• Sebastian Andrzej Siewior's avatar
    usb: musb: start musb on the udc side, too · 001dd84a
    Sebastian Andrzej Siewior authored
    I have am335x-evm with one port running in OTG mode. Since commit
    fe4cb091 ("usb: musb: gadget: remove hcd initialization") the loaded
    gadget does non pop up on the host. All I see is
    |usb 4-5: new high-speed USB device number 52 using ehci-pci
    |usb 4-5: device descriptor read/64, error -110
    
    Since a later commit 2cc65fea ("usb: musb: add musb_host_setup() and
    musb_host_cleanup()) the gadget shows up on the host again but only
    in OTG mode (because we have the host init code running). It does not
    work in device only mode.
    If running in OTG mode and the gadget is removed and added back (rmmod
    followed by modprobe of a gadget) then the same error is pops up on the
    host side.
    
    This patch ensures that the gadget side also executes musb_start() which
    puts the chip in "connect accept" mode. With this change the device
    works in OTG & device mode and the gadget can be added & removed
    multiple times.
    A device (if musb is in OTG mode acting as a host) is only recognized if
    it is attached during module load (musb_hdrc module). After the device
    unplugged and plugged again the host does not recognize it. We get a
    buch of errors if musb running in OTG mode, attached to a host and no
    gadget is loaded. Bah.
    This is one step forward. Host & device only mode should work. I will
    look at OTG later. I looked at this before commit fe4cb091 and OTG wasn't
    working there perfectly so I am not sure that it is a regression :)
    
    Cc: <stable@vger.kernel.org> # v3.11
    Cc: Daniel Mack <zonque@gmail.com>
    Cc: Peter Korsgaard <jacmet@sunsite.dk>
    Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
    Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
    001dd84a
musb_virthub.c 11.3 KB