[PATCH V3 06/11] i3c: mipi-i3c-hci-pci: Assign unique device names and IDs for Intel LPSS I3C

Adrian Hunter adrian.hunter at intel.com
Tue Dec 16 09:14:38 PST 2025


On 16/12/2025 19:08, Frank Li wrote:
> On Tue, Dec 16, 2025 at 06:56:37PM +0200, Adrian Hunter wrote:
>> Simplify the code and ensure names and IDs align with device documentation.
>> Use explicit device names and IDs for Intel LPSS I3C controllers instead of
>> dynamically allocated values.
>>
>> Add "intel-lpss-i3c" to the platform_device_id table in the mipi-i3c-hci
>> driver and use the same name for Intel I3C controllers in the
>> mipi_i3c_hci_pci driver.  Assign hard-coded IDs to reflect the hardware
>> layout.
>>
>> Intel SoCs include two I3C PCI devices in the Low Power Subsystem (LPSS),
>> each supporting up to two I3C buses. The second PCI device is assigned ID 2
>> (not 1) to match this topology.  Additional IDs will be introduced when
>> Multi-Bus Instance support is implemented.
>>
>> Signed-off-by: Adrian Hunter <adrian.hunter at intel.com>
>> ---
>>
>>
>> Change in V3:
>>
>> 	New patch
>>
>>
>>  drivers/i3c/master/mipi-i3c-hci/core.c        |  7 +++
>>  .../master/mipi-i3c-hci/mipi-i3c-hci-pci.c    | 43 ++++++++++---------
>>  2 files changed, 30 insertions(+), 20 deletions(-)
>>
>> diff --git a/drivers/i3c/master/mipi-i3c-hci/core.c b/drivers/i3c/master/mipi-i3c-hci/core.c
>> index 07fb91a12593..3d6544a64188 100644
>> --- a/drivers/i3c/master/mipi-i3c-hci/core.c
>> +++ b/drivers/i3c/master/mipi-i3c-hci/core.c
>> @@ -790,9 +790,16 @@ static const struct acpi_device_id i3c_hci_acpi_match[] = {
>>  };
>>  MODULE_DEVICE_TABLE(acpi, i3c_hci_acpi_match);
>>
>> +static const struct platform_device_id i3c_hci_driver_ids[] = {
>> +	{ .name = "intel-lpss-i3c" },
>> +	{ /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(platform, i3c_hci_driver_ids);
>> +
>>  static struct platform_driver i3c_hci_driver = {
>>  	.probe = i3c_hci_probe,
>>  	.remove = i3c_hci_remove,
>> +	.id_table = i3c_hci_driver_ids,
>>  	.driver = {
>>  		.name = "mipi-i3c-hci",
>>  		.of_match_table = of_match_ptr(i3c_hci_of_match),
>> diff --git a/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c b/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c
>> index 0fd3587671e1..3b319fbf18ce 100644
>> --- a/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c
>> +++ b/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c
>> @@ -27,10 +27,10 @@ struct mipi_i3c_hci_pci {
>>  struct mipi_i3c_hci_pci_info {
>>  	int (*init)(struct mipi_i3c_hci_pci *hci);
>>  	void (*exit)(struct mipi_i3c_hci_pci *hci);
>> +	const char *name;
>> +	int id;
>>  };
>>
>> -static DEFINE_IDA(mipi_i3c_hci_pci_ida);
>> -
>>  #define INTEL_PRIV_OFFSET		0x2b0
>>  #define INTEL_PRIV_SIZE			0x28
>>  #define INTEL_RESETS			0x04
>> @@ -179,9 +179,18 @@ static void intel_i3c_exit(struct mipi_i3c_hci_pci *hci)
>>  	intel_ltr_hide(&hci->pci->dev);
>>  }
>>
>> -static const struct mipi_i3c_hci_pci_info intel_info = {
>> +static const struct mipi_i3c_hci_pci_info intel_1_info = {
>>  	.init = intel_i3c_init,
>>  	.exit = intel_i3c_exit,
>> +	.name = "intel-lpss-i3c",
>> +	.id = 0,
>> +};
>> +
>> +static const struct mipi_i3c_hci_pci_info intel_2_info = {
>> +	.init = intel_i3c_init,
>> +	.exit = intel_i3c_exit,
>> +	.name = "intel-lpss-i3c",
>> +	.id = 2,
>>  };
>>
>>  static int mipi_i3c_hci_pci_probe(struct pci_dev *pci,
>> @@ -189,7 +198,7 @@ static int mipi_i3c_hci_pci_probe(struct pci_dev *pci,
>>  {
>>  	struct mipi_i3c_hci_pci *hci;
>>  	struct resource res[2];
>> -	int dev_id, ret;
>> +	int ret;
>>
>>  	hci = devm_kzalloc(&pci->dev, sizeof(*hci), GFP_KERNEL);
>>  	if (!hci)
>> @@ -217,11 +226,9 @@ static int mipi_i3c_hci_pci_probe(struct pci_dev *pci,
>>  	res[1].start = pci_irq_vector(hci->pci, 0);
>>  	res[1].end = res[1].start;
>>
>> -	dev_id = ida_alloc(&mipi_i3c_hci_pci_ida, GFP_KERNEL);
>> -	if (dev_id < 0)
>> -		return dev_id;
>> +	hci->info = (const struct mipi_i3c_hci_pci_info *)id->driver_data;
>>
>> -	hci->pdev = platform_device_alloc("mipi-i3c-hci", dev_id);
>> +	hci->pdev = platform_device_alloc(hci->info->name, hci->info->id);
>>  	if (!hci->pdev)
>>  		return -ENOMEM;
>>
>> @@ -232,7 +239,6 @@ static int mipi_i3c_hci_pci_probe(struct pci_dev *pci,
>>  	if (ret)
>>  		goto err;
>>
>> -	hci->info = (const struct mipi_i3c_hci_pci_info *)id->driver_data;
>>  	if (hci->info->init) {
>>  		ret = hci->info->init(hci);
>>  		if (ret)
>> @@ -252,7 +258,6 @@ static int mipi_i3c_hci_pci_probe(struct pci_dev *pci,
>>  		hci->info->exit(hci);
>>  err:
>>  	platform_device_put(hci->pdev);
>> -	ida_free(&mipi_i3c_hci_pci_ida, dev_id);
>>  	return ret;
>>  }
>>
>> @@ -260,28 +265,26 @@ static void mipi_i3c_hci_pci_remove(struct pci_dev *pci)
>>  {
>>  	struct mipi_i3c_hci_pci *hci = pci_get_drvdata(pci);
>>  	struct platform_device *pdev = hci->pdev;
>> -	int dev_id = pdev->id;
>>
>>  	if (hci->info->exit)
>>  		hci->info->exit(hci);
>>
>>  	platform_device_unregister(pdev);
>> -	ida_free(&mipi_i3c_hci_pci_ida, dev_id);
>>  }
>>
>>  static const struct pci_device_id mipi_i3c_hci_pci_devices[] = {
>>  	/* Wildcat Lake-U */
>> -	{ PCI_VDEVICE(INTEL, 0x4d7c), (kernel_ulong_t)&intel_info},
>> -	{ PCI_VDEVICE(INTEL, 0x4d6f), (kernel_ulong_t)&intel_info},
>> +	{ PCI_VDEVICE(INTEL, 0x4d7c), (kernel_ulong_t)&intel_1_info},
> 
> If there there are two 0x4d7c pcie cards in system, id will be the same.
> Is it okay?

