[PATCH 1/5] phy: sun4i: add support for USB phy0

Chen-Yu Tsai wens at csie.org
Tue Oct 28 19:24:12 PDT 2014


On Wed, Oct 29, 2014 at 5:47 AM, Maxime Ripard
<maxime.ripard at free-electrons.com> wrote:
> Hi Roman,
>
> Thanks for your patches
>
> On Mon, Oct 27, 2014 at 10:43:01PM +0100, Roman Byshko wrote:
>> The driver for sun4i USB phys currently supports
>> only phy1 and phy2 which are used for USB host
>> controllers. This patch adds support for USB phy0,
>> which is used by the musb hdrc USB controller.
>
> Like Andreas already pointed out, your signed-off-by is missing from
> all your patches.
>
>> ---
>>  drivers/phy/phy-sun4i-usb.c | 9 ++++++---
>>  1 file changed, 6 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/phy/phy-sun4i-usb.c b/drivers/phy/phy-sun4i-usb.c
>> index 0baf5ef..a24728b 100644
>> --- a/drivers/phy/phy-sun4i-usb.c
>> +++ b/drivers/phy/phy-sun4i-usb.c
>> @@ -157,6 +157,10 @@ static int sun4i_usb_phy_init(struct phy *_phy)
>>               return ret;
>>       }
>>
>> +     /* Regulation 45 ohms */
>> +     if (phy->index == 0)
>> +             sun4i_usb_phy_write(phy, PHY_RES45_CAL_EN, 0x01, 1);
>
> What is this code supposed to do?
>
> Some define for this bit and/or a better comment would be nice.

>From Allwinner's sources: "Enable/Disable USB res45 Calibration"

which I think refers to the internal 45 ohm termination resistors
for the USB data lines. But I'm not an expert on USB hardware.



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