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.

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.
Richard Retanubun · Heiko Schocher
1 parent 2a72e9ed18
Showing 3 changed files with 27 additions and 3 deletions Side-by-side Diff
README
drivers/i2c/fsl_i2c.c
include/i2c.h
@@ -1509,6 +1509,17 @@
 		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
@@ -221,9 +221,10 @@
 	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);
@@ -248,6 +249,15 @@
 	writeb(slaveadd << 1, &dev->adr);	/* write slave address */
 	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
 }
  
@@ -111,6 +111,9 @@
 #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)
...	...	@@ -1509,6 +1509,17 @@
1509	1509	custom i2c_init_board() routine in boards/xxx/board.c
1510	1510	is run early in the boot sequence.
1511	1511
	1512	+ CONFIG_SYS_I2C_BOARD_LATE_INIT
	1513	+
	1514	+ An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
	1515	+ defined a custom i2c_board_late_init() routine in
	1516	+ boards/xxx/board.c is run AFTER the operations in i2c_init()
	1517	+ is completed. This callpoint can be used to unreset i2c bus
	1518	+ using CPU i2c controller register accesses for CPUs whose i2c
	1519	+ controller provide such a method. It is called at the end of
	1520	+ i2c_init() to allow i2c_init operations to setup the i2c bus
	1521	+ controller on the CPU (e.g. setting bus speed & slave address).
	1522	+
1512	1523	CONFIG_I2CFAST (PPC405GP\|PPC405EP only)
1513	1524
1514	1525	This option enables configuration of bi_iic_fast[] flags
...	...	@@ -221,9 +221,10 @@
221	221	unsigned int temp;
222	222
223	223	#ifdef CONFIG_SYS_I2C_INIT_BOARD
224		- /* call board specific i2c bus reset routine before accessing the */
225		- /* environment, which might be in a chip on that bus. For details */
226		- /* about this problem see doc/I2C_Edge_Conditions. */
	224	+ /* Call board specific i2c bus reset routine before accessing the
	225	+ * environment, which might be in a chip on that bus. For details
	226	+ * about this problem see doc/I2C_Edge_Conditions.
	227	+ */
227	228	i2c_init_board();
228	229	#endif
229	230	dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET);
...	...	@@ -248,6 +249,15 @@
248	249	writeb(slaveadd << 1, &dev->adr); /* write slave address */
249	250	writeb(0x0, &dev->sr); /* clear status register */
250	251	writeb(I2C_CR_MEN, &dev->cr); /* start I2C controller */
	252	+#endif
	253	+
	254	+#ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
	255	+ /* Call board specific i2c bus reset routine AFTER the bus has been
	256	+ * initialized. Use either this callpoint or i2c_init_board;
	257	+ * which is called before i2c_init operations.
	258	+ * For details about this problem see doc/I2C_Edge_Conditions.
	259	+ */
	260	+ i2c_board_late_init();
251	261	#endif
252	262	}
253	263
...	...	@@ -111,6 +111,9 @@
111	111	#ifdef CONFIG_SYS_I2C_INIT_BOARD
112	112	void i2c_init_board(void);
113	113	#endif
	114	+#ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
	115	+void i2c_board_late_init(void);
	116	+#endif
114	117
115	118	#if defined(CONFIG_I2C_MUX)
116	119