10a65e125SAishwarya PantWhat: /sys/block/*/device/sw_activity 20a65e125SAishwarya PantDate: Jun, 2008 30a65e125SAishwarya PantKernelVersion: v2.6.27 40a65e125SAishwarya PantContact: linux-ide@vger.kernel.org 50a65e125SAishwarya PantDescription: 60a65e125SAishwarya Pant (RW) Used by drivers which support software controlled activity 70a65e125SAishwarya Pant LEDs. 80a65e125SAishwarya Pant 90a65e125SAishwarya Pant It has the following valid values: 100a65e125SAishwarya Pant 1134433332SMauro Carvalho Chehab == ======================================================== 120a65e125SAishwarya Pant 0 OFF - the LED is not activated on activity 130a65e125SAishwarya Pant 1 BLINK_ON - the LED blinks on every 10ms when activity is 140a65e125SAishwarya Pant detected. 150a65e125SAishwarya Pant 2 BLINK_OFF - the LED is on when idle, and blinks off 160a65e125SAishwarya Pant every 10ms when activity is detected. 1734433332SMauro Carvalho Chehab == ======================================================== 180a65e125SAishwarya Pant 190a65e125SAishwarya Pant Note that the user must turn sw_activity OFF it they wish to 200a65e125SAishwarya Pant control the activity LED via the em_message file. 210a65e125SAishwarya Pant 220a65e125SAishwarya Pant 230a65e125SAishwarya PantWhat: /sys/block/*/device/unload_heads 240a65e125SAishwarya PantDate: Sep, 2008 250a65e125SAishwarya PantKernelVersion: v2.6.28 260a65e125SAishwarya PantContact: linux-ide@vger.kernel.org 270a65e125SAishwarya PantDescription: 280a65e125SAishwarya Pant (RW) Hard disk shock protection 290a65e125SAishwarya Pant 300a65e125SAishwarya Pant Writing an integer value to this file will take the heads of the 310a65e125SAishwarya Pant respective drive off the platter and block all I/O operations 320a65e125SAishwarya Pant for the specified number of milliseconds. 330a65e125SAishwarya Pant 340a65e125SAishwarya Pant - If the device does not support the unload heads feature, 350a65e125SAishwarya Pant access is denied with -EOPNOTSUPP. 360a65e125SAishwarya Pant - The maximal value accepted for a timeout is 30000 370a65e125SAishwarya Pant milliseconds. 380a65e125SAishwarya Pant - A previously set timeout can be cancelled and disk can resume 390a65e125SAishwarya Pant normal operation immediately by specifying a timeout of 0. 400a65e125SAishwarya Pant - Some hard drives only comply with an earlier version of the 410a65e125SAishwarya Pant ATA standard, but support the unload feature nonetheless. 420a65e125SAishwarya Pant There is no safe way Linux can detect these devices, so this 430a65e125SAishwarya Pant is not enabled by default. If it is known that your device 440a65e125SAishwarya Pant does support the unload feature, then you can tell the kernel 450a65e125SAishwarya Pant to enable it by writing -1. It can be disabled again by 460a65e125SAishwarya Pant writing -2. 470a65e125SAishwarya Pant - Values below -2 are rejected with -EINVAL 480a65e125SAishwarya Pant 490a65e125SAishwarya Pant For more information, see 509e1cbedeSMauro Carvalho Chehab Documentation/admin-guide/laptops/disk-shock-protection.rst 510a65e125SAishwarya Pant 520a65e125SAishwarya Pant 530a65e125SAishwarya PantWhat: /sys/block/*/device/ncq_prio_enable 540a65e125SAishwarya PantDate: Oct, 2016 550a65e125SAishwarya PantKernelVersion: v4.10 560a65e125SAishwarya PantContact: linux-ide@vger.kernel.org 570a65e125SAishwarya PantDescription: 585b8a2345SNiklas Cassel (RW) Write to the file to turn on or off the SATA NCQ (native 595b8a2345SNiklas Cassel command queueing) priority support. By default this feature is 605b8a2345SNiklas Cassel turned off. If the device does not support the SATA NCQ 61f5975d18SDamien Le Moal priority feature, writing "1" to this file results in an error 62f5975d18SDamien Le Moal (see ncq_prio_supported). 