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Date:   Thu, 19 Sep 2019 18:34:29 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Jerome Pouiller <Jerome.Pouiller@silabs.com>
Cc:     "devel@driverdev.osuosl.org" <devel@driverdev.osuosl.org>,
        "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Kalle Valo <kvalo@codeaurora.org>,
        "David S . Miller" <davem@davemloft.net>,
        David Le Goff <David.Legoff@silabs.com>
Subject: Re: [PATCH 02/20] staging: wfx: add support for I/O access
Message-ID: <20190919163429.GB27277@lunn.ch>
References: <20190919105153.15285-1-Jerome.Pouiller@silabs.com>
 <20190919105153.15285-3-Jerome.Pouiller@silabs.com>
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On Thu, Sep 19, 2019 at 10:52:35AM +0000, Jerome Pouiller wrote:
> +static int wfx_sdio_copy_from_io(void *priv, unsigned int reg_id,
> +				 void *dst, size_t count)
> +{
> +	struct wfx_sdio_priv *bus = priv;
> +	unsigned int sdio_addr = reg_id << 2;
> +	int ret;
> +
> +	BUG_ON(reg_id > 7);

Hi Jerome

BUG_ON should only be used when the system is corrupted, and there is
no alternative than to stop the machine, so it does not further
corrupt itself. Accessing a register which does not exist is not a
reason the kill the machine. A WARN() and a return of -EINVAL would be
better.

	Andrew