alienware-wmi: Add support for deep sleep control.

Allow for user configuration of BIOS settings that allow the system to be
turned on via HID devices.

The feature requires hardware architectural modifications and can not be
supported on existing systems.
Signed-off-by: Mario Limonciello <mario_limonciello@dell.com>
[dvhart: comment formatting and line length fixes]
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

drivers/platform/x86/alienware-wmi.c

@@ -34,6 +34,8 @@
 #define WMAX_METHOD_ZONE_CONTROL	0x4
 #define WMAX_METHOD_HDMI_CABLE		0x5
 #define WMAX_METHOD_AMPLIFIER_CABLE	0x6
+#define WMAX_METHOD_DEEP_SLEEP_CONTROL	0x0B
+#define WMAX_METHOD_DEEP_SLEEP_STATUS	0x0C
 
 MODULE_AUTHOR("Mario Limonciello <mario_limonciello@dell.com>");
 MODULE_DESCRIPTION("Alienware special feature control");
@@ -62,6 +64,7 @@ struct quirk_entry {
 	u8 num_zones;
 	u8 hdmi_mux;
 	u8 amplifier;
+	u8 deepslp;
 };
 
 static struct quirk_entry *quirks;
@@ -70,24 +73,28 @@ static struct quirk_entry quirk_unknown = {
 	.num_zones = 2,
 	.hdmi_mux = 0,
 	.amplifier = 0,
+	.deepslp = 0,
 };
 
 static struct quirk_entry quirk_x51_r1_r2 = {
 	.num_zones = 3,
 	.hdmi_mux = 0,
 	.amplifier = 0,
+	.deepslp = 0,
 };
 
 static struct quirk_entry quirk_x51_r3 = {
 	.num_zones = 4,
 	.hdmi_mux = 0,
 	.amplifier = 1,
+	.deepslp = 0,
 };
 
 static struct quirk_entry quirk_asm100 = {
 	.num_zones = 2,
 	.hdmi_mux = 1,
 	.amplifier = 0,
+	.deepslp = 0,
 };
 
 static int __init dmi_matched(const struct dmi_system_id *dmi)
@@ -647,6 +654,87 @@ static int create_amplifier(struct platform_device *dev)
 	return ret;
 }
 
+/*
+ * Deep Sleep Control support
+ * - Modifies BIOS setting for deep sleep control allowing extra wakeup events
+ */
+static ssize_t show_deepsleep_status(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	acpi_status status;
+	u32 out_data;
+	struct wmax_basic_args in_args = {
+		.arg = 0,
+	};
+	status = alienware_wmax_command(&in_args, WMAX_METHOD_DEEP_SLEEP_STATUS,
+					(u32 *) &out_data);
+	if (ACPI_SUCCESS(status)) {
+		if (out_data == 0)
+			return scnprintf(buf, PAGE_SIZE,
+					 "[disabled] s5 s5_s4\n");
+		else if (out_data == 1)
+			return scnprintf(buf, PAGE_SIZE,
+					 "disabled [s5] s5_s4\n");
+		else if (out_data == 2)
+			return scnprintf(buf, PAGE_SIZE,
+					 "disabled s5 [s5_s4]\n");
+	}
+	pr_err("alienware-wmi: unknown deep sleep status: %d\n", status);
+	return scnprintf(buf, PAGE_SIZE, "disabled s5 s5_s4 [unknown]\n");
+}
+
+static ssize_t toggle_deepsleep(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	acpi_status status;
+	struct wmax_basic_args args;
+
+	if (strcmp(buf, "disabled\n") == 0)
+		args.arg = 0;
+	else if (strcmp(buf, "s5\n") == 0)
+		args.arg = 1;
+	else
+		args.arg = 2;
+	pr_debug("alienware-wmi: setting deep sleep to %d : %s", args.arg, buf);
+
+	status = alienware_wmax_command(&args, WMAX_METHOD_DEEP_SLEEP_CONTROL,
+					NULL);
+
+	if (ACPI_FAILURE(status))
+		pr_err("alienware-wmi: deep sleep control failed: results: %u\n",
+			status);
+	return count;
+}
+
+static DEVICE_ATTR(deepsleep, S_IRUGO | S_IWUSR, show_deepsleep_status, toggle_deepsleep);
+
+static struct attribute *deepsleep_attrs[] = {
+	&dev_attr_deepsleep.attr,
+	NULL,
+};
+
+static struct attribute_group deepsleep_attribute_group = {
+	.name = "deepsleep",
+	.attrs = deepsleep_attrs,
+};
+
+static void remove_deepsleep(struct platform_device *dev)
+{
+	if (quirks->deepslp > 0)
+		sysfs_remove_group(&dev->dev.kobj, &deepsleep_attribute_group);
+}
+
+static int create_deepsleep(struct platform_device *dev)
+{
+	int ret;
+
+	ret = sysfs_create_group(&dev->dev.kobj, &deepsleep_attribute_group);
+	if (ret)
+		remove_deepsleep(dev);
+	return ret;
+}
+
 static int __init alienware_wmi_init(void)
 {
 	int ret;
@@ -688,6 +776,12 @@ static int __init alienware_wmi_init(void)
 			goto fail_prep_amplifier;
 	}
 
+	if (quirks->deepslp > 0) {
+		ret = create_deepsleep(platform_device);
+		if (ret)
+			goto fail_prep_deepsleep;
+	}
+
 	ret = alienware_zone_init(platform_device);
 	if (ret)
 		goto fail_prep_zones;
@@ -696,6 +790,7 @@ static int __init alienware_wmi_init(void)
 
 fail_prep_zones:
 	alienware_zone_exit(platform_device);
+fail_prep_deepsleep:
 fail_prep_amplifier:
 fail_prep_hdmi:
 	platform_device_del(platform_device);