From: Felipe Balbi <balbi@kernel.org>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Chen <hzpeterchen@gmail.com>, Leo Li <pku.leo@gmail.com>,
Grygorii Strashko <grygorii.strashko@ti.com>,
Russell King - ARM Linux <linux@arm.linux.org.uk>,
Catalin Marinas <catalin.marinas@arm.com>,
Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
"linux-usb\@vger.kernel.org" <linux-usb@vger.kernel.org>,
Sekhar Nori <nsekhar@ti.com>, lkml <linux-kernel@vger.kernel.org>,
Stuart Yoder <stuart.yoder@nxp.com>,
Scott Wood <oss@buserror.net>,
David Fisher <david.fisher1@synopsys.com>,
"Thang Q. Nguyen" <tqnguyen@apm.com>,
Alan Stern <stern@rowland.harvard.edu>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"linux-arm-kernel\@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH] usb: dwc3: host: inherit dma configuration from parent dev
Date: Wed, 07 Sep 2016 09:51:55 +0300 [thread overview]
Message-ID: <87y434kxro.fsf@linux.intel.com> (raw)
In-Reply-To: <20562703.Glp77l1PBf@wuerfel>
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Arnd Bergmann <arnd@arndb.de> writes:
> On Tuesday, September 6, 2016 1:50:48 PM CEST Felipe Balbi wrote:
>> Hi,
>>
>> Arnd Bergmann <arnd@arndb.de> writes:
>> > On Tuesday, September 6, 2016 9:40:19 AM CEST Felipe Balbi wrote:
>> >>
>> >> this only solves the problem for DT devices. Legacy devices and
>> >> PCI-based systems will still suffer from the same problem. At least for
>> >> dwc3, I will only be taking patches that solve the problem for all
>> >> users, not a subset of them.
>> >
>> > I don't think legacy devices are a worry, because they wouldn't
>> > have this problem. For the PCI case, you are right that it cannot
>> > work, in particular for machines that have complex IOMMU setup.
>> >
>> > Some architectures (at least arm64 and sparc) check the bus_type of
>> > a device in order to find the correct set of dma_map_ops for that
>> > device, so there is no real way to handle this as long as you
>> > pass a platform_device into an API that expects a pci_device.
>>
>> Then I guess we're left with adding a "struct device *dma_dev" to struct
>> dwc3 and trying to figure out if we should use parent or self. Does
>> anybody see any problems with that?
>
> I think we actually need the device pointer in the usb_hcd structure,
> so it can be passed in these API calls from the USB core
that's for host side. I'm concerned about peripheral side
> as these are all called on behalf of the host controller node.
> Looking for more instances of hcd->self.controller, I find this
> instance:
>
> drivers/usb/core/hcd.c: struct usb_phy *phy = usb_get_phy_dev(hcd->self.controller, 0);
> drivers/usb/core/hcd.c: struct phy *phy = phy_get(hcd->self.controller, "usb");
>
> I'm unsure which device pointer we want here, but I suspect this also
> needs to be the one that has the device node in order to make the lookup
> of the phy structure by device node work right. Can you clarify how
> this works today?
sounds correct to me.
--
balbi
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WARNING: multiple messages have this Message-ID (diff)
From: balbi@kernel.org (Felipe Balbi)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] usb: dwc3: host: inherit dma configuration from parent dev
Date: Wed, 07 Sep 2016 09:51:55 +0300 [thread overview]
Message-ID: <87y434kxro.fsf@linux.intel.com> (raw)
In-Reply-To: <20562703.Glp77l1PBf@wuerfel>
Arnd Bergmann <arnd@arndb.de> writes:
> On Tuesday, September 6, 2016 1:50:48 PM CEST Felipe Balbi wrote:
>> Hi,
>>
>> Arnd Bergmann <arnd@arndb.de> writes:
>> > On Tuesday, September 6, 2016 9:40:19 AM CEST Felipe Balbi wrote:
>> >>
>> >> this only solves the problem for DT devices. Legacy devices and
>> >> PCI-based systems will still suffer from the same problem. At least for
>> >> dwc3, I will only be taking patches that solve the problem for all
>> >> users, not a subset of them.
