1b8be5ecff
When IP version >= DEV_VER_V2, gadget:sg_supported is true. So uvc gadget
function driver will use sg to equeue data, first is 8bytes header, the
second is 1016bytes data.
cdns3_prepare_trb: ep2in: trb 0000000000ac755f, dma buf: 0xbf455000, size: 8, burst: 128 ctrl: 0x00000415 (C=1, T=0, ISP, CHAIN, Normal)
cdns3_prepare_trb: ep2in: trb 00000000a574e693, dma buf: 0xc0200fe0, size: 1016, burst: 128 ctrl: 0x00000405 (C=1, T=0, ISP, Normal)
But cdns3_ep_run_transfer() can't correctly handle this case, which only
support one TRB for ISO transfer.
The controller requires duplicate the TD for each SOF if priv_ep->interval
is not 1. DMA will read data from DDR to internal FIFO when get SOF. Send
data to bus when receive IN token. DMA always refill FIFO when get SOF
regardless host send IN token or not. If host send IN token later, some
frames data will be lost.
Fixed it by below major steps:
1. Calculate numembers of TRB base on sg_nums and priv_ep->interval.
2. Remove CHAIN flags for each end TRB of TD when duplicate TD.
3. The controller requires LINK TRB must be first TRB of TD. When check
there are not enough TRBs lefts, just fill LINK TRB for left TRBs.
.... CHAIN_TRB DATA_TRB, CHAIN_TRB DATA_TRB, LINK_TRB ... LINK_TRB
^End of TRB List
Cc: <stable@vger.kernel.org>
Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver")
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20231224153816.1664687-2-Frank.Li@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
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Please read the Documentation/process/changes.rst file, as it contains the
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