genirq/chip: Rework irq_set_msi_desc_off()

Use the new guards to get and lock the interrupt descriptor and tidy up the
code.

Fixup the kernel doc comment while at it.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/20250429065421.473563978@linutronix.de

Author: KAGA-KOKO

kernel/irq/chip.c

@@ -84,34 +84,30 @@ int irq_set_handler_data(unsigned int irq, void *data)
 EXPORT_SYMBOL(irq_set_handler_data);
 
 /**
- *	irq_set_msi_desc_off - set MSI descriptor data for an irq at offset
- *	@irq_base:	Interrupt number base
- *	@irq_offset:	Interrupt number offset
- *	@entry:		Pointer to MSI descriptor data
+ * irq_set_msi_desc_off - set MSI descriptor data for an irq at offset
+ * @irq_base:	Interrupt number base
+ * @irq_offset:	Interrupt number offset
+ * @entry:		Pointer to MSI descriptor data
  *
- *	Set the MSI descriptor entry for an irq at offset
+ * Set the MSI descriptor entry for an irq at offset
  */
-int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
-			 struct msi_desc *entry)
+int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset, struct msi_desc *entry)
 {
-	unsigned long flags;
-	struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
-
-	if (!desc)
-		return -EINVAL;
-	desc->irq_common_data.msi_desc = entry;
-	if (entry && !irq_offset)
-		entry->irq = irq_base;
-	irq_put_desc_unlock(desc, flags);
-	return 0;
+	scoped_irqdesc_get_and_lock(irq_base + irq_offset, IRQ_GET_DESC_CHECK_GLOBAL) {
+		scoped_irqdesc->irq_common_data.msi_desc = entry;
+		if (entry && !irq_offset)
+			entry->irq = irq_base;
+		return 0;
+	}
+	return -EINVAL;
 }
 
 /**
- *	irq_set_msi_desc - set MSI descriptor data for an irq
- *	@irq:	Interrupt number
- *	@entry:	Pointer to MSI descriptor data
+ * irq_set_msi_desc - set MSI descriptor data for an irq
+ * @irq:	Interrupt number
+ * @entry:	Pointer to MSI descriptor data
  *
- *	Set the MSI descriptor entry for an irq
+ * Set the MSI descriptor entry for an irq
  */
 int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
 {