platform/x86: x86-android-tablets: Add support for the Dolby button on Peaq C1010

The Peaq C1010 tablet has a special "Dolby" button. This button has
a WMI interface, but this is broken in several ways:

1. It only supports polling
2. The value read on polling goes from 0 -> 1 for one poll on both edges
   of the button, with no way to tell which edge causes the poll to
   return 1.
3. It uses a non unique GUID (it uses the Microsoft docs WMI example GUID).

There currently is a WMI driver for this, but it uses several kludges
to work around these issues and is not entirely reliable due to 2.

Replace the unreliable WMI driver by using the x86-android-tablets code
to instantiate a gpio_keys device for this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20230301092331.7038-11-hdegoede@redhat.com

1 files changed, 0 insertions, 128 deletions

diff --git a/drivers/platform/x86/peaq-wmi.c b/drivers/platform/x86/peaq-wmi.c
deleted file mode 100644
index cf9c44c20a82..000000000000
--- a/drivers/platform/x86/peaq-wmi.c
+++ /dev/null
@@ -1,128 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * PEAQ 2-in-1 WMI hotkey driver
- * Copyright (C) 2017 Hans de Goede <hdegoede@redhat.com>
- */
-
-#include <linux/acpi.h>
-#include <linux/dmi.h>
-#include <linux/input.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-
-#define PEAQ_DOLBY_BUTTON_GUID		"ABBC0F6F-8EA1-11D1-00A0-C90629100000"
-#define PEAQ_DOLBY_BUTTON_METHOD_ID	5
-#define PEAQ_POLL_INTERVAL_MS		250
-#define PEAQ_POLL_IGNORE_MS		500
-#define PEAQ_POLL_MAX_MS		1000
-
-MODULE_ALIAS("wmi:"PEAQ_DOLBY_BUTTON_GUID);
-
-static struct input_dev *peaq_poll_dev;
-
-/*
- * The Dolby button (yes really a Dolby button) causes an ACPI variable to get
- * set on both press and release. The WMI method checks and clears that flag.
- * So for a press + release we will get back One from the WMI method either once
- * (if polling after the release) or twice (polling between press and release).
- * We ignore events for 0.5s after the first event to avoid reporting 2 presses.
- */
-static void peaq_wmi_poll(struct input_dev *input_dev)
-{
-	static unsigned long last_event_time;
-	static bool had_events;
-	union acpi_object obj;
-	acpi_status status;
-	u32 dummy = 0;
-
-	struct acpi_buffer input = { sizeof(dummy), &dummy };
-	struct acpi_buffer output = { sizeof(obj), &obj };
-
-	status = wmi_evaluate_method(PEAQ_DOLBY_BUTTON_GUID, 0,
-				     PEAQ_DOLBY_BUTTON_METHOD_ID,
-				     &input, &output);
-	if (ACPI_FAILURE(status))
-		return;
-
-	if (obj.type != ACPI_TYPE_INTEGER) {
-		dev_err(&input_dev->dev,
-			"Error WMBC did not return an integer\n");
-		return;
-	}
-
-	if (!obj.integer.value)
-		return;
-
-	if (had_events && time_before(jiffies, last_event_time +
-					msecs_to_jiffies(PEAQ_POLL_IGNORE_MS)))
-		return;
-
-	input_event(input_dev, EV_KEY, KEY_SOUND, 1);
-	input_sync(input_dev);
-	input_event(input_dev, EV_KEY, KEY_SOUND, 0);
-	input_sync(input_dev);
-
-	last_event_time = jiffies;
-	had_events = true;
-}
-
-/* Some other devices (Shuttle XS35) use the same WMI GUID for other purposes */
-static const struct dmi_system_id peaq_dmi_table[] __initconst = {
-	{
-		.matches = {
-			DMI_MATCH(DMI_SYS_VENDOR, "PEAQ"),
-			DMI_MATCH(DMI_PRODUCT_NAME, "PEAQ PMM C1010 MD99187"),
-		},
-	},
-	{}
-};
-
-static int __init peaq_wmi_init(void)
-{
-	int err;
-
-	/* WMI GUID is not unique, also check for a DMI match */
-	if (!dmi_check_system(peaq_dmi_table))
-		return -ENODEV;
-
-	if (!wmi_has_guid(PEAQ_DOLBY_BUTTON_GUID))
-		return -ENODEV;
-
-	peaq_poll_dev = input_allocate_device();
-	if (!peaq_poll_dev)
-		return -ENOMEM;
-
-	peaq_poll_dev->name = "PEAQ WMI hotkeys";
-	peaq_poll_dev->phys = "wmi/input0";
-	peaq_poll_dev->id.bustype = BUS_HOST;
-	input_set_capability(peaq_poll_dev, EV_KEY, KEY_SOUND);
-
-	err = input_setup_polling(peaq_poll_dev, peaq_wmi_poll);
-	if (err)
-		goto err_out;
-
-	input_set_poll_interval(peaq_poll_dev, PEAQ_POLL_INTERVAL_MS);
-	input_set_max_poll_interval(peaq_poll_dev, PEAQ_POLL_MAX_MS);
-
-	err = input_register_device(peaq_poll_dev);
-	if (err)
-		goto err_out;
-
-	return 0;
-
-err_out:
-	input_free_device(peaq_poll_dev);
-	return err;
-}
-
-static void __exit peaq_wmi_exit(void)
-{
-	input_unregister_device(peaq_poll_dev);
-}
-
-module_init(peaq_wmi_init);
-module_exit(peaq_wmi_exit);
-
-MODULE_DESCRIPTION("PEAQ 2-in-1 WMI hotkey driver");
-MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
-MODULE_LICENSE("GPL");