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authorJean Delvare <khali@linux-fr.org>2008-07-16 19:30:07 +0200
committerJean Delvare <khali@mahadeva.delvare>2008-07-16 19:30:07 +0200
commit3d63430a26b91fe3daee0dd933f899c225e66daa (patch)
tree88b10cf9d53c2c84f13eb60db0e6304ad8eff6da /Documentation/i2c
parent97addff6def3f8e228a634fa017589f45c69de5c (diff)
downloadblackbird-op-linux-3d63430a26b91fe3daee0dd933f899c225e66daa.tar.gz
blackbird-op-linux-3d63430a26b91fe3daee0dd933f899c225e66daa.zip
i2c: Convert the pca9539 driver to a new-style i2c driver
The new-style pca9539 driver implements the optional detect() callback to cover the use cases of the legacy driver. Warning: users will now have to use the force module parameter to get the driver to attach to their device. That's not a bad thing as these devices can't be detected anyway. Note that this doesn't change the fact that this driver is deprecated in favor of gpio/pca953x. Signed-off-by: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to 'Documentation/i2c')
-rw-r--r--Documentation/i2c/chips/pca953910
1 files changed, 9 insertions, 1 deletions
diff --git a/Documentation/i2c/chips/pca9539 b/Documentation/i2c/chips/pca9539
index 1d81c530c4a5..6aff890088b1 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
-------------
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