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Date:   Thu, 12 Dec 2019 15:46:27 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Vitor Soares <Vitor.Soares@synopsys.com>
Cc:     linux-kernel@vger.kernel.org, linux-i3c@lists.infradead.org,
        Joao.Pinto@synopsys.com, bbrezillon@kernel.org, wsa@the-dreams.de,
        arnd@arndb.de, broonie@kernel.org
Subject: Re: [RFC 5/5] i3c: add i3cdev module to expose i3c dev in /dev
Message-ID: <20191212144627.GC1668196@kroah.com>
References: <cover.1575977795.git.vitor.soares@synopsys.com>
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On Tue, Dec 10, 2019 at 04:37:33PM +0100, Vitor Soares wrote:
> +static struct i3cdev_data *i3cdev_get_by_minor(unsigned int minor)

Why?  Why not just embed the structure in the cdev if you really need
it?

> +static struct i3cdev_data *get_free_i3cdev(struct i3c_device *i3c)
> +{
> +	struct i3cdev_data *i3cdev;
> +	unsigned long minor;
> +
> +	minor = find_first_zero_bit(minors, N_I3C_MINORS);

No locking, fun!!!

:(

Why not use an idr instead, that is what it is there for.  Don't try to
roll your own.

thanks,

greg k-h