diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index 615ef81..e795cb8 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -893,13 +893,13 @@
 }
 
 /* wrapper to silence section mismatch warning */
-int __ref acpi_map_lsapic(acpi_handle handle, int physid, int *pcpu)
+int __ref acpi_map_cpu(acpi_handle handle, int physid, int *pcpu)
 {
 	return _acpi_map_lsapic(handle, physid, pcpu);
 }
-EXPORT_SYMBOL(acpi_map_lsapic);
+EXPORT_SYMBOL(acpi_map_cpu);
 
-int acpi_unmap_lsapic(int cpu)
+int acpi_unmap_cpu(int cpu)
 {
 	ia64_cpu_to_sapicid[cpu] = -1;
 	set_cpu_present(cpu, false);
@@ -910,8 +910,7 @@
 
 	return (0);
 }
-
-EXPORT_SYMBOL(acpi_unmap_lsapic);
+EXPORT_SYMBOL(acpi_unmap_cpu);
 #endif				/* CONFIG_ACPI_HOTPLUG_CPU */
 
 #ifdef CONFIG_ACPI_NUMA
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 4433a4b..d162636 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -750,13 +750,13 @@
 }
 
 /* wrapper to silence section mismatch warning */
-int __ref acpi_map_lsapic(acpi_handle handle, int physid, int *pcpu)
+int __ref acpi_map_cpu(acpi_handle handle, int physid, int *pcpu)
 {
 	return _acpi_map_lsapic(handle, physid, pcpu);
 }
-EXPORT_SYMBOL(acpi_map_lsapic);
+EXPORT_SYMBOL(acpi_map_cpu);
 
-int acpi_unmap_lsapic(int cpu)
+int acpi_unmap_cpu(int cpu)
 {
 #ifdef CONFIG_ACPI_NUMA
 	set_apicid_to_node(per_cpu(x86_cpu_to_apicid, cpu), NUMA_NO_NODE);
@@ -768,8 +768,7 @@
 
 	return (0);
 }
-
-EXPORT_SYMBOL(acpi_unmap_lsapic);
+EXPORT_SYMBOL(acpi_unmap_cpu);
 #endif				/* CONFIG_ACPI_HOTPLUG_CPU */
 
 int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base)
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 1fdf5e0..1020b1b 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -170,7 +170,7 @@
 	acpi_status status;
 	int ret;
 
-	if (pr->apic_id == -1)
+	if (pr->phys_id == -1)
 		return -ENODEV;
 
 	status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
@@ -180,13 +180,13 @@
 	cpu_maps_update_begin();
 	cpu_hotplug_begin();
 
-	ret = acpi_map_lsapic(pr->handle, pr->apic_id, &pr->id);
+	ret = acpi_map_cpu(pr->handle, pr->phys_id, &pr->id);
 	if (ret)
 		goto out;
 
 	ret = arch_register_cpu(pr->id);
 	if (ret) {
-		acpi_unmap_lsapic(pr->id);
+		acpi_unmap_cpu(pr->id);
 		goto out;
 	}
 
@@ -215,7 +215,7 @@
 	union acpi_object object = { 0 };
 	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 	struct acpi_processor *pr = acpi_driver_data(device);
-	int apic_id, cpu_index, device_declaration = 0;
+	int phys_id, cpu_index, device_declaration = 0;
 	acpi_status status = AE_OK;
 	static int cpu0_initialized;
 	unsigned long long value;
@@ -262,15 +262,18 @@
 		pr->acpi_id = value;
 	}
 
-	apic_id = acpi_get_apicid(pr->handle, device_declaration, pr->acpi_id);
-	if (apic_id < 0)
-		acpi_handle_debug(pr->handle, "failed to get CPU APIC ID.\n");
-	pr->apic_id = apic_id;
+	phys_id = acpi_get_phys_id(pr->handle, device_declaration, pr->acpi_id);
+	if (phys_id < 0)
+		acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
+	pr->phys_id = phys_id;
 
-	cpu_index = acpi_map_cpuid(pr->apic_id, pr->acpi_id);
+	cpu_index = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
 	if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
 		cpu0_initialized = 1;
-		/* Handle UP system running SMP kernel, with no LAPIC in MADT */
+		/*
+		 * Handle UP system running SMP kernel, with no CPU
+		 * entry in MADT
+		 */
 		if ((cpu_index == -1) && (num_online_cpus() == 1))
 			cpu_index = 0;
 	}
@@ -458,7 +461,7 @@
 
