Re: [PATCH v2] serial/8250_dw: use platform_get_irq() instead of platform_get_resource()

From: Andy Shevchenko
Date: Tue Mar 03 2015 - 10:26:11 EST


On Tue, 2015-03-03 at 18:11 +0300, Alexey Brodkin wrote:
> It is not recommened to use platform_get_resource(pdev, IORESOURCE_IRQ)
> for requesting IRQ's resources any more, as they can be not ready yet in
> case of DT-booting.
>
> platform_get_irq() instead is a recommended way for getting IRQ even if
> it was not retrieved earlier.
>
> It also makes code simpler because we're getting "int" value right away
> and no conversion from resource to int is required.
>
> Signed-off-by: Alexey Brodkin <abrodkin@xxxxxxxxxxxx>
> Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx>
> Cc: Alan Cox <alan@xxxxxxxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
>
> Changes in v2:
> * Suppress error message if platform_get_irq() returns -EPROBE_DEFER

Do we really need that message at all?

>
> ---
> drivers/tty/serial/8250/8250_dw.c | 14 ++++++++++----
> 1 file changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
> index e601162..cda76e8 100644
> --- a/drivers/tty/serial/8250/8250_dw.c
> +++ b/drivers/tty/serial/8250/8250_dw.c
> @@ -384,18 +384,24 @@ static int dw8250_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);
> + int irq = platform_get_irq(pdev, 0);
> struct dw8250_data *data;
> int err;
>
> - if (!regs || !irq) {
> - dev_err(&pdev->dev, "no registers/irq defined\n");
> + if (!regs) {
> + dev_err(&pdev->dev, "no registers defined\n");
> return -EINVAL;
> }
>
> + if (irq < 0) {
> + if (irq != -EPROBE_DEFER)
> + dev_err(&pdev->dev, "cannot get irq\n");
> + return irq;
> + }
> +
> spin_lock_init(&uart.port.lock);
> uart.port.mapbase = regs->start;
> - uart.port.irq = irq->start;
> + uart.port.irq = irq;
> uart.port.handle_irq = dw8250_handle_irq;
> uart.port.pm = dw8250_do_pm;
> uart.port.type = PORT_8250;


--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>
Intel Finland Oy

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