From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756190AbaFYIow (ORCPT ); Wed, 25 Jun 2014 04:44:52 -0400 Received: from mail-qg0-f53.google.com ([209.85.192.53]:48666 "EHLO mail-qg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754563AbaFYIon (ORCPT ); Wed, 25 Jun 2014 04:44:43 -0400 MIME-Version: 1.0 In-Reply-To: <53A9FCDB.6060805@cogentembedded.com> References: <1402056736-12674-1-git-send-email-gautam.vivek@samsung.com> <1402056736-12674-3-git-send-email-gautam.vivek@samsung.com> <53A9FCDB.6060805@cogentembedded.com> Date: Wed, 25 Jun 2014 14:14:42 +0530 X-Google-Sender-Auth: Z0zTG5nVXN_roWrPSJbiPQXmuW8 Message-ID: Subject: Re: [PATCH 2/4] usb: host: xhci-plat: Add support to get PHYs From: Vivek Gautam To: Sergei Shtylyov Cc: Julius Werner , "linux-usb@vger.kernel.org" , "linux-samsung-soc@vger.kernel.org" , Greg Kroah-Hartman , kishon , Mathias Nyman , LKML , "linux-arm-kernel@lists.infradead.org" , Kukjin Kim Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Wed, Jun 25, 2014 at 4:04 AM, Sergei Shtylyov wrote: > Hello. > > > On 06/10/2014 12:22 AM, Julius Werner wrote: > >>> diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h >>> index 9ffecd5..453d89e 100644 >>> --- a/drivers/usb/host/xhci.h >>> +++ b/drivers/usb/host/xhci.h >>> @@ -1582,6 +1582,9 @@ struct xhci_hcd { >>> u32 port_status_u0; >>> /* Compliance Mode Timer Triggered every 2 seconds */ >>> #define COMP_MODE_RCVRY_MSECS 2000 >>> + /* phys for the controller */ >>> + struct phy *phy2_gen; >>> + struct phy *phy3_gen; >>> }; > > >> I don't think adding new variables here and restricting most of this >> logic to xhci-plat.c (in the next patch) is the best way to do it. > > > Indeed. > > >> There's no conceptual reason why other host controllers (e.g. xhci-pci >> or even EHCI) could not have a similar need to tune their PHY after >> reset. PHYs are universal to all host controllers. > > >> There is already a 'phy' member in struct usb_hcd which I think is >> mostly unused right now. I think it would be much less >> confusing/redundant to reuse that member for this purpose (you could >> still set it up from xhci_plat_probe(), and then call it from >> hcd_bus_resume() or something like that). > > > That member has type 'struct usb_phy *' while here we have 'struct phy *' > -- feel the difference. > I have already tried adding 'struct phy *gen_phy' to 'struct usb_hcd', So the 'struct phy *' available in the usb_hcd is requested in usb_add_hcd(). This is requested with the constant string 'usb' : struct phy *phy = phy_get(hcd->self.controller, "usb"); This can get the phy with string 'usb' only if, either the host controller has a device node wherein the phys are given. Even in this case one can't give same constant string for two different phys, UTMI+ and PIPE3 phy, isn't it ? Or, the other way can be when host gets a lookup table to look into to find the relevant phys, something like Heikki has suggested: usb: dwc3: host: convey the PHYs to xhci (https://lkml.org/lkml/2014/6/5/585) and related patch series. So if we use this second approach, we would need to override the 'phy_get()' that has been done in usb_add_hcd() in xhci_plat_probe(), and then use them in later operations. am i getting the things correctly ? -- Best Regards Vivek Gautam Samsung R&D Institute, Bangalore India From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vivek Gautam Subject: Re: [PATCH 2/4] usb: host: xhci-plat: Add support to get PHYs Date: Wed, 25 Jun 2014 14:14:42 +0530 Message-ID: References: <1402056736-12674-1-git-send-email-gautam.vivek@samsung.com> <1402056736-12674-3-git-send-email-gautam.vivek@samsung.com> <53A9FCDB.6060805@cogentembedded.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <53A9FCDB.6060805@cogentembedded.com> Sender: linux-kernel-owner@vger.kernel.org To: Sergei Shtylyov Cc: Julius Werner , "linux-usb@vger.kernel.org" , "linux-samsung-soc@vger.kernel.org" , Greg Kroah-Hartman , kishon , Mathias Nyman , LKML , "linux-arm-kernel@lists.infradead.org" , Kukjin Kim List-Id: linux-samsung-soc@vger.kernel.org Hi, On Wed, Jun 25, 2014 at 4:04 AM, Sergei Shtylyov wrote: > Hello. > > > On 06/10/2014 12:22 AM, Julius Werner wrote: > >>> diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h >>> index 9ffecd5..453d89e 100644 >>> --- a/drivers/usb/host/xhci.h >>> +++ b/drivers/usb/host/xhci.h >>> @@ -1582,6 +1582,9 @@ struct xhci_hcd { >>> u32 port_status_u0; >>> /* Compliance Mode Timer Triggered every 2 seconds */ >>> #define COMP_MODE_RCVRY_MSECS 2000 >>> + /* phys for the controller */ >>> + struct phy *phy2_gen; >>> + struct