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Date:   Mon, 20 Sep 2021 12:14:24 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Min Li <min.li.xe@renesas.com>
Cc:     "richardcochran@gmail.com" <richardcochran@gmail.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "andrew@lunn.ch" <andrew@lunn.ch>
Subject: Re: [PATCH net v2 2/2] ptp: idt82p33: implement double dco time
 correction
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On Mon, 20 Sep 2021 14:08:37 +0000 Min Li wrote:
> > > We use this parameter to specify firmware so that module can be
> > > autoloaded /etc/modprobe.d/modname.conf  
> > 
> > Sorry, I don't understand. The firmware is in /lib/firmware.
> > Previously you used a card coded name (whatever FW_FILENAME is,
> > "idt82p33xxx.bin"?). This patch adds the ability to change the firmware file
> > name by a module param.
> > 
> > Now let me repeat the question - what's the point of user changing the
> > requested firmware name if they can simply rename the file?  
> 
> We have different firmware named after different 1588 profiles. If we
> rename firmware, it would make every profile  look same and
> confusing.

You can use symlinks to "choose" which FW will be loaded by the kernel:

ls -sn $real_fw_filename $FW_FILENAME

> On the other hand, with this module parameter, we can have
> phc module auto start with correct firmware.