[v2] Introduce initial support for the AMD I3C (non-HCI) to DW driver

[PATCH v2 3/6] i3c: master: Add ACPI support to i3c subsystem

Posted by Shyam Sundar S K 1 month ago

As of now, the I3C subsystem only has ARM-specific initialization, and
there is no corresponding ACPI plumbing present. To address this, ACPI
support needs to be added to both the I3C core and DW driver.

Add support to get the ACPI handle from the _HID probed and parse the apci
object to retrieve the slave information from BIOS.

Based on the acpi object information propogated via BIOS, build the i3c
board information so that the same information can be used across the
driver to handle the slave requests.

Co-developed-by: Sanket Goswami <Sanket.Goswami@amd.com>
Signed-off-by: Sanket Goswami <Sanket.Goswami@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
---
 drivers/i3c/internals.h            |  2 +
 drivers/i3c/master.c               | 84 ++++++++++++++++++++++++++++++
 drivers/i3c/master/dw-i3c-master.c |  7 +++
 include/linux/i3c/master.h         |  1 +
 4 files changed, 94 insertions(+)

diff --git a/drivers/i3c/internals.h b/drivers/i3c/internals.h
index 433f6088b7ce..d2d6c69b19dd 100644
--- a/drivers/i3c/internals.h
+++ b/drivers/i3c/internals.h
@@ -10,6 +10,8 @@
 
 #include <linux/i3c/master.h>
 
+#define AMD_I3C_GET_SLAVE_ADDR		0x30
+
 void i3c_bus_normaluse_lock(struct i3c_bus *bus);
 void i3c_bus_normaluse_unlock(struct i3c_bus *bus);
 
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 6f3eb710a75d..7d23c32e1c0f 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -2251,6 +2251,84 @@ static int of_i3c_master_add_dev(struct i3c_master_controller *master,
 	return ret;
 }
 
+#if IS_ENABLED(CONFIG_ACPI)
+static int i3c_acpi_configure_master(struct i3c_master_controller *master)
+{
+	struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
+	enum i3c_addr_slot_status addrstatus;
+	struct i3c_dev_boardinfo *boardinfo;
+	struct device *dev = &master->dev;
+	struct fwnode_handle *fwnode;
+	struct acpi_device *adev;
+	u32 slv_addr, num_dev;
+	acpi_status status;
+	u64 val;
+
+	status = acpi_evaluate_object_typed(master->ahandle, "_DSD", NULL, &buf, ACPI_TYPE_PACKAGE);
+	if (ACPI_FAILURE(status)) {
+		dev_err(&master->dev, "Error reading _DSD:%s\n", acpi_format_exception(status));
+		return -ENODEV;
+	}
+
+	num_dev = device_get_child_node_count(dev);
+	if (!num_dev) {
+		dev_err(&master->dev, "Error: no child node present\n");
+		return -EINVAL;
+	}
+
+	device_for_each_child_node(dev, fwnode) {
+		adev = to_acpi_device_node(fwnode);
+		if (!adev)
+			return -ENODEV;
+
+		status = acpi_evaluate_integer(adev->handle, "_ADR", NULL, &val);
+		if (ACPI_FAILURE(status)) {
+			dev_err(&master->dev, "Error: eval _ADR failed\n");
+			return -EINVAL;
+		}
+		slv_addr = val >> AMD_I3C_GET_SLAVE_ADDR;
+
+		boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
+		if (!boardinfo)
+			return -ENOMEM;
+
+		if (slv_addr) {
+			if (slv_addr > I3C_MAX_ADDR)
+				return -EINVAL;
+
+			addrstatus = i3c_bus_get_addr_slot_status(&master->bus, slv_addr);
+			if (addrstatus != I3C_ADDR_SLOT_FREE)
+				return -EINVAL;
+		}
+
+		boardinfo->static_addr = slv_addr;
+		if (boardinfo->static_addr > I3C_MAX_ADDR)
+			return -EINVAL;
+
+		addrstatus = i3c_bus_get_addr_slot_status(&master->bus,	boardinfo->static_addr);
+		if (addrstatus != I3C_ADDR_SLOT_FREE)
+			return -EINVAL;
+
+		boardinfo->pid = (val & GENMASK(47, 0));
+		if ((boardinfo->pid & GENMASK_ULL(63, 48)) ||
+		    I3C_PID_RND_LOWER_32BITS(boardinfo->pid))
+			return -EINVAL;
+
+		/*
+		 * According to the specification, SETDASA is not supported for DIMM slaves
+		 * during device discovery. Therefore, AMD BIOS will populate same initial
+		 * dynamic address as the static address.
+		 */
+		boardinfo->init_dyn_addr = boardinfo->static_addr;
+		list_add_tail(&boardinfo->node, &master->boardinfo.i3c);
+	}
+
+	return 0;
+}
+#else
+static int i3c_acpi_configure_master(struct i3c_master_controller *master) { return 0; }
+#endif
+
 static int of_populate_i3c_bus(struct i3c_master_controller *master)
 {
 	struct device *dev = &master->dev;
@@ -2771,6 +2849,12 @@ int i3c_master_register(struct i3c_master_controller *master,
 	master->dev.coherent_dma_mask = parent->coherent_dma_mask;
 	master->dev.dma_parms = parent->dma_parms;
 
