[ Upstream commit
421db1ab287eebe80fd203eb009ae92836c586ad ]
commit
beb4641a787d ("PCI: dwc: Add MSI-X callbacks handler") while
adding MSI-X callback handler, introduced dw_pcie_ep_find_capability()
and __dw_pcie_ep_find_next_cap() for finding the MSI and MSIX capability.
However if MSI or MSIX capability is the last capability (i.e there are
no additional items in the capabilities list and the Next Capability
Pointer is set to '0'), __dw_pcie_ep_find_next_cap will return '0'
even though MSI or MSIX capability may be present because of
incorrect ordering of the "next_cap_ptr" check. Fix it.
Fixes:
beb4641a787d ("PCI: dwc: Add MSI-X callbacks handler")
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
u8 cap_id, next_cap_ptr;
u16 reg;
+ if (!cap_ptr)
+ return 0;
+
reg = dw_pcie_readw_dbi(pci, cap_ptr);
- next_cap_ptr = (reg & 0xff00) >> 8;
cap_id = (reg & 0x00ff);
- if (!next_cap_ptr || cap_id > PCI_CAP_ID_MAX)
+ if (cap_id > PCI_CAP_ID_MAX)
return 0;
if (cap_id == cap)
return cap_ptr;
+ next_cap_ptr = (reg & 0xff00) >> 8;
return __dw_pcie_ep_find_next_cap(pci, next_cap_ptr, cap);
}
reg = dw_pcie_readw_dbi(pci, PCI_CAPABILITY_LIST);
next_cap_ptr = (reg & 0x00ff);
- if (!next_cap_ptr)
- return 0;
-
return __dw_pcie_ep_find_next_cap(pci, next_cap_ptr, cap);
}