On Thu, 8 Nov 2012, Sergei Shtylyov wrote: > >> USB specs says that if an over-current is detected then a hub must switch > >> off > >> all affected port, wait to cool down and then switch on. > > >> There are few controllers, which does not follow it, and expects software > >> to switch off the port power. > > > Can you give any examples? > > The example that springs to my mind is EHCI -- but the EHCI driver takes > care > for switching the port off.
Which EHCI implementation are you talking about? And where does the EHCI driver switch ports off when they encounter an overcurrent condition? The EHCI controllers I have used do not allow software to control the port power levels at all. It's all done in hardware. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
