linux_dsm_epyc7002/drivers/usb/core
Mathias Nyman d590c23111 usb: Avoid unnecessary LPM enabling and disabling during suspend and resume
The original motivation for disabling/enabling Link PM at device
suspend/resume was to force link state to go via U0 before suspend sets
the link state to U3. Going directly from U2 to U3 is not allowed.

Disabling LPM will forced the link state to U0, but will send a lot of
Set port feature requests for evert suspend and resume.

This is not needed as Hub hardware will take care of going via U0
when a U2 -> U3 transition is requested [1]

[1] USB 3.1 specification section 10.16.2.10 Set Port Feature:

"If the value is 3, then host software wants to selectively suspend the
device connected to this port. The hub shall transition the link to U3
from any of the other U states using allowed link state transitions.
If the port is not already in the U0 state, then it shall transition the
port to the U0 state and then initiate the transition to U3.
While this state is active, the hub does not propagate downstream-directed
traffic to this port, but the hub will respond to resume signaling from the
port"

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
..
buffer.c usb: separate out sysdev pointer from usb_bus 2017-03-23 08:20:21 +01:00
config.c usb-core: Add LINEAR_FRAME_INTR_BINTERVAL USB quirk 2017-03-14 17:07:31 +08:00
devices.c usb: fix some references for /proc/bus/usb 2017-04-18 16:54:19 +02:00
devio.c USB: add usbfs ioctl to retrieve the connection speed 2017-06-13 10:48:24 +02:00
driver.c usb: hub: Do not attempt to autosuspend disconnected devices 2017-03-23 08:13:22 +01:00
endpoint.c usb: patches for v4.10 merge window 2016-11-18 16:02:15 +01:00
file.c USB: Proper handling of Race Condition when two USB class drivers try to call init_usb_class simultaneously 2017-03-29 11:55:25 +02:00
generic.c USB: core: add missing license information to some files 2016-10-29 12:51:56 -04:00
hcd-pci.c usb: hcd: out of bounds access in for_each_companion 2016-04-13 12:06:18 -07:00
hcd.c USB: of: fix root-hub device-tree node handling 2017-06-13 11:07:32 +02:00
hub.c usb: Avoid unnecessary LPM enabling and disabling during suspend and resume 2017-06-15 22:17:46 +02:00
hub.h usb: Support USB 3.1 extended port status request 2016-01-24 20:16:52 -08:00
Kconfig docs-rst: fix usb cross-references 2017-04-11 14:41:29 -06:00
ledtrig-usbport.c usb: core: usbport: Use proper LED API to fix potential crash 2016-12-06 08:37:41 +01:00
Makefile usb: add CONFIG_USB_PCI for system have both PCI HW and non-PCI based USB HW 2017-03-17 13:16:56 +09:00
message.c usb: get rid of some ReST doc build errors 2017-04-11 14:40:48 -06:00
notify.c USB: core: add missing license information to some files 2016-10-29 12:51:56 -04:00
of.c USB: of: document reference taken by child-lookup helper 2017-06-13 11:07:32 +02:00
otg_whitelist.h usb: core: use IS_ENABLED() instead of checking for built-in or module 2016-09-02 14:36:33 +02:00
port.c Revert "USB / PM: Allow USB devices to remain runtime-suspended when sleeping" 2016-05-02 08:44:31 -07:00
quirks.c usb-core: Add LINEAR_FRAME_INTR_BINTERVAL USB quirk 2017-03-14 17:07:31 +08:00
sysfs.c USB: core: add missing license information to some files 2016-10-29 12:51:56 -04:00
urb.c USB: core: replace %p with %pK 2017-05-17 11:27:41 +02:00
usb-acpi.c usb: optimize acpi companion search for usb port devices 2017-06-03 18:02:58 +09:00
usb.c USB: of: fix root-hub device-tree node handling 2017-06-13 11:07:32 +02:00
usb.h USB: core: add missing license information to some files 2016-10-29 12:51:56 -04:00