PCI: dwc: Don't assume the ops in dw_pcie always exist

Some dwc-based device drivers, especially host-only drivers, may work well
with the default read_dbi/write_dbi/link_up implementations in
pcie-designware.c, so remove the assumption that every driver implements
them to simplify those drivers.

Link: https://lore.kernel.org/r/20210128144258.10329aa4@xhacker.debian
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index bcd1cd9..1c25d83 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -434,10 +434,8 @@ 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)
@@ -445,7 +443,7 @@ 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-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index bcb5bd7..0f0d8f4 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -404,7 +404,7 @@ int dw_pcie_host_init(struct pcie_port *pp)
        dw_pcie_setup_rc(pp);
        dw_pcie_msi_init(pp);
 
-       if (!dw_pcie_link_up(pci) && pci->ops->start_link) {
+       if (!dw_pcie_link_up(pci) && pci->ops && pci->ops->start_link) {
                ret = pci->ops->start_link(pci);
                if (ret)
                        goto err_free_msi;

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index fb63783..004cb86 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -141,7 +141,7 @@ 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);
@@ -156,7 +156,7 @@ 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;
        }
@@ -171,7 +171,7 @@ 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;
        }
@@ -186,7 +186,7 @@ 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);
@@ -200,7 +200,7 @@ 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;
        }
@@ -316,7 +316,7 @@ 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) {
@@ -531,7 +531,7 @@ 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);