Re: [PATCH v2 06/13] i3c: master: Add support for devices without PID

Frank Li
2026-04-10T02:37:19Z

On Thu, Apr 09, 2026 at 04:27:36PM +0530, Akhil R wrote:
> Devices using SETAASA for address assignment are not required to have
> a 48-bit PID according to the I3C specification. Allow such devices to
> register and use the static address where PID was required.
>
> Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>
> drivers/i3c/master.c | 51 ++++++++++++++++++++++++++++++++++----------
> 1 file changed, 40 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index a0f7a0d35f3f..324a0440724e 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -1835,8 +1835,17 @@ i3c_master_register_new_i3c_devs(struct i3c_master_controller *master)
> desc->dev->dev.type = &i3c_device_type;
> desc->dev->dev.bus = &i3c_bus_type;
> desc->dev->dev.release = i3c_device_release;
> - dev_set_name(&desc->dev->dev, "%d-%llx", master->bus.id,
> - desc->info.pid);
> +
> + /*
> + * For devices without PID (e.g., SETAASA devices), use
> + * static address for naming instead.
> + */
> + if (desc->info.pid)
> + dev_set_name(&desc->dev->dev, "%d-%llx", master->bus.id,
> + desc->info.pid);
> + else
> + dev_set_name(&desc->dev->dev, "%d-%02x", master->bus.id,
> + desc->info.static_addr);
>
> if (desc->boardinfo)
> device_set_node(&desc->dev->dev, desc->boardinfo->fwnode);
> @@ -2285,8 +2294,18 @@ static void i3c_master_attach_boardinfo(struct i3c_dev_desc *i3cdev)
> struct i3c_dev_boardinfo *i3cboardinfo;
>
> list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) {
> - if (i3cdev->info.pid != i3cboardinfo->pid)
> - continue;
> + /*
> + * For devices without PID (e.g., SETAASA devices), match by
> + * static address. For devices with PID, match by PID.
> + */
> + if (i3cboardinfo->pid) {
> + if (i3cdev->info.pid != i3cboardinfo->pid)
> + continue;
> + } else {
> + if (!i3cboardinfo->static_addr ||
> + i3cdev->info.static_addr != i3cboardinfo->static_addr)
> + continue;
> + }
>
> i3cdev->boardinfo = i3cboardinfo;
> i3cdev->info.static_addr = i3cboardinfo->static_addr;
> @@ -2300,8 +2319,12 @@ i3c_master_search_i3c_dev_duplicate(struct i3c_dev_desc *refdev)
> struct i3c_master_controller *master = i3c_dev_get_master(refdev);
> struct i3c_dev_desc *i3cdev;
>
> + if (!refdev->info.pid)
> + return NULL;
> +
> i3c_bus_for_each_i3cdev(&master->bus, i3cdev) {
> - if (i3cdev != refdev && i3cdev->info.pid == refdev->info.pid)
> + if (i3cdev != refdev && i3cdev->info.pid &&
> + i3cdev->info.pid == refdev->info.pid)
> return i3cdev;
> }
>
> @@ -2601,9 +2624,15 @@ i3c_master_add_i3c_boardinfo(struct i3c_master_controller *master,
>
> boardinfo->pid = ((u64)reg[1] << 32) | reg[2];
>
> - if ((boardinfo->pid & GENMASK_ULL(63, 48)) ||
> - I3C_PID_RND_LOWER_32BITS(boardinfo->pid))
> - return -EINVAL;
> + /* For SETAASA devices, validate the static address instead of PID */
> + if (boardinfo->static_addr_method & I3C_ADDR_METHOD_SETAASA) {
> + if (!boardinfo->static_addr)
> + return -EINVAL;
> + } else {
> + if ((boardinfo->pid & GENMASK_ULL(63, 48)) ||
> + I3C_PID_RND_LOWER_32BITS(boardinfo->pid))
> + return -EINVAL;
> + }
>
> boardinfo->init_dyn_addr = init_dyn_addr;
> boardinfo->fwnode = fwnode_handle_get(fwnode);
> @@ -2626,10 +2655,10 @@ static int i3c_master_add_of_dev(struct i3c_master_controller *master,
> return ret;
>
> /*
> - * The manufacturer ID can't be 0. If reg[1] == 0 that means we're
> - * dealing with an I2C device.
> + * I3C device should have either the manufacturer ID specified or the
> + * address discovery method specified. Else treat it as an I2C device.
> */
> - if (!reg[1])
> + if (!reg[1] && !fwnode_property_present(fwnode, "mipi-i3c-static-method"))
> ret = i3c_master_add_i2c_boardinfo(master, fwnode, reg);
> else
> ret = i3c_master_add_i3c_boardinfo(master, fwnode, reg);
> --
> 2.50.1