IB/hfi1: Convert PCIBIOS_* errors to generic -E* errors

pcie_speeds() and restore_pci_variables() returns PCIBIOS_ error codes
from PCIe capability accessors.

PCIBIOS_ error codes have positive values. Passing on these values is
inconsistent with functions which return only a negative value on failure.

Before passing on the return value of PCIe capability accessors, call
pcibios_err_to_errno() to convert any positive PCIBIOS_ error codes to
negative generic error values.

Link: https://lore.kernel.org/r/20200615073225.24061-3-refactormyself@gmail.comSuggested-by: Bjorn Helgaas <bjorn@helgaas.com>
Signed-off-by: Bolarinwa Olayemi Saheed <refactormyself@gmail.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/hw/hfi1/pcie.c

@@ -306,7 +306,7 @@ int pcie_speeds(struct hfi1_devdata *dd)
 	ret = pcie_capability_read_dword(dd->pcidev, PCI_EXP_LNKCAP, &linkcap);
 	if (ret) {
 		dd_dev_err(dd, "Unable to read from PCI config\n");
-		return ret;
+		return pcibios_err_to_errno(ret);
 	}
 
 	if ((linkcap & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_8_0GB) {
@@ -334,10 +334,14 @@ int pcie_speeds(struct hfi1_devdata *dd)
 	return 0;
 }
 
-/* restore command and BARs after a reset has wiped them out */
+/**
+ * Restore command and BARs after a reset has wiped them out
+ *
+ * Returns 0 on success, otherwise a negative error value
+ */
 int restore_pci_variables(struct hfi1_devdata *dd)
 {
-	int ret = 0;
+	int ret;
 
 	ret = pci_write_config_word(dd->pcidev, PCI_COMMAND, dd->pci_command);
 	if (ret)
@@ -386,13 +390,17 @@ int restore_pci_variables(struct hfi1_devdata *dd)
 
 error:
 	dd_dev_err(dd, "Unable to write to PCI config\n");
-	return ret;
+	return pcibios_err_to_errno(ret);
 }
 
-/* Save BARs and command to rewrite after device reset */
+/**
+ * Save BARs and command to rewrite after device reset
+ *
+ * Returns 0 on success, otherwise a negative error value
+ */
 int save_pci_variables(struct hfi1_devdata *dd)
 {
-	int ret = 0;
+	int ret;
 
 	ret = pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0,
 				    &dd->pcibar0);
@@ -441,7 +449,7 @@ int save_pci_variables(struct hfi1_devdata *dd)
 
 error:
 	dd_dev_err(dd, "Unable to read from PCI config\n");
-	return ret;
+	return pcibios_err_to_errno(ret);
 }
 
 /*