From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH net-next 4/9] net: dsa: Allow configuration of CPU & DSA port speeds/duplex Date: Mon, 24 Aug 2015 10:41:25 -0700 Message-ID: <55DB5745.6010605@gmail.com> References: <1440323220-20438-1-git-send-email-andrew@lunn.ch> <1440323220-20438-5-git-send-email-andrew@lunn.ch> <55DA1340.9080604@gmail.com> <20150823212404.GD20710@lunn.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: David Miller , netdev To: Andrew Lunn Return-path: Received: from mail-pa0-f48.google.com ([209.85.220.48]:33685 "EHLO mail-pa0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751179AbbHXRny (ORCPT ); Mon, 24 Aug 2015 13:43:54 -0400 Received: by pacti10 with SMTP id ti10so28808975pac.0 for ; Mon, 24 Aug 2015 10:43:54 -0700 (PDT) In-Reply-To: <20150823212404.GD20710@lunn.ch> Sender: netdev-owner@vger.kernel.org List-ID: On 23/08/15 14:24, Andrew Lunn wrote: >>> + port_dn = cd->port_dn[port]; >>> + if (of_phy_is_fixed_link(port_dn)) { >>> + ret = of_phy_register_fixed_link(port_dn); >>> + if (ret) { >>> + netdev_err(master, >>> + "failed to register fixed PHY\n"); >>> + return ret; >>> + } >>> + phydev = of_phy_find_device(port_dn); >>> + genphy_config_init(phydev); >>> + genphy_read_status(phydev); >>> + if (ds->drv->adjust_link) >>> + ds->drv->adjust_link(ds, port, phydev); >> >> This kind of hack here because what you really need is just the link >> parameters, but you cannot obtain such information without first >> configuring the PHY up to a certain point in genphy_config_init(), and >> then have genphy_read_status() copy these values in your phydev structure. >> >> Maybe we should really consider something like this after all: >> >> https://lkml.org/lkml/2015/8/5/490 > > Hi Florian > > This half solves the problem. The nice thing about using the > fixed_link, is that i can just call the adjust_link function with it. > The fixed_phy_status cannot be passed directly to adjust_link. Some > code refactoring or duplication would be needed. Right, and using an adjust_link callback seems a little cleaner anyway since you get an abstracted PHY device to work with. > >> Or maybe, we should really introduce this "cpu" network device after all >> with a dropping xmit function, such that we get ethtool counters to work >> on it, and we can also attach it to a PHY device to configure link >> parameters? > > I keep humming and harring about this. I don't really like the idea of > having an interface which you cannot send/receive packets. Yet it > solves a number of problems like this, and gives you access to > statistics and registers in the usual way. Right that would be my primary motivation and use case as well. > If we do it for the CPU > port, we should also do it for the DSA ports. And we probably want the > call for up to return -ENOSUP, just to make it clear it cannot be used > for anything. We should definitively start a separate thread for this, as there might be real uses cases that are not yet covered that would need a network device. Let's go ahead with your patch for now: Reviewed-by: Florian Fainelli -- Florian