Re: [PATCH] serial: cpm_uart: use irq variable for platform_get_irq()

[Greg Kroah-Hartman]

On Thu, Oct 01, 2026 at 01:38:15PM -0700, Rosen Penev wrote:
> On Thu Oct 1, 2026 at 1:46 AM PDT, Greg Kroah-Hartman wrote:
> > On Fri, Sep 25, 2026 at 11:15:30AM -0700, Rosen Penev wrote:
> >> struct uart_port has its irq member as an unsigned int, which does not
> >> work when platform_get_irq() returns an error.
> >>
> >> Use a local irq variable to handle this and write to struct uart_port's
> >> irq member when platform_get_irq() succeeds. On success, it returns an
> >> IRQ >= 0, which is representable by unsigned int.
> >>
> >> Fixes: 831603b3e8aa ("serial: cpm_uart: replace irq_of_parse_and_map with platform_get_irq")
> >> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> >> Closes: https://lore.kernel.org/oe-kbuild-all/202609251916.1XlVHLwd-lkp@xxxxxxxxx/
> >> Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
> >> ---
> >>  drivers/tty/serial/cpm_uart.c | 10 ++++++----
> >>  1 file changed, 6 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/drivers/tty/serial/cpm_uart.c b/drivers/tty/serial/cpm_uart.c
> >> index 39f54bb7b485..ca0acccd3dd8 100644
> >> --- a/drivers/tty/serial/cpm_uart.c
> >> +++ b/drivers/tty/serial/cpm_uart.c
> >> @@ -1517,6 +1517,7 @@ static int cpm_uart_probe(struct platform_device *ofdev)
> >>  {
> >>  	int index = probe_index++;
> >>  	struct uart_cpm_port *pinfo = &cpm_uart_ports[index];
> >> +	int irq;
> >>  	int ret;
> >>
> >>  	pinfo->port.line = index;
> >> @@ -1524,14 +1525,15 @@ static int cpm_uart_probe(struct platform_device *ofdev)
> >>  	if (index >= UART_NR)
> >>  		return -ENODEV;
> >>
> >> +	irq = platform_get_irq(ofdev, 0);
> >> +	if (irq < 0)
> >> +		return irq;
> >> +
> >>  	platform_set_drvdata(ofdev, pinfo);
> >>
> >>  	/* initialize the device pointer for the port */
> >>  	pinfo->port.dev = &ofdev->dev;
> >> -
> >> -	pinfo->port.irq = platform_get_irq(ofdev, 0);
> >> -	if (pinfo->port.irq < 0)
> >> -		return pinfo->port.irq;
> >> +	pinfo->port.irq = irq;
> >
> > Why did you move where platform_get_irq() is called?
> 
> So that platform_set_drvdata does not get called on failure.

Why does that matter?