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authorLi Jun <jun.li@nxp.com>2016-02-19 05:04:47 +0300
committerFelipe Balbi <balbi@kernel.org>2016-03-04 16:14:37 +0300
commitdfbae3309568f296e5dccfe1ec10db0f6804b756 (patch)
tree313cc86f04723b547d3bb456e2f194041b55f6e0 /Documentation/usb
parent75d2f754e2d8937890336803ae27e3503f192705 (diff)
downloadlinux-dfbae3309568f296e5dccfe1ec10db0f6804b756.tar.xz
Documentation: usb: chipidea: Update test procedure for HNP polling
Update HNP test procedure as HNP polling is supported. Acked-by: Peter Chen <peter.chen@nxp.com> Signed-off-by: Li Jun <jun.li@nxp.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
Diffstat (limited to 'Documentation/usb')
-rw-r--r--Documentation/usb/chipidea.txt9
1 files changed, 5 insertions, 4 deletions
diff --git a/Documentation/usb/chipidea.txt b/Documentation/usb/chipidea.txt
index 05f735a1b5a5..678741b0f213 100644
--- a/Documentation/usb/chipidea.txt
+++ b/Documentation/usb/chipidea.txt
@@ -26,16 +26,17 @@ cat /sys/kernel/debug/ci_hdrc.0/registers
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
+ or, by introducing HNP polling, B-Host can know when A-peripheral wish
+ to be host role, so this role switch also can be trigged in A-peripheral
+ side by answering the polling from B-Host, this can be done on A-device:
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_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,