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USB: musb: Enable the maximum supported burst mode for DMA 

Setting MUSB Burst Mode 3 automatically enables support for
lower burst modes (BURST4, BURST8, BURST16 or bursts of unspecified
length). There is no need to set these burst modes based on the
packet size. Also enable the burst mode for both mode1 and mode0.

This is a fix for buggy hardware - having the lower burst modes
enabled can potentially cause lockups of the DMA engine used in
OMAP2/3/4 chips.

Signed-off-by: Hema HK <hemahk@ti.com>
Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Ajay Kumar Gupta <ajay.gupta@ti.com>
Acked-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Hema HK 2010-06-24 23:07:09 +05:30 committed by Greg Kroah-Hartman
parent f2263db74a
commit c0f1f8e38f
1 changed files with 2 additions and 11 deletions
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13
drivers/usb/musb/musbhsdma.c
View File

@ -132,18 +132,9 @@ static void configure_channel(struct dma_channel *channel,
if (mode) {
csr |= 1 << MUSB_HSDMA_MODE1_SHIFT;
BUG_ON(len < packet_sz);
if (packet_sz >= 64) {
csr |= MUSB_HSDMA_BURSTMODE_INCR16
<< MUSB_HSDMA_BURSTMODE_SHIFT;
} else if (packet_sz >= 32) {
csr |= MUSB_HSDMA_BURSTMODE_INCR8
<< MUSB_HSDMA_BURSTMODE_SHIFT;
} else if (packet_sz >= 16) {
csr |= MUSB_HSDMA_BURSTMODE_INCR4
<< MUSB_HSDMA_BURSTMODE_SHIFT;
}
}
csr |= MUSB_HSDMA_BURSTMODE_INCR16
<< MUSB_HSDMA_BURSTMODE_SHIFT;
csr |= (musb_channel->epnum << MUSB_HSDMA_ENDPOINT_SHIFT)
| (1 << MUSB_HSDMA_ENABLE_SHIFT)