Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 70 insertions, 0 deletions

diff --git a/Documentation/hwmon/drivetemp.rst b/Documentation/hwmon/drivetemp.rst
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+.. SPDX-License-Identifier: GPL-2.0
+
+Kernel driver drivetemp
+=======================
+
+
+References
+----------
+
+ANS T13/1699-D
+Information technology - AT Attachment 8 - ATA/ATAPI Command Set (ATA8-ACS)
+
+ANS Project T10/BSR INCITS 513
+Information technology - SCSI Primary Commands - 4 (SPC-4)
+
+ANS Project INCITS 557
+Information technology - SCSI / ATA Translation - 5 (SAT-5)
+
+
+Description
+-----------
+
+This driver supports reporting the temperature of disk and solid state
+drives with temperature sensors.
+
+If supported, it uses the ATA SCT Command Transport feature to read
+the current drive temperature and, if available, temperature limits
+as well as historic minimum and maximum temperatures. If SCT Command
+Transport is not supported, the driver uses SMART attributes to read
+the drive temperature.
+
+
+Usage Note
+----------
+
+Reading the drive temperature may reset the spin down timer on some drives.
+This has been observed with WD120EFAX drives, but may be seen with other
+drives as well. The same behavior is observed if the 'hdtemp' or 'smartd'
+tools are used to access the drive.
+With the WD120EFAX drive, reading the drive temperature using the drivetemp
+driver is still possible _after_ it transitioned to standby mode, and
+reading the drive temperature in this mode will not cause the drive to
+change its mode (meaning the drive will not spin up). It is unknown if other
+drives experience similar behavior.
+
+A known workaround for WD120EFAX drives is to read the drive temperature at
+intervals larger than twice the spin-down time. Otherwise affected drives
+will never spin down.
+
+
+Sysfs entries
+-------------
+
+Only the temp1_input attribute is always available. Other attributes are
+available only if reported by the drive. All temperatures are reported in
+milli-degrees Celsius.
+
+=======================	=====================================================
+temp1_input		Current drive temperature
+temp1_lcrit		Minimum temperature limit. Operating the device below
+			this temperature may cause physical damage to the
+			device.
+temp1_min		Minimum recommended continuous operating limit
+temp1_max		Maximum recommended continuous operating temperature
+temp1_crit		Maximum temperature limit. Operating the device above
+			this temperature may cause physical damage to the
+			device.
+temp1_lowest		Minimum temperature seen this power cycle
+temp1_highest		Maximum temperature seen this power cycle
+=======================	=====================================================