diff --git a/drivers/acpi/ac.c b/drivers/acpi/ac.c
index e7515aa43d6bd62c3ec0e33fb6781d2a9f2f27a7..6f190bc2b8b784bf7e09425b77c560fa60f04b90 100644
--- a/drivers/acpi/ac.c
+++ b/drivers/acpi/ac.c
@@ -243,6 +243,8 @@ static int acpi_ac_resume(struct device *dev)
 		kobject_uevent(&ac->charger.dev->kobj, KOBJ_CHANGE);
 	return 0;
 }
+#else
+#define acpi_ac_resume NULL
 #endif
 static SIMPLE_DEV_PM_OPS(acpi_ac_pm_ops, NULL, acpi_ac_resume);
 
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 018a4288370630cb40203ecd43cc2809851288ae..797a6938d0515edb7ce7e5ce3f4f1648c538e515 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -841,6 +841,8 @@ static int acpi_battery_resume(struct device *dev)
 	acpi_battery_update(battery);
 	return 0;
 }
+#else
+#define acpi_battery_resume NULL
 #endif
 
 static SIMPLE_DEV_PM_OPS(acpi_battery_pm, NULL, acpi_battery_resume);
diff --git a/drivers/acpi/blacklist.c b/drivers/acpi/blacklist.c
index 10e4964d051a9c295e6185db1cfebe20b0ce5a9d..afec4526c48aa04e2921a199396e8fb2ea7489be 100644
--- a/drivers/acpi/blacklist.c
+++ b/drivers/acpi/blacklist.c
@@ -260,14 +260,6 @@ static struct dmi_system_id acpi_osi_dmi_table[] __initdata = {
 	},
 	{
 	.callback = dmi_disable_osi_win8,
-	.ident = "Dell Inspiron 15R SE",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7520"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
 	.ident = "ThinkPad Edge E530",
 	.matches = {
 		     DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
@@ -322,56 +314,6 @@ static struct dmi_system_id acpi_osi_dmi_table[] __initdata = {
 		     DMI_MATCH(DMI_PRODUCT_VERSION, "2349D15"),
 		},
 	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "HP ProBook 2013 models",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "HP ProBook "),
-		     DMI_MATCH(DMI_PRODUCT_NAME, " G1"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "HP EliteBook 2013 models",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook "),
-		     DMI_MATCH(DMI_PRODUCT_NAME, " G1"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "HP ZBook 14",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 14"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "HP ZBook 15",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 15"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "HP ZBook 17",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 17"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "HP EliteBook 8780w",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook 8780w"),
-		},
-	},
 
 	/*
 	 * BIOS invocation of _OSI(Linux) is almost always a BIOS bug.
diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
index 11c11f6b8fa1453a4a28c3931f0cf8618750fecc..714e957a871a8034ed18be2104b8c107d0b4ced9 100644
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -80,6 +80,8 @@ static void acpi_button_notify(struct acpi_device *device, u32 event);
 
 #ifdef CONFIG_PM_SLEEP
 static int acpi_button_resume(struct device *dev);
+#else
+#define acpi_button_resume NULL
 #endif
 static SIMPLE_DEV_PM_OPS(acpi_button_pm, NULL, acpi_button_resume);
 
diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c
index e9b3081c4fe994bdfd7dcba5b54ae0533cf8f110..5bfd769fc91fa5bfd0890a146a4eed13ac342ff0 100644
--- a/drivers/acpi/dock.c
+++ b/drivers/acpi/dock.c
@@ -713,13 +713,11 @@ static acpi_status __init find_dock_devices(acpi_handle handle, u32 lvl,
 static ssize_t show_docked(struct device *dev,
 			   struct device_attribute *attr, char *buf)
 {
-	struct acpi_device *tmp;
-
 	struct dock_station *dock_station = dev->platform_data;
+	struct acpi_device *adev = NULL;
 
