Commit f7f15fc5 authored by Niklas Cassel's avatar Niklas Cassel Committed by Bjorn Helgaas
Browse files

PCI: endpoint: Align pci_epc_get_msi(), pci_epc_ops::get_msi() return value encoding 



The kdoc for API pci_epc_get_msi() says:
"Invoke to get the number of MSI interrupts allocated by the RC"

The kdoc for the callback pci_epc_ops::get_msi() says:
"ops to get the number of MSI interrupts allocated by the RC from
the MSI capability register"

pci_epc_ops::get_msi() does however return the number of interrupts in the
encoding as defined by the Multiple Message Enable (MME) field of the MSI
Capability structure.

Nowhere in the kdoc does it say that the returned number of interrupts is
in MME encoding. It is very confusing that the API pci_epc_get_msi() and
the callback function pci_epc_ops::get_msi() don't return the same value.

Clean up the API and the callback function to have the same semantics,
i.e. return the number of interrupts, regardless of the internal encoding
of that value.

[bhelgaas: more specific subject]

Signed-off-by: default avatarNiklas Cassel <cassel@kernel.org>
Signed-off-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Cc: stable+noautosel@kernel.org # this is simply a cleanup
Link: https://patch.msgid.link/20250514074313.283156-11-cassel@kernel.org
parent c8bcb013

drivers/pci/controller/cadence/pcie-cadence-ep.c

+1 −1
Original line number Diff line number Diff line
@@ -262,7 +262,7 @@ static int cdns_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn) 
	 */

	mme = FIELD_GET(PCI_MSI_FLAGS_QSIZE, flags);



	return mme;

	return 1 << mme;

}



static int cdns_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no)

drivers/pci/controller/dwc/pcie-designware-ep.c

+1 −1
Original line number Diff line number Diff line
@@ -532,7 +532,7 @@ static int dw_pcie_ep_get_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no) 


	val = FIELD_GET(PCI_MSI_FLAGS_QSIZE, val);



	return val;

	return 1 << val;

}



static int dw_pcie_ep_set_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no,

drivers/pci/controller/pcie-rcar-ep.c

+1 −1
Original line number Diff line number Diff line
@@ -280,7 +280,7 @@ static int rcar_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn) 
	if (!(flags & MSICAP0_MSIE))

		return -EINVAL;



	return ((flags & MSICAP0_MMESE_MASK) >> MSICAP0_MMESE_OFFSET);

	return 1 << ((flags & MSICAP0_MMESE_MASK) >> MSICAP0_MMESE_OFFSET);

}



static int rcar_pcie_ep_map_addr(struct pci_epc *epc, u8 fn, u8 vfn,

drivers/pci/controller/pcie-rockchip-ep.c

+2 −2
Original line number Diff line number Diff line
@@ -340,7 +340,7 @@ static int rockchip_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn) 
	if (!(flags & ROCKCHIP_PCIE_EP_MSI_CTRL_ME))

		return -EINVAL;



	return ((flags & ROCKCHIP_PCIE_EP_MSI_CTRL_MME_MASK) >>

	return 1 << ((flags & ROCKCHIP_PCIE_EP_MSI_CTRL_MME_MASK) >>

		     ROCKCHIP_PCIE_EP_MSI_CTRL_MME_OFFSET);

}

drivers/pci/endpoint/pci-epc-core.c

+0 −2
Original line number Diff line number Diff line
@@ -293,8 +293,6 @@ int pci_epc_get_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no) 
	if (interrupt < 0)

		return 0;



	interrupt = 1 << interrupt;



	return interrupt;

}

EXPORT_SYMBOL_GPL(pci_epc_get_msi);