Re: [PATCH] nfc: port100: fix using -ERRNO as command type mask

[Krzysztof Kozlowski]

On 25/10/2021 16:47, Krzysztof Kozlowski wrote:
> During probing, the driver tries to get a list (mask) of supported
> command types in port100_get_command_type_mask() function.  The value
> is u64 and 0 is treated as invalid mask (no commands supported).  The
> function however returns also -ERRNO as u64 which will be interpret as
> valid command mask.
> 
> Return 0 on every error case of port100_get_command_type_mask(), so the
> probing will stop.
> 
> Cc: <stable@xxxxxxxxxxxxxxx>
> Fixes: 0347a6ab300a ("NFC: port100: Commands mechanism implementation")
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
> ---
>  drivers/nfc/port100.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/nfc/port100.c b/drivers/nfc/port100.c
> index 1296148b4566..ec1630bfedf4 100644
> --- a/drivers/nfc/port100.c
> +++ b/drivers/nfc/port100.c
> @@ -1109,15 +1109,11 @@ static u64 port100_get_command_type_mask(struct port100 *dev)
>  
>  	skb = port100_alloc_skb(dev, 0);
>  	if (!skb)
> -		return -ENOMEM;
> +		return 0;
>  
> -	nfc_err(&dev->interface->dev, "%s:%d\n", __func__, __LINE__);

Mistake, please ignore.

Best regards,
Krzysztof