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3f91484f6c
Commit65111084c6("USB: more omap_udc updates (dma and omap1710)") added setting for DMA burst 4 mode. But I think this should be undone for two reasons: - It breaks DMA on 15xx boards - transfers just silently stall. - On newer OMAP1 boards, like Nokia 770 (omap1710), there is no measurable performance impact when testing TCP throughput with g_ether with large 15000 byte MTU size. It's also worth noting that when the original change was made, the OMAP_DMA_DATA_BURST_4 handling in arch/arm/plat-omap/dma.c was broken, and actually resulted in the same as the OMAP_DMA_DATA_BURST_DIS i.e. burst disabled. This was fixed not until a couple kernel releases later in an unrelated commit1a8bfa1eb9("[ARM] 3142/1: OMAP 2/5: Update files common to omap1 and omap2"). So based on this it seems there was never really a very good reason to enable this burst mode in omap_udc, so remove it now to allow 15xx DMA to work again (it provides 2x throughput compared to PIO mode). Fixes:65111084c6("[PATCH] USB: more omap_udc updates (dma and omap1710)") Cc: stable <stable@kernel.org> Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Link: https://patch.msgid.link/ad06qHLclWHeSGnV@darkstar.musicnaut.iki.fi Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>