serial: bcm63xx: Use platform_get_irq() to get the interrupt

platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
allocation of IRQ resources in DT core code, this causes an issue
when using hierarchical interrupt domains using "interrupts" property
in the node as this bypasses the hierarchical setup and messes up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use platform_get_irq().

Acked-by: Florian Fainelli <[email protected]>
Signed-off-by: Lad Prabhakar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: prabhakarlad

drivers/tty/serial/bcm63xx_uart.c

@@ -804,7 +804,7 @@ static struct uart_driver bcm_uart_driver = {
  */
 static int bcm_uart_probe(struct platform_device *pdev)
 {
-	struct resource *res_mem, *res_irq;
+	struct resource *res_mem;
 	struct uart_port *port;
 	struct clk *clk;
 	int ret;
@@ -833,9 +833,10 @@ static int bcm_uart_probe(struct platform_device *pdev)
 	if (IS_ERR(port->membase))
 		return PTR_ERR(port->membase);
 
-	res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	if (!res_irq)
-		return -ENODEV;
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0)
+		return ret;
+	port->irq = ret;
 
 	clk = clk_get(&pdev->dev, "refclk");
 	if (IS_ERR(clk) && pdev->dev.of_node)
@@ -845,7 +846,6 @@ static int bcm_uart_probe(struct platform_device *pdev)
 		return -ENODEV;
 
 	port->iotype = UPIO_MEM;
-	port->irq = res_irq->start;
 	port->ops = &bcm_uart_ops;
 	port->flags = UPF_BOOT_AUTOCONF;
 	port->dev = &pdev->dev;