From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kishon Vijay Abraham I Subject: Re: [RFC PATCH 01/11] phy: core add phy_set_netif_mode() api Date: Thu, 25 Oct 2018 15:35:46 +0530 Message-ID: References: <20181008234949.15416-1-grygorii.strashko@ti.com> <20181008234949.15416-2-grygorii.strashko@ti.com> <54ba13bb-95e1-1519-a30f-8da198447489@ti.com> <18219d97-f86e-27ee-a116-a8febc3dcd24@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Sekhar Nori , , , To: Grygorii Strashko , "David S. Miller" , , Tony Lindgren , Rob Herring Return-path: Received: from lelv0143.ext.ti.com ([198.47.23.248]:43898 "EHLO lelv0143.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726852AbeJYSi3 (ORCPT ); Thu, 25 Oct 2018 14:38:29 -0400 In-Reply-To: <18219d97-f86e-27ee-a116-a8febc3dcd24@ti.com> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: Hi, On Wednesday 10 October 2018 04:13 AM, Grygorii Strashko wrote: > > > On 10/09/2018 12:22 AM, Kishon Vijay Abraham I wrote: >> Hi Grygorii, >> >> On Tuesday 09 October 2018 05:19 AM, Grygorii Strashko wrote: >>> Add new API phy_set_netif_mode(struct phy *phy, phy_interface_t mode) and >>> new PHY operation callback .set_netif_mode() which intended to be implemnte >>> by PHY drivers which supports Network interrfaces mode selection. Both >>> accepts phy_interface_t vlaue as input parameter. >>> >>> Cc: Kishon Vijay Abraham I >>> Cc: Tony Lindgren >>> Signed-off-by: Grygorii Strashko >>> --- >>> drivers/phy/phy-core.c | 15 +++++++++++++++ >>> include/linux/phy/phy.h | 12 ++++++++++++ >>> 2 files changed, 27 insertions(+) >>> >>> diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c >>> index 35fd38c..d9aba1a 100644 >>> --- a/drivers/phy/phy-core.c >>> +++ b/drivers/phy/phy-core.c >>> @@ -377,6 +377,21 @@ int phy_set_mode(struct phy *phy, enum phy_mode mode) >>> } >>> EXPORT_SYMBOL_GPL(phy_set_mode); >>> >>> +int phy_set_netif_mode(struct phy *phy, phy_interface_t mode) >>> +{ >>> + int ret; >>> + >>> + if (!phy || !phy->ops->set_netif_mode) >>> + return 0; >>> + >>> + mutex_lock(&phy->mutex); >>> + ret = phy->ops->set_netif_mode(phy, mode); >>> + mutex_unlock(&phy->mutex); >>> + >>> + return ret; >>> +} >>> +EXPORT_SYMBOL_GPL(phy_set_netif_mode); >> >> We should try to add only generic PHY APIs and not subsystem specific APIs. In >> this case I think phy_set_mode should suffice. > > > This is what I've had in mind first, but all my guts argued against it after I've tried: > > diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h > index bc73d2b..961b156 100644 > --- a/include/linux/phy/phy.h > +++ b/include/linux/phy/phy.h > @@ -41,6 +41,14 @@ enum phy_mode { > PHY_MODE_10GKR, > PHY_MODE_UFS_HS_A, > PHY_MODE_UFS_HS_B, > + PHY_MODE_MODE_MII, > + PHY_MODE_MODE_GMII, > + PHY_MODE_MODE_SGMII, > + PHY_MODE_MODE_RMII, > + PHY_MODE_MODE_RGMII, > + PHY_MODE_MODE_RGMII_ID, > + PHY_MODE_MODE_RGMII_RXID, > + PHY_MODE_MODE_RGMII_TXID, > }; > > above introduces ugly constants duplication and required every network phy driver > to maintain conversation table phy_interface_t -> enum phy_mode. > More over, if above change happens third time (first time PHY_MODE_SGMII/PHY_MODE_10GKR were added, > second - PHY_MODE_2500SGMII) it will never ends (there are ~15 more items only in phy_interface_t). > As result, enum phy_mode might became a un-maintainable monster. > > So, as per above, and considering that Network subsystem is based on standards (phy_interface_t lists standard intf) > I've tried to add separate PHY API. > > As an idea: > - seems it could be reasonable to introduce PHY_MODE_NETWORK (or PHY_MODE_ETHERNET) and > add generic phy_set_submode(struct phy *phy, long submode). > > So, single functional PHY device can just use phy_set_submode() and > multi-functional devices (like serdes which can be muxed between PCIe, USB, NET), can use: > > phy_set_mode(PHY_MODE_ETHERNET) > phy_set_submode(X); Agreed on the constant duplication comment above. We can modify set_mode to take submode as an additional parameter and fix all the users of phy_set_mode. int phy_set_mode(struct phy *phy, enum phy_mode mode, int submode) Thanks Kishon