+	if (has_acpi_companion(master->dev.parent)) {
+		ret = i3c_acpi_configure_master(master);
+		if (ret < 0)
+			return ret;
+	}
+
 	ret = of_populate_i3c_bus(master);
 	if (ret)
 		goto err_put_dev;
diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index fd58a95ae1c3..f683e2a398ad 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -1602,6 +1602,13 @@ int dw_i3c_common_probe(struct dw_i3c_master *master,
 	master->maxdevs = ret >> 16;
 	master->free_pos = GENMASK(master->maxdevs - 1, 0);
 
+#if IS_ENABLED(CONFIG_ACPI)
+	ACPI_COMPANION_SET(&master->base.dev, ACPI_COMPANION(&pdev->dev));
+	master->base.ahandle = acpi_device_handle(ACPI_COMPANION(&pdev->dev));
+	if (!master->base.ahandle)
+		dev_err(&pdev->dev, "Failed to get acpi device handle\n");
+#endif
+
 	INIT_WORK(&master->hj_work, dw_i3c_hj_work);
 	ret = i3c_master_register(&master->base, &pdev->dev,
 				  &dw_mipi_i3c_ops, false);
diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
index 2a1ed05d5782..367faf7c4bf3 100644
--- a/include/linux/i3c/master.h
+++ b/include/linux/i3c/master.h
@@ -523,6 +523,7 @@ struct i3c_master_controller {
 	} boardinfo;
 	struct i3c_bus bus;
 	struct workqueue_struct *wq;
+	acpi_handle ahandle;
 };
 
 /**
-- 
2.34.1

Re: [PATCH v2 3/6] i3c: master: Add ACPI support to i3c subsystem

Posted by Jarkko Nikula 3 weeks ago

Hi

+ linux-acpi

On 10/23/24 8:51 AM, Shyam Sundar S K wrote:
> As of now, the I3C subsystem only has ARM-specific initialization, and
> there is no corresponding ACPI plumbing present. To address this, ACPI
> support needs to be added to both the I3C core and DW driver.
> 
> Add support to get the ACPI handle from the _HID probed and parse the apci
> object to retrieve the slave information from BIOS.
> 
> Based on the acpi object information propogated via BIOS, build the i3c
> board information so that the same information can be used across the
> driver to handle the slave requests.
> 
I think it would be good to have a DSDT example here?

