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rt2x00: Align ieee80211 header to 4-byte boundary for PCI devices

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Some hardware require the ieee80211 header to be aligned to a
4-byte boundary before mapping it to the DMA. Otherwise some
frames (like beacons) will not be send out correctly by the
device.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Ivo van Doorn 2009-08-08 23:53:47 +02:00 committed by John W. Linville
parent 267e898755
commit 93354cbbcb
1 changed files with 12 additions and 0 deletions
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12
drivers/net/wireless/rt2x00/rt2x00queue.c
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@ -453,9 +453,21 @@ int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb)
rt2x00crypto_tx_remove_iv(skb, &txdesc);
}
/*
* When DMA allocation is required we should guarentee to the
* driver that the DMA is aligned to a 4-byte boundary.
* Aligning the header to this boundary can be done by calling
* rt2x00queue_payload_align with the header length of 0.
* However some drivers require L2 padding to pad the payload
* rather then the header. This could be a requirement for
* PCI and USB devices, while header alignment only is valid
* for PCI devices.
*/
if (test_bit(DRIVER_REQUIRE_L2PAD, &queue->rt2x00dev->flags))
rt2x00queue_payload_align(entry->skb, true,
txdesc.header_length);
else if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
rt2x00queue_payload_align(entry->skb, false, 0);
/*
* It could be possible that the queue was corrupted and this