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-rw-r--r--README11
-rw-r--r--drivers/i2c/fsl_i2c.c16
-rw-r--r--include/i2c.h3
3 files changed, 27 insertions, 3 deletions
diff --git a/README b/README
index 4a50557f6d..cdd81d4efe 100644
--- a/README
+++ b/README
@@ -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
diff --git a/drivers/i2c/fsl_i2c.c b/drivers/i2c/fsl_i2c.c
index 2241990f94..cb13deeea9 100644
--- a/drivers/i2c/fsl_i2c.c
+++ b/drivers/i2c/fsl_i2c.c
@@ -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
diff --git a/include/i2c.h b/include/i2c.h
index d828964256..cd23c8ac12 100644
--- a/include/i2c.h
+++ b/include/i2c.h
@@ -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)
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