> Co-developed-by: Sanket Goswami <Sanket.Goswami@amd.com>
> Signed-off-by: Sanket Goswami <Sanket.Goswami@amd.com>
> Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
> ---
>   drivers/i3c/internals.h            |  2 +
>   drivers/i3c/master.c               | 84 ++++++++++++++++++++++++++++++
>   drivers/i3c/master/dw-i3c-master.c |  7 +++
>   include/linux/i3c/master.h         |  1 +
>   4 files changed, 94 insertions(+)
> 
> diff --git a/drivers/i3c/internals.h b/drivers/i3c/internals.h
> index 433f6088b7ce..d2d6c69b19dd 100644
> --- a/drivers/i3c/internals.h
> +++ b/drivers/i3c/internals.h
> @@ -10,6 +10,8 @@
>   
>   #include <linux/i3c/master.h>
>   
> +#define AMD_I3C_GET_SLAVE_ADDR		0x30
> +
>   void i3c_bus_normaluse_lock(struct i3c_bus *bus);
>   void i3c_bus_normaluse_unlock(struct i3c_bus *bus);
>   
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index 6f3eb710a75d..7d23c32e1c0f 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -2251,6 +2251,84 @@ static int of_i3c_master_add_dev(struct i3c_master_controller *master,
>   	return ret;
>   }
>   
> +#if IS_ENABLED(CONFIG_ACPI)
> +static int i3c_acpi_configure_master(struct i3c_master_controller *master)
> +{
> +	struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
> +	enum i3c_addr_slot_status addrstatus;
> +	struct i3c_dev_boardinfo *boardinfo;
> +	struct device *dev = &master->dev;
> +	struct fwnode_handle *fwnode;
> +	struct acpi_device *adev;
> +	u32 slv_addr, num_dev;
> +	acpi_status status;
> +	u64 val;
> +
> +	status = acpi_evaluate_object_typed(master->ahandle, "_DSD", NULL, &buf, ACPI_TYPE_PACKAGE);
> +	if (ACPI_FAILURE(status)) {
> +		dev_err(&master->dev, "Error reading _DSD:%s\n", acpi_format_exception(status));
> +		return -ENODEV;
> +	}
> +
> +	num_dev = device_get_child_node_count(dev);
> +	if (!num_dev) {
> +		dev_err(&master->dev, "Error: no child node present\n");
> +		return -EINVAL;
> +	}
> +
> +	device_for_each_child_node(dev, fwnode) {
> +		adev = to_acpi_device_node(fwnode);
> +		if (!adev)
> +			return -ENODEV;
> +
> +		status = acpi_evaluate_integer(adev->handle, "_ADR", NULL, &val);
> +		if (ACPI_FAILURE(status)) {
> +			dev_err(&master->dev, "Error: eval _ADR failed\n");
> +			return -EINVAL;
> +		}
> +		slv_addr = val >> AMD_I3C_GET_SLAVE_ADDR;

This doesn't seem to match with ACPI 6.5 spec [1] chapter 6.1.1 _ADR 
(Address)? Address encoding for I3C says:

Bits [63:52] - Reserved
Bits [51:48] - Master Instance
Bits [47:0] - I3C Device Provisional ID, following encoding defined in 
the MIPI
Specification for I3C.
If an I3C device supports a static address instead of a Provisional ID, 
then bits
[47:7] are Reserved (zero), and bits [6:0] are the 7-bit static address.

