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Subject: Re: [RFC 1/5] usb: chipidea: Add support for Tegra20/30/114/124
To: Thierry Reding <thierry.reding@gmail.com>
References: <20160526154005.11558-1-thierry.reding@gmail.com>
 <20160526154005.11558-2-thierry.reding@gmail.com>
Cc: Peter Chen <Peter.Chen@nxp.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Alexandre Courbot <gnurou@gmail.com>,
        Jon Hunter <jonathanh@nvidia.com>, linux-usb@vger.kernel.org,
        linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org
From: Stephen Warren <swarren@wwwdotorg.org>
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Date: Thu, 26 May 2016 15:17:12 -0600
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On 05/26/2016 09:40 AM, Thierry Reding wrote:
> From: Thierry Reding <treding@nvidia.com>
>
> All of these Tegra SoC generations have a ChipIdea UDC IP block that can
> be used for device mode communication with a host. Implement rudimentary
> support that doesn't allow switching between host and device modes.

Are you sure this is correct for Tegra20? I ask because for the /host/ 
mode driver, there's a "has_hostpc" flag which is set to false for 
Tegra20 and true for all other SoCs. In the U-Boot device mode driver 
(if not in the kernel driver; I didn't check), there's a concept of "has 
hostpc" too. I might expect that flag to be set the same way for both 
drivers. That said, I /think/ the host and device HW are unrelated, so 
it's possible has_hostpc might be set differently for them. 
Unfortunately, we haven't enabled the device mode driver for any Tegra20 
system in U-Boot so I can't tell whether we should enable has_hostpc for 
Tegra20's device mode driver.

Still, if this code works then I guess it's likely correct...