ACPI: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through # [1]
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/ac.c

@@ -236,7 +236,7 @@ static void acpi_ac_notify(struct acpi_device *device, u32 event)
 	default:
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 				  "Unsupported event [0x%x]\n", event));
-	/* fall through */
+		fallthrough;
 	case ACPI_AC_NOTIFY_STATUS:
 	case ACPI_NOTIFY_BUS_CHECK:
 	case ACPI_NOTIFY_DEVICE_CHECK:

drivers/acpi/acpi_processor.c

@@ -79,7 +79,7 @@ static int acpi_processor_errata_piix4(struct pci_dev *dev)
 		 * PIIX4 models.
 		 */
 		errata.piix4.throttle = 1;
-		/* fall through*/
+		fallthrough;
 
 	case 2:		/* PIIX4E */
 	case 3:		/* PIIX4M */

drivers/acpi/button.c

@@ -405,7 +405,7 @@ static void acpi_button_notify(struct acpi_device *device, u32 event)
 	switch (event) {
 	case ACPI_FIXED_HARDWARE_EVENT:
 		event = ACPI_BUTTON_NOTIFY_STATUS;
-		/* fall through */
+		fallthrough;
 	case ACPI_BUTTON_NOTIFY_STATUS:
 		input = button->input;
 		if (button->type == ACPI_BUTTON_TYPE_LID) {

drivers/acpi/dock.c

@@ -469,7 +469,7 @@ int dock_notify(struct acpi_device *adev, u32 event)
 		surprise_removal = 1;
 		event = ACPI_NOTIFY_EJECT_REQUEST;
 		/* Fall back */
-		/* fall through */
+		fallthrough;
 	case ACPI_NOTIFY_EJECT_REQUEST:
 		begin_undock(ds);
 		if ((immediate_undock && !(ds->flags & DOCK_IS_ATA))

drivers/acpi/evged.c

@@ -106,7 +106,7 @@ static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares,
 
 		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
 			break;
-		/* fall through */
+		fallthrough;
 	default:
 		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
 			break;

drivers/acpi/processor_idle.c

@@ -203,8 +203,7 @@ static void tsc_check_state(int state)
 		 */
 		if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
 			return;
-
-		/*FALL THROUGH*/
+		fallthrough;
 	default:
 		/* TSC could halt in idle, so notify users */
 		if (state > ACPI_STATE_C1)

drivers/acpi/resource.c

@@ -373,7 +373,7 @@ unsigned int acpi_dev_get_irq_type(int triggering, int polarity)
 	case ACPI_ACTIVE_BOTH:
 		if (triggering == ACPI_EDGE_SENSITIVE)
 			return IRQ_TYPE_EDGE_BOTH;
-		/* fall through */
+		fallthrough;
 	default:
 		return IRQ_TYPE_NONE;
 	}

drivers/acpi/spcr.c

@@ -111,7 +111,7 @@ int __init acpi_parse_spcr(bool enable_earlycon, bool enable_console)
 			table->serial_port.access_width))) {
 		default:
 			pr_err("Unexpected SPCR Access Width.  Defaulting to byte size\n");
-			/* fall through */
+			fallthrough;
 		case 8:
 			iotype = "mmio";
 			break;
@@ -128,7 +128,7 @@ int __init acpi_parse_spcr(bool enable_earlycon, bool enable_console)
 	switch (table->interface_type) {
 	case ACPI_DBG2_ARM_SBSA_32BIT:
 		iotype = "mmio32";
-		/* fall through */
+		fallthrough;
 	case ACPI_DBG2_ARM_PL011:
 	case ACPI_DBG2_ARM_SBSA_GENERIC:
 	case ACPI_DBG2_BCM2835:

drivers/pci/pci-acpi.c

@@ -527,8 +527,8 @@ static void program_hpx_type3_register(struct pci_dev *dev,
 			return;
 
 		break;
-	case HPX_CFG_VEND_CAP:	/* Fall through */
-	case HPX_CFG_DVSEC:	/* Fall through */
+	case HPX_CFG_VEND_CAP:
+	case HPX_CFG_DVSEC:
 	default:
 		pci_warn(dev, "Encountered _HPX type 3 with unsupported config space location");
 		return;
@@ -1001,7 +1001,7 @@ static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 			error = -EBUSY;
 			break;
 		}
-		/* Fall through */
+		fallthrough;
 	case PCI_D0:
 	case PCI_D1:
 	case PCI_D2: