[PATCH v2] Input: hyperv-keyboard: Add the support of hibernation

From: Dexuan Cui
Date: Wed Nov 20 2019 - 02:14:52 EST


During the suspend process and resume process, if there is any keyboard
event, there is a small chance the suspend and the resume process can be
aborted because of hv_kbd_on_receive() -> pm_wakeup_hard_event().

This behavior can be avoided by disabling the Hyper-V keyboard device as
a wakeup source:

echo disabled > /sys/bus/vmbus/drivers/hyperv_keyboard/XXX/power/wakeup
(XXX is the device's GUID).

Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
---

This patch is basically a pure Hyper-V specific change. I suggest it should
go through the Hyper-V tree:
https://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git/log/?h=hyperv-next

Changes in v2:
Removed the "struct notifier_block pm_nb;" after the discussion
with Dmitry Torokhov:
https://lore.kernel.org/lkml/PU1P153MB016914A7C827CA35D7FEB66ABF8B0@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/T/#m8948c711301220a36a1a413eead74cd2fb6dcac1

drivers/input/serio/hyperv-keyboard.c | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)

diff --git a/drivers/input/serio/hyperv-keyboard.c b/drivers/input/serio/hyperv-keyboard.c
index e486a8a74c40..df4e9f6f4529 100644
--- a/drivers/input/serio/hyperv-keyboard.c
+++ b/drivers/input/serio/hyperv-keyboard.c
@@ -259,6 +259,8 @@ static int hv_kbd_connect_to_vsp(struct hv_device *hv_dev)
u32 proto_status;
int error;

+ reinit_completion(&kbd_dev->wait_event);
+
request = &kbd_dev->protocol_req;
memset(request, 0, sizeof(struct synth_kbd_protocol_request));
request->header.type = __cpu_to_le32(SYNTH_KBD_PROTOCOL_REQUEST);
@@ -380,6 +382,29 @@ static int hv_kbd_remove(struct hv_device *hv_dev)
return 0;
}

+static int hv_kbd_suspend(struct hv_device *hv_dev)
+{
+ vmbus_close(hv_dev->channel);
+
+ return 0;
+}
+
+static int hv_kbd_resume(struct hv_device *hv_dev)
+{
+ int ret;
+
+ ret = vmbus_open(hv_dev->channel,
+ KBD_VSC_SEND_RING_BUFFER_SIZE,
+ KBD_VSC_RECV_RING_BUFFER_SIZE,
+ NULL, 0,
+ hv_kbd_on_channel_callback,
+ hv_dev);
+ if (ret == 0)
+ ret = hv_kbd_connect_to_vsp(hv_dev);
+
+ return ret;
+}
+
static const struct hv_vmbus_device_id id_table[] = {
/* Keyboard guid */
{ HV_KBD_GUID, },
@@ -393,6 +418,8 @@ static struct hv_driver hv_kbd_drv = {
.id_table = id_table,
.probe = hv_kbd_probe,
.remove = hv_kbd_remove,
+ .suspend = hv_kbd_suspend,
+ .resume = hv_kbd_resume,
.driver = {
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
--
2.19.1