635b8a2345SNiklas Cassel 645b8a2345SNiklas Cassel 655b8a2345SNiklas CasselWhat: /sys/block/*/device/sas_ncq_prio_enable 665b8a2345SNiklas CasselDate: Oct, 2016 675b8a2345SNiklas CasselKernelVersion: v4.10 685b8a2345SNiklas CasselContact: linux-ide@vger.kernel.org 695b8a2345SNiklas CasselDescription: 705b8a2345SNiklas Cassel (RW) This is the equivalent of the ncq_prio_enable attribute 715b8a2345SNiklas Cassel file for SATA devices connected to a SAS host-bus-adapter 725b8a2345SNiklas Cassel (HBA) implementing support for the SATA NCQ priority feature. 735b8a2345SNiklas Cassel This file does not exist if the HBA driver does not implement 745b8a2345SNiklas Cassel support for the SATA NCQ priority feature, regardless of the 75f5975d18SDamien Le Moal device support for this feature (see sas_ncq_prio_supported). 76f5975d18SDamien Le Moal 77f5975d18SDamien Le Moal 78f5975d18SDamien Le MoalWhat: /sys/block/*/device/ncq_prio_supported 79f5975d18SDamien Le MoalDate: Aug, 2021 80f5975d18SDamien Le MoalKernelVersion: v5.15 81f5975d18SDamien Le MoalContact: linux-ide@vger.kernel.org 82f5975d18SDamien Le MoalDescription: 83f5975d18SDamien Le Moal (RO) Indicates if the device supports the SATA NCQ (native 84f5975d18SDamien Le Moal command queueing) priority feature. 85f5975d18SDamien Le Moal 86f5975d18SDamien Le Moal 87f5975d18SDamien Le MoalWhat: /sys/block/*/device/sas_ncq_prio_supported 88f5975d18SDamien Le MoalDate: Aug, 2021 89f5975d18SDamien Le MoalKernelVersion: v5.15 90f5975d18SDamien Le MoalContact: linux-ide@vger.kernel.org 91f5975d18SDamien Le MoalDescription: 92f5975d18SDamien Le Moal (RO) This is the equivalent of the ncq_prio_supported attribute 93f5975d18SDamien Le Moal file for SATA devices connected to a SAS host-bus-adapter 94f5975d18SDamien Le Moal (HBA) implementing support for the SATA NCQ priority feature. 95f5975d18SDamien Le Moal This file does not exist if the HBA driver does not implement 96f5975d18SDamien Le Moal support for the SATA NCQ priority feature, regardless of the 975b8a2345SNiklas Cassel device support for this feature. 9862488520SDamien Le Moal 9962488520SDamien Le Moal 10062488520SDamien Le MoalWhat: /sys/block/*/device/cdl_supported 10162488520SDamien Le MoalDate: May, 2023 10262488520SDamien Le MoalKernelVersion: v6.5 10362488520SDamien Le MoalContact: linux-scsi@vger.kernel.org 10462488520SDamien Le MoalDescription: 10562488520SDamien Le Moal (RO) Indicates if the device supports the command duration 10662488520SDamien Le Moal limits feature found in some ATA and SCSI devices. 107*1b22cfb1SDamien Le Moal 108*1b22cfb1SDamien Le Moal 109*1b22cfb1SDamien Le MoalWhat: /sys/block/*/device/cdl_enable 110*1b22cfb1SDamien Le MoalDate: May, 2023 111*1b22cfb1SDamien Le MoalKernelVersion: v6.5 112*1b22cfb1SDamien Le MoalContact: linux-scsi@vger.kernel.org 113*1b22cfb1SDamien Le MoalDescription: 114*1b22cfb1SDamien Le Moal (RW) For a device supporting the command duration limits 115*1b22cfb1SDamien Le Moal feature, write to the file to turn on or off the feature. 116*1b22cfb1SDamien Le Moal By default this feature is turned off. 117*1b22cfb1SDamien Le Moal Writing "1" to this file enables the use of command duration 118*1b22cfb1SDamien Le Moal limits for read and write commands in the kernel and turns on 119*1b22cfb1SDamien Le Moal the feature on the device. Writing "0" disables the feature. 120