fsl_i2c: Added a callpoint for i2c_board_late_init

This patch adds a callpoint in i2c_init that allows board specific
i2c board initialization (typically for i2c bus reset) that is called
after i2c_init operations, allowing the i2c_board_late_init function
to use the pre-configured i2c bus speed and slave address.
This commit is contained in:
Richard Retanubun 2010-04-12 15:08:17 -04:00 committed by Heiko Schocher
parent 2a72e9ed18
commit 26a33504a5
3 changed files with 27 additions and 3 deletions

11
README
View File

@ -1509,6 +1509,17 @@ The following options need to be configured:
custom i2c_init_board() routine in boards/xxx/board.c
is run early in the boot sequence.
CONFIG_SYS_I2C_BOARD_LATE_INIT
An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
defined a custom i2c_board_late_init() routine in
boards/xxx/board.c is run AFTER the operations in i2c_init()
is completed. This callpoint can be used to unreset i2c bus
using CPU i2c controller register accesses for CPUs whose i2c
controller provide such a method. It is called at the end of
i2c_init() to allow i2c_init operations to setup the i2c bus
controller on the CPU (e.g. setting bus speed & slave address).
CONFIG_I2CFAST (PPC405GP|PPC405EP only)
This option enables configuration of bi_iic_fast[] flags

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@ -221,9 +221,10 @@ i2c_init(int speed, int slaveadd)
unsigned int temp;
#ifdef CONFIG_SYS_I2C_INIT_BOARD
/* call board specific i2c bus reset routine before accessing the */
/* environment, which might be in a chip on that bus. For details */
/* about this problem see doc/I2C_Edge_Conditions. */
/* Call board specific i2c bus reset routine before accessing the
* environment, which might be in a chip on that bus. For details
* about this problem see doc/I2C_Edge_Conditions.
*/
i2c_init_board();
#endif
dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET);
@ -249,6 +250,15 @@ i2c_init(int speed, int slaveadd)
writeb(0x0, &dev->sr); /* clear status register */
writeb(I2C_CR_MEN, &dev->cr); /* start I2C controller */
#endif
#ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
/* Call board specific i2c bus reset routine AFTER the bus has been
* initialized. Use either this callpoint or i2c_init_board;
* which is called before i2c_init operations.
* For details about this problem see doc/I2C_Edge_Conditions.
*/
i2c_board_late_init();
#endif
}
static int

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@ -111,6 +111,9 @@ void i2c_init(int speed, int slaveaddr);
#ifdef CONFIG_SYS_I2C_INIT_BOARD
void i2c_init_board(void);
#endif
#ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
void i2c_board_late_init(void);
#endif
#if defined(CONFIG_I2C_MUX)