>> >
>> > I don't think legacy devices are a worry, because they wouldn't
>> > have this problem. For the PCI case, you are right that it cannot
>> > work, in particular for machines that have complex IOMMU setup.
>> >
>> > Some architectures (at least arm64 and sparc) check the bus_type of
>> > a device in order to find the correct set of dma_map_ops for that
>> > device, so there is no real way to handle this as long as you
>> > pass a platform_device into an API that expects a pci_device.
>>
>> Then I guess we're left with adding a "struct device *dma_dev" to struct
>> dwc3 and trying to figure out if we should use parent or self. Does
>> anybody see any problems with that?
>
> I think we actually need the device pointer in the usb_hcd structure,
> so it can be passed in these API calls from the USB core
that's for host side. I'm concerned about peripheral side
> as these are all called on behalf of the host controller node.
> Looking for more instances of hcd->self.controller, I find this
> instance:
>
> drivers/usb/core/hcd.c: struct usb_phy *phy = usb_get_phy_dev(hcd->self.controller, 0);
> drivers/usb/core/hcd.c: struct phy *phy = phy_get(hcd->self.controller, "usb");
>
> I'm unsure which device pointer we want here, but I suspect this also
> needs to be the one that has the device node in order to make the lookup
> of the phy structure by device node work right. Can you clarify how
> this works today?
sounds correct to me.
--
balbi
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next prev parent reply other threads:[~2016-09-07 6:52 UTC|newest]
Thread overview: 182+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-04-25 19:21 [PATCH] usb: dwc3: host: inherit dma configuration from parent dev Grygorii Strashko
2016-04-25 19:21 ` Grygorii Strashko
2016-04-26 6:17 ` Felipe Balbi
2016-04-26 6:17 ` Felipe Balbi
2016-04-26 8:14 ` Grygorii Strashko
2016-04-26 8:14 ` Grygorii Strashko
2016-04-27 5:41 ` Felipe Balbi
2016-04-27 5:41 ` Felipe Balbi
2016-04-27 11:55 ` Grygorii Strashko
2016-04-27 11:55 ` Grygorii Strashko
2016-04-27 13:59 ` Catalin Marinas
2016-04-27 13:59 ` Catalin Marinas
2016-04-27 14:11 ` Arnd Bergmann
2016-04-27 14:11 ` Arnd Bergmann
2016-04-27 15:50 ` Catalin Marinas
2016-04-27 15:50 ` Catalin Marinas
2016-04-27 16:04 ` Arnd Bergmann
2016-04-27 16:04 ` Arnd Bergmann
2016-04-27 16:53 ` Felipe Balbi
2016-04-27 16:53 ` Felipe Balbi
2016-04-27 17:42 ` Arnd Bergmann
2016-04-27 17:42 ` Arnd Bergmann
2016-04-27 17:59 ` Alan Stern
2016-04-27 17:59 ` Alan Stern
2016-04-27 18:08 ` Arnd Bergmann
2016-04-27 18:08 ` Arnd Bergmann
2016-04-27 20:05 ` Felipe Balbi
