Commit 5eb6d356 authored by Defa Li's avatar Defa Li Committed by Alexandre Belloni
Browse files

i3c: master: Improve initialization of numbered I2C adapters 



Add logic to initialize I2C adapters with a specific ID if available,
improving device identification and configuration.

For mixed buses, in addition to the i3c alias, an i2c alias can be added to
assign a fixed bus number to the i2c adapter.

This allows an alias node such as:
    aliases {
        i2c2 = &mixed_bus_a,
        i3c2 = &mixed_bus_a,
        i3c4 = &mixed_bus_b,
    };

    /* assigned "i3c-2" and "i2c-2" */
    mixed_bus_a: i3c-master {
    };

If there is no i2c alias for a mixed bus, the i2c adapter numbers will
remain as is and will be assigned starting after the highest fixed bus
number.

    /* assigned "i3c-4" and likely assigned "i2c-3" */
    mixed_bus_b: i3c-master {
    };

Signed-off-by: default avatarDefa Li <defa.li@mediatek.com>
Reviewed-by: default avatarFrank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20241212091818.8591-1-defa.li@mediatek.com


Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent b266e0d4

drivers/i3c/master.c

+10 −2
Original line number Diff line number Diff line
@@ -2486,7 +2486,7 @@ static int i3c_master_i2c_adapter_init(struct i3c_master_controller *master) 
	struct i2c_adapter *adap = i3c_master_to_i2c_adapter(master);

	struct i2c_dev_desc *i2cdev;

	struct i2c_dev_boardinfo *i2cboardinfo;

	int ret;

	int ret, id = -ENODEV;



	adap->dev.parent = master->dev.parent;

	adap->owner = master->dev.parent->driver->owner;
@@ -2497,7 +2497,15 @@ static int i3c_master_i2c_adapter_init(struct i3c_master_controller *master) 
	adap->timeout = 1000;

	adap->retries = 3;



	if (master->dev.of_node)

		id = of_alias_get_id(master->dev.of_node, "i2c");



	if (id >= 0) {

		adap->nr = id;

		ret = i2c_add_numbered_adapter(adap);

	} else {

		ret = i2c_add_adapter(adap);

	}

	if (ret)

		return ret;