 	/* Remove the CPU. */
 	arch_unregister_cpu(pr->id);
-	acpi_unmap_lsapic(pr->id);
+	acpi_unmap_cpu(pr->id);
 
 	cpu_hotplug_done();
 	cpu_maps_update_done();
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index c2daa85..c0d44d3 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -257,7 +257,7 @@
 
 	device->power.state = ACPI_STATE_UNKNOWN;
 	if (!acpi_device_is_present(device))
-		return 0;
+		return -ENXIO;
 
 	result = acpi_device_get_power(device, &state);
 	if (result)
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 342942f..02e4839 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -69,7 +69,7 @@
 	unsigned long madt_end, entry;
 	static struct acpi_table_madt *madt;
 	static int read_madt;
-	int apic_id = -1;
+	int phys_id = -1;	/* CPU hardware ID */
 
 	if (!read_madt) {
 		if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
@@ -79,7 +79,7 @@
 	}
 
 	if (!madt)
-		return apic_id;
+		return phys_id;
 
 	entry = (unsigned long)madt;
 	madt_end = entry + madt->header.length;
@@ -91,18 +91,18 @@
 		struct acpi_subtable_header *header =
 			(struct acpi_subtable_header *)entry;
 		if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
-			if (!map_lapic_id(header, acpi_id, &apic_id))
+			if (!map_lapic_id(header, acpi_id, &phys_id))
 				break;
 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
-			if (!map_x2apic_id(header, type, acpi_id, &apic_id))
+			if (!map_x2apic_id(header, type, acpi_id, &phys_id))
 				break;
 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
-			if (!map_lsapic_id(header, type, acpi_id, &apic_id))
+			if (!map_lsapic_id(header, type, acpi_id, &phys_id))
 				break;
 		}
 		entry += header->length;
 	}
-	return apic_id;
+	return phys_id;
 }
 
 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
@@ -110,7 +110,7 @@
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	union acpi_object *obj;
 	struct acpi_subtable_header *header;
-	int apic_id = -1;
+	int phys_id = -1;
 
 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 		goto exit;
@@ -126,38 +126,38 @@
 
 	header = (struct acpi_subtable_header *)obj->buffer.pointer;
 	if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
-		map_lapic_id(header, acpi_id, &apic_id);
+		map_lapic_id(header, acpi_id, &phys_id);
 	else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
-		map_lsapic_id(header, type, acpi_id, &apic_id);
+		map_lsapic_id(header, type, acpi_id, &phys_id);
 	else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
-		map_x2apic_id(header, type, acpi_id, &apic_id);
+		map_x2apic_id(header, type, acpi_id, &phys_id);
 
 exit:
 	kfree(buffer.pointer);
-	return apic_id;
+	return phys_id;
 }
 
-int acpi_get_apicid(acpi_handle handle, int type, u32 acpi_id)
+int acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
 {
-	int apic_id;
+	int phys_id;
 
-	apic_id = map_mat_entry(handle, type, acpi_id);
-	if (apic_id == -1)
-		apic_id = map_madt_entry(type, acpi_id);
+	phys_id = map_mat_entry(handle, type, acpi_id);
+	if (phys_id == -1)
+		phys_id = map_madt_entry(type, acpi_id);
 
-	return apic_id;
+	return phys_id;
 }
 
-int acpi_map_cpuid(int apic_id, u32 acpi_id)
+int acpi_map_cpuid(int phys_id, u32 acpi_id)
 {
 #ifdef CONFIG_SMP
 	int i;
 #endif
 
-	if (apic_id == -1) {
+	if (phys_id == -1) {
 		/*
 		 * On UP processor, there is no _MAT or MADT table.
-		 * So above apic_id is always set to -1.
+		 * So above phys_id is always set to -1.
 		 *
 		 * BIOS may define multiple CPU handles even for UP processor.
 		 * For example,
@@ -170,7 +170,7 @@
 		 *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
 		 * }
 		 *
-		 * Ignores apic_id and always returns 0 for the processor
+		 * Ignores phys_id and always returns 0 for the processor
 		 * handle with acpi id 0 if nr_cpu_ids is 1.
 		 * This should be the case if SMP tables are not found.
 		 * Return -1 for other CPU's handle.
@@ -178,28 +178,28 @@
 		if (nr_cpu_ids <= 1 && acpi_id == 0)
 			return acpi_id;
 		else
-			return apic_id;
+			return phys_id;
 	}
 