2016-04-27 20:05 ` Felipe Balbi
2016-04-27 21:05 ` Arnd Bergmann
2016-04-27 21:05 ` Arnd Bergmann
2016-04-28 6:37 ` Felipe Balbi
2016-04-28 6:37 ` Felipe Balbi
2016-04-28 14:16 ` Russell King - ARM Linux
2016-04-28 14:16 ` Russell King - ARM Linux
2016-04-28 14:23 ` Arnd Bergmann
2016-04-28 14:23 ` Arnd Bergmann
2016-04-28 14:27 ` Felipe Balbi
2016-04-28 14:27 ` Felipe Balbi
2016-09-01 22:14 ` Leo Li
2016-09-01 22:14 ` Leo Li
2016-09-02 10:43 ` Arnd Bergmann
2016-09-02 10:43 ` Arnd Bergmann
2016-09-02 10:47 ` Russell King - ARM Linux
2016-09-02 10:47 ` Russell King - ARM Linux
2016-09-02 11:08 ` Felipe Balbi
2016-09-02 11:08 ` Felipe Balbi
2016-09-02 14:11 ` Felipe Balbi
2016-09-02 14:11 ` Felipe Balbi
2016-09-02 14:21 ` Alan Stern
2016-09-02 14:21 ` Alan Stern
2016-09-02 15:51 ` Arnd Bergmann
2016-09-02 15:51 ` Arnd Bergmann
2016-09-07 7:17 ` Roger Quadros
2016-09-07 7:17 ` Roger Quadros
2016-09-07 8:29 ` Arnd Bergmann
2016-09-07 8:29 ` Arnd Bergmann
2016-09-07 13:04 ` Roger Quadros
2016-09-07 13:04 ` Roger Quadros
2016-09-07 14:38 ` Arnd Bergmann
2016-09-07 14:38 ` Arnd Bergmann
2016-09-02 16:23 ` Grygorii Strashko
2016-09-02 16:23 ` Grygorii Strashko
2016-09-02 10:53 ` Felipe Balbi
2016-09-02 10:53 ` Felipe Balbi
2016-09-02 11:55 ` Robin Murphy
2016-09-02 11:55 ` Robin Murphy
2016-09-02 12:56 ` Felipe Balbi
2016-09-02 12:56 ` Felipe Balbi
2016-09-02 13:10 ` Arnd Bergmann
2016-09-02 13:10 ` Arnd Bergmann
2016-09-02 22:16 ` Leo Li
2016-09-02 22:16 ` Leo Li
2016-09-05 15:39 ` Arnd Bergmann
2016-09-05 15:39 ` Arnd Bergmann
2016-09-06 6:35 ` Peter Chen
2016-09-06 6:35 ` Peter Chen
2016-09-06 6:40 ` Felipe Balbi
2016-09-06 6:40 ` Felipe Balbi
2016-09-06 10:46 ` Arnd Bergmann
2016-09-06 10:46 ` Arnd Bergmann
2016-09-06 10:50 ` Felipe Balbi
2016-09-06 10:50 ` Felipe Balbi
2016-09-06 13:27 ` Arnd Bergmann
2016-09-06 13:27 ` Arnd Bergmann
2016-09-07 6:51 ` Felipe Balbi [this message]
2016-09-07 6:51 ` Felipe Balbi
2016-09-07 7:44 ` Peter Chen
2016-09-07 7:44 ` Peter Chen
2016-09-07 8:52 ` Arnd Bergmann
2016-09-07 8:52 ` Arnd Bergmann
2016-09-07 9:29 ` Peter Chen
2016-09-07 9:29 ` Peter Chen
2016-09-07 9:35 ` Russell King - ARM Linux
2016-09-07 9:35 ` Russell King - ARM Linux
2016-09-07 10:18 ` Felipe Balbi
2016-09-07 10:18 ` Felipe Balbi
2016-09-06 10:38 ` Arnd Bergmann
2016-09-06 10:38 ` Arnd Bergmann
2016-09-07 6:33 ` Peter Chen
2016-09-07 6:33 ` Peter Chen
2016-09-07 8:48 ` Arnd Bergmann
2016-09-07 8:48 ` Arnd Bergmann
2016-09-07 9:55 ` Peter Chen
2016-09-07 9:55 ` Peter Chen
2016-09-07 10:33 ` Robin Murphy
2016-09-07 10:33 ` Robin Murphy
2016-09-07 10:47 ` Felipe Balbi
