[RFC v2 11/13] usb: port: Parse pwrseq phandle from Device Tree

Krzysztof Kozlowski k.kozlowski at samsung.com
Thu May 5 23:27:35 PDT 2016


On 05/05/2016 10:10 PM, Javier Martinez Canillas wrote:
> Hello Krzysztof,
> 
> On 05/05/2016 08:34 AM, Krzysztof Kozlowski wrote:
>> Parse usb-pwrseq property from Device Tree to get the phandle to pwrseq
>> device. The pwrseq device will be used by USB hub to cycle the power
>> before activating ports.
>>
>> Signed-off-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
>> ---
> 
> [snip]
> 
>>  
>> @@ -532,6 +534,14 @@ int usb_hub_create_port_device(struct usb_hub *hub, int port1)
>>  		return retval;
>>  	}
>>  
>> +	port_dev->dev.of_node = usb_of_get_child_node(hub->hdev->dev.of_node, port1);
>> +	port_dev->pwrseq = pwrseq_alloc(&port_dev->dev);
>> +	if (IS_ERR(port_dev->pwrseq)) {
>> +		device_unregister(&port_dev->dev);
>> +		/* TODO: what about EPROBE_DEFER? */
> 
> I think it's OK since the call chain is:
> 
> hub_probe()
>        hub_configure()
>               usb_hub_create_port_device()
> 
> so the hub_probe() will be deferred if the usb-pwrseq was not registered yet.
> Unless I misunderstood your question :)
> 
> Anyway, patch looks good to me:
> 
> Reviewed-by: Javier Martinez Canillas <javier at osg.samsung.com>

Yes and deferred probing works in my case. That is an older comment
actually.

Thanks for review,
Krzysztof




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