hi alan: 2014-08-29 22:54 GMT+08:00 Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>: > On Fri, 29 Aug 2014, vichy wrote: > >> hi all: >> I have read the article below and try to do the same operation on my device. >> http://lwn.net/Articles/143397/ >> >> My environment: >> 1. my kernel is 3.16 >> 2. device descriptor is attached. >> 3. below are my operation logs: >> # echo -n "4-2:1.0" > /sys/bus/usb/drivers/uas/unbind >> # echo -n "4-2:1.0" > /sys/bus/usb/drivers/usb-storage/unbind >> bash: echo: write error: No such device >> # > > Why do you want to bind your drive to usb-storage instead of uas? I read the article from the web but have no real test case to try on my pc until I found there are both usb-storage and uas interface on my external hard disk. > >> My questions: >> 1. is there anything I need to do, such as PCI driver, before bind to >> usb-storage driver? > > Normally, if uas will bind to a device then usb-storage won't. You can > change this by using a module paramter for usb-storage: > > modprobe usb-storage quirks=1759:5002:u > > (1759 and 5002 are the vendor and product IDs for this device.) Is there any interface priority written in driver to let uas instead of usb-storage bind the device? BTW, if we try not let uas bind the device, why don't we add the quirk in uas but usb-storage? What is the "u" at the end of command mean? > >> 2. I can check whether the usb device is bound to specific driver >> through "cat /sys/kernel/debug/usb/devices". >> is there any alternative way to do so? how about other drivers, >> except usb, to let user know whether the binding/unbinding >> successfully and which device is bound to which driver? > > ls -l /sys/bus/usb/devices/.../driver > > where you fill in the "..." with the path for the interface you are > interested in, such as 1-4:1.0. Alternatively, > > ls /sys/bus/usb/drivers/.../ > > where you fill in the "..." with the name of the driver you are > interested in. > I found what you mentioned ^^ appreciate your help, -- 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
