summaryrefslogtreecommitdiffstats
path: root/Documentation/i2c/chips
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/i2c/chips')
-rw-r--r--Documentation/i2c/chips/pca953958
-rw-r--r--Documentation/i2c/chips/pcf857465
-rw-r--r--Documentation/i2c/chips/pcf857569
3 files changed, 0 insertions, 192 deletions
diff --git a/Documentation/i2c/chips/pca9539 b/Documentation/i2c/chips/pca9539
deleted file mode 100644
index 6aff890088b1..000000000000
--- a/Documentation/i2c/chips/pca9539
+++ /dev/null
@@ -1,58 +0,0 @@
-Kernel driver pca9539
-=====================
-
-NOTE: this driver is deprecated and will be dropped soon, use
-drivers/gpio/pca9539.c instead.
-
-Supported chips:
- * Philips PCA9539
- Prefix: 'pca9539'
- Addresses scanned: none
- Datasheet:
- http://www.semiconductors.philips.com/acrobat/datasheets/PCA9539_2.pdf
-
-Author: Ben Gardner <bgardner@wabtec.com>
-
-
-Description
------------
-
-The Philips PCA9539 is a 16 bit low power I/O device.
-All 16 lines can be individually configured as an input or output.
-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
--------------
-
-Each is a byte that maps to the 8 I/O bits.
-A '0' suffix is for bits 0-7, while '1' is for bits 8-15.
-
-input[01] - read the current value
-output[01] - sets the output value
-direction[01] - direction of each bit: 1=input, 0=output
-invert[01] - toggle the input bit sense
-
-input reads the actual state of the line and is always available.
-The direction defaults to input for all channels.
-
-
-General Remarks
----------------
-
-Note that each output, direction, and invert entry controls 8 lines.
-You should use the read, modify, write sequence.
-For example. to set output bit 0 of 1.
- val=$(cat output0)
- val=$(( $val | 1 ))
- echo $val > output0
-
diff --git a/Documentation/i2c/chips/pcf8574 b/Documentation/i2c/chips/pcf8574
deleted file mode 100644
index 235815c075ff..000000000000
--- a/Documentation/i2c/chips/pcf8574
+++ /dev/null
@@ -1,65 +0,0 @@
-Kernel driver pcf8574
-=====================
-
-Supported chips:
- * Philips PCF8574
- Prefix: 'pcf8574'
- 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: none
- Datasheet: Publicly available at the Philips Semiconductors website
- http://www.semiconductors.philips.com/pip/PCF8574P.html
-
-Authors:
- Frodo Looijaard <frodol@dds.nl>,
- Philip Edelbrock <phil@netroedge.com>,
- Dan Eaton <dan.eaton@rocketlogix.com>,
- Aurelien Jarno <aurelien@aurel32.net>,
- Jean Delvare <khali@linux-fr.org>,
-
-
-Description
------------
-The PCF8574(A) is an 8-bit I/O expander for the I2C bus produced by Philips
-Semiconductors. It is designed to provide a byte I2C interface to up to 16
-separate devices (8 x PCF8574 and 8 x PCF8574A).
-
-This device consists of a quasi-bidirectional port. Each of the eight I/Os
-can be independently used as an input or output. To setup an I/O as an
-input, you have to write a 1 to the corresponding output.
-
-For more informations see the datasheet.
-
-
-Accessing PCF8574(A) via /sys interface
--------------------------------------
-
-The PCF8574(A) is plainly impossible to detect ! Stupid chip.
-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):
-
-/sys/bus/i2c/devices/<0>-<1>/
-where <0> is the bus the chip was detected on (e. g. i2c-0)
-and <1> the chip address ([20..27] or [38..3f]):
-
-(example: /sys/bus/i2c/devices/1-0020/)
-
-Inside these directories, there are two files each:
-read and write (and one file with chip name).
-
-The read file is read-only. Reading gives you the current I/O input
-if the corresponding output is set as 1, otherwise the current output
-value, that is to say 0.
-
-The write file is read/write. Writing a value outputs it on the I/O
-port. Reading returns the last written value. As it is not possible
-to read this value from the chip, you need to write at least once to
-this file before you can read back from it.
diff --git a/Documentation/i2c/chips/pcf8575 b/Documentation/i2c/chips/pcf8575
deleted file mode 100644
index 40b268eb276f..000000000000
--- a/Documentation/i2c/chips/pcf8575
+++ /dev/null
@@ -1,69 +0,0 @@
-About the PCF8575 chip and the pcf8575 kernel driver
-====================================================
-
-The PCF8575 chip is produced by the following manufacturers:
-
- * Philips NXP
- http://www.nxp.com/#/pip/cb=[type=product,path=50807/41735/41850,final=PCF8575_3]|pip=[pip=PCF8575_3][0]
-
- * Texas Instruments
- http://focus.ti.com/docs/prod/folders/print/pcf8575.html
-
-
-Some vendors sell small PCB's with the PCF8575 mounted on it. You can connect
-such a board to a Linux host via e.g. an USB to I2C interface. Examples of
-PCB boards with a PCF8575:
-
- * SFE Breakout Board for PCF8575 I2C Expander by RobotShop
- http://www.robotshop.ca/home/products/robot-parts/electronics/adapters-converters/sfe-pcf8575-i2c-expander-board.html
-
- * Breakout Board for PCF8575 I2C Expander by Spark Fun Electronics
- http://www.sparkfun.com/commerce/product_info.php?products_id=8130
-
-
-Description
------------
-The PCF8575 chip is a 16-bit I/O expander for the I2C bus. Up to eight of
-these chips can be connected to the same I2C bus. You can find this
-chip on some custom designed hardware, but you won't find it on PC
-motherboards.
-
-The PCF8575 chip consists of a 16-bit quasi-bidirectional port and an I2C-bus
-interface. Each of the sixteen I/O's can be independently used as an input or
-an output. To set up an I/O pin as an input, you have to write a 1 to the
-corresponding output.
-
-For more information please see the datasheet.
-
-
-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 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
---------------
-
-For each address on which a PCF8575 chip was found or forced the following
-files will be created under /sys:
-* /sys/bus/i2c/devices/<bus>-<address>/read
-* /sys/bus/i2c/devices/<bus>-<address>/write
-where bus is the I2C bus number (0, 1, ...) and address is the four-digit
-hexadecimal representation of the 7-bit I2C address of the PCF8575
-(0020 .. 0027).
-
-The read file is read-only. Reading it will trigger an I2C read and will hence
-report the current input state for the pins configured as inputs, and the
-current output value for the pins configured as outputs.
-
-The write file is read-write. Writing a value to it will configure all pins
-as output for which the corresponding bit is zero. Reading the write file will
-return the value last written, or -EAGAIN if no value has yet been written to
-the write file.
-
-On module initialization the configuration of the chip is not changed -- the
-chip is left in the state it was already configured in through either power-up
-or through previous I2C write actions.
OpenPOWER on IntegriCloud