[PATCH v3] serial: samsung: Re-factors UART IRQ resource for various Samsung SoC

[M Tamseel Shams]

> > In few older Samsung SoCs like s3c2410, s3c2412 and s3c2440, UART IP
> > is having 2 interrupt lines.
> > However, in other SoCs like s3c6400, s5pv210, exynos5433, and
> > exynos4210 UART is having only 1 interrupt line. Due to this,
> > "platform_get_irq(platdev, 1)"
> > call in the driver gives the following warning:
> > "IRQ index 1 not found" on recent platforms.
> >
> > This patch re-factors the IRQ resources handling for each platform and
> > hence fixing the above warnings seen on some platforms.
> >
> > Signed-off-by: Tamseel Shams <m.shams at samsung.com>
> > ---
> > Removed the logic of irq_cnt and directly using
> > s3c24xx_serial_has_interrupt_mask() to check for number of interrupt
> > lines.
> >
> >  drivers/tty/serial/samsung_tty.c | 7 +++++--
> >  1 file changed, 5 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/tty/serial/samsung_tty.c
> > b/drivers/tty/serial/samsung_tty.c
> > index 6ef614d8648c..8a955f3d8975 100644
> > --- a/drivers/tty/serial/samsung_tty.c
> > +++ b/drivers/tty/serial/samsung_tty.c
> > @@ -1908,10 +1908,13 @@ static int s3c24xx_serial_init_port(struct
> s3c24xx_uart_port *ourport,
> >  	else {
> >  		port->irq = ret;
> >  		ourport->rx_irq = ret;
> > -		ourport->tx_irq = ret + 1;
> > +		if (s3c24xx_serial_has_interrupt_mask(port))
> > +			ourport->tx_irq = ret;
> 
> Hi,
> 
> I don't understand: Why do you assign here the same interrupt as RX?
> 
> Best regards,
> Krzysztof
> 
Hi Krzysztof,
I was assigning the same interrupt to Tx and Rx for UART, which have one interrupt line, 
but ourport->tx_irq is never used for those UART's. So, leaving it as it was.
The change now is using platform_get_irq_optional () instead of platform_get_irq ()
to avoid false-positive error.

Thanks & Regards,
Tamseel