From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH 1/2] add fixed_phy_update_state() - update state of fixed_phy Date: Fri, 03 Apr 2015 12:25:42 -0700 Message-ID: <551EE936.4010700@gmail.com> References: <551C2AB9.8020508@list.ru> <551C2B37.6000100@list.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: Linux kernel , Stas Sergeev To: Stas Sergeev , netdev@vger.kernel.org Return-path: In-Reply-To: <551C2B37.6000100@list.ru> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 01/04/15 10:30, Stas Sergeev wrote: > > Currently fixed_phy uses a callback to periodically poll the link state. > This patch adds the fixed_phy_update_state() API. > It solves the following problems: > - On link state interrupt, MAC driver can't update status. > Instead it needs to provide the callback to periodically query > the HW about the link state. It is more efficient to update status > after interrupt. > - The callback needs to be unregistered before phy_disconnect(), > or otherwise it will be called with net_dev==NULL. phy_disconnect() > does not have enough info to unregister the callback automatically. > - The callback needs to be registered before of_phy_connect() to > avoid running with outdated state, but of_phy_connect() returns the > phy_device pointer, which is needed to register the callback. Registering > it before of_phy_connect() will therefore require a hack to get the > pointer earlier. > > Overall, this addition makes the subsequent patch that implements > SGMII link status for mvneta, much cleaner. Agreed, now that we have that, we should probably just remove the ability to have a fixed link update callback since it suffers from all the deficiencies you outlined above, and is creating some overhead by polling the hardware. Thanks! -- Florian