1. https://uefi.org/sites/default/files/resources/ACPI_Spec_6_5_Aug29.pdf

> +
> +		boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
> +		if (!boardinfo)
> +			return -ENOMEM;
> +
> +		if (slv_addr) {
> +			if (slv_addr > I3C_MAX_ADDR)
> +				return -EINVAL;
> +
> +			addrstatus = i3c_bus_get_addr_slot_status(&master->bus, slv_addr);
> +			if (addrstatus != I3C_ADDR_SLOT_FREE)
> +				return -EINVAL;
> +		}
> +
> +		boardinfo->static_addr = slv_addr;
> +		if (boardinfo->static_addr > I3C_MAX_ADDR)
> +			return -EINVAL;
> +
> +		addrstatus = i3c_bus_get_addr_slot_status(&master->bus,	boardinfo->static_addr);
> +		if (addrstatus != I3C_ADDR_SLOT_FREE)
> +			return -EINVAL;
> +
> +		boardinfo->pid = (val & GENMASK(47, 0));
> +		if ((boardinfo->pid & GENMASK_ULL(63, 48)) ||
> +		    I3C_PID_RND_LOWER_32BITS(boardinfo->pid))
> +			return -EINVAL;
> +
> +		/*
> +		 * According to the specification, SETDASA is not supported for DIMM slaves
> +		 * during device discovery. Therefore, AMD BIOS will populate same initial
> +		 * dynamic address as the static address.
> +		 */
> +		boardinfo->init_dyn_addr = boardinfo->static_addr;
> +		list_add_tail(&boardinfo->node, &master->boardinfo.i3c);
> +	}
> +
> +	return 0;
> +}
> +#else
> +static int i3c_acpi_configure_master(struct i3c_master_controller *master) { return 0; }
> +#endif
> +
>   static int of_populate_i3c_bus(struct i3c_master_controller *master)
>   {
>   	struct device *dev = &master->dev;
> @@ -2771,6 +2849,12 @@ int i3c_master_register(struct i3c_master_controller *master,
>   	master->dev.coherent_dma_mask = parent->coherent_dma_mask;
>   	master->dev.dma_parms = parent->dma_parms;
>   
> +	if (has_acpi_companion(master->dev.parent)) {
> +		ret = i3c_acpi_configure_master(master);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
>   	ret = of_populate_i3c_bus(master);
>   	if (ret)
>   		goto err_put_dev;
> diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
> index fd58a95ae1c3..f683e2a398ad 100644
> --- a/drivers/i3c/master/dw-i3c-master.c
> +++ b/drivers/i3c/master/dw-i3c-master.c
> @@ -1602,6 +1602,13 @@ int dw_i3c_common_probe(struct dw_i3c_master *master,
>   	master->maxdevs = ret >> 16;
>   	master->free_pos = GENMASK(master->maxdevs - 1, 0);
>   
> +#if IS_ENABLED(CONFIG_ACPI)
> +	ACPI_COMPANION_SET(&master->base.dev, ACPI_COMPANION(&pdev->dev));
> +	master->base.ahandle = acpi_device_handle(ACPI_COMPANION(&pdev->dev));
> +	if (!master->base.ahandle)
> +		dev_err(&pdev->dev, "Failed to get acpi device handle\n");
> +#endif
> +
>   	INIT_WORK(&master->hj_work, dw_i3c_hj_work);
>   	ret = i3c_master_register(&master->base, &pdev->dev,
>   				  &dw_mipi_i3c_ops, false);
> diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
> index 2a1ed05d5782..367faf7c4bf3 100644
> --- a/include/linux/i3c/master.h
> +++ b/include/linux/i3c/master.h
> @@ -523,6 +523,7 @@ struct i3c_master_controller {
>   	} boardinfo;
>   	struct i3c_bus bus;
>   	struct workqueue_struct *wq;
> +	acpi_handle ahandle;
>   };
>   
>   /**

Re: [PATCH v2 3/6] i3c: master: Add ACPI support to i3c subsystem

Posted by Shyam Sundar S K 2 weeks, 5 days ago


On 11/4/2024 19:36, Jarkko Nikula wrote:
> Hi
> 
> + linux-acpi
> 
> On 10/23/24 8:51 AM, Shyam Sundar S K wrote:
>> As of now, the I3C subsystem only has ARM-specific initialization, and
>> there is no corresponding ACPI plumbing present. To address this, ACPI
>> support needs to be added to both the I3C core and DW driver.
>>
>> Add support to get the ACPI handle from the _HID probed and parse
>> the apci
>> object to retrieve the slave information from BIOS.
>>
>> Based on the acpi object information propogated via BIOS, build the i3c
>> board information so that the same information can be used across the
>> driver to handle the slave requests.
>>
> I think it would be good to have a DSDT example here?

Device (I3CA)
{
	Name (_UID, Zero)  // _UID: Unique ID
	Name (_HID, "AMDI0015")  // _HID: Hardware ID
	Method (_CRS, 0, Serialized)  // _CRS: Current Resource Settings
	{
		Name (BUF0, ResourceTemplate ()
		{
			Interrupt (ResourceConsumer, Edge, ActiveHigh, Exclusive, ,, _Y2C)
			{
				0x0000000A,
			}
			Memory32Fixed (ReadWrite,
				0xFEDD2000,         // Address Base
				0x00001000,         // Address Length
				)
		})
		...
	}

