Commit c0f1f8e3 authored by Hema HK's avatar Hema HK Committed by Greg Kroah-Hartman
Browse files

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: default avatarHema HK <hemahk@ti.com>
Signed-off-by: default avatarAnand Gadiyar <gadiyar@ti.com>
Signed-off-by: default avatarAjay Kumar Gupta <ajay.gupta@ti.com>
Acked-by: default avatarFelipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent f2263db7
......@@ -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)
......
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