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| author | Wolfram Sang <w.sang@pengutronix.de> | 2009-09-18 22:45:48 +0200 |
|---|---|---|
| committer | Jean Delvare <khali@linux-fr.org> | 2009-09-18 22:45:48 +0200 |
| commit | 732d481127abaa0add41ee918191ea08e9ede17e (patch) | |
| tree | 8d2c939552826eb604882a8dd027bc67832d96e6 /Documentation/i2c | |
| parent | 8f67eeb0b44cde19216955975ffef8513a87c0c0 (diff) | |
| download | lwn-732d481127abaa0add41ee918191ea08e9ede17e.tar.gz lwn-732d481127abaa0add41ee918191ea08e9ede17e.zip | |
i2c/chips: Remove deprecated pca9539 driver
The pca9539 driver in drivers/i2c/chips which just exports its registers to
sysfs is superseded by drivers/gpio/pca953x.c which properly uses the gpiolib.
As this driver has been deprecated for more than a year, finally remove it.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Ben Gardner <gardner.ben@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to 'Documentation/i2c')
| -rw-r--r-- | Documentation/i2c/chips/pca9539 | 58 |
1 files changed, 0 insertions, 58 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 - |