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-rw-r--r--Documentation/i2c/chips/max68752
-rw-r--r--Documentation/i2c/chips/pca953910
-rw-r--r--Documentation/i2c/chips/pcf857412
-rw-r--r--Documentation/i2c/chips/pcf85759
4 files changed, 18 insertions, 15 deletions
diff --git a/Documentation/i2c/chips/max6875 b/Documentation/i2c/chips/max6875
index a0cd8af..10ca43c 100644
--- a/Documentation/i2c/chips/max6875
+++ b/Documentation/i2c/chips/max6875
@@ -49,7 +49,7 @@ $ modprobe max6875 force=0,0x50
The MAX6874/MAX6875 ignores address bit 0, so this driver attaches to multiple
addresses. For example, for address 0x50, it also reserves 0x51.
-The even-address instance is called 'max6875', the odd one is 'max6875 subclient'.
+The even-address instance is called 'max6875', the odd one is 'dummy'.
Programming the chip using i2c-dev
diff --git a/Documentation/i2c/chips/pca9539 b/Documentation/i2c/chips/pca9539
index 1d81c53..6aff890 100644
--- a/Documentation/i2c/chips/pca9539
+++ b/Documentation/i2c/chips/pca9539
@@ -7,7 +7,7 @@ drivers/gpio/pca9539.c instead.
Supported chips:
* Philips PCA9539
Prefix: 'pca9539'
- Addresses scanned: 0x74 - 0x77
+ Addresses scanned: none
Datasheet:
http://www.semiconductors.philips.com/acrobat/datasheets/PCA9539_2.pdf
@@ -23,6 +23,14 @@ The input sense can also be inverted.
The 16 lines are split between two bytes.
+Detection
+---------
+
+The PCA9539 is difficult to detect and not commonly found in PC machines,
+so you have to pass the I2C bus and address of the installed PCA9539
+devices explicitly to the driver at load time via the force=... parameter.
+
+
Sysfs entries
-------------
diff --git a/Documentation/i2c/chips/pcf8574 b/Documentation/i2c/chips/pcf8574
index 5c1ad13..235815c 100644
--- a/Documentation/i2c/chips/pcf8574
+++ b/Documentation/i2c/chips/pcf8574
@@ -4,13 +4,13 @@ Kernel driver pcf8574
Supported chips:
* Philips PCF8574
Prefix: 'pcf8574'
- Addresses scanned: I2C 0x20 - 0x27
+ Addresses scanned: none
Datasheet: Publicly available at the Philips Semiconductors website
http://www.semiconductors.philips.com/pip/PCF8574P.html
* Philips PCF8574A
Prefix: 'pcf8574a'
- Addresses scanned: I2C 0x38 - 0x3f
+ Addresses scanned: none
Datasheet: Publicly available at the Philips Semiconductors website
http://www.semiconductors.philips.com/pip/PCF8574P.html
@@ -38,12 +38,10 @@ For more informations see the datasheet.
Accessing PCF8574(A) via /sys interface
-------------------------------------
-! Be careful !
The PCF8574(A) is plainly impossible to detect ! Stupid chip.
-So every chip with address in the interval [20..27] and [38..3f] are
-detected as PCF8574(A). If you have other chips in this address
-range, the workaround is to load this module after the one
-for your others chips.
+So, you have to pass the I2C bus and address of the installed PCF857A
+and PCF8574A devices explicitly to the driver at load time via the
+force=... parameter.
On detection (i.e. insmod, modprobe et al.), directories are being
created for each detected PCF8574(A):
diff --git a/Documentation/i2c/chips/pcf8575 b/Documentation/i2c/chips/pcf8575
index 25f5698..40b268e 100644
--- a/Documentation/i2c/chips/pcf8575
+++ b/Documentation/i2c/chips/pcf8575
@@ -40,12 +40,9 @@ Detection
---------
There is no method known to detect whether a chip on a given I2C address is
-a PCF8575 or whether it is any other I2C device. So there are two alternatives
-to let the driver find the installed PCF8575 devices:
-- Load this driver after any other I2C driver for I2C devices with addresses
- in the range 0x20 .. 0x27.
-- Pass the I2C bus and address of the installed PCF8575 devices explicitly to
- the driver at load time via the probe=... or force=... parameters.
+a PCF8575 or whether it is any other I2C device, so you have to pass the I2C
+bus and address of the installed PCF8575 devices explicitly to the driver at
+load time via the force=... parameter.
/sys interface
--------------
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