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

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

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@synopsys.com>
> Cc: Vineet Gupta <vgupta@synopsys.com>
> Cc: Alan Cox <alan@linux.intel.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> 
>  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@intel.com>
Intel Finland Oy