PCI: designware: Check private_data validity in single place

The driver had checks for this sprinkled all over.  As we call
sys_to_pcie() before every instance of this check, we can move the
check to this single location to make things clear.

Removing the statements after BUG[_ON]() is safe as the kernel is halted at
this point anyway.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Mohit Kumar <mohit.kumar@st.com>

1 files changed, 2 insertions, 27 deletions

diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index 538bbf310e44..12c42fcd7c35 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -73,6 +73,8 @@ static unsigned long global_io_offset;
 
 static inline struct pcie_port *sys_to_pcie(struct pci_sys_data *sys)
 {
+        BUG_ON(!sys->private_data);
+
         return sys->private_data;
 }
 
@@ -261,11 +263,6 @@ static int assign_irq(int no_irqs, struct msi_desc *desc, int *pos)
         int irq, pos0, pos1, i;
         struct pcie_port *pp = sys_to_pcie(desc->dev->bus->sysdata);
 
-        if (!pp) {
-                BUG();
-                return -EINVAL;
-        }
-
         pos0 = find_first_zero_bit(pp->msi_irq_in_use,
                         MAX_MSI_IRQS);
         if (pos0 % no_irqs) {
@@ -326,10 +323,6 @@ static void clear_irq(unsigned int irq)
         /* get the port structure */
         msi = irq_data_get_msi(data);
         pp = sys_to_pcie(msi->dev->bus->sysdata);
-        if (!pp) {
-                BUG();
-                return;
-        }
 
         /* undo what was done in assign_irq */
         pos = data->hwirq;
@@ -350,11 +343,6 @@ static int dw_msi_setup_irq(struct msi_chip *chip, struct pci_dev *pdev,
         struct msi_msg msg;
         struct pcie_port *pp = sys_to_pcie(pdev->bus->sysdata);
 
-        if (!pp) {
-                BUG();
-                return -EINVAL;
-        }
-
         pci_read_config_word(pdev, desc->msi_attrib.pos+PCI_MSI_FLAGS,
                                 &msg_ctr);
         msgvec = (msg_ctr&PCI_MSI_FLAGS_QSIZE) >> 4;
@@ -729,11 +717,6 @@ static int dw_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
         struct pcie_port *pp = sys_to_pcie(bus->sysdata);
         int ret;
 
-        if (!pp) {
-                BUG();
-                return -EINVAL;
-        }
-
         if (dw_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0) {
                 *val = 0xffffffff;
                 return PCIBIOS_DEVICE_NOT_FOUND;
@@ -758,11 +741,6 @@ static int dw_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
         struct pcie_port *pp = sys_to_pcie(bus->sysdata);
         int ret;
 
-        if (!pp) {
-                BUG();
-                return -EINVAL;
-        }
-
         if (dw_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0)
                 return PCIBIOS_DEVICE_NOT_FOUND;
 
@@ -790,9 +768,6 @@ static int dw_pcie_setup(int nr, struct pci_sys_data *sys)
 
         pp = sys_to_pcie(sys);
 
-        if (!pp)
-                return 0;
-
         if (global_io_offset < SZ_1M && pp->config.io_size > 0) {
                 sys->io_offset = global_io_offset - pp->config.io_bus_addr;
                 pci_ioremap_io(global_io_offset, pp->io_base);