-	if (!acpi_bus_get_device(dock_station->handle, &tmp))
-		return snprintf(buf, PAGE_SIZE, "1\n");
-	return snprintf(buf, PAGE_SIZE, "0\n");
+	acpi_bus_get_device(dock_station->handle, &adev);
+	return snprintf(buf, PAGE_SIZE, "%u\n", acpi_device_enumerated(adev));
 }
 static DEVICE_ATTR(docked, S_IRUGO, show_docked, NULL);
 
diff --git a/drivers/acpi/fan.c b/drivers/acpi/fan.c
index 1fb62900f32a9c57d329fd3e5480bc0dc7c305b8..09e423f3d8ad30fbd16d2d2b2e2766e69e64de82 100644
--- a/drivers/acpi/fan.c
+++ b/drivers/acpi/fan.c
@@ -55,6 +55,9 @@ MODULE_DEVICE_TABLE(acpi, fan_device_ids);
 #ifdef CONFIG_PM_SLEEP
 static int acpi_fan_suspend(struct device *dev);
 static int acpi_fan_resume(struct device *dev);
+#else
+#define acpi_fan_suspend NULL
+#define acpi_fan_resume NULL
 #endif
 static SIMPLE_DEV_PM_OPS(acpi_fan_pm, acpi_fan_suspend, acpi_fan_resume);
 
diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c
index 52d45ea2bc4f63efcfb7e8912b087b1a568d49cc..361b40c10c3f522e28e2b334dd5f8976109bc772 100644
--- a/drivers/acpi/pci_irq.c
+++ b/drivers/acpi/pci_irq.c
@@ -430,6 +430,7 @@ int acpi_pci_irq_enable(struct pci_dev *dev)
 				 pin_name(pin));
 		}
 
+		kfree(entry);
 		return 0;
 	}
 
diff --git a/drivers/acpi/sbs.c b/drivers/acpi/sbs.c
index d465ae6cdd004b9813cc333529c54ef29abcb16f..dbd48498b93863a1fa37ab0b23706f2dae89345d 100644
--- a/drivers/acpi/sbs.c
+++ b/drivers/acpi/sbs.c
@@ -450,7 +450,7 @@ static ssize_t acpi_battery_alarm_store(struct device *dev,
 {
 	unsigned long x;
 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
-	if (sscanf(buf, "%ld\n", &x) == 1)
+	if (sscanf(buf, "%lu\n", &x) == 1)
 		battery->alarm_capacity = x /
 			(1000 * acpi_battery_scale(battery));
 	if (battery->present)
@@ -668,6 +668,8 @@ static int acpi_sbs_resume(struct device *dev)
 	acpi_sbs_callback(sbs);
 	return 0;
 }
+#else
+#define acpi_sbs_resume NULL
 #endif
 
 static SIMPLE_DEV_PM_OPS(acpi_sbs_pm, NULL, acpi_sbs_resume);
diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 8349a555b92b8aa6d6584f9c2c5c9ccf7a27737f..08626c851be7eef72c5a639522b708586736adc5 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -102,6 +102,8 @@ MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
 
 #ifdef CONFIG_PM_SLEEP
 static int acpi_thermal_resume(struct device *dev);
+#else
+#define acpi_thermal_resume NULL
 #endif
 static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, NULL, acpi_thermal_resume);
 
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index b727d105046d234ae8ef2a5669e53e61b82e7123..b6ba88ed31aeeb1854e48bb73b95fc59a4d58706 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -81,11 +81,12 @@ static bool allow_duplicates;
 module_param(allow_duplicates, bool, 0644);
 
 /*
- * For Windows 8 systems: if set ture and the GPU driver has
- * registered a backlight interface, skip registering ACPI video's.
+ * For Windows 8 systems: used to decide if video module
+ * should skip registering backlight interface of its own.
  */
-static bool use_native_backlight = false;
-module_param(use_native_backlight, bool, 0644);
+static int use_native_backlight_param = -1;
+module_param_named(use_native_backlight, use_native_backlight_param, int, 0444);
+static bool use_native_backlight_dmi = false;
 
 static int register_count;
 static struct mutex video_list_lock;
@@ -231,9 +232,17 @@ static int acpi_video_get_next_level(struct acpi_video_device *device,
 static int acpi_video_switch_brightness(struct acpi_video_device *device,
 					 int event);
 
