Re: [PATCH v4 5/9] usb: dwc3: core: make dual-role work with OTG irq

[Roger Quadros <rogerq@ti.com>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256

On 03/09/15 18:51, Felipe Balbi wrote:
> Hi,
> 
> On Thu, Sep 03, 2015 at 04:52:02PM +0300, Roger Quadros wrote:
>>>>  	if (on) {
>>>> -		dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_HOST);
>>>> +		/* OCTL.PeriMode = 0 */
>>>> +		reg = dwc3_readl(dwc->regs, DWC3_OCTL);
>>>> +		reg &= ~DWC3_OCTL_PERIMODE;
>>>> +		dwc3_writel(dwc->regs, DWC3_OCTL, reg);
>>>> +		/* unconditionally turn on VBUS */
>>>> +		reg |= DWC3_OCTL_PRTPWRCTL;
>>>> +		dwc3_writel(dwc->regs, DWC3_OCTL, reg);
>>>>  		/* start the HCD */
>>>>  		usb_otg_start_host(fsm, true);
>>>>  	} else {
>>>>  		/* stop the HCD */
>>>>  		usb_otg_start_host(fsm, false);
>>>> +		/* turn off VBUS */
>>>> +		reg = dwc3_readl(dwc->regs, DWC3_OCTL);
>>>> +		reg &= ~DWC3_OCTL_PRTPWRCTL;
>>>> +		dwc3_writel(dwc->regs, DWC3_OCTL, reg);
>>>> +		/* OCTL.PeriMode = 1 */
>>>> +		reg = dwc3_readl(dwc->regs, DWC3_OCTL);
>>>> +		reg |= DWC3_OCTL_PERIMODE;
>>>> +		dwc3_writel(dwc->regs, DWC3_OCTL, reg);
>>>>  	}
>>>
>>> it looks like you're not really following the fluxchart from SNPS
>>> documentation, see Figure 11-4 on section 11.1.4.5
>>
>> Did you mean that I'm ignoring all OTG bits (HNP/SRP/ADP)?
> 
> yes and no :-)  There's a rather complex flux chart which details how we
> switch from host to peripheral and vice versa. We need to follow that to
> the smallest details since that's what IP provider considers to be
> correct. If we deviate from that we should have very strong reasons for
> doing so and we also want big, fat, long comments in source code
> detailing why and how we're deviating :-)
> 
Understood. I'll update this accordingly.

- --
cheers,
- -roger
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
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=L39b
-----END PGP SIGNATURE-----