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author | Wolfram Sang <w.sang@pengutronix.de> | 2008-04-22 22:16:46 +0200 |
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committer | Jean Delvare <khali@hyperion.delvare> | 2008-04-22 22:16:46 +0200 |
commit | c01b0831057381c7f6e0bfb3634bac8c5f7fb256 (patch) | |
tree | 43fb4c2d626df0c32f3196c81062592ab60ccd12 /include/linux/i2c-algo-pca.h | |
parent | 3d4382913f9a86f0d9ff47740feb427415fe7234 (diff) | |
download | linux-stable-c01b0831057381c7f6e0bfb3634bac8c5f7fb256.tar.gz linux-stable-c01b0831057381c7f6e0bfb3634bac8c5f7fb256.tar.bz2 linux-stable-c01b0831057381c7f6e0bfb3634bac8c5f7fb256.zip |
i2c-algo-pca: Extend for future drivers
The separation between algorithm and adapter was unsharp at places. This was
partly hidden by the fact, that the ISA-driver allowed just one instance and
had all private data in static variables. This patch makes neccessary
preparations to add a platform driver on top of the algorithm, while still
supporting ISA. Note: Due to lack of hardware, the ISA-driver could not be
tested except that it builds.
Concerning the core struct i2c_algo_pca_data:
- A private data field was added, all hardware dependant data may go here.
Similar to other algorithms, now a pointer to this data is passed to the
adapter's functions. In order to make as less changes as possible to the
ISA-driver, it leaves the private data empty and still only uses its static
variables.
- A "reset_chip" function pointer was added; such a functionality must come
from the adapter, not the algorithm.
- use a variable "i2c_clock" instead of a function pointer "get_clock",
allowing for write access to a default in case a wrong value was supplied.
In the algorithm-file:
- move "i2c-pca-algo.h" into "linux/i2c-algo-pca.h"
- now using per_instance timeout values (i2c_adap->timeout)
- error messages specify the device, not only the driver name
- restructure initialization to easily support "i2c_add_numbered_adapter"
- drop "retries" and "own" (i2c address) as they were unused
(The state-machine for I2C-communication was not touched.)
In the ISA-driver:
- adapt to new algorithm
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to 'include/linux/i2c-algo-pca.h')
-rw-r--r-- | include/linux/i2c-algo-pca.h | 37 |
1 files changed, 32 insertions, 5 deletions
diff --git a/include/linux/i2c-algo-pca.h b/include/linux/i2c-algo-pca.h index fce47c051bb1..adcb3dc7ac26 100644 --- a/include/linux/i2c-algo-pca.h +++ b/include/linux/i2c-algo-pca.h @@ -1,14 +1,41 @@ #ifndef _LINUX_I2C_ALGO_PCA_H #define _LINUX_I2C_ALGO_PCA_H +/* Clock speeds for the bus */ +#define I2C_PCA_CON_330kHz 0x00 +#define I2C_PCA_CON_288kHz 0x01 +#define I2C_PCA_CON_217kHz 0x02 +#define I2C_PCA_CON_146kHz 0x03 +#define I2C_PCA_CON_88kHz 0x04 +#define I2C_PCA_CON_59kHz 0x05 +#define I2C_PCA_CON_44kHz 0x06 +#define I2C_PCA_CON_36kHz 0x07 + +/* PCA9564 registers */ +#define I2C_PCA_STA 0x00 /* STATUS Read Only */ +#define I2C_PCA_TO 0x00 /* TIMEOUT Write Only */ +#define I2C_PCA_DAT 0x01 /* DATA Read/Write */ +#define I2C_PCA_ADR 0x02 /* OWN ADR Read/Write */ +#define I2C_PCA_CON 0x03 /* CONTROL Read/Write */ + +#define I2C_PCA_CON_AA 0x80 /* Assert Acknowledge */ +#define I2C_PCA_CON_ENSIO 0x40 /* Enable */ +#define I2C_PCA_CON_STA 0x20 /* Start */ +#define I2C_PCA_CON_STO 0x10 /* Stop */ +#define I2C_PCA_CON_SI 0x08 /* Serial Interrupt */ +#define I2C_PCA_CON_CR 0x07 /* Clock Rate (MASK) */ + struct i2c_algo_pca_data { - int (*get_own) (struct i2c_algo_pca_data *adap); /* Obtain own address */ - int (*get_clock) (struct i2c_algo_pca_data *adap); - void (*write_byte) (struct i2c_algo_pca_data *adap, int reg, int val); - int (*read_byte) (struct i2c_algo_pca_data *adap, int reg); - int (*wait_for_interrupt) (struct i2c_algo_pca_data *adap); + void *data; /* private low level data */ + void (*write_byte) (void *data, int reg, int val); + int (*read_byte) (void *data, int reg); + int (*wait_for_completion) (void *data); + void (*reset_chip) (void *data); + /* i2c_clock values are defined in linux/i2c-algo-pca.h */ + unsigned int i2c_clock; }; int i2c_pca_add_bus(struct i2c_adapter *); +int i2c_pca_add_numbered_bus(struct i2c_adapter *); #endif /* _LINUX_I2C_ALGO_PCA_H */ |