i2cdetect: Clarify the SMBus commands used for probing by default.

git-svn-id: http://lm-sensors.org/svn/i2c-tools/branches/i2c-tools-3.1@6110 7894878c-1315-0410-8ee3-d5d059ff63e0

CHANGES

@@ -8,6 +8,7 @@ SVN HEAD
                 Update manufacturer IDs
                 Remove duplicate "ns" in SDR timings
                 Fix decoding of SDR SPD revision
+  i2cdetect: Clarify the SMBus commands used for probing by default
   i2c-dev.h: Minimize differences with kernel flavor
              Move SMBus helper functions to include/i2c/smbus.h
   i2c-stub-from-dump: Be more tolerant on input dump format

tools/i2cdetect.8

@@ -28,6 +28,12 @@ should correspond to one of the busses listed by \fIi2cdetect -l\fR.
 The optional parameters \fIfirst\fR and \fIlast\fR restrict the scanning
 range (default: from 0x03 to 0x77).
 .PP
+As there is no standard I2C detection command, i2cdetect uses arbitrary
+SMBus commands (namely SMBus quick write and SMBus receive byte) to probe
+for devices. By default, the command used is the one believed to be the
+safest for each address. See options \fI-q\fR and \fI-r\fR to change this
+behavior.
+.PP
 i2cdetect can also be used to query the functionalities of an I2C bus
 (see option \fB-F\fP.)
 
@@ -57,14 +63,12 @@ scripts.
 Force scanning of non-regular addresses. Not recommended.
 .TP
 .B "\-q"
-Use SMBus "quick write" commands for probing (by default, the command
-used is the one believed to be the safest for each address). 
+Use SMBus "quick write" command for probing.
 Not recommended. This is known to corrupt the Atmel AT24RF08 EEPROM
 found on many IBM Thinkpad laptops.
 .TP
 .B "\-r"
-Use SMBus "read byte" commands for probing (by default, the command
-used is the one believed to be the safest for each address). 
+Use SMBus "receive byte" command for probing.
 Not recommended. This is known to lock SMBus on various write-only
 chips (most notably clock chips at address 0x69).
 .TP