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References: <20210816160717.31285-1-arkadiusz.kubalewski@intel.com> <20210816160717.31285-5-arkadiusz.kubalewski@intel.com>
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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Mon, 16 Aug 2021 21:46:41 +0200
Message-ID: <CAK8P3a0N3N3mFvoPj_fkqOY30uudJceox=uwSW+nd0B0kf8-ng@mail.gmail.com>
Subject: Re: [RFC net-next 4/7] net: add ioctl interface for recover reference
 clock on netdev
To:     Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Intel Wired LAN <intel-wired-lan@lists.osuosl.org>,
        Networking <netdev@vger.kernel.org>,
        "open list:KERNEL SELFTEST FRAMEWORK" 
        <linux-kselftest@vger.kernel.org>,
        Jesse Brandeburg <jesse.brandeburg@intel.com>,
        Tony Nguyen <anthony.l.nguyen@intel.com>,
        David Miller <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Richard Cochran <richardcochran@gmail.com>,
        Shuah Khan <shuah@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
        Nikolay Aleksandrov <nikolay@nvidia.com>,
        cong.wang@bytedance.com, Colin Ian King <colin.king@canonical.com>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>
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On Mon, Aug 16, 2021 at 6:18 PM Arkadiusz Kubalewski
<arkadiusz.kubalewski@intel.com> wrote:

> +/*
> + * Structure used for passing data with SIOCSSYNCE and SIOCGSYNCE ioctls
> + */
> +struct synce_ref_clk_cfg {
> +       __u8 pin_id;
> +       _Bool enable;
> +};

I'm not sure if there are any guarantees about the size and alignment of _Bool,
maybe better use __u8 here as well, if only for clarity.

> +#endif /* _NET_SYNCE_H */
> diff --git a/include/uapi/linux/sockios.h b/include/uapi/linux/sockios.h
> index 7d1bccbbef78..32c7d4909c31 100644
> --- a/include/uapi/linux/sockios.h
> +++ b/include/uapi/linux/sockios.h
> @@ -153,6 +153,10 @@
>  #define SIOCSHWTSTAMP  0x89b0          /* set and get config           */
>  #define SIOCGHWTSTAMP  0x89b1          /* get config                   */
>
> +/* synchronous ethernet config per physical function */
> +#define SIOCSSYNCE     0x89c0          /* set and get config           */
> +#define SIOCGSYNCE     0x89c1          /* get config                   */

I understand that these are traditionally using the old-style 16-bit
numbers, but is there any reason to keep doing that rather than
making them modern like this?

#define SIOCSSYNCE     _IOWR(0x89, 0xc0, struct  synce_ref_clk_cfg)
/* set and get config   */
#define SIOCGSYNCE     _IOR(0x89, 0xc1, struct  synce_ref_clk_cfg)
/* get config   */

        Arnd