On Fri, Sep 26, 2014 at 10:42:35AM -0400, Alan Stern wrote: > On Fri, 26 Sep 2014, Michael Grzeschik wrote: > > > The current EHCI implementation is prepared to toggle the > > PORT_POWER bit to enable or disable a USB-Port. In some > > cases this port power can not be toggled by the PORT_POWER > > bit but instead i.e. by an external GPIO. > > This patch adds an callback to be triggered as well. > > The host needs to assign a capable portpower callback. > > The idea is reasonable enough, I suppose (but where does this stop? > Before you know it, every function normally carried out by the host > controller will actually be handled by a platform-specific piece of > hardware!) I will leave this to the hardware developers and hope reality will not run down that path... :) > The implementation leaves something to be desired. Instead of keeping > the current port-power code in ehci-hcd inline, as it is, you should > define a default callback routine to do the work. Then the override > can replace the default callback. Unfortunately this does not seem to work as expected. I moved the inline codepath to the default handler. But when not changing the PORT_POWER bit in the PORTSC the chipidea core will not work even when the device is powered by the gpio regulator. Thanks, Michael -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | -- 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
