serial: 8250_mtk: Switch to use platform_get_irq()

platform_get_irq() provides an established error code and error message.
Also, it's better to use dedicated API to retrieve Linux IRQ resource.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/20200618122952.88265-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c
index f839380..685ded9 100644 (file)
--- a/drivers/tty/serial/8250/8250_mtk.c
+++ b/drivers/tty/serial/8250/8250_mtk.c
@@ -494,13 +494,17 @@ static int mtk8250_probe_of(struct platform_device *pdev, struct uart_port *p,
 static int mtk8250_probe(struct platform_device *pdev)
 {
        struct uart_8250_port uart = {};
-       struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-       struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
        struct mtk8250_data *data;
-       int err;
+       struct resource *regs;
+       int irq, err;
+
+       irq = platform_get_irq(pdev, 0);
+       if (irq < 0)
+               return irq;
 
-       if (!regs || !irq) {
-               dev_err(&pdev->dev, "no registers/irq defined\n");
+       regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (!regs) {
+               dev_err(&pdev->dev, "no registers defined\n");
                return -EINVAL;
        }
 
@@ -524,7 +528,7 @@ static int mtk8250_probe(struct platform_device *pdev)
 
        spin_lock_init(&uart.port.lock);
        uart.port.mapbase = regs->start;
-       uart.port.irq = irq->start;
+       uart.port.irq = irq;
        uart.port.pm = mtk8250_do_pm;
        uart.port.type = PORT_16550;
        uart.port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT;