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diff --git a/Documentation/hwmon/smsc47b397.rst b/Documentation/hwmon/smsc47b397.rst new file mode 100644 index 000000000000..600194cf1804 --- /dev/null +++ b/Documentation/hwmon/smsc47b397.rst @@ -0,0 +1,197 @@ +Kernel driver smsc47b397 +======================== + +Supported chips: + + * SMSC LPC47B397-NC + + * SMSC SCH5307-NS + + * SMSC SCH5317 + + Prefix: 'smsc47b397' + + Addresses scanned: none, address read from Super I/O config space + + Datasheet: In this file + +Authors: + + - Mark M. Hoffman <mhoffman@lightlink.com> + - Utilitek Systems, Inc. + +November 23, 2004 + +The following specification describes the SMSC LPC47B397-NC [1]_ sensor chip +(for which there is no public datasheet available). This document was +provided by Craig Kelly (In-Store Broadcast Network) and edited/corrected +by Mark M. Hoffman <mhoffman@lightlink.com>. + +.. [1] And SMSC SCH5307-NS and SCH5317, which have different device IDs but are + otherwise compatible. + +------------------------------------------------------------------------- + +Methods for detecting the HP SIO and reading the thermal data on a dc7100 +------------------------------------------------------------------------- + +The thermal information on the dc7100 is contained in the SIO Hardware Monitor +(HWM). The information is accessed through an index/data pair. The index/data +pair is located at the HWM Base Address + 0 and the HWM Base Address + 1. The +HWM Base address can be obtained from Logical Device 8, registers 0x60 (MSB) +and 0x61 (LSB). Currently we are using 0x480 for the HWM Base Address and +0x480 and 0x481 for the index/data pair. + +Reading temperature information. +The temperature information is located in the following registers: + +=============== ======= ======================================================= +Temp1 0x25 (Currently, this reflects the CPU temp on all systems). +Temp2 0x26 +Temp3 0x27 +Temp4 0x80 +=============== ======= ======================================================= + +Programming Example +The following is an example of how to read the HWM temperature registers:: + + MOV DX,480H + MOV AX,25H + OUT DX,AL + MOV DX,481H + IN AL,DX + +AL contains the data in hex, the temperature in Celsius is the decimal +equivalent. + +Ex: If AL contains 0x2A, the temperature is 42 degrees C. + +Reading tach information. +The fan speed information is located in the following registers: + +=============== ======= ======= ================================= + LSB MSB +Tach1 0x28 0x29 (Currently, this reflects the CPU + fan speed on all systems). +Tach2 0x2A 0x2B +Tach3 0x2C 0x2D +Tach4 0x2E 0x2F +=============== ======= ======= ================================= + +.. Important:: + + Reading the tach LSB locks the tach MSB. + The LSB Must be read first. + +How to convert the tach reading to RPM +-------------------------------------- + +The tach reading (TCount) is given by: (Tach MSB * 256) + (Tach LSB) +The SIO counts the number of 90kHz (11.111us) pulses per revolution. +RPM = 60/(TCount * 11.111us) + +Example:: + + Reg 0x28 = 0x9B + Reg 0x29 = 0x08 + +TCount = 0x89B = 2203 + +RPM = 60 / (2203 * 11.11111 E-6) = 2451 RPM + +Obtaining the SIO version. + +Configuration Sequence +---------------------- + +To program the configuration registers, the following sequence must be followed: +1. Enter Configuration Mode +2. Configure the Configuration Registers +3. Exit Configuration Mode. + +Enter Configuration Mode +^^^^^^^^^^^^^^^^^^^^^^^^ + +To place the chip into the Configuration State The config key (0x55) is written +to the CONFIG PORT (0x2E). + +Configuration Mode +^^^^^^^^^^^^^^^^^^ + +In configuration mode, the INDEX PORT is located at the CONFIG PORT address and +the DATA PORT is at INDEX PORT address + 1. + +The desired configuration registers are accessed in two steps: + +a. Write the index of the Logical Device Number Configuration Register + (i.e., 0x07) to the INDEX PORT and then write the number of the + desired logical device to the DATA PORT. + +b. Write the address of the desired configuration register within the + logical device to the INDEX PORT and then write or read the config- + uration register through the DATA PORT. + +Note: + If accessing the Global Configuration Registers, step (a) is not required. + +Exit Configuration Mode +^^^^^^^^^^^^^^^^^^^^^^^ + +To exit the Configuration State the write 0xAA to the CONFIG PORT (0x2E). +The chip returns to the RUN State. (This is important). + +Programming Example +^^^^^^^^^^^^^^^^^^^ + +The following is an example of how to read the SIO Device ID located at 0x20: + + ; ENTER CONFIGURATION MODE + MOV DX,02EH + MOV AX,055H + OUT DX,AL + ; GLOBAL CONFIGURATION REGISTER + MOV DX,02EH + MOV AL,20H + OUT DX,AL + ; READ THE DATA + MOV DX,02FH + IN AL,DX + ; EXIT CONFIGURATION MODE + MOV DX,02EH + MOV AX,0AAH + OUT DX,AL + +The registers of interest for identifying the SIO on the dc7100 are Device ID +(0x20) and Device Rev (0x21). + +The Device ID will read 0x6F (0x81 for SCH5307-NS, and 0x85 for SCH5317) +The Device Rev currently reads 0x01 + +Obtaining the HWM Base Address +------------------------------ + +The following is an example of how to read the HWM Base Address located in +Logical Device 8:: + + ; ENTER CONFIGURATION MODE + MOV DX,02EH + MOV AX,055H + OUT DX,AL + ; CONFIGURE REGISTER CRE0, + ; LOGICAL DEVICE 8 + MOV DX,02EH + MOV AL,07H + OUT DX,AL ;Point to LD# Config Reg + MOV DX,02FH + MOV AL, 08H + OUT DX,AL;Point to Logical Device 8 + ; + MOV DX,02EH + MOV AL,60H + OUT DX,AL ; Point to HWM Base Addr MSB + MOV DX,02FH + IN AL,DX ; Get MSB of HWM Base Addr + ; EXIT CONFIGURATION MODE + MOV DX,02EH + MOV AX,0AAH + OUT DX,AL |