Subject: [PATCH dwc-next 1/3] PCI: dwc: Don't assume the ops in dw_pcie always exists

From: Jisheng Zhang <[email-masked]>
Date: Mon, 5 Oct 2020 16:57:33 +0800

Some designware based device driver especially host only driver may
work well with the default read_dbi/write_dbi/link_up implementation
in pcie-designware.c, thus remove the assumption to simplify those
drivers.

Signed-off-by: Jisheng Zhang <[email-masked]>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c |  8 +++-----
 drivers/pci/controller/dwc/pcie-designware.c    | 14 +++++++-------
 2 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index ad7da4ea43a5..411b7624331d 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -432,10 +432,8 @@ static void dw_pcie_ep_stop(struct pci_epc *epc)
 	struct dw_pcie_ep *ep = epc_get_drvdata(epc);
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
 
-	if (!pci->ops->stop_link)
-		return;
-
-	pci->ops->stop_link(pci);
+	if (pci->ops && pci->ops->stop_link)
+		pci->ops->stop_link(pci);
 }
 
 static int dw_pcie_ep_start(struct pci_epc *epc)
@@ -443,7 +441,7 @@ static int dw_pcie_ep_start(struct pci_epc *epc)
 	struct dw_pcie_ep *ep = epc_get_drvdata(epc);
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
 
-	if (!pci->ops->start_link)
+	if (!pci->ops || !pci->ops->start_link)
 		return -EINVAL;
 
 	return pci->ops->start_link(pci);
diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 3c1f17c78241..2a6109109029 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -140,7 +140,7 @@ u32 dw_pcie_read_dbi(struct dw_pcie *pci, u32 reg, size_t size)
 	int ret;
 	u32 val;
 
-	if (pci->ops->read_dbi)
+	if (pci->ops && pci->ops->read_dbi)
 		return pci->ops->read_dbi(pci, pci->dbi_base, reg, size);
 
 	ret = dw_pcie_read(pci->dbi_base + reg, size, &val);
@@ -155,7 +155,7 @@ void dw_pcie_write_dbi(struct dw_pcie *pci, u32 reg, size_t size, u32 val)
 {
 	int ret;
 
-	if (pci->ops->write_dbi) {
+	if (pci->ops && pci->ops->write_dbi) {
 		pci->ops->write_dbi(pci, pci->dbi_base, reg, size, val);
 		return;
 	}
@@ -170,7 +170,7 @@ void dw_pcie_write_dbi2(struct dw_pcie *pci, u32 reg, size_t size, u32 val)
 {
 	int ret;
 
-	if (pci->ops->write_dbi2) {
+	if (pci->ops && pci->ops->write_dbi2) {
 		pci->ops->write_dbi2(pci, pci->dbi_base2, reg, size, val);
 		return;
 	}
@@ -185,7 +185,7 @@ static u32 dw_pcie_readl_atu(struct dw_pcie *pci, u32 reg)
 	int ret;
 	u32 val;
 
-	if (pci->ops->read_dbi)
+	if (pci->ops && pci->ops->read_dbi)
 		return pci->ops->read_dbi(pci, pci->atu_base, reg, 4);
 
 	ret = dw_pcie_read(pci->atu_base + reg, 4, &val);
@@ -199,7 +199,7 @@ static void dw_pcie_writel_atu(struct dw_pcie *pci, u32 reg, u32 val)
 {
 	int ret;
 
-	if (pci->ops->write_dbi) {
+	if (pci->ops && pci->ops->write_dbi) {
 		pci->ops->write_dbi(pci, pci->atu_base, reg, 4, val);
 		return;
 	}
@@ -270,7 +270,7 @@ static void __dw_pcie_prog_outbound_atu(struct dw_pcie *pci, u8 func_no,
 {
 	u32 retries, val;
 
-	if (pci->ops->cpu_addr_fixup)
+	if (pci->ops && pci->ops->cpu_addr_fixup)
 		cpu_addr = pci->ops->cpu_addr_fixup(pci, cpu_addr);
 
 	if (pci->iatu_unroll_enabled) {
@@ -478,7 +478,7 @@ int dw_pcie_link_up(struct dw_pcie *pci)
 {
 	u32 val;
 
-	if (pci->ops->link_up)
+	if (pci->ops && pci->ops->link_up)
 		return pci->ops->link_up(pci);
 
 	val = readl(pci->dbi_base + PCIE_PORT_DEBUG1);
-- 
2.28.0

_______________________________________________
linux-arm-kernel mailing list
[email-masked]
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel