[U-Boot] [PATCH 3/3] imx: mx6sllevk: add usb support

[Peng Fan]

> -----Original Message-----
> From: Marek Vasut [mailto:marex at denx.de]
> Sent: Thursday, December 22, 2016 2:12 PM
> To: Peng Fan <peng.fan at nxp.com>; sbabic at denx.de
> Cc: u-boot at lists.denx.de; van.freenix at gmail.com
> Subject: Re: [PATCH 3/3] imx: mx6sllevk: add usb support
> 
> On 12/22/2016 07:03 AM, Peng Fan wrote:
> >
> > Hi Marek,
> >
> >> -----Original Message-----
> >> From: Marek Vasut [mailto:marex at denx.de]
> >> Sent: Thursday, December 22, 2016 12:40 PM
> >> To: Peng Fan <peng.fan at nxp.com>; sbabic at denx.de
> >> Cc: u-boot at lists.denx.de; van.freenix at gmail.com
> >> Subject: Re: [PATCH 3/3] imx: mx6sllevk: add usb support
> >>
> >> On 12/22/2016 02:13 AM, Peng Fan wrote:
> >>>
> >>>
> >>>> -----Original Message-----
> >>>> From: Marek Vasut [mailto:marex at denx.de]
> >>>> Sent: Wednesday, December 21, 2016 10:10 PM
> >>>> To: Peng Fan <peng.fan at nxp.com>; sbabic at denx.de
> >>>> Cc: u-boot at lists.denx.de; van.freenix at gmail.com
> >>>> Subject: Re: [PATCH 3/3] imx: mx6sllevk: add usb support
> >>>>
> >>>> On 12/21/2016 09:14 AM, Peng Fan wrote:
> >>>>> Add usb support for mx6sllevk board.
> >>>>>
> >>>>> Signed-off-by: Peng Fan <peng.fan at nxp.com>
> >>>>> Cc: Stefano Babic <sbabic at denx.de>
> >>>>> ---
> >>> [......]
> >>>
> >>>>> +
> >>>>> +#define USB_OTHERREGS_OFFSET   0x800
> >>>>> +#define UCTRL_PWR_POL          (1 << 9)
> >>>>> +
> >>>>> +int board_ehci_hcd_init(int port) {
> >>>>> +	u32 *usbnc_usb_ctrl;
> >>>>> +
> >>>>> +	if (port > 1)
> >>>>> +		return -EINVAL;
> >>>>> +
> >>>>> +	usbnc_usb_ctrl = (u32 *)(USB_BASE_ADDR +
> USB_OTHERREGS_OFFSET
> >>>> +
> >>>>> +				 port * 4);
> >>>>> +
> >>>>> +	/* Set Power polarity */
> >>>>> +	setbits_le32(usbnc_usb_ctrl, UCTRL_PWR_POL);
> >>>>> +	return 0;
> >>>>> +}
> >>>>
> >>>> Is this function similar to what usb_oc_config() does ?
> >>>
> >>> No, this bit is not for overcurrent. According to RM, this is OTG
> >>> Power Polarity This bit should be set according to power switch's
> >>> enable
> >> polarity.
> >>> 1 Power switch has an active-high enable input
> >>> 0 Power switch has an active-low enable input
> >>>
> >>> This is board specific.
> >>
> >> Great, except it should also be part of the driver , the same way as
> >> polarity is configured, yes ?
> >
> > I just found that there is code for mx7,
> > http://lists.denx.de/pipermail/u-boot/2016-July/260321.html
> >
> > Then do you agree I add such piece code in usb_power_config for mx6?
> > "
> > #ifdef CONFIG_MXC_USB_OTG_HACTIVE
> >         setbits_le32(ctrl, UCTRL_PWR_POL); #else
> >         clrbits_le32(ctrl, UCTRL_PWR_POL);
> > #endif
> > "
> 
> Didn't you add DT support in a patch sent like ... yesterday ? :) Just use DT
> property instead of ifdef.

There is no property for otg power polatiry in upstream Linux. I would not like to introduce one
in U-Boot. We can drop the ifdef when there is an property in upstream. What do you think?

Regards,
Peng.

> 
> --
> Best regards,
> Marek Vasut