From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Perches <joe@perches.com>
Subject: Re: [PATCH] sfp: allow cotsworks modules
Date: Wed, 28 Mar 2018 03:33:57 -0700
Message-ID: <1522233237.12357.96.camel@perches.com>
References: <E1f189x-00059j-J9@rmk-PC.armlinux.org.uk>
Mime-Version: 1.0
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 7bit
Cc: netdev@vger.kernel.org
To: Russell King <rmk+kernel@armlinux.org.uk>,
        Andrew Lunn <andrew@lunn.ch>,
        Florian Fainelli <f.fainelli@gmail.com>
Return-path: <netdev-owner@vger.kernel.org>
Received: from smtprelay0076.hostedemail.com ([216.40.44.76]:50753 "EHLO
        smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL)
        by vger.kernel.org with ESMTP id S1752106AbeC1KeA (ORCPT
        <rfc822;netdev@vger.kernel.org>); Wed, 28 Mar 2018 06:34:00 -0400
In-Reply-To: <E1f189x-00059j-J9@rmk-PC.armlinux.org.uk>
Sender: netdev-owner@vger.kernel.org
List-ID: <netdev.vger.kernel.org>

On Wed, 2018-03-28 at 11:18 +0100, Russell King wrote:
> Cotsworks modules fail the checksums - it appears that Cotsworks
> reprograms the EEPROM at the end of production with the final product
> information (serial, date code, and exact part number for module
> options) and fails to update the checksum.

trivia:

> diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
[]
> @@ -574,23 +575,43 @@ static int sfp_sm_mod_probe(struct sfp *sfp)
[]
> +		if (cotsworks) {
> +			dev_warn(sfp->dev,
> +				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
> +				 check, id.base.cc_base);
> +		} else {
> +			dev_err(sfp->dev,
> +				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",

It'd be better to move this above the if and
use only a single format string instead of
using 2 slightly different formats.

> +				check, id.base.cc_base);
> +			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
> +				       16, 1, &id, sizeof(id), true);
> +			return -EINVAL;
> +		}
>  	}
>  
>  	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
>  	if (check != id.ext.cc_ext) {
> -		dev_err(sfp->dev,
> -			"EEPROM extended structure checksum failure: 0x%02x\n",
> -			check);
> -		memset(&id.ext, 0, sizeof(id.ext));
> +		if (cotsworks) {
> +			dev_warn(sfp->dev,
> +				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
> +				 check, id.ext.cc_ext);
> +		} else {
> +			dev_err(sfp->dev,
> +				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
> +				check, id.ext.cc_ext);


here too