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Date:   Fri, 28 Sep 2018 17:17:50 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     "Y.b. Lu" <yangbo.lu@nxp.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "devel@driverdev.osuosl.org" <devel@driverdev.osuosl.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        Richard Cochran <richardcochran@gmail.com>,
        "David S . Miller" <davem@davemloft.net>,
        Ioana Ciocoi Radulescu <ruxandra.radulescu@nxp.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: Re: [PATCH 1/2] net: dpaa2: move DPAA2 PTP driver out of staging/
Message-ID: <20180928151750.GD19396@lunn.ch>
References: <20180927111228.46118-1-yangbo.lu@nxp.com>
 <20180927132507.GB23375@lunn.ch>
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> > struct dprtc_cmd_get_irq - Putting pad at the beginning of a struct seems very
> > odd. And it is not the only example.
> 
> [Y.b. Lu] This should depended on MC firmware and APIs I think. Once the MC improves this, the APIs could be updated to fix this.

That is going to be hard to do. Ideally the driver should work with
any firmware version. You don't really want to force the user to
upgrade the driver/kernel and the firmware at the same time. So you
cannot for example remove this pad. What you might be able to do in
newer versions is actually use the space. But you have to be sure the
current code is correctly ignoring it and setting it to zero.

	Andrew