	...
}


> 
>> Co-developed-by: Sanket Goswami <Sanket.Goswami@amd.com>
>> Signed-off-by: Sanket Goswami <Sanket.Goswami@amd.com>
>> Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
>> ---
>>   drivers/i3c/internals.h            |  2 +
>>   drivers/i3c/master.c               | 84
>> ++++++++++++++++++++++++++++++
>>   drivers/i3c/master/dw-i3c-master.c |  7 +++
>>   include/linux/i3c/master.h         |  1 +
>>   4 files changed, 94 insertions(+)
>>
>> diff --git a/drivers/i3c/internals.h b/drivers/i3c/internals.h
>> index 433f6088b7ce..d2d6c69b19dd 100644
>> --- a/drivers/i3c/internals.h
>> +++ b/drivers/i3c/internals.h
>> @@ -10,6 +10,8 @@
>>     #include <linux/i3c/master.h>
>>   +#define AMD_I3C_GET_SLAVE_ADDR        0x30
>> +
>>   void i3c_bus_normaluse_lock(struct i3c_bus *bus);
>>   void i3c_bus_normaluse_unlock(struct i3c_bus *bus);
>>   diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
>> index 6f3eb710a75d..7d23c32e1c0f 100644
>> --- a/drivers/i3c/master.c
>> +++ b/drivers/i3c/master.c
>> @@ -2251,6 +2251,84 @@ static int of_i3c_master_add_dev(struct
>> i3c_master_controller *master,
>>       return ret;
>>   }
>>   +#if IS_ENABLED(CONFIG_ACPI)
>> +static int i3c_acpi_configure_master(struct i3c_master_controller
>> *master)
>> +{
>> +    struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
>> +    enum i3c_addr_slot_status addrstatus;
>> +    struct i3c_dev_boardinfo *boardinfo;
>> +    struct device *dev = &master->dev;
>> +    struct fwnode_handle *fwnode;
>> +    struct acpi_device *adev;
>> +    u32 slv_addr, num_dev;
>> +    acpi_status status;
>> +    u64 val;
>> +
>> +    status = acpi_evaluate_object_typed(master->ahandle, "_DSD",
>> NULL, &buf, ACPI_TYPE_PACKAGE);
>> +    if (ACPI_FAILURE(status)) {
>> +        dev_err(&master->dev, "Error reading _DSD:%s\n",
>> acpi_format_exception(status));
>> +        return -ENODEV;
>> +    }
>> +
>> +    num_dev = device_get_child_node_count(dev);
>> +    if (!num_dev) {
>> +        dev_err(&master->dev, "Error: no child node present\n");
>> +        return -EINVAL;
>> +    }
>> +
>> +    device_for_each_child_node(dev, fwnode) {
>> +        adev = to_acpi_device_node(fwnode);
>> +        if (!adev)
>> +            return -ENODEV;
>> +
>> +        status = acpi_evaluate_integer(adev->handle, "_ADR", NULL,
>> &val);
>> +        if (ACPI_FAILURE(status)) {
>> +            dev_err(&master->dev, "Error: eval _ADR failed\n");
>> +            return -EINVAL;
>> +        }
>> +        slv_addr = val >> AMD_I3C_GET_SLAVE_ADDR;
> 
> This doesn't seem to match with ACPI 6.5 spec [1] chapter 6.1.1 _ADR
> (Address)? Address encoding for I3C says:
> 
> Bits [63:52] - Reserved
> Bits [51:48] - Master Instance
> Bits [47:0] - I3C Device Provisional ID, following encoding defined in
> the MIPI
> Specification for I3C.
> If an I3C device supports a static address instead of a Provisional
> ID, then bits
> [47:7] are Reserved (zero), and bits [6:0] are the 7-bit static address.
> 
> 1. https://uefi.org/sites/default/files/resources/ACPI_Spec_6_5_Aug29.pdf
> 

        Device (SPD0)
        {
            Name (_ADR, 0x005003C000000000)  // _ADR: Address
            Name (_DSD, Package (0x02)  // _DSD: Device-Specific Data
            {
                ToUUID ("e7a40010-1da5-46de-abd0-317a8babc96e") /*
Unknown UUID */,
                Package (0x04)
                {
                    "mipi-i3c-sw-interface-revision",
                    0x00010000,
                    "mipi-i3c-static-address",
                    0x50
                }
            })
        }

if you look at this _ADR, 0x50 is the static address given via the ASL
to the driver and the rest of it is the PID.

You intend to say, the static address bits are incorrectly given by BIOS?

