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>

diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index 538bbf310e44761359aabca75e271ecee7966e22..12c42fcd7c3528298f2e195886382d215ab05942 100644 (file)
--- 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);