[PATCH 1/1][SRU][Noble] UBUNTU: SAUCE: platform/x86/hp: Avoid spurious wakeup on HP ProOne 440

[Chris Chiu]

From: Kai-Heng Feng <kai.heng.feng at canonical.com>

BugLink: https://bugs.launchpad.net/bugs/2085065

The HP ProOne 440 has a power saving design that when the display is
off, it also cuts the USB touchscreen device's power off.

This can cause system early wakeup because cutting the power off the
touchscreen device creates a disconnect event and prevent the system
from suspending:
[  445.814574] hub 2-0:1.0: hub_suspend
[  445.814652] usb usb2: bus suspend, wakeup 0
[  445.824629] xhci_hcd 0000:00:14.0: Port change event, 1-11, id 11, portsc: 0x202a0
[  445.824639] xhci_hcd 0000:00:14.0: resume root hub
[  445.824651] xhci_hcd 0000:00:14.0: handle_port_status: starting usb1 port polling.
[  445.844039] xhci_hcd 0000:00:14.0: PM: pci_pm_suspend(): hcd_pci_suspend+0x0/0x20 returns -16
[  445.844058] xhci_hcd 0000:00:14.0: PM: dpm_run_callback(): pci_pm_suspend+0x0/0x1c0 returns -16
[  445.844072] xhci_hcd 0000:00:14.0: PM: failed to suspend async: error -16
[  446.276101] PM: Some devices failed to suspend, or early wake event detected

So add a quirk to make sure the following is happening:
1. Let the i915 driver suspend first, to ensure the display is off so
   system also cuts the USB touchscreen's power.
2. Wait a while to let the USB disconnect event fire and get handled.
3. Since the disconnect event already happened, the xhci's suspend
   routine won't be interrupted anymore.

Signed-off-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
(cherry picked from commit https://lore.kernel.org/platform-driver-x86/20240906053047.459036-1-kai.heng.feng@canonical.com/T/#m1b1f48fea9626a4fb5f199ef2304d2f61ed43f52)
Signed-off-by: Chris Chiu <chris.chiu at canonical.com>
---
 drivers/platform/x86/hp/hp-wmi.c | 59 +++++++++++++++++++++++++++++++-
 1 file changed, 58 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/hp/hp-wmi.c b/drivers/platform/x86/hp/hp-wmi.c
index e536604225c5..0f3499d444fb 100644
--- a/drivers/platform/x86/hp/hp-wmi.c
+++ b/drivers/platform/x86/hp/hp-wmi.c
@@ -27,6 +27,8 @@
 #include <linux/rfkill.h>
 #include <linux/string.h>
 #include <linux/dmi.h>
+#include <linux/delay.h>
+#include <linux/pci.h>
 
 MODULE_AUTHOR("Matthew Garrett <mjg59 at srcf.ucam.org>");
 MODULE_DESCRIPTION("HP laptop WMI hotkeys driver");
@@ -1504,6 +1506,14 @@ static void __exit hp_wmi_bios_remove(struct platform_device *device)
 		platform_profile_remove();
 }
 
+static int hp_wmi_suspend_handler(struct device *device)
+{
+	/* Let the xhci have time to handle disconnect event */
+	msleep(200);
+
+	return 0;
+}
+
 static int hp_wmi_resume_handler(struct device *device)
 {
 	/*
@@ -1541,7 +1551,7 @@ static int hp_wmi_resume_handler(struct device *device)
 	return 0;
 }
 
-static const struct dev_pm_ops hp_wmi_pm_ops = {
+static struct dev_pm_ops hp_wmi_pm_ops = {
 	.resume  = hp_wmi_resume_handler,
 	.restore  = hp_wmi_resume_handler,
 };
@@ -1667,6 +1677,51 @@ static int hp_wmi_hwmon_init(void)
 	return 0;
 }
 
+static int lg_usb_touchscreen_quirk(const struct dmi_system_id *id)
+{
+	struct pci_dev *vga, *xhci;
+	struct device_link *vga_link, *xhci_link;
+
+	vga = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
+
+	xhci = pci_get_class(PCI_CLASS_SERIAL_USB_XHCI, NULL);
+
+	if (vga && xhci) {
+		xhci_link = device_link_add(&hp_wmi_platform_dev->dev, &xhci->dev,
+				      DL_FLAG_STATELESS);
+		if (xhci_link)
+			dev_dbg(&hp_wmi_platform_dev->dev, "Suspend before %s\n",
+				 pci_name(xhci));
+		else
+			return 1;
+
+		vga_link = device_link_add(&vga->dev, &hp_wmi_platform_dev->dev,
+					   DL_FLAG_STATELESS);
+		if (vga_link)
+			dev_dbg(&hp_wmi_platform_dev->dev, "Suspend after %s\n",
+				 pci_name(vga));
+		else {
+			device_link_del(xhci_link);
+			return 1;
+		}
+	}
+
+	hp_wmi_pm_ops.suspend = hp_wmi_suspend_handler;
+
+	return 1;
+}
+
+static const struct dmi_system_id hp_wmi_quirk_table[] = {
+	{
+		.callback = lg_usb_touchscreen_quirk,
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "HP ProOne 440 23.8 inch G9 All-in-One Desktop PC"),
+		},
+	},
+	{}
+};
+
 static int __init hp_wmi_init(void)
 {
 	int event_capable = wmi_has_guid(HPWMI_EVENT_GUID);
@@ -1699,6 +1754,8 @@ static int __init hp_wmi_init(void)
 			goto err_unregister_device;
 	}
 
+	dmi_check_system(hp_wmi_quirk_table);
+
 	return 0;
 
 err_unregister_device:
-- 
2.34.1