shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-09 12:17:12 +09:00
Code Issues Packages Projects Releases Wiki Activity

USB: workaround for specified USB3 PHY disconnection det issue

Browse Source 
Some special SoCs (e.g. rk322xh) USB3 PHY have problem to detect
disconnection, they lose the ability to detect an absence of Rx
termination specified in USB3 spec Table 6-21, fortunately, the
USB3 PHY can detect port link state change when USB3 device is
unplugged, so we can do soft disconnect according to the PLC.

Change-Id: I2cbd62fddc8a1f9c5a264d705db43fb0cf3e035c
Signed-off-by: William Wu <wulf@rock-chips.com>
Signed-off-by: Frank Wang <frank.wang@rock-chips.com>
This commit is contained in:
William Wu
2017-09-27 10:32:21 +08:00
committed by Tao Huang
parent 01b0c61bc9
commit fb771ab91a
1 changed files with 18 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

19
drivers/usb/core/hub.c
View File

@@ -5028,7 +5028,24 @@ static void port_event(struct usb_hub *hub, int port1)
} else {
usb_unlock_port(port_dev);
usb_lock_device(udev);
usb_reset_device(udev);
/**
* Some special SoCs (e.g. rk322xh) USB3 PHY lose the
* ability to detect a disconnection when USB3 device
* plug out, fortunately, it can detect port link state
* change here, so we can do soft disconnect according
* to the PLC here.
*
* And we only need to do the soft disconnect for root
* hub. In addition, we just reuse the autosuspend quirk
* but not add a new quirk for this issue. Because this
* issue always occurs with autosuspend problem.
*/
if (!hub->hdev->parent && (hdev->quirks &
USB_QUIRK_AUTO_SUSPEND))
usb_remove_device(udev);
else
usb_reset_device(udev);
usb_unlock_device(udev);
usb_lock_port(port_dev);
connect_change = 0;