Re: [PATCH v4 2/2] usb: dwc2: add 'mode' which based on Kconfig select or dts setting

From: Dinh Nguyen
Date: Wed Aug 06 2014 - 23:14:30 EST



On 8/6/14, 5:57 PM, Paul Zimmerman wrote:
>> From: dianders@xxxxxxxxxx [mailto:dianders@xxxxxxxxxx] On Behalf Of Doug Anderson
>> Sent: Wednesday, August 06, 2014 3:25 PM
>>
>> On Tue, Aug 5, 2014 at 6:01 PM, Kever Yang <kever.yang@xxxxxxxxxxxxxx> wrote:
>>> According to the "dr_mode", the otg controller can work as
>>> device role and host role. Some boards always want to use host mode
>>> and some other boards want to use gadget mode. We use the dts setting
>>> to set dwc2's mode, rather than fixing it to whatever hardware says.
>>>
>>> Signed-off-by: Kever Yang <kever.yang@xxxxxxxxxxxxxx>
>>> Acked-by: Paul Zimmerman <paulz@xxxxxxxxxxxx>
>>> ---
>>>
>>> Changes in v4:
>>> - From Doug's suggestion:
>>> -- remove dr_mode init from Kconfig code
>>> -- change the commit meesage
>>>
>>> Changes in v3:
>>> - fix the odd spacing in dwc2_hsotg struct
>>> - From Jingoo's suggestion:
>>> change the commit message
>>> - add dr_mode init from Kconfig
>>>
>>> Changes in v2:
>>> - put spaces around '+' operator
>>> - expand the comment for dr_mode
>>> - handle dr_mode is USB_DR_MODE_OTG
>>>
>>> drivers/usb/dwc2/core.c | 18 ++++++++++++++++++
>>> drivers/usb/dwc2/core.h | 5 +++++
>>> drivers/usb/dwc2/platform.c | 4 ++++
>>> 3 files changed, 27 insertions(+)
>> I think this patch still makes sense even though we don't have a
>> combined driver yet. Perhaps Paul or Dihn can confirm.
> Yes, it should be fine.
>
>> We could potentially do something based on KConfig (like you did in
>> patch set #3), but it wouldn't really make sense to do that until
>> after Dihn's work lands.
>>
>>
>>> diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c
>>> index 27d2c9b..738bec2 100644
>>> --- a/drivers/usb/dwc2/core.c
>>> +++ b/drivers/usb/dwc2/core.c
>>> @@ -118,6 +118,7 @@ static int dwc2_core_reset(struct dwc2_hsotg *hsotg)
>>> {
>>> u32 greset;
>>> int count = 0;
>>> + u32 gusbcfg;
>>>
>>> dev_vdbg(hsotg->dev, "%s()\n", __func__);
>>>
>>> @@ -148,6 +149,23 @@ static int dwc2_core_reset(struct dwc2_hsotg *hsotg)
>>> }
>>> } while (greset & GRSTCTL_CSFTRST);
>>>
>>> + if (hsotg->dr_mode == USB_DR_MODE_HOST) {
>>> + gusbcfg = readl(hsotg->regs + GUSBCFG);
>>> + gusbcfg &= ~GUSBCFG_FORCEDEVMODE;
>>> + gusbcfg |= GUSBCFG_FORCEHOSTMODE;
>>> + writel(gusbcfg, hsotg->regs + GUSBCFG);
>>> + } else if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL) {
>>> + gusbcfg = readl(hsotg->regs + GUSBCFG);
>>> + gusbcfg &= ~GUSBCFG_FORCEHOSTMODE;
>>> + gusbcfg |= GUSBCFG_FORCEDEVMODE;
>>> + writel(gusbcfg, hsotg->regs + GUSBCFG);
>>> + } else if (hsotg->dr_mode == USB_DR_MODE_OTG) {
>>> + gusbcfg = readl(hsotg->regs + GUSBCFG);
>>> + gusbcfg &= ~GUSBCFG_FORCEHOSTMODE;
>>> + gusbcfg &= ~GUSBCFG_FORCEDEVMODE;
>>> + writel(gusbcfg, hsotg->regs + GUSBCFG);
>> I think the third case here won't be too useful until the combined
>> driver, but it shouldn't hurt, right?
> Right. For the existing drivers, it shouldn't change anything, since
> nothing currently sets dr_mode. And with Kever's other patches, it
> forces host mode on the Rockchip platform, which is all that is required
> for now, if I understand correctly.
>
I managed to test this patch on the SOCFPGA platform. So

Tested-by: Dinh Nguyen <dinguyen@xxxxxxxxxxxxxxxxxxxxx>

Thanks,
DInh

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/