+static bool acpi_video_use_native_backlight(void)
+{
+	if (use_native_backlight_param != -1)
+		return use_native_backlight_param;
+	else
+		return use_native_backlight_dmi;
+}
+
 static bool acpi_video_verify_backlight_support(void)
 {
-	if (acpi_osi_is_win8() && use_native_backlight &&
+	if (acpi_osi_is_win8() && acpi_video_use_native_backlight() &&
 	    backlight_device_registered(BACKLIGHT_RAW))
 		return false;
 	return acpi_video_backlight_support();
@@ -398,6 +407,12 @@ static int __init video_set_bqc_offset(const struct dmi_system_id *d)
 	return 0;
 }
 
+static int __init video_set_use_native_backlight(const struct dmi_system_id *d)
+{
+	use_native_backlight_dmi = true;
+	return 0;
+}
+
 static struct dmi_system_id video_dmi_table[] __initdata = {
 	/*
 	 * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
@@ -442,6 +457,120 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
 		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 		},
 	},
+	{
+	 .callback = video_set_use_native_backlight,
+	 .ident = "ThinkPad T430s",
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T430s"),
+		},
+	},
+	{
+	 .callback = video_set_use_native_backlight,
+	 .ident = "ThinkPad X230",
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X230"),
+		},
+	},
+	{
+	.callback = video_set_use_native_backlight,
+	.ident = "ThinkPad X1 Carbon",
+	.matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X1 Carbon"),
+		},
+	},
+	{
+	 .callback = video_set_use_native_backlight,
+	 .ident = "Lenovo Yoga 13",
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+		DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Yoga 13"),
+		},
+	},
+	{
+	 .callback = video_set_use_native_backlight,
+	 .ident = "Dell Inspiron 7520",
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+		DMI_MATCH(DMI_PRODUCT_VERSION, "Inspiron 7520"),
+		},
+	},
+	{
+	 .callback = video_set_use_native_backlight,
+	 .ident = "Acer Aspire 5733Z",
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5733Z"),
+		},
+	},
+	{
+	 .callback = video_set_use_native_backlight,
+	 .ident = "Acer Aspire V5-431",
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-431"),
+		},
+	},
+	{
+	.callback = video_set_use_native_backlight,
+	.ident = "HP ProBook 4340s",
+	.matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		DMI_MATCH(DMI_PRODUCT_VERSION, "HP ProBook 4340s"),
+		},
+	},
+	{
+	.callback = video_set_use_native_backlight,
+	.ident = "HP ProBook 2013 models",
+	.matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		DMI_MATCH(DMI_PRODUCT_NAME, "HP ProBook "),
+		DMI_MATCH(DMI_PRODUCT_NAME, " G1"),
+		},
+	},
+	{
+	.callback = video_set_use_native_backlight,
+	.ident = "HP EliteBook 2013 models",
+	.matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook "),
+		DMI_MATCH(DMI_PRODUCT_NAME, " G1"),
+		},
+	},
+	{
+	.callback = video_set_use_native_backlight,
+	.ident = "HP ZBook 14",
+	.matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 14"),
+		},
+	},
+	{
+	.callback = video_set_use_native_backlight,
+	.ident = "HP ZBook 15",
+	.matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 15"),
+		},
+	},
+	{
+	.callback = video_set_use_native_backlight,
+	.ident = "HP ZBook 17",
+	.matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 17"),
+		},
+	},
+	{
+	.callback = video_set_use_native_backlight,
+	.ident = "HP EliteBook 8780w",
+	.matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook 8780w"),
+		},
+	},
 	{}
 };
 
