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Message-ID: <99e3ad4f-077a-0ca0-6842-b0c5a3439b68@linaro.org>
Date:   Sun, 26 Jun 2022 21:49:28 +0200
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Subject: Re: [PATCH 1/2] NFC: nxp-nci: check return code of i2c_master_recv()
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To:     Michael Walle <michael@walle.cc>,
        Charles Gorand <charles.gorand@effinnov.com>
Cc:     =?UTF-8?Q?Cl=c3=a9ment_Perrochaud?= <clement.perrochaud@nxp.com>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20220626194243.4059870-1-michael@walle.cc>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20220626194243.4059870-1-michael@walle.cc>
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On 26/06/2022 21:42, Michael Walle wrote:
> Check the return code of i2c_master_recv() for actual errors and
> propagate it to the caller.
> 
> Fixes: 6be88670fc59 ("NFC: nxp-nci_i2c: Add I2C support to NXP NCI driver")

The check was there, so I don't see here bug. The only thing missing was
a bit more detailed error message (without cast to %u) and propagating
error code instead of EBADMSG, but these are not bugs. The commit msg
should sound different and Fixes tag is not appropriate.

> Signed-off-by: Michael Walle <michael@walle.cc>
> ---
>  drivers/nfc/nxp-nci/i2c.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/nfc/nxp-nci/i2c.c b/drivers/nfc/nxp-nci/i2c.c
> index 7e451c10985d..9c80d5a6d56b 100644
> --- a/drivers/nfc/nxp-nci/i2c.c
> +++ b/drivers/nfc/nxp-nci/i2c.c
> @@ -163,7 +163,10 @@ static int nxp_nci_i2c_nci_read(struct nxp_nci_i2c_phy *phy,
>  	skb_put_data(*skb, (void *)&header, NCI_CTRL_HDR_SIZE);
>  
>  	r = i2c_master_recv(client, skb_put(*skb, header.plen), header.plen);
> -	if (r != header.plen) {
> +	if (r < 0) {
> +		nfc_err(&client->dev, "I2C receive error %pe\n", ERR_PTR(r));

Print just 'r'.

> +		goto nci_read_exit_free_skb;
> +	} else if (r != header.plen) {
>  		nfc_err(&client->dev,
>  			"Invalid frame payload length: %u (expected %u)\n",
>  			r, header.plen);


Best regards,
Krzysztof