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authoreric miao <eric.miao@marvell.com>2008-02-04 22:28:26 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2008-02-05 09:44:13 -0800
commit9e60fdcf0c2905d7a8fc4cb2b3711ea5c5acaae1 (patch)
treec90417ab0e2079d0355ffb553985d9a0f2348bab /include/linux/i2c
parente58b9e2762a6ef99e20dba47aba21b911658541d (diff)
downloadop-kernel-dev-9e60fdcf0c2905d7a8fc4cb2b3711ea5c5acaae1.zip
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gpiolib: pca9539 i2c gpio expander support
This adds a new-style I2C driver with basic support for the sixteen bit PCA9539 GPIO expanders. These chips have multiple registers, push-pull output drivers, and (not supported in this patch) pin change interrupts. Board-specific code must provide "pca9539_platform_data" with each chip's "i2c_board_info". That provides the GPIO numbers to be used by that chip, and callbacks for board-specific setup/teardown logic. Derived from drivers/i2c/chips/pca9539.c (which has no current known users). This is faster and simpler; it uses 16-bit register access, and cache the OUTPUT and DIRECTION registers for fast access Signed-off-by: eric miao <eric.miao@marvell.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Jean Delvare <khali@linux-fr.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: Philipp Zabel <philipp.zabel@gmail.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/i2c')
-rw-r--r--include/linux/i2c/pca9539.h18
1 files changed, 18 insertions, 0 deletions
diff --git a/include/linux/i2c/pca9539.h b/include/linux/i2c/pca9539.h
new file mode 100644
index 0000000..611d84a
--- /dev/null
+++ b/include/linux/i2c/pca9539.h
@@ -0,0 +1,18 @@
+/* platform data for the PCA9539 16-bit I/O expander driver */
+
+struct pca9539_platform_data {
+ /* number of the first GPIO */
+ unsigned gpio_base;
+
+ /* initial polarity inversion setting */
+ uint16_t invert;
+
+ void *context; /* param to setup/teardown */
+
+ int (*setup)(struct i2c_client *client,
+ unsigned gpio, unsigned ngpio,
+ void *context);
+ int (*teardown)(struct i2c_client *client,
+ unsigned gpio, unsigned ngpio,
+ void *context);
+};
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