phy *phy3_gen; >>> }; > > >> I don't think adding new variables here and restricting most of this >> logic to xhci-plat.c (in the next patch) is the best way to do it. > > > Indeed. > > >> There's no conceptual reason why other host controllers (e.g. xhci-pci >> or even EHCI) could not have a similar need to tune their PHY after >> reset. PHYs are universal to all host controllers. > > >> There is already a 'phy' member in struct usb_hcd which I think is >> mostly unused right now. I think it would be much less >> confusing/redundant to reuse that member for this purpose (you could >> still set it up from xhci_plat_probe(), and then call it from >> hcd_bus_resume() or something like that). > > > That member has type 'struct usb_phy *' while here we have 'struct phy *' > -- feel the difference. > I have already tried adding 'struct phy *gen_phy' to 'struct usb_hcd', So the 'struct phy *' available in the usb_hcd is requested in usb_add_hcd(). This is requested with the constant string 'usb' : struct phy *phy = phy_get(hcd->self.controller, "usb"); This can get the phy with string 'usb' only if, either the host controller has a device node wherein the phys are given. Even in this case one can't give same constant string for two different phys, UTMI+ and PIPE3 phy, isn't it ? Or, the other way can be when host gets a lookup table to look into to find the relevant phys, something like Heikki has suggested: usb: dwc3: host: convey the PHYs to xhci (https://lkml.org/lkml/2014/6/5/585) and related patch series. So if we use this second approach, we would need to override the 'phy_get()' that has been done in usb_add_hcd() in xhci_plat_probe(), and then use them in later operations. am i getting the things correctly ? -- Best Regards Vivek Gautam Samsung R&D Institute, Bangalore India From mboxrd@z Thu Jan 1 00:00:00 1970 From: gautam.vivek@samsung.com (Vivek Gautam) Date: Wed, 25 Jun 2014 14:14:42 +0530 Subject: [PATCH 2/4] usb: host: xhci-plat: Add support to get PHYs In-Reply-To: <53A9FCDB.6060805@cogentembedded.com> References: <1402056736-12674-1-git-send-email-gautam.vivek@samsung.com> <1402056736-12674-3-git-send-email-gautam.vivek@samsung.com> <53A9FCDB.6060805@cogentembedded.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, On Wed, Jun 25, 2014 at 4:04 AM, Sergei Shtylyov wrote: > Hello. > > > On 06/10/2014 12:22 AM, Julius Werner wrote: > >>> diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h >>> index 9ffecd5..453d89e 100644 >>> --- a/drivers/usb/host/xhci.h >>> +++ b/drivers/usb/host/xhci.h >>> @@ -1582,6 +1582,9 @@ struct xhci_hcd { >>> u32 port_status_u0; >>> /* Compliance Mode Timer Triggered every 2 seconds */ >>> #define COMP_MODE_RCVRY_MSECS 2000 >>> + /* phys for the controller */ >>> + struct phy *phy2_gen; >>> + struct phy *phy3_gen; >>> }; > > >> I don't think adding new variables here and restricting most of this >> logic to xhci-plat.c (in the next patch) is the best way to do it. > > > Indeed. > > >> There's no conceptual reason why other host controllers (e.g. xhci-pci >> or even EHCI) could not have a similar need to tune their PHY after >> reset. PHYs are universal to all host controllers. > > >> There is already a 'phy' member in struct usb_hcd which I think is >> mostly unused right now. I think it would be much less >> confusing/redundant to reuse that member for this purpose (you could >> still set it up from xhci_plat_probe(), and then call it from >> hcd_bus_resume() or something like that). > > > That member has type 'struct usb_phy *' while here we have 'struct phy *' > -- feel the difference. > I have already tried adding 'struct phy *gen_phy' to 'struct usb_hcd', So the 'struct phy *' available in the usb_hcd is requested in usb_add_hcd(). This is requested with the constant string 'usb' : struct phy *phy = phy_get(hcd->self.controller, "usb"); This can get the phy with string 'usb' only if, either the host controller has a device node wherein the phys are given. Even in this case one can't give same constant string for two different phys, UTMI+ and PIPE3 phy, isn't it ? Or, the other way can be when host gets a lookup table to look into to find the relevant phys, something like Heikki has suggested: usb: dwc3: host: convey the PHYs to xhci (https://lkml.org/lkml/2014/6/5/585) and related patch series. So if we use this second approach, we would need to override the 'phy_get()' that has been done in usb_add_hcd() in xhci_plat_probe(), and then use them in later operations. am i getting the things correctly ? -- Best Regards Vivek Gautam Samsung R&D Institute, Bangalore India