media: cobalt: Prefer pcie_capability_read_word()

Commit 8c0d3a02 ("PCI: Add accessors for PCI Express Capability")
added accessors for the PCI Express Capability so that drivers didn't
need to be aware of differences between v1 and v2 of the PCI
Express Capability.

Replace pci_read_config_word() and pci_write_config_word() calls with
pcie_capability_read_word() and pcie_capability_write_word().
Signed-off-by: Frederick Lawler <fred@fredlawl.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/pci/cobalt/cobalt-driver.c

@@ -186,20 +186,16 @@ void cobalt_pcie_status_show(struct cobalt *cobalt)
 {
 	struct pci_dev *pci_dev = cobalt->pci_dev;
 	struct pci_dev *pci_bus_dev = cobalt->pci_dev->bus->self;
-	int offset;
-	int bus_offset;
 	u32 capa;
 	u16 stat, ctrl;
 
-	offset = pci_find_capability(pci_dev, PCI_CAP_ID_EXP);
-	bus_offset = pci_find_capability(pci_bus_dev, PCI_CAP_ID_EXP);
-	if (!offset || !bus_offset)
+	if (!pci_is_pcie(pci_dev) || !pci_is_pcie(pci_bus_dev))
 		return;
 
 	/* Device */
-	pci_read_config_dword(pci_dev, offset + PCI_EXP_DEVCAP, &capa);
-	pci_read_config_word(pci_dev, offset + PCI_EXP_DEVCTL, &ctrl);
-	pci_read_config_word(pci_dev, offset + PCI_EXP_DEVSTA, &stat);
+	pcie_capability_read_dword(pci_dev, PCI_EXP_DEVCAP, &capa);
+	pcie_capability_read_word(pci_dev, PCI_EXP_DEVCTL, &ctrl);
+	pcie_capability_read_word(pci_dev, PCI_EXP_DEVSTA, &stat);
 	cobalt_info("PCIe device capability 0x%08x: Max payload %d\n",
 		    capa, get_payload_size(capa & PCI_EXP_DEVCAP_PAYLOAD));
 	cobalt_info("PCIe device control 0x%04x: Max payload %d. Max read request %d\n",
@@ -209,9 +205,9 @@ void cobalt_pcie_status_show(struct cobalt *cobalt)
 	cobalt_info("PCIe device status 0x%04x\n", stat);
 
 	/* Link */
-	pci_read_config_dword(pci_dev, offset + PCI_EXP_LNKCAP, &capa);
-	pci_read_config_word(pci_dev, offset + PCI_EXP_LNKCTL, &ctrl);
-	pci_read_config_word(pci_dev, offset + PCI_EXP_LNKSTA, &stat);
+	pcie_capability_read_dword(pci_dev, PCI_EXP_LNKCAP, &capa);
+	pcie_capability_read_word(pci_dev, PCI_EXP_LNKCTL, &ctrl);
+	pcie_capability_read_word(pci_dev, PCI_EXP_LNKSTA, &stat);
 	cobalt_info("PCIe link capability 0x%08x: %s per lane and %u lanes\n",
 			capa, get_link_speed(capa),
 			(capa & PCI_EXP_LNKCAP_MLW) >> 4);
@@ -221,15 +217,15 @@ void cobalt_pcie_status_show(struct cobalt *cobalt)
 		    (stat & PCI_EXP_LNKSTA_NLW) >> 4);
 
 	/* Bus */
-	pci_read_config_dword(pci_bus_dev, bus_offset + PCI_EXP_LNKCAP, &capa);
+	pcie_capability_read_dword(pci_bus_dev, PCI_EXP_LNKCAP, &capa);
 	cobalt_info("PCIe bus link capability 0x%08x: %s per lane and %u lanes\n",
 			capa, get_link_speed(capa),
 			(capa & PCI_EXP_LNKCAP_MLW) >> 4);
 
 	/* Slot */
-	pci_read_config_dword(pci_dev, offset + PCI_EXP_SLTCAP, &capa);
-	pci_read_config_word(pci_dev, offset + PCI_EXP_SLTCTL, &ctrl);
-	pci_read_config_word(pci_dev, offset + PCI_EXP_SLTSTA, &stat);
+	pcie_capability_read_dword(pci_dev, PCI_EXP_SLTCAP, &capa);
+	pcie_capability_read_word(pci_dev, PCI_EXP_SLTCTL, &ctrl);
+	pcie_capability_read_word(pci_dev, PCI_EXP_SLTSTA, &stat);
 	cobalt_info("PCIe slot capability 0x%08x\n", capa);
 	cobalt_info("PCIe slot control 0x%04x\n", ctrl);
 	cobalt_info("PCIe slot status 0x%04x\n", stat);
@@ -238,26 +234,22 @@ void cobalt_pcie_status_show(struct cobalt *cobalt)
 static unsigned pcie_link_get_lanes(struct cobalt *cobalt)
 {
 	struct pci_dev *pci_dev = cobalt->pci_dev;
-	unsigned offset;
 	u16 link;
 
-	offset = pci_find_capability(pci_dev, PCI_CAP_ID_EXP);
-	if (!offset)
+	if (!pci_is_pcie(pci_dev))
 		return 0;
-	pci_read_config_word(pci_dev, offset + PCI_EXP_LNKSTA, &link);
+	pcie_capability_read_word(pci_dev, PCI_EXP_LNKSTA, &link);
 	return (link & PCI_EXP_LNKSTA_NLW) >> 4;
 }
 
 static unsigned pcie_bus_link_get_lanes(struct cobalt *cobalt)
 {
 	struct pci_dev *pci_dev = cobalt->pci_dev->bus->self;
-	unsigned offset;
 	u32 link;
 
-	offset = pci_find_capability(pci_dev, PCI_CAP_ID_EXP);
-	if (!offset)
+	if (!pci_is_pcie(pci_dev))
 		return 0;
-	pci_read_config_dword(pci_dev, offset + PCI_EXP_LNKCAP, &link);
+	pcie_capability_read_dword(pci_dev, PCI_EXP_LNKCAP, &link);
 	return (link & PCI_EXP_LNKCAP_MLW) >> 4;
 }