drivers/i3c/master.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)
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 {
};
v2:
- Modify commit message and code format issues
Signed-off-by: Defa Li <defa.li@mediatek.com>
---
drivers/i3c/master.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 42310c9a00c2..92223e0b6e59 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -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;
- ret = i2c_add_adapter(adap);
+ 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;
--
2.46.0
On Thu, 12 Dec 2024 17:17:53 +0800, Defa Li wrote:
> 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,
> };
>
> [...]
Applied, thanks!
[1/1] i3c: master: Improve initialization of numbered I2C adapters
https://git.kernel.org/abelloni/c/5eb6d3561f6c
Best regards,
--
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
On Thu, Dec 12, 2024 at 05:17:53PM +0800, Defa Li wrote:
> 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 {
> };
>
> v2:
> - Modify commit message and code format issues
v2: ...
should be after "---"
>
> Signed-off-by: Defa Li <defa.li@mediatek.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
> ---
> drivers/i3c/master.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index 42310c9a00c2..92223e0b6e59 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -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;
>
> - ret = i2c_add_adapter(adap);
> + 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;
>
> --
> 2.46.0
>
>
> --
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> linux-i3c@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-i3c
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