platform/x86: huawei-wmi: Add quirks and module parameters

Introduce quirks and module parameters. 3 quirks are added:
1. Fixes reporting brightness keys twice since it's already handled by
   acpi-video.
2. Some models need a short delay when setting battery thresholds to
   prevent a race condition when two processes read/write. (will be used later)
3. Matebook X (2017) handles micmute led through the "legacy" interface
   which is not currently implemented. Use ACPI EC method to control
   this led. (will be used later)

2 module parameters are added to enable this short delay and/or report
  brightness keys through this driver.
Signed-off-by: Ayman Bagabas <ayman.bagabas@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

drivers/platform/x86/huawei-wmi.c

@@ -6,6 +6,7 @@
  */
 
 #include <linux/acpi.h>
+#include <linux/dmi.h>
 #include <linux/input.h>
 #include <linux/input/sparse-keymap.h>
 #include <linux/leds.h>
@@ -22,6 +23,14 @@
 #define WMI0_EXPENSIVE_GUID "39142400-C6A3-40fa-BADB-8A2652834100"
 #define WMI0_EVENT_GUID "59142400-C6A3-40fa-BADB-8A2652834100"
 
+struct quirk_entry {
+	bool battery_reset;
+	bool ec_micmute;
+	bool report_brightness;
+};
+
+static struct quirk_entry *quirks;
+
 struct huawei_wmi {
 	struct input_dev *idev[2];
 	struct led_classdev cdev;
@@ -49,6 +58,58 @@ static const struct key_entry huawei_wmi_keymap[] = {
 	{ KE_END,	 0 }
 };
 
+static int battery_reset = -1;
+static int report_brightness = -1;
+
+module_param(battery_reset, bint, 0444);
+MODULE_PARM_DESC(battery_reset,
+		"Reset battery charge values to (0-0) before disabling it using (0-100)");
+module_param(report_brightness, bint, 0444);
+MODULE_PARM_DESC(report_brightness,
+		"Report brightness keys.");
+
+/* Quirks */
+
+static int __init dmi_matched(const struct dmi_system_id *dmi)
+{
+	quirks = dmi->driver_data;
+	return 1;
+}
+
+static struct quirk_entry quirk_unknown = {
+};
+
+static struct quirk_entry quirk_battery_reset = {
+	.battery_reset = true,
+};
+
+static struct quirk_entry quirk_matebook_x = {
+	.ec_micmute = true,
+	.report_brightness = true,
+};
+
+static const struct dmi_system_id huawei_quirks[] = {
+	{
+		.callback = dmi_matched,
+		.ident = "Huawei MACH-WX9",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "HUAWEI"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "MACH-WX9"),
+		},
+		.driver_data = &quirk_battery_reset
+	},
+	{
+		.callback = dmi_matched,
+		.ident = "Huawei MateBook X",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "HUAWEI"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "HUAWEI MateBook X")
+		},
+		.driver_data = &quirk_matebook_x
+	},
+	{  }
+};
+
 static int huawei_wmi_micmute_led_set(struct led_classdev *led_cdev,
 		enum led_brightness brightness)
 {
@@ -139,6 +200,11 @@ static void huawei_wmi_process_key(struct input_dev *idev, int code)
 		return;
 	}
 
+	if (quirks && !quirks->report_brightness &&
+			(key->sw.code == KEY_BRIGHTNESSDOWN ||
+			key->sw.code == KEY_BRIGHTNESSUP))
+		return;
+
 	sparse_keymap_report_entry(idev, key, 1, true);
 }
 
@@ -253,6 +319,13 @@ static __init int huawei_wmi_init(void)
 	if (!huawei_wmi)
 		return -ENOMEM;
 
+	quirks = &quirk_unknown;
+	dmi_check_system(huawei_quirks);
+	if (battery_reset != -1)
+		quirks->battery_reset = battery_reset;
+	if (report_brightness != -1)
+		quirks->report_brightness = report_brightness;
+
 	err = platform_driver_register(&huawei_wmi_driver);
 	if (err)
 		goto pdrv_err;