Thanks,
Shyam

>> +
>> +        boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
>> +        if (!boardinfo)
>> +            return -ENOMEM;
>> +
>> +        if (slv_addr) {
>> +            if (slv_addr > I3C_MAX_ADDR)
>> +                return -EINVAL;
>> +
>> +            addrstatus = i3c_bus_get_addr_slot_status(&master->bus,
>> slv_addr);
>> +            if (addrstatus != I3C_ADDR_SLOT_FREE)
>> +                return -EINVAL;
>> +        }
>> +
>> +        boardinfo->static_addr = slv_addr;
>> +        if (boardinfo->static_addr > I3C_MAX_ADDR)
>> +            return -EINVAL;
>> +
>> +        addrstatus = i3c_bus_get_addr_slot_status(&master->bus,   
>> boardinfo->static_addr);
>> +        if (addrstatus != I3C_ADDR_SLOT_FREE)
>> +            return -EINVAL;
>> +
>> +        boardinfo->pid = (val & GENMASK(47, 0));
>> +        if ((boardinfo->pid & GENMASK_ULL(63, 48)) ||
>> +            I3C_PID_RND_LOWER_32BITS(boardinfo->pid))
>> +            return -EINVAL;
>> +
>> +        /*
>> +         * According to the specification, SETDASA is not supported
>> for DIMM slaves
>> +         * during device discovery. Therefore, AMD BIOS will
>> populate same initial
>> +         * dynamic address as the static address.
>> +         */
>> +        boardinfo->init_dyn_addr = boardinfo->static_addr;
>> +        list_add_tail(&boardinfo->node, &master->boardinfo.i3c);
>> +    }
>> +
>> +    return 0;
>> +}
>> +#else
>> +static int i3c_acpi_configure_master(struct i3c_master_controller
>> *master) { return 0; }
>> +#endif
>> +
>>   static int of_populate_i3c_bus(struct i3c_master_controller *master)
>>   {
>>       struct device *dev = &master->dev;
>> @@ -2771,6 +2849,12 @@ int i3c_master_register(struct
>> i3c_master_controller *master,
>>       master->dev.coherent_dma_mask = parent->coherent_dma_mask;
>>       master->dev.dma_parms = parent->dma_parms;
>>   +    if (has_acpi_companion(master->dev.parent)) {
>> +        ret = i3c_acpi_configure_master(master);
>> +        if (ret < 0)
>> +            return ret;
>> +    }
>> +
>>       ret = of_populate_i3c_bus(master);
>>       if (ret)
>>           goto err_put_dev;
>> diff --git a/drivers/i3c/master/dw-i3c-master.c
>> b/drivers/i3c/master/dw-i3c-master.c
>> index fd58a95ae1c3..f683e2a398ad 100644
>> --- a/drivers/i3c/master/dw-i3c-master.c
>> +++ b/drivers/i3c/master/dw-i3c-master.c
>> @@ -1602,6 +1602,13 @@ int dw_i3c_common_probe(struct dw_i3c_master
>> *master,
>>       master->maxdevs = ret >> 16;
>>       master->free_pos = GENMASK(master->maxdevs - 1, 0);
>>   +#if IS_ENABLED(CONFIG_ACPI)
>> +    ACPI_COMPANION_SET(&master->base.dev, ACPI_COMPANION(&pdev->dev));
>> +    master->base.ahandle =
>> acpi_device_handle(ACPI_COMPANION(&pdev->dev));
>> +    if (!master->base.ahandle)
>> +        dev_err(&pdev->dev, "Failed to get acpi device handle\n");
>> +#endif
>> +
>>       INIT_WORK(&master->hj_work, dw_i3c_hj_work);
>>       ret = i3c_master_register(&master->base, &pdev->dev,
>>                     &dw_mipi_i3c_ops, false);
>> diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
>> index 2a1ed05d5782..367faf7c4bf3 100644
>> --- a/include/linux/i3c/master.h
>> +++ b/include/linux/i3c/master.h
>> @@ -523,6 +523,7 @@ struct i3c_master_controller {
>>       } boardinfo;
>>       struct i3c_bus bus;
>>       struct workqueue_struct *wq;
>> +    acpi_handle ahandle;
>>   };
>>     /**
>

[PATCH v2 1/6] i3c: dw: Add support for AMDI0015 ACPI ID
[PATCH v2 2/6] i3c: dw: Use IRQF_SHARED flag for dw-i3c-master
[PATCH v2 3/6] i3c: master: Add ACPI support to i3c subsystem
[PATCH v2 4/6] i3c: master: Add a routine to include the I3C SPD device
[PATCH v2 5/6] i3c: master: Add support for SETAASA CCC
[PATCH v2 6/6] i3c: dw: Add quirk to address OD/PP timing issue on AMD platform