Re: [PATCH v3 0/5] usb: phy: samsung: Introducing usb phy driver for samsung SoCs

From: Praveen Paneri <p.paneri@samsung.com>
To: balbi@ti.com
Cc: Joonyoung Shim <jy0922.shim@samsung.com>,
	linux-usb@vger.kernel.org, l.majewski@samsung.com,
	kgene.kim@samsung.com, heiko@sntech.de,
	gregkh@linuxfoundation.org, devicetree-discuss@lists.ozlabs.org,
	broonie@opensource.wolfsonmicro.com, grant.likely@secretlab.ca,
	kyungmin.park@samsung.com, linux-samsung-soc@vger.kernel.org,
	thomas.abraham@linaro.org, ben-linux@fluff.org,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v3 0/5] usb: phy: samsung: Introducing usb phy driver for samsung SoCs
Date: Fri, 10 Aug 2012 11:54:32 +0530	[thread overview]
Message-ID: <CAD6zSYMC072bMqMPTmsH4ZzTAd4OmFk5TVpcxAAu82b7J9jNHw@mail.gmail.com> (raw)
In-Reply-To: <20120810061616.GC1689@arwen.pp.htv.fi>

On Fri, Aug 10, 2012 at 11:46 AM, Felipe Balbi <balbi@ti.com> wrote:
> HI,
>
> On Fri, Aug 10, 2012 at 11:17:29AM +0530, Praveen Paneri wrote:
>> On Fri, Aug 10, 2012 at 7:03 AM, Joonyoung Shim <jy0922.shim@samsung.com> wrote:
>> > Hi, Praveen.
>> >
>> >
>> > On 08/08/2012 04:40 PM, Praveen Paneri wrote:
>> >>
>> >> Changes from v2:
>> >> Changed the driver filenames to samsung-usbphy
>> >> Changed 's3c' to 'samsung' for platform device as well as platform data
>> >> Moved platform data structure to a separate file
>> >> Rectified coding style related errors
>> >>
>> >> Changes from v1:
>> >> Rebased patches to latest usb-next branch
>> >> Changed the name 'sec_usbphy' to 'samsung_usbphy'
>> >>
>> >> This patch set introduces a phy driver for samsung SoCs. It uses the
>> >> existing
>> >> transceiver infrastructure to provide phy control functions. Use of this
>> >> driver
>> >> can be extended for usb host phy as well.
>> >
>> >
>> > How can you support usb host phy? I cannot choose to use which phy when
>> > call init or shutdown of phy at current phy framework.
>
> correct. Curretly that's not supported. We are trying to come up with
> proper DeviceTree bindings to allow that. Kishon has been working on
> providing devm_usb_get_phy_by_phandle() would should help achieving what
> you need.
>
>> If you are talking about choosing between PHY0 (for device) and PHY1
>> (for host), I think you can make use of the flags available in usb_phy
>> to pass that information to phy driver and that can be handled there.
>
> I rather you didn't do it that way. Those flags are used to pass
> features to the PHY. See drivers/usb/otg/ulpi.c, for instance.
>
>> This is just one way I have successfully implement two different phy
>> control. There might be a better way to do that.
>
> I guess using DT phandles is the way to go here.
off-course! That is why I haven't included host support as of now.

Praveen
>
> --
> balbi