1*4882a593SmuzhiyunWhat: /sys/block/*/device/sw_activity 2*4882a593SmuzhiyunDate: Jun, 2008 3*4882a593SmuzhiyunKernelVersion: v2.6.27 4*4882a593SmuzhiyunContact: linux-ide@vger.kernel.org 5*4882a593SmuzhiyunDescription: 6*4882a593Smuzhiyun (RW) Used by drivers which support software controlled activity 7*4882a593Smuzhiyun LEDs. 8*4882a593Smuzhiyun 9*4882a593Smuzhiyun It has the following valid values: 10*4882a593Smuzhiyun 11*4882a593Smuzhiyun == ======================================================== 12*4882a593Smuzhiyun 0 OFF - the LED is not activated on activity 13*4882a593Smuzhiyun 1 BLINK_ON - the LED blinks on every 10ms when activity is 14*4882a593Smuzhiyun detected. 15*4882a593Smuzhiyun 2 BLINK_OFF - the LED is on when idle, and blinks off 16*4882a593Smuzhiyun every 10ms when activity is detected. 17*4882a593Smuzhiyun == ======================================================== 18*4882a593Smuzhiyun 19*4882a593Smuzhiyun Note that the user must turn sw_activity OFF it they wish to 20*4882a593Smuzhiyun control the activity LED via the em_message file. 21*4882a593Smuzhiyun 22*4882a593Smuzhiyun 23*4882a593SmuzhiyunWhat: /sys/block/*/device/unload_heads 24*4882a593SmuzhiyunDate: Sep, 2008 25*4882a593SmuzhiyunKernelVersion: v2.6.28 26*4882a593SmuzhiyunContact: linux-ide@vger.kernel.org 27*4882a593SmuzhiyunDescription: 28*4882a593Smuzhiyun (RW) Hard disk shock protection 29*4882a593Smuzhiyun 30*4882a593Smuzhiyun Writing an integer value to this file will take the heads of the 31*4882a593Smuzhiyun respective drive off the platter and block all I/O operations 32*4882a593Smuzhiyun for the specified number of milliseconds. 33*4882a593Smuzhiyun 34*4882a593Smuzhiyun - If the device does not support the unload heads feature, 35*4882a593Smuzhiyun access is denied with -EOPNOTSUPP. 36*4882a593Smuzhiyun - The maximal value accepted for a timeout is 30000 37*4882a593Smuzhiyun milliseconds. 38*4882a593Smuzhiyun - A previously set timeout can be cancelled and disk can resume 39*4882a593Smuzhiyun normal operation immediately by specifying a timeout of 0. 40*4882a593Smuzhiyun - Some hard drives only comply with an earlier version of the 41*4882a593Smuzhiyun ATA standard, but support the unload feature nonetheless. 42*4882a593Smuzhiyun There is no safe way Linux can detect these devices, so this 43*4882a593Smuzhiyun is not enabled by default. If it is known that your device 44*4882a593Smuzhiyun does support the unload feature, then you can tell the kernel 45*4882a593Smuzhiyun to enable it by writing -1. It can be disabled again by 46*4882a593Smuzhiyun writing -2. 47*4882a593Smuzhiyun - Values below -2 are rejected with -EINVAL 48*4882a593Smuzhiyun 49*4882a593Smuzhiyun For more information, see 50*4882a593Smuzhiyun Documentation/admin-guide/laptops/disk-shock-protection.rst 51*4882a593Smuzhiyun 52*4882a593Smuzhiyun 53*4882a593SmuzhiyunWhat: /sys/block/*/device/ncq_prio_enable 54*4882a593SmuzhiyunDate: Oct, 2016 55*4882a593SmuzhiyunKernelVersion: v4.10 56*4882a593SmuzhiyunContact: linux-ide@vger.kernel.org 57*4882a593SmuzhiyunDescription: 58*4882a593Smuzhiyun (RW) Write to the file to turn on or off the SATA ncq (native 59*4882a593Smuzhiyun command queueing) support. By default this feature is turned 60*4882a593Smuzhiyun off. 61