On Sun, Jun 16, 2013 at 04:19:23PM -0400, George Spelvin wrote: > So I'm compiling 3.10-rc, and I am presented with a new config option: > > menuconfig USB_PHY > tristate "USB Physical Layer drivers" > select USB_OTG_UTILS > help > USB controllers (those which are host, device or DRD) need a > device to handle the physical layer signalling, commonly called > a PHY. > > The following drivers add support for such PHY devices. > > Okay, so I have a PC motherboard with a large number of host USB > controllers. This tells me those controllers need a PHY, and > at least once of the following drivers is needed to support that > PHY. > > But which one? I have an Intel X79 chipset, and "Intel" doesn't > appear anywhere in the Kconfig file. It's all Freescale, Philips/NXP, > Marvell, Qualcomm, TI OMAP, Samsung, Renesas, etc. > > The only ICs by any of those on my motherboard are some Marvell > SATA controllers. > > > Anyway, I searched my old working .config and I didn't have any such > drivers enabled. So I turned off this option, compiled and rebooted, > kept my fingers crossed, and... yay! Keyboard still works! > > Thumb drive still works, USB/SATA adapter still works... I don't know > WTF is going on here, but it looks like that help text lied to me. > > Could someone please rephrase it to reflect the truth better? > > How about (I'm not sure if this is *correct*, but consider it > Signed-off-By if you want to use it): > > USB controllers (those which are host, peripheral or DRD) need > a device to handle the physical layer signalling, commonly > called a PHY. > > Standard x86 motherboards combine the PHY with the controller > and do not need a separate driver, but some systems-on-chip > use a separate PHY. This is particularly true for dual-role > (a.k.a. USB on-the-go) devices. > > The drivers in this submenu add support for such PHY devices. > > If you're not sure if this applies to you, it probably doesn't; > say N here. Feel free to rewrite this as a patch, in the proper form, so that I can apply it, I like it much better than what we have now. 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
