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>
diff --git a/include/linux/i2c-algo-pca.h b/include/linux/i2c-algo-pca.h
index fce47c0..adcb3dc 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 */