Li Jun | 9159e04 | 2014-04-23 15:56:54 +0800 | [diff] [blame] | 1 | 1. How to test OTG FSM(HNP and SRP) |
| 2 | ----------------------------------- |
| 3 | To show how to demo OTG HNP and SRP functions via sys input files |
| 4 | with 2 Freescale i.MX6Q sabre SD boards. |
| 5 | |
| 6 | 1.1 How to enable OTG FSM in menuconfig |
| 7 | --------------------------------------- |
Peter Chen | ec447ab | 2014-05-04 09:24:43 +0800 | [diff] [blame] | 8 | Select CONFIG_USB_OTG_FSM, rebuild kernel Image and modules. |
Li Jun | 9159e04 | 2014-04-23 15:56:54 +0800 | [diff] [blame] | 9 | If you want to check some internal variables for otg fsm, |
| 10 | select CONFIG_USB_CHIPIDEA_DEBUG, there are 2 files which |
| 11 | can show otg fsm variables and some controller registers value: |
| 12 | cat /sys/kernel/debug/ci_hdrc.0/otg |
| 13 | cat /sys/kernel/debug/ci_hdrc.0/registers |
| 14 | |
| 15 | 1.2 Test operations |
| 16 | ------------------- |
| 17 | 1) Power up 2 Freescale i.MX6Q sabre SD boards with gadget class driver loaded |
| 18 | (e.g. g_mass_storage). |
| 19 | |
| 20 | 2) Connect 2 boards with usb cable with one end is micro A plug, the other end |
| 21 | is micro B plug. |
| 22 | |
| 23 | The A-device(with micro A plug inserted) should enumrate B-device. |
| 24 | |
| 25 | 3) Role switch |
| 26 | On B-device: |
| 27 | echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req |
| 28 | |
| 29 | if HNP polling is not supported, also need: |
| 30 | On A-device: |
| 31 | echo 0 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_req |
| 32 | |
| 33 | B-device should take host role and enumrate A-device. |
| 34 | |
| 35 | 4) A-device switch back to host. |
| 36 | On B-device: |
| 37 | echo 0 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req |
| 38 | |
| 39 | A-device should switch back to host and enumrate B-device. |
| 40 | |
| 41 | 5) Remove B-device(unplug micro B plug) and insert again in 10 seconds, |
| 42 | A-device should enumrate B-device again. |
| 43 | |
| 44 | 6) Remove B-device(unplug micro B plug) and insert again after 10 seconds, |
| 45 | A-device should NOT enumrate B-device. |
| 46 | |
| 47 | if A-device wants to use bus: |
| 48 | On A-device: |
| 49 | echo 0 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_drop |
| 50 | echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_req |
| 51 | |
| 52 | if B-device wants to use bus: |
| 53 | On B-device: |
| 54 | echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req |
| 55 | |
| 56 | 7) A-device power down the bus. |
| 57 | On A-device: |
| 58 | echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_drop |
| 59 | |
| 60 | A-device should disconnect with B-device and power down the bus. |
| 61 | |
| 62 | 8) B-device does data pulse for SRP. |
| 63 | On B-device: |
| 64 | echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req |
| 65 | |
| 66 | A-device should resume usb bus and enumrate B-device. |
| 67 | |
| 68 | 1.3 Reference document |
| 69 | ---------------------- |
| 70 | "On-The-Go and Embedded Host Supplement to the USB Revision 2.0 Specification |
| 71 | July 27, 2012 Revision 2.0 version 1.1a" |