[RFC 0/1] i2c: omap: Add support for switching to slave mode

From: Ravikumar Kattekola
Date: Wed May 25 2016 - 10:11:45 EST


I2C controller on most of the omap devices has both master and slave
capability but the i2c framework has been missing support for registering
a bus in slave mode for long.
Recently the i2c slave support has been added to i2c framework, the following
patch adds the required support for omap_i2c driver to register a controller
as a slave device and be deriven by an external/internal master.

The slave interface requires us to add following mandatory events

1. I2C_SLAVE_WRITE_REQUESTED
2. I2C_SLAVE_READ_REQUESTED
3. I2C_SLAVE_WRITE_RECEIVED
4. I2C_SLAVE_READ_PROCESSED

and

5. I2C_SLAVE_STOP

The omap i2c controller (at least on dra7x devices)
doesn't have start/stop (STT/STP) support for slave mode
so event #5 is not implemented in the driver.

Refer to Documentation/i2c/slave-interface for more info on
i2c-slave-interface and Documentation/i2c/slave-eeprom-backend for
sample backend driver.

Tested on:
DRA75x EVM Rev G3 and DRA72x EVM Rev B1 connected over i2c3 using DCAN2 lines [JP3]

Ravikumar Kattekola (1):
drivers: i2c: omap: Add slave support

drivers/i2c/busses/i2c-omap.c | 144 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 144 insertions(+)

--
2.8.2.396.g5fe494c