Re: [PATCH v2 04/13] i3c: master: Support ACPI enumeration of child devices

Akhil R
2026-04-10T05:32:20Z

On Thu, 9 Apr 2026 22:17:22 -0400, Frank Li wrote:
> On Thu, Apr 09, 2026 at 04:27:34PM +0530, Akhil R wrote:
>> Although the existing subsystem allows host controllers to register
>> through the ACPI table, it was not possible to describe I3C or I2C
>> devices when using ACPI. This is because the driver relied on reg
>> property to retrieve the PID, static address etc whereas ACPI uses
>> _ADR or serial resources to describe such devices.
>>
>> Read _ADR and LVR from the ACPI resources and extract the data as per the
>> ACPI specification for an I3C bus. Also read mipi-i3c-static-address as
>> per the MIPI DISCO specifications [1] to get the static address to be
>> used. Hence enable describing the I3C or I2C devices in the ACPI
>> table, which is required if the device is using a static address or if it
>> needs some specific properties to be attached to it.
>
> Please wrap your commit message at 75 char.

Ack. Will do.

>
>>
>> [1] https://www.mipi.org/mipi-disco-for-i3c-download
>>
>> Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
>> ---
>> drivers/i3c/master.c | 140 ++++++++++++++++++++++++++++++++++++++++---
>> 1 file changed, 132 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
>> index 5e0e926f61f3..08d0fcabd6f1 100644
>> --- a/drivers/i3c/master.c
>> +++ b/drivers/i3c/master.c
>> @@ -5,6 +5,7 @@
>> * Author: Boris Brezillon <boris.brezillon@bootlin.com>
>> */
>>
>> +#include <linux/acpi.h>
>> #include <linux/atomic.h>
>> #include <linux/bug.h>
>> #include <linux/device.h>
>> @@ -2403,6 +2404,53 @@ EXPORT_SYMBOL_GPL(i3c_master_add_i3c_dev_locked);
>>
>> #define OF_I3C_REG1_IS_I2C_DEV BIT(31)
>>
>> +#ifdef CONFIG_ACPI
> ...
>
>> +#ifdef CONFIG_ACPI
>> +static int i3c_master_add_acpi_dev(struct i3c_master_controller *master,
>> + struct fwnode_handle *fwnode)
>
>
> Can you move this and below function to previous #ifdef CONFIG_ACPI block.

Ack. I will update, but there are some cross-dependencies. We may have to
add a few function prototypes with the headers if we have to move these
under the same block. Hope that is fine.

Best Regards,
Akhil