Re: [PATCH] pci: pcie-rcar: add regulators support

[Bjorn Helgaas <helgaas@kernel.org>]

On Tue, Oct 19, 2021 at 05:58:58PM +0800, Meng Li wrote:
> From: Andrey Gusakov <andrey.gusakov@cogentembedded.com>
> 
> Add PCIe regulators for KingFisher board.

Please pay attention to the existing code and history.  Your current
subject line is:

  pci: pcie-rcar: add regulators support

which looks nothing like the history:

  $ git log --oneline drivers/pci/controller/pcie-rcar-host.c
  861e133ba268 ("PCI: rcar-host: Remove unneeded includes")
  a115b1bd3af0 ("PCI: rcar: Add L1 link state fix into data abort hook")
  d21faba11693 ("PCI: Bulk conversion to generic_handle_domain_irq()")
  83ed8d4fa656 ("PCI: rcar: Convert to MSI domains")
  93cd1bb4862d ("PCI: rcar: Don't allocate extra memory for the MSI capture address")
  c4e0fec2f7ee ("PCI: rcar: Always allocate MSI addresses in 32bit space")
  6e8e137abeab ("PCI: rcar: Drop unused members from struct rcar_pcie_host")
  b64aa11eb2dd ("PCI: Set bridge map_irq and swizzle_irq to default functions")
  669cbc708122 ("PCI: Move DT resource setup into devm_pci_alloc_host_bridge()")
  b411b2e1adb9 ("PCI: rcar: Use struct pci_host_bridge.windows list directly")
  61f11f8250e2 ("PCI: rcar: Use devm_pci_alloc_host_bridge()")
  4f5c883d7815 ("PCI: Move setting pci_host_bridge.busnr out of host drivers")
  6176a5f32751 ("PCI: rcar: Use pci_is_root_bus() to check if bus is root bus")
  6a589900d050 ("PCI: Set default bridge parent device")
  a68e06e729b1 ("PCI: rcar: Fix runtime PM imbalance on error")
  56d292348470 ("PCI: rcar: Use pci_host_probe() to register host")
  78a0d7f2f5a3 ("PCI: rcar: Move shareable code to a common file")
  a18f4b6ea50b ("PCI: rcar: Rename pcie-rcar.c to pcie-rcar-host.c")

You could use something like:

  PCI: rcar-host: Add regulator support for KingFisher

> +	host->pcie3v3 = devm_regulator_get_optional(dev, "pcie3v3");
> +	if (IS_ERR(host->pcie3v3)) {

+1 to Geert's comments.  Sprinkling IS_ERR() everywhere is kind of
ugly.  host->pcie3v3 should be NULL if not present.

Bjorn