 #ifdef CONFIG_SMP
 	for_each_possible_cpu(i) {
-		if (cpu_physical_id(i) == apic_id)
+		if (cpu_physical_id(i) == phys_id)
 			return i;
 	}
 #else
 	/* In UP kernel, only processor 0 is valid */
-	if (apic_id == 0)
-		return apic_id;
+	if (phys_id == 0)
+		return phys_id;
 #endif
 	return -1;
 }
 
 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 {
-	int apic_id;
+	int phys_id;
 
-	apic_id = acpi_get_apicid(handle, type, acpi_id);
+	phys_id = acpi_get_phys_id(handle, type, acpi_id);
 
-	return acpi_map_cpuid(apic_id, acpi_id);
+	return acpi_map_cpuid(phys_id, acpi_id);
 }
 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 16914cc..dc4d896 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1001,7 +1001,7 @@
 	if (device->wakeup.flags.valid)
 		acpi_power_resources_list_free(&device->wakeup.resources);
 
-	if (!device->flags.power_manageable)
+	if (!device->power.flags.power_resources)
 		return;
 
 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
@@ -1744,10 +1744,8 @@
 			device->power.flags.power_resources)
 		device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
 
-	if (acpi_bus_init_power(device)) {
-		acpi_free_power_resources_lists(device);
+	if (acpi_bus_init_power(device))
 		device->flags.power_manageable = 0;
-	}
 }
 
 static void acpi_bus_get_flags(struct acpi_device *device)
@@ -2371,13 +2369,18 @@
 	/* Skip devices that are not present. */
 	if (!acpi_device_is_present(device)) {
 		device->flags.visited = false;
+		device->flags.power_manageable = 0;
 		return;
 	}
 	if (device->handler)
 		goto ok;
 
 	if (!device->flags.initialized) {
-		acpi_bus_update_power(device, NULL);
+		device->flags.power_manageable =
+			device->power.states[ACPI_STATE_D0].flags.valid;
+		if (acpi_bus_init_power(device))
+			device->flags.power_manageable = 0;
+
 		device->flags.initialized = true;
 	}
 	device->flags.visited = false;
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index c72e79d2c5..032db45 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -522,6 +522,16 @@
 		DMI_MATCH(DMI_PRODUCT_NAME, "370R4E/370R4V/370R5E/3570RE/370R5V"),
 		},
 	},
+
+	{
+	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
+	 .callback = video_disable_native_backlight,
+	 .ident = "Dell XPS15 L521X",
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
+		},
+	},
 	{}
 };
 
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index 3ca9b75..b95dc32 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -196,8 +196,8 @@
 struct acpi_processor {
 	acpi_handle handle;
 	u32 acpi_id;
-	u32 apic_id;
-	u32 id;
+	u32 phys_id;	/* CPU hardware ID such as APIC ID for x86 */
+	u32 id;		/* CPU logical ID allocated by OS */
 	u32 pblk;
 	int performance_platform_limit;
 	int throttling_platform_limit;
@@ -310,8 +310,8 @@
 #endif				/* CONFIG_CPU_FREQ */
 
 /* in processor_core.c */
-int acpi_get_apicid(acpi_handle, int type, u32 acpi_id);
-int acpi_map_cpuid(int apic_id, u32 acpi_id);
+int acpi_get_phys_id(acpi_handle, int type, u32 acpi_id);
+int acpi_map_cpuid(int phys_id, u32 acpi_id);
 int acpi_get_cpuid(acpi_handle, int type, u32 acpi_id);
 
 /* in processor_pdc.c */
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 856d381..d459cd1 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -147,8 +147,8 @@
 
 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 /* Arch dependent functions for cpu hotplug support */
-int acpi_map_lsapic(acpi_handle handle, int physid, int *pcpu);
-int acpi_unmap_lsapic(int cpu);
+int acpi_map_cpu(acpi_handle handle, int physid, int *pcpu);
+int acpi_unmap_cpu(int cpu);
 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
 
 int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base);