I have had a look into the spec (USB PD), but it does not explicitly explain whether the negotiation is done in hardware (by dedicated charger chips) or driver software (which then assigns higher allowed current to the ports). We are planning for new devices to be designed, where we want to support charging smartphones etc. and we want to know if there has to be done something for this in the USB drivers, and from which kernel on the PD will be supported. Actually it seems that the negotiation is a job for the charger chips and they signal their state via GPIOs to CPU/SoC. However, I think that the USB team should have an eye on the USB PD spec. and keep it in mind. Thanks, Carsten XS Embedded GmbH Peterzeller Straße 8 D-78048 Villingen - Schwenningen Telefon +49 (7721) 4060 - 442 Fax +49 (7721) 4060 - 499 www.xse.de carsten_schmid@xxxxxxxxxx :::::::::: based.on.visions :::::::::: XS Embedded GmbH Geschäftsführung: Dean Freed, Walter Vermijs, Shannon Wetzel Handelsregister: Amtsgericht Freiburg i.Br., HRB 705237 Sitz der Gesellschaft: Peterzeller Straße 8, 78048 Villingen-Schwenningen USt-Id Nummer: DE268786819 Confidentiality Notice: This e-mail message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by return e-mail and destroy all copies of the original message. > -----Original Message----- > From: Greg KH [mailto:gregkh@xxxxxxxxxxxxxxxxxxx] > Sent: Mittwoch, 25. Februar 2015 16:45 > To: Schmid, Carsten > Cc: linux-usb@xxxxxxxxxxxxxxx > Subject: Re: USB driver support for high current charging > > On Wed, Feb 25, 2015 at 08:39:49AM +0000, Schmid, Carsten wrote: > > Hello, > > > > there is a spec from USB regarding high current charging (on top of USB3.0). > > Do you know if there is any driver support required, and if so, when > > will this be available with Linux? > > I think the spec will answer the "is any driver support required" > question, right? Have you looked at it? > > Do you have hardware with this feature that needs Linux support? > > thanks, > > greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
