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authorLinus Torvalds <torvalds@linux-foundation.org>2014-06-03 20:11:20 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2014-06-03 20:11:20 +0400
commite5c4ecdc55b6d824365ba7964bcd3185223f9688 (patch)
tree405556c9fe703094dd0fc07bc89d9a2fdb5ee525 /Documentation/usb/chipidea.txt
parent49eb7b0750d9483c74e9c14ae6ea1e9d62481c3c (diff)
parent4a95b1fce97756d0333f8232eb7ed6974e93b054 (diff)
downloadlinux-e5c4ecdc55b6d824365ba7964bcd3185223f9688.tar.xz
Merge tag 'usb-3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb into next
Pull USB driver updates from Greg KH: "Here is the big USB driver pull request for 3.16-rc1. Nothing huge here, but lots of little things in the USB core, and in lots of drivers. Hopefully the USB power management will be work better now that it has been reworked to do per-port power control dynamically. There's also a raft of gadget driver updates and fixes, CONFIG_USB_DEBUG is finally gone now that everything has been converted over to the dynamic debug inteface, the last hold-out drivers were cleaned up and the config option removed. There were also other minor things all through the drivers/usb/ tree, the shortlog shows this pretty well. All have been in linux-next, including the very last patch, which came from linux-next to fix a build issue on some platforms" * tag 'usb-3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (314 commits) usb: hub_handle_remote_wakeup() only exists for CONFIG_PM=y USB: orinoco_usb: remove CONFIG_USB_DEBUG support USB: media: lirc: igorplugusb: remove CONFIG_USB_DEBUG support USB: media: streamzap: remove CONFIG_USB_DEBUG USB: media: redrat3: remove CONFIG_USB_DEBUG usage USB: media: redrat3: remove unneeded tracing macro usb: qcserial: add additional Sierra Wireless QMI devices usb: host: max3421-hcd: Use module_spi_driver usb: host: max3421-hcd: Allow platform-data to specify Vbus polarity usb: host: max3421-hcd: fix "spi_rd8" uses dynamic stack allocation warning usb: host: max3421-hcd: Fix missing unlock in max3421_urb_enqueue() usb: qcserial: add Netgear AirCard 341U Documentation: dt-bindings: update xhci-platform DT binding for R-Car H2 and M2 usb: host: xhci-plat: add xhci_plat_start() usb: host: max3421-hcd: Fix potential NULL urb dereference Revert "usb: gadget: net2280: Add support for PLX USB338X" USB: usbip: remove CONFIG_USB_DEBUG reference USB: remove CONFIG_USB_DEBUG from defconfig files usb: resume child device when port is powered on usb: hub_handle_remote_wakeup() depends on CONFIG_PM_RUNTIME=y ...
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+1. How to test OTG FSM(HNP and SRP)
+-----------------------------------
+To show how to demo OTG HNP and SRP functions via sys input files
+with 2 Freescale i.MX6Q sabre SD boards.
+
+1.1 How to enable OTG FSM in menuconfig
+---------------------------------------
+Select CONFIG_USB_OTG_FSM, rebuild kernel Image and modules.
+If you want to check some internal variables for otg fsm,
+select CONFIG_USB_CHIPIDEA_DEBUG, there are 2 files which
+can show otg fsm variables and some controller registers value:
+cat /sys/kernel/debug/ci_hdrc.0/otg
+cat /sys/kernel/debug/ci_hdrc.0/registers
+
+1.2 Test operations
+-------------------
+1) Power up 2 Freescale i.MX6Q sabre SD boards with gadget class driver loaded
+ (e.g. g_mass_storage).
+
+2) Connect 2 boards with usb cable with one end is micro A plug, the other end
+ is micro B plug.
+
+ The A-device(with micro A plug inserted) should enumrate B-device.
+
+3) Role switch
+ On B-device:
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+ if HNP polling is not supported, also need:
+ On A-device:
+ echo 0 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_req
+
+ B-device should take host role and enumrate A-device.
+
+4) A-device switch back to host.
+ On B-device:
+ echo 0 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+ A-device should switch back to host and enumrate B-device.
+
+5) Remove B-device(unplug micro B plug) and insert again in 10 seconds,
+ A-device should enumrate B-device again.
+
+6) Remove B-device(unplug micro B plug) and insert again after 10 seconds,
+ A-device should NOT enumrate B-device.
+
+ if A-device wants to use bus:
+ On A-device:
+ echo 0 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_drop
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_req
+
+ if B-device wants to use bus:
+ On B-device:
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+7) A-device power down the bus.
+ On A-device:
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_drop
+
+ A-device should disconnect with B-device and power down the bus.
+
+8) B-device does data pulse for SRP.
+ On B-device:
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+ A-device should resume usb bus and enumrate B-device.
+
+1.3 Reference document
+----------------------
+"On-The-Go and Embedded Host Supplement to the USB Revision 2.0 Specification
+July 27, 2012 Revision 2.0 version 1.1a"