• Sebastian Andrzej Siewior's avatar
    usb: musb dma: add cppi41 dma driver · 9b3452d1
    Sebastian Andrzej Siewior authored
    This driver is currently used by musb' cppi41 couter part. I may merge
    both dma engine user of musb at some point but not just yet.
    
    The driver seems to work in RX/TX mode in host mode, tested on mass
    storage. I increaed the size of the TX / RX transfers and waited for the
    core code to cancel a transfers and it seems to recover.
    
    v2..3:
    - use mall transfers on RX side and check data toggle.
    - use rndis mode on tx side so we haveon interrupt for 4096 transfers.
    - remove custom "transferred" hack and use dmaengine_tx_status() to
      compute the total amount of data that has been transferred.
    - cancel transfers and reclaim descriptors
    
    v1..v2:
    - RX path added
    - dma mode 0 & 1 is working
    - device tree nodes re-created.
    
    Cc: Vinod Koul <vinod.koul@intel.com>
    Cc: Dan Williams <djbw@fb.com>
    Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
    Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
    9b3452d1
am335x-evm.dts 12 KB