From bb99ad6d8257bf828f150d40f507b30d80a4a7ae Mon Sep 17 00:00:00 2001 From: Ben Warren Date: Thu, 7 Sep 2006 16:50:54 -0400 Subject: 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 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 --- include/i2c.h | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) (limited to 'include/i2c.h') diff --git a/include/i2c.h b/include/i2c.h index 6d39080d8..97e006163 100644 --- a/include/i2c.h +++ b/include/i2c.h @@ -82,4 +82,49 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len); 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_ */ -- cgit v1.2.3