@@ -685,6 +814,7 @@ acpi_video_init_brightness(struct acpi_video_device *device)
 	union acpi_object *o;
 	struct acpi_video_device_brightness *br = NULL;
 	int result = -EINVAL;
+	u32 value;
 
 	if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
@@ -715,7 +845,12 @@ acpi_video_init_brightness(struct acpi_video_device *device)
 			printk(KERN_ERR PREFIX "Invalid data\n");
 			continue;
 		}
-		br->levels[count] = (u32) o->integer.value;
+		value = (u32) o->integer.value;
+		/* Skip duplicate entries */
+		if (count > 2 && br->levels[count - 1] == value)
+			continue;
+
+		br->levels[count] = value;
 
 		if (br->levels[count] > max_level)
 			max_level = br->levels[count];
diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
index a697b77b8865a163cd23fe591db0242631ca742f..19080c8e2f2a9c6d5df7f5475d581f5348ed9e8e 100644
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -168,22 +168,6 @@ static struct dmi_system_id video_detect_dmi_table[] = {
 		DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
 		},
 	},
-	{
-	.callback = video_detect_force_vendor,
-	.ident = "HP EliteBook Revolve 810",
-	.matches = {
-		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook Revolve 810 G1"),
-		},
-	},
-	{
-	.callback = video_detect_force_vendor,
-	.ident = "Lenovo Yoga 13",
-	.matches = {
-		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
-		DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Yoga 13"),
-		},
-	},
 	{ },
 };
 
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 08ca8c9f41cdeb27f6e4bb4879b2912798e1a72e..cb003a6b72c86f10f31afd0d7b3c156308f95acc 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1323,8 +1323,7 @@ static int __cpufreq_remove_dev_prepare(struct device *dev,
 	up_read(&policy->rwsem);
 
 	if (cpu != policy->cpu) {
-		if (!frozen)
-			sysfs_remove_link(&dev->kobj, "cpufreq");
+		sysfs_remove_link(&dev->kobj, "cpufreq");
 	} else if (cpus > 1) {
 		new_cpu = cpufreq_nominate_new_policy_cpu(policy, cpu);
 		if (new_cpu >= 0) {
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index c788abf1c457cea63c1b60b7bbff637e5b303228..e908161059216b286123948d3de3405da450d3b8 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -34,8 +34,10 @@
 
 #define SAMPLE_COUNT		3
 
-#define BYT_RATIOS	0x66a
-#define BYT_VIDS        0x66b
+#define BYT_RATIOS		0x66a
+#define BYT_VIDS		0x66b
+#define BYT_TURBO_RATIOS	0x66c
+
 
 #define FRAC_BITS 8
 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
@@ -357,7 +359,7 @@ static int byt_get_min_pstate(void)
 {
 	u64 value;
 	rdmsrl(BYT_RATIOS, value);
-	return value & 0xFF;
+	return (value >> 8) & 0xFF;
 }
 
 static int byt_get_max_pstate(void)
@@ -367,6 +369,13 @@ static int byt_get_max_pstate(void)
 	return (value >> 16) & 0xFF;
 }
 
+static int byt_get_turbo_pstate(void)
+{
+	u64 value;
+	rdmsrl(BYT_TURBO_RATIOS, value);
+	return value & 0x3F;
+}
+
 static void byt_set_pstate(struct cpudata *cpudata, int pstate)
 {
 	u64 val;
@@ -469,7 +478,7 @@ static struct cpu_defaults byt_params = {
 	.funcs = {
 		.get_max = byt_get_max_pstate,
 		.get_min = byt_get_min_pstate,
-		.get_turbo = byt_get_max_pstate,
+		.get_turbo = byt_get_turbo_pstate,
 		.set = byt_set_pstate,
 		.get_vid = byt_get_vid,
 	},
diff --git a/drivers/cpufreq/powernow-k8.c b/drivers/cpufreq/powernow-k8.c
index e10b646634d77ff3a4bcf0c54d154a91c7c35805..6684e0342792517577fde32d56542b3ad84d15af 100644
--- a/drivers/cpufreq/powernow-k8.c
+++ b/drivers/cpufreq/powernow-k8.c
@@ -1076,7 +1076,7 @@ static int powernowk8_cpu_init(struct cpufreq_policy *pol)
 {
 	struct powernow_k8_data *data;
 	struct init_on_cpu init_on_cpu;
-	int rc;
+	int rc, cpu;
 
