xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

xhci: Wait until link state trainsits to U0 after setting USB_SS_PORT_LS_U0

Browse Source 
Like U3 case, xHCI spec doesn't specify the upper bound of U0 transition
time. The 20ms is not enough for some devices.

Intead of polling PLS or PLC, we can facilitate the port change event to
know that the link transits to U0 is completed.

While at it, also separate U0 and U3 case to make the code cleaner.

[variable rename to u3exit, and skip completion for usb2 ports -Mathias ]
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200312144517.1593-8-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Kai-Heng Feng
2020-03-12 16:45:15 +02:00
committed by Greg Kroah-Hartman
parent eb002726fa
commit 0200b9f790
4 changed files with 34 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
drivers/usb/host/xhci-mem.c
View File

@@ -2552,6 +2552,7 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
xhci->usb3_rhub.bus_state.resume_done[i] = 0;
/* Only the USB 2.0 completions will ever be used. */
init_completion(&xhci->usb2_rhub.bus_state.rexit_done[i]);
init_completion(&xhci->usb3_rhub.bus_state.u3exit_done[i]);
}
if (scratchpad_alloc(xhci, flags))