On Mon, 24 Nov 2014, tianjulin wrote: > Hi Stern, > > 1:Thanks your kind support,but how to turn off media-change polling? echo -1 >/sys/block/sdX/events_poll_msecs Replace the X with the drive letter for your card reader. > or > may I change the polling time for long time to fixed this bug? Yes. Replace the -1 above with the polling time, in milliseconds. > 2:If media-change polling prevent the device entering runtime suspend, > Why connect USB storage devices without operator and usb mouse also may > cause USB bus can't enter runtime suspend? You have to enable runtime suspend for the devices. By default, runtime suspend is disabled. You can enable runtime suspend by writing "auto" into the device's power/control sysfs file. You may also want to write an appropriate delay value into the device's power/autosuspend_delay_ms sysfs file. > 3:I have check my source code,as follows commit have include in my > kernel version. > > 66311274691e > 6c9546675864 > c8158819d506 > 9b21493c4520 > 6df339a51e3b > d20ec597cba1 > c60855cdb976 > 10c580e4239d > > 4:I have try several of kind devices (usb mouse,usb > storage,usb-card,etc)on usb bus ,all of them may cause usb bus can't > enter runtime suspend. The bus won't enter runtime suspend until all of the devices attached to the bus are in runtime suspend. > *5:When I insert a sdcard into sdcard-read,the usb bus still can't enter > runtime suspend.* Alan Stern -- 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