 	smp_call_function_single(pol->cpu, check_supported_cpu, &rc, 1);
 	if (rc)
@@ -1140,7 +1140,9 @@ static int powernowk8_cpu_init(struct cpufreq_policy *pol)
 	pr_debug("cpu_init done, current fid 0x%x, vid 0x%x\n",
 		 data->currfid, data->currvid);
 
-	per_cpu(powernow_data, pol->cpu) = data;
+	/* Point all the CPUs in this policy to the same data */
+	for_each_cpu(cpu, pol->cpus)
+		per_cpu(powernow_data, cpu) = data;
 
 	return 0;
 
@@ -1155,6 +1157,7 @@ static int powernowk8_cpu_init(struct cpufreq_policy *pol)
 static int powernowk8_cpu_exit(struct cpufreq_policy *pol)
 {
 	struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
+	int cpu;
 
 	if (!data)
 		return -EINVAL;
@@ -1165,7 +1168,8 @@ static int powernowk8_cpu_exit(struct cpufreq_policy *pol)
 
 	kfree(data->powernow_table);
 	kfree(data);
-	per_cpu(powernow_data, pol->cpu) = NULL;
+	for_each_cpu(cpu, pol->cpus)
+		per_cpu(powernow_data, cpu) = NULL;
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.c b/drivers/gpu/drm/nouveau/nouveau_acpi.c
index 4ef83df2b246fb335dc8ce05bafead80ed7ac180..83face3f608f020f70d7d11dda363c5817102238 100644
--- a/drivers/gpu/drm/nouveau/nouveau_acpi.c
+++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c
@@ -106,6 +106,29 @@ static int nouveau_optimus_dsm(acpi_handle handle, int func, int arg, uint32_t *
 	return 0;
 }
 
+/*
+ * On some platforms, _DSM(nouveau_op_dsm_muid, func0) has special
+ * requirements on the fourth parameter, so a private implementation
+ * instead of using acpi_check_dsm().
+ */
+static int nouveau_check_optimus_dsm(acpi_handle handle)
+{
+	int result;
+
+	/*
+	 * Function 0 returns a Buffer containing available functions.
+	 * The args parameter is ignored for function 0, so just put 0 in it
+	 */
+	if (nouveau_optimus_dsm(handle, 0, 0, &result))
+		return 0;
+
+	/*
+	 * ACPI Spec v4 9.14.1: if bit 0 is zero, no function is supported.
+	 * If the n-th bit is enabled, function n is supported
+	 */
+	return result & 1 && result & (1 << NOUVEAU_DSM_OPTIMUS_CAPS);
+}
+
 static int nouveau_dsm(acpi_handle handle, int func, int arg)
 {
 	int ret = 0;
@@ -207,8 +230,7 @@ static int nouveau_dsm_pci_probe(struct pci_dev *pdev)
 			   1 << NOUVEAU_DSM_POWER))
 		retval |= NOUVEAU_DSM_HAS_MUX;
 
-	if (acpi_check_dsm(dhandle, nouveau_op_dsm_muid, 0x00000100,
-			   1 << NOUVEAU_DSM_OPTIMUS_CAPS))
+	if (nouveau_check_optimus_dsm(dhandle))
 		retval |= NOUVEAU_DSM_HAS_OPT;
 
 	if (retval & NOUVEAU_DSM_HAS_OPT) {