diff options
| author | RA-Jay Hung <Jay_Hung@ralinktech.com> | 2010-11-13 19:11:46 +0100 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2010-11-17 16:18:55 -0500 |
| commit | b43d63bd69ae5464a52bf1796e84097607917b2f (patch) | |
| tree | 250c4ae0481e888392dca3f24c188b6eed341a31 /drivers/net/wireless/rt2x00/rt2800usb.c | |
| parent | ef8397cfb3a385bc57a32213d0e4a5b7903a9dc6 (diff) | |
rt2x00: Fix rt2800 USB TX Path DMA issue
rt2800usb chips need to add 1~3 bytes zero padding after each 802.11 header & payload,
and at the end need to add 4 bytes zero padding whether doing TX bulk aggregation or not,
TXINFO_W0_USB_DMA_TX_PKT_LEN in TXINFO must include 1-3 bytes padding after 802.11 header & payload
but do not include 4 bytes end zero padding.
In rt2800usb_get_tx_data_len do not consider multiple of the USB packet size case, sometimes this will
cause USB DMA problem.
Signed-off-by: RA-Jay Hung <jay_hung@ralinktech.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'drivers/net/wireless/rt2x00/rt2800usb.c')
| -rw-r--r-- | drivers/net/wireless/rt2x00/rt2800usb.c | 39 |
1 files changed, 26 insertions, 13 deletions
diff --git a/drivers/net/wireless/rt2x00/rt2800usb.c b/drivers/net/wireless/rt2x00/rt2800usb.c index 2933bf1d74bb..935b76d3ce4f 100644 --- a/drivers/net/wireless/rt2x00/rt2800usb.c +++ b/drivers/net/wireless/rt2x00/rt2800usb.c @@ -307,8 +307,14 @@ static void rt2800usb_write_tx_desc(struct queue_entry *entry, * Initialize TXINFO descriptor */ rt2x00_desc_read(txi, 0, &word); + + /* + * The size of TXINFO_W0_USB_DMA_TX_PKT_LEN is + * TXWI + 802.11 header + L2 pad + payload + pad, + * so need to decrease size of TXINFO and USB end pad. + */ rt2x00_set_field32(&word, TXINFO_W0_USB_DMA_TX_PKT_LEN, - entry->skb->len - TXINFO_DESC_SIZE); + entry->skb->len - TXINFO_DESC_SIZE - 4); rt2x00_set_field32(&word, TXINFO_W0_WIV, !test_bit(ENTRY_TXD_ENCRYPT_IV, &txdesc->flags)); rt2x00_set_field32(&word, TXINFO_W0_QSEL, 2); @@ -326,22 +332,29 @@ static void rt2800usb_write_tx_desc(struct queue_entry *entry, skbdesc->desc_len = TXINFO_DESC_SIZE + TXWI_DESC_SIZE; } -/* - * TX data initialization - */ -static int rt2800usb_get_tx_data_len(struct queue_entry *entry) +static void rt2800usb_write_tx_data(struct queue_entry *entry, + struct txentry_desc *txdesc) { - int length; + u8 padding_len; /* - * The length _must_ include 4 bytes padding, - * it should always be multiple of 4, - * but it must _not_ be a multiple of the USB packet size. + * pad(1~3 bytes) is added after each 802.11 payload. + * USB end pad(4 bytes) is added at each USB bulk out packet end. + * TX frame format is : + * | TXINFO | TXWI | 802.11 header | L2 pad | payload | pad | USB end pad | + * |<------------- tx_pkt_len ------------->| */ - length = roundup(entry->skb->len + 4, 4); - length += (4 * !(length % entry->queue->usb_maxpacket)); + rt2800_write_tx_data(entry, txdesc); + padding_len = roundup(entry->skb->len + 4, 4) - entry->skb->len; + memset(skb_put(entry->skb, padding_len), 0, padding_len); +} - return length; +/* + * TX data initialization + */ +static int rt2800usb_get_tx_data_len(struct queue_entry *entry) +{ + return entry->skb->len; } /* @@ -579,7 +592,7 @@ static const struct rt2x00lib_ops rt2800usb_rt2x00_ops = { .link_tuner = rt2800_link_tuner, .watchdog = rt2800usb_watchdog, .write_tx_desc = rt2800usb_write_tx_desc, - .write_tx_data = rt2800_write_tx_data, + .write_tx_data = rt2800usb_write_tx_data, .write_beacon = rt2800_write_beacon, .get_tx_data_len = rt2800usb_get_tx_data_len, .kick_tx_queue = rt2x00usb_kick_tx_queue, |