RE: [PATCH v2] serial: samsung: Checks the return value of function

From: M Tamseel Shams
Date: Mon Jul 05 2021 - 08:39:29 EST




> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
> Sent: Thursday, July 1, 2021 12:06 PM
> To: Tamseel Shams <m.shams@xxxxxxxxxxx>; gregkh@xxxxxxxxxxxxxxxxxxx;
> jirislaby@xxxxxxxxxx
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-samsung-soc@xxxxxxxxxxxxxxx;
> linux-serial@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> alim.akhtar@xxxxxxxxxxx
> Subject: Re: [PATCH v2] serial: samsung: Checks the return value of function
>
> On 30/06/2021 15:33, Tamseel Shams wrote:
> > "uart_add_one_port" function call may fail and return some error code,
> > so adding a check for return value.
> > If it is returning some error code, then displaying the result,
> > unregistering the driver and then returning from probe function with
> > error code.
> >
> > Signed-off-by: Tamseel Shams <m.shams@xxxxxxxxxxx>
> > ---
> > Changes since v1:
> > 1. Added support to unregister driver on failure of "uart_add_onr_port"
> > function call.
> > 2. Commit message updated.
> >
> > drivers/tty/serial/samsung_tty.c | 11 ++++++++++-
> > 1 file changed, 10 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/tty/serial/samsung_tty.c
> > b/drivers/tty/serial/samsung_tty.c
> > index 9fbc61151c2e..188e2d2da201 100644
> > --- a/drivers/tty/serial/samsung_tty.c
> > +++ b/drivers/tty/serial/samsung_tty.c
> > @@ -2253,7 +2253,11 @@ static int s3c24xx_serial_probe(struct
> platform_device *pdev)
> > }
> >
> > dev_dbg(&pdev->dev, "%s: adding port\n", __func__);
> > - uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
> > + ret = uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
> > + if (ret < 0) {
> > + dev_err(&pdev->dev, "Failed to add uart port, err %d\n", ret);
> > + goto add_port_error;
> > + }
> > platform_set_drvdata(pdev, &ourport->port);
> >
> > /*
> > @@ -2272,6 +2276,11 @@ static int s3c24xx_serial_probe(struct
> platform_device *pdev)
> > probe_index++;
> >
> > return 0;
> > +
> > +add_port_error:
>
> You did not unwind fully s3c24xx_serial_init_port() - clocks.
>
Hi Krzysztof,

Yeah, missed the unwinding of clocks.
Will fix this in next version.

Thanks & Regards,
Tamseel Shams