From aa23ca3d98f756d5b1e503fb140665fb24a41a38 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Sun, 5 Jan 2020 17:03:57 +0100
Subject: [PATCH] gpiolib: acpi: Add honor_wakeup module-option + quirk mechanism
Git-commit: aa23ca3d98f756d5b1e503fb140665fb24a41a38
Patch-mainline: v5.5-rc6
References: git-fixes

On some laptops enabling wakeup on the GPIO interrupts used for ACPI _AEI
event handling causes spurious wakeups.

This commit adds a new honor_wakeup option, defaulting to true (our current
behavior), which can be used to disable wakeup on troublesome hardware
to avoid these spurious wakeups.

This is a workaround for an architectural problem with s2idle under Linux
where we do not have any mechanism to immediately go back to sleep after
wakeup events, other then for embedded-controller events using the standard
ACPI EC interface, for details see:
https://lore.kernel.org/linux-acpi/61450f9b-cbc6-0c09-8b3a-aff6bf9a0b3c@redhat.com/

One series of laptops which is not able to suspend without this workaround
is the HP x2 10 Cherry Trail models, this commit adds a DMI based quirk
which makes sets honor_wakeup to false on these models.

Cc: stable@vger.kernel.org
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200105160357.97154-3-hdegoede@redhat.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpio/gpiolib-acpi.c |   32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -25,12 +25,18 @@
 #include "gpiolib.h"
 
 #define QUIRK_NO_EDGE_EVENTS_ON_BOOT		0x01l
+#define QUIRK_NO_WAKEUP				0x02l
 
 static int run_edge_events_on_boot = -1;
 module_param(run_edge_events_on_boot, int, 0444);
 MODULE_PARM_DESC(run_edge_events_on_boot,
 		 "Run edge _AEI event-handlers at boot: 0=no, 1=yes, -1=auto");
 
+static int honor_wakeup = -1;
+module_param(honor_wakeup, int, 0444);
+MODULE_PARM_DESC(honor_wakeup,
+		 "Honor the ACPI wake-capable flag: 0=no, 1=yes, -1=auto");
+
 /**
  * struct acpi_gpio_event - ACPI GPIO event handler data
  *
@@ -267,7 +273,7 @@ static acpi_status acpi_gpiochip_alloc_e
 	event->handle = evt_handle;
 	event->handler = handler;
 	event->irq = irq;
-	event->irq_is_wake = agpio->wake_capable == ACPI_WAKE_CAPABLE;
+	event->irq_is_wake = honor_wakeup && agpio->wake_capable == ACPI_WAKE_CAPABLE;
 	event->pin = pin;
 	event->desc = desc;
 
@@ -1233,6 +1239,23 @@ static const struct dmi_system_id gpioli
 		},
 		.driver_data = (void *)QUIRK_NO_EDGE_EVENTS_ON_BOOT,
 	},
+	{
+		/*
+		 * Various HP X2 10 Cherry Trail models use an external
+		 * embedded-controller connected via I2C + an ACPI GPIO
+		 * event handler. The embedded controller generates various
+		 * spurious wakeup events when suspended. So disable wakeup
+		 * for its handler (it uses the only ACPI GPIO event handler).
+		 * This breaks wakeup when opening the lid, the user needs
+		 * to press the power-button to wakeup the system. The
+		 * alternative is suspend simply not working, which is worse.
+		 */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "HP x2 Detachable 10-p0XX"),
+		},
+		.driver_data = (void *)QUIRK_NO_WAKEUP,
+	},
 	{} /* Terminating entry */
 };
 
@@ -1252,6 +1275,13 @@ static int acpi_gpio_setup_params(void)
 			run_edge_events_on_boot = 1;
 	}
 
+	if (honor_wakeup < 0) {
+		if (quirks & QUIRK_NO_WAKEUP)
+			honor_wakeup = 0;
+		else
+			honor_wakeup = 1;
+	}
+
 	return 0;
 }