[PATCH 08/13] i3c: mipi-i3c-hci-pci: Allocate a structure for mipi_i3c_hci_pci device information

[Frank Li]

On Thu, Nov 13, 2025 at 03:15:34PM +0200, Adrian Hunter wrote:
> On 12/11/2025 22:17, Frank Li wrote:
> > On Wed, Nov 12, 2025 at 09:25:14PM +0200, Adrian Hunter wrote:
> >> On 12/11/2025 18:41, Frank Li wrote:
> >>> On Wed, Nov 12, 2025 at 12:03:34PM +0200, Adrian Hunter wrote:
> >>>> Allocate a structure for mipi_i3c_hci_pci device information, in
> >>>> preparation for additional changes that need to store mipi_i3c_hci_pci
> >>>> device-specific information.
> >>>>
> >>>> Signed-off-by: Adrian Hunter <adrian.hunter at intel.com>
> >>>> ---
> >>>>  .../master/mipi-i3c-hci/mipi-i3c-hci-pci.c    | 29 ++++++++++++-------
> >>>>  1 file changed, 19 insertions(+), 10 deletions(-)
> >>>>
> >>>> 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 b3b6b6f43af2..9fa89af7479f 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
> >>>> @@ -14,6 +14,10 @@
> >>>>  #include <linux/pci.h>
> >>>>  #include <linux/platform_device.h>
> >>>>
> >>>> +struct mipi_i3c_hci_pci {
> >>>> +	struct platform_device *pdev;
> >>>> +};
> >>>> +
> >>>
> >>> Is it simpler by using platform_device_register_data(), pass down platform
> >>> related information by void *data?
> >>
> >> No, this is just a normal allocated structure for the PCI driver
> >> (mipi_i3c_hci_pci) to put information related to the PCI device.
> >> It is later used to store the current Latency Tolerance Reporting (LTR)
> >> register values.
> >
> > Is it static value, or does it change after boot in other words?
>
> Dynamic
>
> >
> >>
> >> So it is not the same thing as platform_data.
> >
> > Base on your code to create platform data is duplicate what's did by
> > platform_device_register_data().
>
> It is not platform data

I understand 'mipi_i3c_hci_pci' now.
I think you still use platform_device_register_data() to simple your code.

But need seperate patch to do it.

Reviewed-by: Frank Li <Frank.Li at nxp.com>

>
> >
> > The pci device create platform devices,  platform driver should not use
> > pci's information directly. platform driver should be reused if it probe
> > from acpi or dt-tree.
> >
> > I think it'd better pass down platform data information, which can include
> > callback to fetch needed information for difference's parent devices.
>
> PCI Latency Tolerance Reporting (LTR) has nothing to do with I3C
> or the platform device, so it does not belong in the platform driver.
>
> >
> > Frank
> >
> >>
> >>>
> >>> Frank
> >>>>  struct mipi_i3c_hci_pci_info {
> >>>>  	int (*init)(struct pci_dev *pci);
> >>>>  };
> >>>> @@ -71,10 +75,14 @@ static int mipi_i3c_hci_pci_probe(struct pci_dev *pci,
> >>>>  				  const struct pci_device_id *id)
> >>>>  {
> >>>>  	const struct mipi_i3c_hci_pci_info *info;
> >>>> -	struct platform_device *pdev;
> >>>> +	struct mipi_i3c_hci_pci *hci;
> >>>>  	struct resource res[2];
> >>>>  	int dev_id, ret;
> >>>>
> >>>> +	hci = devm_kzalloc(&pci->dev, sizeof(*hci), GFP_KERNEL);
> >>>> +	if (!hci)
> >>>> +		return -ENOMEM;
> >>>> +
> >>>>  	ret = pcim_enable_device(pci);
> >>>>  	if (ret)
> >>>>  		return ret;
> >>>> @@ -95,14 +103,14 @@ static int mipi_i3c_hci_pci_probe(struct pci_dev *pci,
> >>>>  	if (dev_id < 0)
> >>>>  		return dev_id;
> >>>>
> >>>> -	pdev = platform_device_alloc("mipi-i3c-hci", dev_id);
> >>>> -	if (!pdev)
> >>>> +	hci->pdev = platform_device_alloc("mipi-i3c-hci", dev_id);
> >>>> +	if (!hci->pdev)
> >>>>  		return -ENOMEM;
> >>>>
> >>>> -	pdev->dev.parent = &pci->dev;
> >>>> -	device_set_node(&pdev->dev, dev_fwnode(&pci->dev));
> >>>> +	hci->pdev->dev.parent = &pci->dev;
> >>>> +	device_set_node(&hci->pdev->dev, dev_fwnode(&pci->dev));
> >>>>
> >>>> -	ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res));
> >>>> +	ret = platform_device_add_resources(hci->pdev, res, ARRAY_SIZE(res));
> >>>>  	if (ret)
> >>>>  		goto err;
> >>>>
> >>>> @@ -113,23 +121,24 @@ static int mipi_i3c_hci_pci_probe(struct pci_dev *pci,
> >>>>  			goto err;
> >>>>  	}
> >>>>
> >>>> -	ret = platform_device_add(pdev);
> >>>> +	ret = platform_device_add(hci->pdev);
> >>>>  	if (ret)
> >>>>  		goto err;
> >>>>
> >>>> -	pci_set_drvdata(pci, pdev);
> >>>> +	pci_set_drvdata(pci, hci);
> >>>>
> >>>>  	return 0;
> >>>>
> >>>>  err:
> >>>> -	platform_device_put(pdev);
> >>>> +	platform_device_put(hci->pdev);
> >>>>  	ida_free(&mipi_i3c_hci_pci_ida, dev_id);
> >>>>  	return ret;
> >>>>  }
> >>>>
> >>>>  static void mipi_i3c_hci_pci_remove(struct pci_dev *pci)
> >>>>  {
> >>>> -	struct platform_device *pdev = pci_get_drvdata(pci);
> >>>> +	struct mipi_i3c_hci_pci *hci = pci_get_drvdata(pci);
> >>>> +	struct platform_device *pdev = hci->pdev;
> >>>>  	int dev_id = pdev->id;
> >>>>
> >>>>  	platform_device_unregister(pdev);
> >>>> --
> >>>> 2.51.0
> >>>>
> >>>>
> >>>> --
> >>>> linux-i3c mailing list
> >>>> linux-i3c at lists.infradead.org
> >>>> http://lists.infradead.org/mailman/listinfo/linux-i3c
> >>
> >>
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>
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