This patch adds response to a_alt_hnp_support set feature request from legacy
A device, that is, B-device can provide a message to the user indicating that
the user needs to connect the B-device to an alternate port on the A-device.
A device sets this feature indicates to the B-device that it is connected
to an A-device port that is not capable of HNP, but that the A-device does have
an alternate port that is capable of HNP.
[Peter]
Without this patch, the OTG B device can't be enumerated on
non-HNP port at A device, see below log:
[ 2.287464] usb 1-1: Dual-Role OTG device on non-HNP port
[ 2.293105] usb 1-1: can't set HNP mode: -32
[ 2.417422] usb 1-1: new high-speed USB device number 4 using ci_hdrc
[ 2.460635] usb 1-1: Dual-Role OTG device on non-HNP port
[ 2.466424] usb 1-1: can't set HNP mode: -32
[ 2.587464] usb 1-1: new high-speed USB device number 5 using ci_hdrc
[ 2.630649] usb 1-1: Dual-Role OTG device on non-HNP port
[ 2.636436] usb 1-1: can't set HNP mode: -32
[ 2.641003] usb usb1-port1: unable to enumerate USB device
Cc: stable <stable@vger.kernel.org>
Acked-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Li Jun <b47624@freescale.com>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
d20f780799