Re: [PATCH v3 2/9] ptp: Add generic ptp message type function

[Richard Cochran <richardcochran@gmail.com>]

On Thu, Jul 30, 2020 at 10:00:41AM +0200, Kurt Kanzenbach wrote:
> The message type is located at different offsets within the ptp header depending
> on the ptp version (v1 or v2). Therefore, drivers which also deal with ptp v1
> have some code for it.
> 
> Extract this into a helper function for drivers to be used.
> 
> Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>

Reviewed-by: Richard Cochran <richardcochran@gmail.com>

CodingStyle nit below...

> ---
>  include/linux/ptp_classify.h | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/include/linux/ptp_classify.h b/include/linux/ptp_classify.h
> index 26fd38a4bd67..f4dd42fddc0c 100644
> --- a/include/linux/ptp_classify.h
> +++ b/include/linux/ptp_classify.h
> @@ -90,6 +90,30 @@ unsigned int ptp_classify_raw(const struct sk_buff *skb);
>   */
>  struct ptp_header *ptp_parse_header(struct sk_buff *skb, unsigned int type);
>  
> +/**
> + * ptp_get_msgtype - Extract ptp message type from given header
> + * @hdr: ptp header
> + * @type: type of the packet (see ptp_classify_raw())
> + *
> + * This function returns the message type for a given ptp header. It takes care
> + * of the different ptp header versions (v1 or v2).
> + *
> + * Return: The message type
> + */
> +static inline u8 ptp_get_msgtype(const struct ptp_header *hdr,
> +				 unsigned int type)
> +{
> +	u8 msgtype;
> +
> +	if (unlikely(type & PTP_CLASS_V1))
> +		/* msg type is located at the control field for ptp v1 */
> +		msgtype = hdr->control;

With the comment, it looks like two statements, and so please use 

	if (...) {
		/**/
		...
	} else {
		...
	}

here.

> +	else
> +		msgtype = hdr->tsmt & 0x0f;
> +
> +	return msgtype;
> +}
> +
>  void __init ptp_classifier_init(void);
>  #else
>  static inline void ptp_classifier_init(void)
> -- 
> 2.20.1
>