Dear Greg,
On 2/22/2023 2:04 PM, Greg KH wrote:
On Wed, Feb 22, 2023 at 09:39:44AM +0800, Michael Wu wrote:
This patch fixes a problem that USB mouse can't wake up the device that
enters standby.
This not a problem, it is that way by design.
I got it, maybe it's a little problem to say that.
At present, the kernel only checks whether certain USB manufacturers
support wake-up, which will easily cause inconvenience to the
development work of other manufacturers and add unnecessary work to the
maintenance of kernel.
The USB protocol supports judging whether a usb supports the wake-up
function, so it should be more reasonable to add a wake-up source by
directly checking the settings from the USB protocol.
But you do not do that in this patch, why not?
I just want to explain the background of my patch, to prove we could use
a similar way to avoid such a "disturbing" situation.
To reduce the influence, my patch enables remote wakeup for USB mouse
devices refer to what keyboard do.
There was a similar issue on the keyboard before, which was fixed by
this patch (3d61510f4eca), but now the problem happened on the mouse.
This patch uses a similar idea to fix this problem.
Signed-off-by: Michael Wu <michael@xxxxxxxxxxxxxxxxx>
---
drivers/hid/usbhid/hid-core.c | 8 ++++++++
drivers/hid/usbhid/usbmouse.c | 1 +
2 files changed, 9 insertions(+)
diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index be4c731aaa65..d3a6755cca09 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -1189,6 +1189,14 @@ static int usbhid_start(struct hid_device *hid)
device_set_wakeup_enable(&dev->dev, 1);
}
+ /**
+ * NOTE: enable remote wakeup by default for all mouse devices
+ * supporting the boot protocol.
+ */
+ if (interface->desc.bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT &&
+ interface->desc.bInterfaceProtocol == USB_INTERFACE_PROTOCOL_MOUSE)
+ device_set_wakeup_enable(&dev->dev, 1);
Sorry, but we can not take this unless it is proven that this will work
properly for all of these devices. Other operating systems do not do
this last I checked, so there will be problems.
As Mario Limonciello says, they has confirmed that the Microsoft Windows
does set a similar policy as well. Can we talk about more in this topic:
why does Linux not support it?
Of course, if you have other great idea, I will appreciate that if we
can have some further discussion.
thanks,
greg k-h
--
Regards,
Michael Wu
