELD32(0x0fff0000)
+#define RXWI_W0_TID                     FIELD32(0xf0000000)
+
+/*
+ * Word1
+ */
+#define RXWI_W1_FRAG                    FIELD32(0x0000000f)
+#define RXWI_W1_SEQUENCE                FIELD32(0x0000fff0)
+#define RXWI_W1_MCS                     FIELD32(0x007f0000)
+#define RXWI_W1_BW                      FIELD32(0x00800000)
+#define RXWI_W1_SHORT_GI                FIELD32(0x01000000)
+#define RXWI_W1_STBC                    FIELD32(0x06000000)
+#define RXWI_W1_PHYMODE                 FIELD32(0xc0000000)
+
+/*
+ * Word2
+ */
+#define RXWI_W2_RSSI0                   FIELD32(0x000000ff)
+#define RXWI_W2_RSSI1                   FIELD32(0x0000ff00)
+#define RXWI_W2_RSSI2                   FIELD32(0x00ff0000)
+
+/*
+ * Word3
+ */
+#define RXWI_W3_SNR0                    FIELD32(0x000000ff)
+#define RXWI_W3_SNR1                    FIELD32(0x0000ff00)
+
+/*
  * RX descriptor format for RX Ring.
  */
 
@@ -115,25 +165,25 @@
  * AMSDU: rx with 802.3 header, not 802.11 header.
  */
 
-#define RXINFO_W0_BA                    FIELD32(0x00000001)
-#define RXINFO_W0_DATA                  FIELD32(0x00000002)
-#define RXINFO_W0_NULLDATA              FIELD32(0x00000004)
-#define RXINFO_W0_FRAG                  FIELD32(0x00000008)
-#define RXINFO_W0_UNICAST_TO_ME         FIELD32(0x00000010)
-#define RXINFO_W0_MULTICAST             FIELD32(0x00000020)
-#define RXINFO_W0_BROADCAST             FIELD32(0x00000040)
-#define RXINFO_W0_MY_BSS                FIELD32(0x00000080)
-#define RXINFO_W0_CRC_ERROR             FIELD32(0x00000100)
-#define RXINFO_W0_CIPHER_ERROR          FIELD32(0x00000600)
-#define RXINFO_W0_AMSDU                 FIELD32(0x00000800)
-#define RXINFO_W0_HTC                   FIELD32(0x00001000)
-#define RXINFO_W0_RSSI                  FIELD32(0x00002000)
-#define RXINFO_W0_L2PAD                 FIELD32(0x00004000)
-#define RXINFO_W0_AMPDU                 FIELD32(0x00008000)
-#define RXINFO_W0_DECRYPTED             FIELD32(0x00010000)
-#define RXINFO_W0_PLCP_RSSI             FIELD32(0x00020000)
-#define RXINFO_W0_CIPHER_ALG            FIELD32(0x00040000)
-#define RXINFO_W0_LAST_AMSDU            FIELD32(0x00080000)
-#define RXINFO_W0_PLCP_SIGNAL           FIELD32(0xfff00000)
+#define RXD_W0_BA                       FIELD32(0x00000001)
+#define RXD_W0_DATA                     FIELD32(0x00000002)
+#define RXD_W0_NULLDATA                 FIELD32(0x00000004)
+#define RXD_W0_FRAG                     FIELD32(0x00000008)
+#define RXD_W0_UNICAST_TO_ME            FIELD32(0x00000010)
+#define RXD_W0_MULTICAST                FIELD32(0x00000020)
+#define RXD_W0_BROADCAST                FIELD32(0x00000040)
+#define RXD_W0_MY_BSS                   FIELD32(0x00000080)
+#define RXD_W0_CRC_ERROR                FIELD32(0x00000100)
+#define RXD_W0_CIPHER_ERROR             FIELD32(0x00000600)
+#define RXD_W0_AMSDU                    FIELD32(0x00000800)
+#define RXD_W0_HTC                      FIELD32(0x00001000)
+#define RXD_W0_RSSI                     FIELD32(0x00002000)
+#define RXD_W0_L2PAD                    FIELD32(0x00004000)
+#define RXD_W0_AMPDU                    FIELD32(0x00008000)
+#define RXD_W0_DECRYPTED                FIELD32(0x00010000)
+#define RXD_W0_PLCP_RSSI                FIELD32(0x00020000)
+#define RXD_W0_CIPHER_ALG               FIELD32(0x00040000)
+#define RXD_W0_LAST_AMSDU               FIELD32(0x00080000)
+#define RXD_W0_PLCP_SIGNAL              FIELD32(0xfff00000)
 
 #endif /* RT2800USB_H */