2016-09-07 10:47 ` Felipe Balbi
2016-09-14 16:31 ` Lorenzo Pieralisi
2016-09-14 16:31 ` Lorenzo Pieralisi
2016-09-14 21:50 ` Arnd Bergmann
2016-09-14 21:50 ` Arnd Bergmann
2016-09-07 10:24 ` Felipe Balbi
2016-09-07 10:24 ` Felipe Balbi
2016-09-07 15:24 ` Arnd Bergmann
2016-09-07 15:24 ` Arnd Bergmann
2016-09-07 16:08 ` Alan Stern
2016-09-07 16:08 ` Alan Stern
2016-09-07 19:45 ` Arnd Bergmann
2016-09-07 19:45 ` Arnd Bergmann
2016-09-08 1:15 ` Peter Chen
2016-09-08 1:15 ` Peter Chen
2016-09-08 8:02 ` Arnd Bergmann
2016-09-08 8:02 ` Arnd Bergmann
2016-09-08 8:03 ` Felipe Balbi
2016-09-08 8:03 ` Felipe Balbi
2016-09-08 8:26 ` Arnd Bergmann
2016-09-08 8:26 ` Arnd Bergmann
2016-09-08 8:29 ` Felipe Balbi
2016-09-08 8:29 ` Felipe Balbi
2016-09-08 8:45 ` Arnd Bergmann
2016-09-08 8:45 ` Arnd Bergmann
2016-09-08 9:43 ` Felipe Balbi
2016-09-08 9:43 ` Felipe Balbi
2016-09-08 10:17 ` Arnd Bergmann
2016-09-08 10:17 ` Arnd Bergmann
2016-09-08 11:00 ` Felipe Balbi
2016-09-08 11:00 ` Felipe Balbi
2016-09-08 11:11 ` Arnd Bergmann
2016-09-08 11:11 ` Arnd Bergmann
2016-09-08 11:20 ` Felipe Balbi
2016-09-08 11:20 ` Felipe Balbi
2016-09-08 11:39 ` Arnd Bergmann
2016-09-08 11:39 ` Arnd Bergmann
2016-09-08 11:52 ` Felipe Balbi
2016-09-08 11:52 ` Felipe Balbi
2016-09-08 12:46 ` Arnd Bergmann
2016-09-08 12:46 ` Arnd Bergmann
2016-09-08 12:02 ` Grygorii Strashko
2016-09-08 12:02 ` Grygorii Strashko
2016-09-08 12:14 ` Arnd Bergmann
2016-09-08 12:14 ` Arnd Bergmann
2016-09-08 12:28 ` Peter Chen
2016-09-08 12:28 ` Peter Chen
2016-09-08 12:52 ` Arnd Bergmann
2016-09-08 12:52 ` Arnd Bergmann
2016-09-09 1:37 ` Peter Chen
2016-09-09 1:37 ` Peter Chen
2016-09-08 12:59 ` Grygorii Strashko
2016-09-08 12:59 ` Grygorii Strashko
2016-09-09 1:52 ` Peter Chen
2016-09-09 1:52 ` Peter Chen
2016-09-21 11:06 ` Sriram Dash
2016-09-21 11:06 ` Sriram Dash
2016-09-21 11:31 ` Arnd Bergmann
2016-09-21 11:31 ` Arnd Bergmann
2016-09-21 11:43 ` Sriram Dash
2016-09-21 11:43 ` Sriram Dash
2016-09-21 12:48 ` Arnd Bergmann
2016-09-21 12:48 ` Arnd Bergmann
2016-09-22 5:02 ` Sriram Dash
2016-09-22 5:02 ` Sriram Dash
2016-10-07 22:46 ` Leo Li
2016-10-07 22:46 ` Leo Li
2016-09-21 17:14 ` [PATCH] usb: xhci: Fix the patch inherit dma configuration from kbuild test robot
2016-09-21 17:14 ` kbuild test robot
2016-04-27 20:57 ` [PATCH] usb: dwc3: host: inherit dma configuration from parent dev Felipe Balbi
2016-04-27 20:57 ` Felipe Balbi
2016-04-27 14:14 ` Grygorii Strashko
2016-04-27 14:14 ` Grygorii Strashko
2016-05-05 17:07 ` Brian Norris
2016-05-05 17:07 ` Brian Norris
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