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>

1 files changed, 32 insertions, 5 deletions

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 */