Re: [PATCH v4 3/3] usb: chipidea: register driver as a peripheral with the phy

[Tim Bird <tim.bird@sonymobile.com>]

On 11/23/2015 12:29 AM, Peter Chen wrote:
> On Fri, Nov 20, 2015 at 03:47:20PM -0800, Tim Bird wrote:
>> Register the chipidea driver with the phy, so that the phy
>> driver can kick the gadget driver when it resumes from low power.
>> The phy-msm-usb (Qualcomm) driver requires this in order to
>> recover gadget operation after you disconnect the USB cable
>> and reconnect it.
>>
>> Signed-off-by: Tim Bird <tim.bird@sonymobile.com>
>> ---
>>  drivers/usb/chipidea/udc.c | 6 ++++++
>>  1 file changed, 6 insertions(+)
>>
>> diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
>> index 8223fe7..06234cd 100644
>> --- a/drivers/usb/chipidea/udc.c
>> +++ b/drivers/usb/chipidea/udc.c
>> @@ -1890,6 +1890,12 @@ static int udc_start(struct ci_hdrc *ci)
>>  
>>  	ci->gadget.ep0 = &ci->ep0in->ep;
>>  
>> +	if (ci->usb_phy) {
>> +		retval = otg_set_peripheral(ci->usb_phy->otg, &ci->gadget);
>> +		if (retval)
>> +			goto destroy_eps;
>> +	}
>> +
>>  	retval = usb_add_gadget_udc(dev, &ci->gadget);
>>  	if (retval)
>>  		goto destroy_eps;
> 
> Hi Tim,
> 
> I am afraid it can't work for current chipidea framework (find this
> problem after testing), the chipidea core manages its host and device
> function using its own API start/stop, it does not define struct usb_otg
> APIs. In fact, it is not reasonable control host and device function
> at PHY driver.

OK.  I'm going to re-evaluate the phy-msm-usb.c code, and try to figure out
what it should look like under the current framework.

Thanks for looking at it and testing it.  I may have questions as I go.
 -- Tim