Add support for multiple I2C buses
Hello,
Attached is a patch providing support for multiple I2C buses at the
command level. The second part of the patch includes an implementation
for the MPC834x CPU and MPC8349EMDS board.
/*** Note: This patch replaces ticket DNX#2006083042000018 ***/
Signed-off-by: Ben Warren <bwarren@qstreams.com>
Overview:
1. Include new 'i2c' command (based on USB implementation) using
CONFIG_I2C_CMD_TREE.
2. Allow multiple buses by defining CONFIG_I2C_MULTI_BUS. Note that
the commands to change bus number and speed are only available under the
new 'i2c' command mentioned in the first bullet.
3. The option CFG_I2C_NOPROBES has been expanded to work in multi-bus
systems. When CONFIG_I2C_MULTI_BUS is used, this option takes the form
of an array of bus-device pairs. Otherwise, it is an array of uchar.
CHANGELOG:
Added new 'i2c' master command for all I2C interaction. This is
conditionally compiled with CONFIG_I2C_CMD_TREE. New commands added for
setting I2C bus speed as well as changing the active bus if the board
has more than one (conditionally compiled with
CONFIG_I2C_MULTI_BUS). Updated NOPROBE logic to handle multiple buses.
Updated README.
regards,
Ben
diff --git a/include/i2c.h b/include/i2c.h
index 6d39080..97e0061 100644
--- a/include/i2c.h
+++ b/include/i2c.h
@@ -82,4 +82,49 @@
uchar i2c_reg_read (uchar chip, uchar reg);
void i2c_reg_write(uchar chip, uchar reg, uchar val);
+/*
+ * Functions for setting the current I2C bus and its speed
+ */
+
+/*
+ * i2c_set_bus_num:
+ *
+ * Change the active I2C bus. Subsequent read/write calls will
+ * go to this one.
+ *
+ * bus - bus index, zero based
+ *
+ * Returns: 0 on success, not 0 on failure
+ *
+ */
+int i2c_set_bus_num(uchar bus);
+
+/*
+ * i2c_get_bus_num:
+ *
+ * Returns index of currently active I2C bus. Zero-based.
+ */
+
+uchar i2c_get_bus_num(void);
+
+/*
+ * i2c_set_bus_speed:
+ *
+ * Change the speed of the active I2C bus
+ *
+ * speed - bus speed in Hz
+ *
+ * Returns: 0 on success, not 0 on failure
+ *
+ */
+int i2c_set_bus_speed(int);
+
+/*
+ * i2c_get_bus_speed:
+ *
+ * Returns speed of currently active I2C bus in Hz
+ */
+
+int i2c_get_bus_speed(void);
+
#endif /* _I2C_H_ */