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| author | Ingo Molnar <mingo@kernel.org> | 2019-05-16 10:04:48 +0300 |
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| committer | Ingo Molnar <mingo@kernel.org> | 2019-05-16 10:04:48 +0300 |
| commit | 00f5764dbb040188e5dce2cd9e648360886b045c (patch) | |
| tree | 2dc969bb165a27a7cebdd1798b7a697243a790de /Documentation/hwmon/lm70.rst | |
| parent | 409ca45526a428620d8efb362ccfd4b1e6b80642 (diff) | |
| parent | 5ac94332248ee017964ba368cdda4ce647e3aba7 (diff) | |
| download | linux-00f5764dbb040188e5dce2cd9e648360886b045c.tar.xz | |
Merge branch 'linus' into x86/urgent, to pick up dependent changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'Documentation/hwmon/lm70.rst')
| -rw-r--r-- | Documentation/hwmon/lm70.rst | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/Documentation/hwmon/lm70.rst b/Documentation/hwmon/lm70.rst new file mode 100644 index 000000000000..f259bc1fcd91 --- /dev/null +++ b/Documentation/hwmon/lm70.rst @@ -0,0 +1,62 @@ +Kernel driver lm70 +================== + +Supported chips: + + * National Semiconductor LM70 + + Datasheet: http://www.national.com/pf/LM/LM70.html + + * Texas Instruments TMP121/TMP123 + + Information: http://focus.ti.com/docs/prod/folders/print/tmp121.html + + * Texas Instruments TMP122/TMP124 + + Information: http://www.ti.com/product/tmp122 + + * National Semiconductor LM71 + + Datasheet: http://www.ti.com/product/LM71 + + * National Semiconductor LM74 + + Datasheet: http://www.ti.com/product/LM74 + + +Author: + Kaiwan N Billimoria <kaiwan@designergraphix.com> + +Description +----------- + +This driver implements support for the National Semiconductor LM70 +temperature sensor. + +The LM70 temperature sensor chip supports a single temperature sensor. +It communicates with a host processor (or microcontroller) via an +SPI/Microwire Bus interface. + +Communication with the LM70 is simple: when the temperature is to be sensed, +the driver accesses the LM70 using SPI communication: 16 SCLK cycles +comprise the MOSI/MISO loop. At the end of the transfer, the 11-bit 2's +complement digital temperature (sent via the SIO line), is available in the +driver for interpretation. This driver makes use of the kernel's in-core +SPI support. + +As a real (in-tree) example of this "SPI protocol driver" interfacing +with a "SPI master controller driver", see drivers/spi/spi_lm70llp.c +and its associated documentation. + +The LM74 and TMP121/TMP122/TMP123/TMP124 are very similar; main difference is +13-bit temperature data (0.0625 degrees celsius resolution). + +The TMP122/TMP124 also feature configurable temperature thresholds. + +The LM71 is also very similar; main difference is 14-bit temperature +data (0.03125 degrees celsius resolution). + +Thanks to +--------- +Jean Delvare <jdelvare@suse.de> for mentoring the hwmon-side driver +development. |