-
Radhey Shyam Pandey authored
In overlay application we noticed that dma channel node probe order is inverted i.e s2mm channel is probed first followed by mm2s channel. The reason for this inversion is fdtoverlay utility which uses a function called fdt_add_subnode(*). It stores the subnodes after the properties, this has the effect of inserting the new subnode before any others and the end result is a reversal. Because of this inverted channel probe order, the node probed first is assigned a '0' index instead of Channel ID should be '0' for tx and '1' for rx and dmatest client using the DT convention fails in dma transfer as channel are swapped. To fix above behavior and make channel assignment index independent of probe order, always assign mm2s channel at '0' index and the s2mm channel at IP specific fixed offset derived from the max_channels count. Signed-off-by:
Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com> Link: https://lore.kernel.org/r/1580388865-9960-3-git-send-email-radhey.shyam.pandey@xilinx.comSigned-off-by:
Vinod Koul <vkoul@kernel.org>
14ccf0aa