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authorLinus Torvalds <torvalds@linux-foundation.org>2021-07-05 13:42:16 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-07-05 13:42:16 -0700
commiteed0218e8cae9fcd186c30e9fcf5fe46a87e056e (patch)
tree799a1360b947a56d05a60433fdf60a96bf3b3348 /Documentation/w1
parent3f8b8e7dbd79086ad48fcff33de9399f3da66a69 (diff)
parent6f746d485fb9188dc67dce7de63d21f0c28a1f2e (diff)
Merge tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char / misc driver updates from Greg KH: "Here is the big set of char / misc and other driver subsystem updates for 5.14-rc1. Included in here are: - habanalabs driver updates - fsl-mc driver updates - comedi driver updates - fpga driver updates - extcon driver updates - interconnect driver updates - mei driver updates - nvmem driver updates - phy driver updates - pnp driver updates - soundwire driver updates - lots of other tiny driver updates for char and misc drivers This is looking more and more like the "various driver subsystems mushed together" tree... All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits) mcb: Use DEFINE_RES_MEM() helper macro and fix the end address PNP: moved EXPORT_SYMBOL so that it immediately followed its function/variable bus: mhi: pci-generic: Add missing 'pci_disable_pcie_error_reporting()' calls bus: mhi: Wait for M2 state during system resume bus: mhi: core: Fix power down latency intel_th: Wait until port is in reset before programming it intel_th: msu: Make contiguous buffers uncached intel_th: Remove an unused exit point from intel_th_remove() stm class: Spelling fix nitro_enclaves: Set Bus Master for the NE PCI device misc: ibmasm: Modify matricies to matrices misc: vmw_vmci: return the correct errno code siox: Simplify error handling via dev_err_probe() fpga: machxo2-spi: Address warning about unused variable lkdtm/heap: Add init_on_alloc tests selftests/lkdtm: Enable various testable CONFIGs lkdtm: Add CONFIG hints in errors where possible lkdtm: Enable DOUBLE_FAULT on all architectures lkdtm/heap: Add vmalloc linear overflow test lkdtm/bugs: XFAIL UNALIGNED_LOAD_STORE_WRITE ...
Diffstat (limited to 'Documentation/w1')
-rw-r--r--Documentation/w1/slaves/w1_ds2438.rst19
1 files changed, 18 insertions, 1 deletions
diff --git a/Documentation/w1/slaves/w1_ds2438.rst b/Documentation/w1/slaves/w1_ds2438.rst
index a29309a3f8e5..4fa671fbc93f 100644
--- a/Documentation/w1/slaves/w1_ds2438.rst
+++ b/Documentation/w1/slaves/w1_ds2438.rst
@@ -22,7 +22,7 @@ is also often used in weather stations and applications such as: rain gauge,
wind speed/direction measuring, humidity sensing, etc.
Current support is provided through the following sysfs files (all files
-except "iad" are readonly):
+except "iad" and "offset" are readonly):
"iad"
-----
@@ -44,6 +44,23 @@ Internally when this file is read, the additional CRC byte is also obtained
from the slave device. If it is correct, the 8 bytes page data are passed
to userspace, otherwise an I/O error is returned.
+"page1"
+-------
+This file provides full 8 bytes of the chip Page 1 (01h).
+This page contains the ICA, elapsed time meter and current offset data of the DS2438.
+Internally when this file is read, the additional CRC byte is also obtained
+from the slave device. If it is correct, the 8 bytes page data are passed
+to userspace, otherwise an I/O error is returned.
+
+"offset"
+--------
+This file controls the 2-byte Offset Register of the chip.
+Writing a 2-byte value will change the Offset Register, which changes the
+current measurement done by the chip. Changing this register to the two's complement
+of the current register while forcing zero current through the load will calibrate
+the chip, canceling offset errors in the current ADC.
+
+
"temperature"
-------------
Opening and reading this file initiates the CONVERT_T (temperature conversion)