From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B752A1FC7FB; Tue, 5 May 2026 12:30:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777984240; cv=none; b=vAv3eIeoXixCC2qj2wTEr+0NOcmEIas49wZX5DvqFBwqQP92jyd409BR1q1znbq5Idu8QBJbzWtzKAKPdc+t2QfnXzqIeEwnL1GsaeB/ppcvVjUUGs7jeUre4eE4zHhcKde1cbWb+dfxGxidve7MhqiSRAS8ZSxrOzJjEDdQJLw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777984240; c=relaxed/simple; bh=mlmz7svxF9IDn/hnRBASBa2pHooKa2riBc5sLpBSw3o=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Nn89nbMAeqq+7wy2WaKz0kLd3yRnFvGfvQ+im73LL1b17yXyW6uoJgcOlZR6FmNwn7BOTz2etNtTLukFp563NSjwHtPm9E3bPWkT2w2YTjVPA/frY/QLzakXEKaUfYRADTUdUbwPrlGt6mBJrzWR1Y9rgvSPPU5/O1GPJTqoqbw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=FSvmC5k8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="FSvmC5k8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B2C7C2BCB4; Tue, 5 May 2026 12:30:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777984240; bh=mlmz7svxF9IDn/hnRBASBa2pHooKa2riBc5sLpBSw3o=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=FSvmC5k8fRgz0k4CKA+gZLUA1Gr4hDbQopEcSaJsYdaLPBOKbA06F8Ahg4yZ8ur9R Bdkg4ba94KDwnHkjrk/1yOr2rtvaPeSZbAtdcC6tEqD17LSRrbGW/b+NEjmxQnSBRn KfiAiBf3RI119i0eNQKwdRRwL48bimRxdE6B9XNtvaSkKPka4Mdd22ZpySO180Uzlv 9RKdbbrFSkmA9N3BDzXrp6YOa7C7sbjP9Vbwwy7DXsGIW/iHaAfr+S2iZo+C/qB+Ba +wXf/qoJk5lGhh4IWRvSqlNpM+4jlcxVmoUQ8bTLepAc4Z3BmDZRaTH3Budo9f49xd KdFoFCQDw3Jpg== Message-ID: Date: Tue, 5 May 2026 14:30:36 +0200 Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] media: i2c: upd64031a: add error handling for I2C read To: Wenyuan Li <2063309626@qq.com>, Mauro Carvalho Chehab Cc: Hans Verkuil , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, gszhai@bjtu.edu.cn, 25125332@bjtu.edu.cn, 25125283@bjtu.edu.cn, 23120469@bjtu.edu.cn References: From: Hans Verkuil Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/31/26 15:20, Wenyuan Li wrote: > In upd64031a_read(), i2c_master_recv() is called without checking > its return value. If the I2C read fails, the function proceeds to > return invalid data from the buffer. > > Add proper error checking: > - Check if all 2 bytes were read successfully > - Log the error with %pe format > - Return 0xff (the same as invalid register) on error I'm not picking this up: it's not worth the effort, and this read is used for debugging only. Failures won't hurt anything. Ditto for your upd64083 patch. Regards, Hans > > Signed-off-by: Wenyuan Li <2063309626@qq.com> > --- > drivers/media/i2c/upd64031a.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/drivers/media/i2c/upd64031a.c b/drivers/media/i2c/upd64031a.c > index a178af46e695..ec9179cf9b69 100644 > --- a/drivers/media/i2c/upd64031a.c > +++ b/drivers/media/i2c/upd64031a.c > @@ -73,10 +73,19 @@ static u8 upd64031a_read(struct v4l2_subdev *sd, u8 reg) > { > struct i2c_client *client = v4l2_get_subdevdata(sd); > u8 buf[2]; > + int ret; > > if (reg >= sizeof(buf)) > return 0xff; > - i2c_master_recv(client, buf, 2); > + > + ret = i2c_master_recv(client, buf, 2); > + if (ret != sizeof(buf)) { > + int err = ret < 0 ? ret : -EIO; > + > + v4l2_err(sd, "I2C read failed: %pe\n", ERR_PTR(err)); > + return 0xff; > + } > + > return buf[reg]; > } >