Re: [PATCH] phy: Add a driver for dm816x USB PHY

From: Bin Liu <binmlist@gmail.com>
To: Tony Lindgren <tony@atomide.com>
Cc: Felipe Balbi <balbi@ti.com>,
	Kishon Vijay Abraham I <kishon@ti.com>,
	linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org,
	linux-usb <linux-usb@vger.kernel.org>,
	Brian Hutchinson <b.hutchman@gmail.com>
Subject: Re: [PATCH] phy: Add a driver for dm816x USB PHY
Date: Tue, 10 Mar 2015 09:35:32 -0500	[thread overview]
Message-ID: <CADYTM3aRMboKrYrdoRAkeL1=J_Sfvgf3vDx_AEJa_qKfneQs9A@mail.gmail.com> (raw)
In-Reply-To: <20150309214129.GK5264@atomide.com>

On Mon, Mar 9, 2015 at 4:41 PM, Tony Lindgren <tony@atomide.com> wrote:
> * Bin Liu <binmlist@gmail.com> [150309 14:35]:
>> On Mon, Mar 9, 2015 at 4:26 PM, Tony Lindgren <tony@atomide.com> wrote:
>> > * Felipe Balbi <balbi@ti.com> [150309 14:21]:
>> >> On Mon, Mar 09, 2015 at 04:17:29PM -0500, Bin Liu wrote:
>> >> > On Mon, Mar 9, 2015 at 4:13 PM, Felipe Balbi <balbi@ti.com> wrote:
>> >> > > On Mon, Mar 09, 2015 at 04:11:28PM -0500, Bin Liu wrote:
>> >> > >> Hi,
>> >> > >>
>> >> > >> On Mon, Mar 9, 2015 at 3:51 PM, Tony Lindgren <tony@atomide.com> wrote:
>> >> > >> > Add a minimal driver for dm816x USB. Otherwise we can just use
>> >> > >> > the existing musb_am335x and musb_dsps on dm816x.
>> >> > >>
>> >> > >> dm816x has the almost identical usbss as that in am335x, we should be
>> >> > >> able to adopt musb_am335x and musb_dsps for dm816x, and dm814x too?
>> >> > >
>> >> > > Tony's using the same musb glue layers, this is just a phy driver,
>> >> > > right ?
>> >> >
>> >> > Can the current am335x phy driver be adopted too? I remember it is
>> >> > under drivers/usb/phy/.
>> >>
>> >> Tony will be best to answer, but according to our IRC discussions, it's
>> >> too different. Tony ?
>> >
>> > Well we should check again between dm814x and am335x documentation
>> > against the $subject driver as the dm816x docs were buggy and I may
>> > have gotten a wrong idea initially.
>>
>> Will it make our life a little easier by comparing the usb drivers for
>> dm81xx and am335x in previous TI kernel releases? I cam dig out the
>> source code if that helps.
>
> Yeah that probably helps if you've dealt with dm814x earlier :)

Well, don't expect much from me about dm814x ;), I did not read its
trm nor errata, but only booted the board a few times trying to
compare the MUSB behaviours while debugging issues on am335x.

Ok, the previous TI released 3.2 kernel for am335x is at [1], and
2.6.37 kernel dm81xx is at [2].

Regards,
-Bin.

[1] http://arago-project.org/git/projects/?p=linux-am33x.git;a=shortlog;h=refs/heads/v3.2-staging

[2] http://arago-project.org/git/projects/?p=linux-omap3.git;a=shortlog;h=refs/heads/TI81XXPSP_04.04.00.01

> Just don't look at the dm816x trm, only the errata pdf works for
> dm816x phy.
>
> Note that we still are missing basic support for dm814x in mainline,
> I'm planning to tackle that at some point but I don't know when I'm
> going to get to it..
>
> Regards,
>
> Tony