Re: [PATCH] ARM: multi_v7_defconfig: enable usb3503

[Kevin Hilman <khilman@kernel.org>]

Javier Martinez Canillas <javier.martinez@collabora.co.uk> writes:

> Hello Kevin,
>
> On 06/04/2015 03:08 AM, Kevin Hilman wrote:
>> riku.voipio@linaro.org writes:
>> 
>>> From: Riku Voipio <riku.voipio@linaro.org>
>>>
>>> CONFIG_USB_HSIC_USB3503 is needed by exynos5250-arndale for the on-board
>>> asix network controller. Enable it so networking works with
>>> multi_v7_defconfig out of box like it does with exynos_defconfig.
>>>
>>> USB3503 is also referenced from exynos4412-odroidu3.dts and
>>> exynos5250-spring.dts so this patch should improve
>>> multi_v7_defconfig on those platforms as well.
>>>
>>> Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
>> 
>> Tyler pointed me to this in order to get arndale networking on mainline,
>> but looks like this might need to be revisited for current mainline.  
>> 
>> I tested this and it doesn't work because as of commit 7de7c6717f2c
>> (ARM: multi_v7_defconfig: Enable Exynos USB PHY) the PHY that this
>> depends on is built as a module in multi_v7_config, so having this
>> driver built-in doesn't help.  Even after the PHY driver is loaded, this
>> driver will not detect the hardware.
>> 
>> So instead, I think this driver should be built as a module as well.
>> Testing that, I can get networking by doing loading both the phy and
>> this driver after boot:
>> 
>>  # modprobe phy-exynos-usb2
>>  # modprobe usb3503
>>
>
> Current policy is to have as much as possible built as a module
> in multi_v7_config so regardless of your issue I think that the
> patch should be re-spun to change this.

Correct.

> But I wonder why is not working, shouldn't the driver defer and
> be probed again once the PHY driver probe succeeds?

Yeah, I'm not sure why that isn't working, and didn't look into it.

FWIW, the same problem happens when both are modules.  If you modprobe
usb3503 first, then the phy, it doesn't work.  You have to load the phy
before the usb3503.

Kevin