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

[ Upstream commit 5b68061 ]

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().

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20211224142917.6966-5-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 2a1d728 ("tty: serial: meson: fix hard LOCKUP on crtscts mode")
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: prabhakarlad

drivers/tty/serial/meson_uart.c

@@ -665,10 +665,11 @@ static int meson_uart_probe_clocks(struct platform_device *pdev,
 
 static int meson_uart_probe(struct platform_device *pdev)
 {
-	struct resource *res_mem, *res_irq;
+	struct resource *res_mem;
 	struct uart_port *port;
 	u32 fifosize = 64; /* Default is 64, 128 for EE UART_0 */
 	int ret = 0;
+	int irq;
 
 	if (pdev->dev.of_node)
 		pdev->id = of_alias_get_id(pdev->dev.of_node, "serial");
@@ -691,9 +692,9 @@ static int meson_uart_probe(struct platform_device *pdev)
 	if (!res_mem)
 		return -ENODEV;
 
-	res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	if (!res_irq)
-		return -ENODEV;
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
 
 	of_property_read_u32(pdev->dev.of_node, "fifo-size", &fifosize);
 
@@ -718,7 +719,7 @@ static int meson_uart_probe(struct platform_device *pdev)
 	port->iotype = UPIO_MEM;
 	port->mapbase = res_mem->start;
 	port->mapsize = resource_size(res_mem);
-	port->irq = res_irq->start;
+	port->irq = irq;
 	port->flags = UPF_BOOT_AUTOCONF | UPF_LOW_LATENCY;
 	port->dev = &pdev->dev;
 	port->line = pdev->id;