Hi Marek, > -----Original Message----- > From: Marek Vasut [mailto:ma...@denx.de] > Sent: Thursday, December 22, 2016 4:58 PM > To: Peng Fan <peng....@nxp.com>; sba...@denx.de > Cc: u-boot@lists.denx.de; van.free...@gmail.com > Subject: Re: [PATCH 3/3] imx: mx6sllevk: add usb support > > On 12/22/2016 09:55 AM, Peng Fan wrote: > > > > > >>>>>>>>>>> +#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? > >>>> > >>>> So uh, how can the USB work in mainline Linux on that board ? > >>> > >>> Confirmed with IC, if using gpio to control vbus power, no need to > >>> configure > >> this bit. > >>> Since in dts, we are using gpio regulator to control vbus, this > >>> piece code in patch 3/3 can be discarded. I'll drop it in V2. > >> > >> Hum, OK. Let's revisit this when we need this then ? > > > > Take i.MX6SLL as an example, > > The pin key_col4 can be configured with the two functions. > > [1] MX6_PAD_KEY_COL4__USB_OTG1_PWR > > [2] MX6_PAD_KEY_COL4__GPIO4_IO00 > > > > In fsl i.mx uboot code, the common way is to use [1] and configure the > polarity to enable the vbus power. > > But in kernel, it is configured as [2] and use gpio regulator to enable the > > vbus > power. > > > > This is board specific. There is no upstream property for this bit. > > When there is an upstream property for this, We could add it in probe > function for those that use [1] in dts pinmux. > > > > Now I am using the same dts from kernel which this pinmux configured as [2], > so this piece code is not needed for now. > > Well, can you submit a proposal with the new prop for devicetree@ ? > It can then be improved in linux too ...
I'll talk with our internal Linux usb maintainer to see whether he has plan to do this. Thanks, Peng. > > -- > Best regards, > Marek Vasut _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
