[PATCH 2/3] usb: musb: musb_cppi41: Make CPPI aware of high bandwidth transfers

From: George Cherian
Date: Fri Jan 24 2014 - 09:15:59 EST


Enable CPPI to handle high bandwidth transfers, especially to support
webcam captures. Use a single bd to get the whole of the data in case of
high bandwidth transfers.

Signed-off-by: George Cherian <george.cherian@xxxxxx>
---
drivers/usb/musb/musb_cppi41.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/drivers/usb/musb/musb_cppi41.c b/drivers/usb/musb/musb_cppi41.c
index f889296..39ee516 100644
--- a/drivers/usb/musb/musb_cppi41.c
+++ b/drivers/usb/musb/musb_cppi41.c
@@ -448,12 +448,25 @@ static int cppi41_dma_channel_program(struct dma_channel *channel,
dma_addr_t dma_addr, u32 len)
{
int ret;
+ struct cppi41_dma_channel *cppi41_channel = channel->private_data;
+ int hb_mult = 0;

BUG_ON(channel->status == MUSB_DMA_STATUS_UNKNOWN ||
channel->status == MUSB_DMA_STATUS_BUSY);

+ if (is_host_active(cppi41_channel->controller->musb)) {
+ if (cppi41_channel->is_tx)
+ hb_mult = cppi41_channel->hw_ep->out_qh->hb_mult;
+ else
+ hb_mult = cppi41_channel->hw_ep->in_qh->hb_mult;
+ }
+
channel->status = MUSB_DMA_STATUS_BUSY;
channel->actual_len = 0;
+
+ if (hb_mult)
+ packet_sz = hb_mult * (packet_sz & 0x7FF);
+
ret = cppi41_configure_channel(channel, packet_sz, mode, dma_addr, len);
if (!ret)
channel->status = MUSB_DMA_STATUS_FREE;
--
1.8.1

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