PCI: dwc: Verify the single eDMA IRQ in dw_pcie_edma_irq_verify()

dw_pcie_edma_irq_verify() is supposed to verify the eDMA IRQs in devicetree
by fetching them using either 'dma' or 'dmaX' IRQ names. Former is used
when the platform uses a single IRQ for all eDMA channels and latter is
used when the platform uses separate IRQ per channel. But currently,
dw_pcie_edma_irq_verify() bails out early if edma::nr_irqs is 1, i.e., when
a single IRQ is used. This gives an impression that the driver could work
with any single IRQ in devicetree, not necessarily with name 'dma'.

But dw_pcie_edma_irq_vector(), which actually requests the IRQ, does
require the single IRQ to be named as 'dma'. So this creates inconsistency
between dw_pcie_edma_irq_verify() and dw_pcie_edma_irq_vector().

Thus, to fix this inconsistency, make sure dw_pcie_edma_irq_verify() also
verifies the single IRQ name by removing the bail out code.

Signed-off-by: Niklas Cassel <[email protected]>
[mani: reworded subject and description]
Signed-off-by: Manivannan Sadhasivam <[email protected]>
[bhelgaas: fix typos]
Signed-off-by: Bjorn Helgaas <[email protected]>
Link: https://patch.msgid.link/[email protected]

Author: floatious

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

@@ -1045,9 +1045,7 @@ static int dw_pcie_edma_irq_verify(struct dw_pcie *pci)
 	char name[15];
 	int ret;
 
-	if (pci->edma.nr_irqs == 1)
-		return 0;
-	else if (pci->edma.nr_irqs > 1)
+	if (pci->edma.nr_irqs > 1)
 		return pci->edma.nr_irqs != ch_cnt ? -EINVAL : 0;
 
 	ret = platform_get_irq_byname_optional(pdev, "dma");