These are not cards.  These PCI device IDs are unique to each device
in the SoC, so duplicate IDs would never happen.

> 
> Frank
> 
>> +	{ PCI_VDEVICE(INTEL, 0x4d6f), (kernel_ulong_t)&intel_2_info},
>>  	/* Panther Lake-H */
>> -	{ PCI_VDEVICE(INTEL, 0xe37c), (kernel_ulong_t)&intel_info},
>> -	{ PCI_VDEVICE(INTEL, 0xe36f), (kernel_ulong_t)&intel_info},
>> +	{ PCI_VDEVICE(INTEL, 0xe37c), (kernel_ulong_t)&intel_1_info},
>> +	{ PCI_VDEVICE(INTEL, 0xe36f), (kernel_ulong_t)&intel_2_info},
>>  	/* Panther Lake-P */
>> -	{ PCI_VDEVICE(INTEL, 0xe47c), (kernel_ulong_t)&intel_info},
>> -	{ PCI_VDEVICE(INTEL, 0xe46f), (kernel_ulong_t)&intel_info},
>> +	{ PCI_VDEVICE(INTEL, 0xe47c), (kernel_ulong_t)&intel_1_info},
>> +	{ PCI_VDEVICE(INTEL, 0xe46f), (kernel_ulong_t)&intel_2_info},
>>  	/* Nova Lake-S */
>> -	{ PCI_VDEVICE(INTEL, 0x6e2c), (kernel_ulong_t)&intel_info},
>> -	{ PCI_VDEVICE(INTEL, 0x6e2d), (kernel_ulong_t)&intel_info},
>> +	{ PCI_VDEVICE(INTEL, 0x6e2c), (kernel_ulong_t)&intel_1_info},
>> +	{ PCI_VDEVICE(INTEL, 0x6e2d), (kernel_ulong_t)&intel_2_info},
>>  	{ },
>>  };
>>  MODULE_DEVICE_TABLE(pci, mipi_i3c_hci_pci_devices);
>> --
>> 2.51.0
>>
>>
>> --
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