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

On Wed, Oct 29, 2014 at 10:24:12AM +0800, Chen-Yu Tsai wrote:
> On Wed, Oct 29, 2014 at 5:47 AM, Maxime Ripard
> <maxime.ripard@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.

That would make a great comment ;)

Maxime

--
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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