[v4,09/17] PCI: dwc: dra7xx: Help compiler to remove unused code

Message ID 20171103134722.5532-10-niklas.cassel@axis.com
State Needs Review / ACK
Headers show
Series
  • dwc MSI fixes, ARTPEC-6 EP mode support, ARTPEC-7 SoC support
Related show

Commit Message

Niklas Cassel Nov. 3, 2017, 1:47 p.m.
The dra7xx driver supports both host and ep mode.
When enabling support for only one of the modes, help the compiler
to remove code for the mode that we have not enabled in the driver.

By adding if (!IS_ENABLED(CONFIG_PCI_DRA7XX_HOST)) return -ENODEV;
anything after that statement will get silently dropped by the compiler,
including static functions and structures that are referenced indirectly
from there.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
---
 drivers/pci/dwc/pci-dra7xx.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

Patch

diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c
index 009f6aeeee1c..4b02b2040eda 100644
--- a/drivers/pci/dwc/pci-dra7xx.c
+++ b/drivers/pci/dwc/pci-dra7xx.c
@@ -682,6 +682,11 @@  static int __init dra7xx_pcie_probe(struct platform_device *pdev)
 
 	switch (mode) {
 	case DW_PCIE_RC_TYPE:
+		if (!IS_ENABLED(CONFIG_PCI_DRA7XX_HOST)) {
+			ret = -ENODEV;
+			goto err_gpio;
+		}
+
 		dra7xx_pcie_writel(dra7xx, PCIECTRL_TI_CONF_DEVICE_TYPE,
 				   DEVICE_TYPE_RC);
 		ret = dra7xx_add_pcie_port(dra7xx, pdev);
@@ -689,6 +694,11 @@  static int __init dra7xx_pcie_probe(struct platform_device *pdev)
 			goto err_gpio;
 		break;
 	case DW_PCIE_EP_TYPE:
+		if (!IS_ENABLED(CONFIG_PCI_DRA7XX_EP)) {
+			ret = -ENODEV;
+			goto err_gpio;
+		}
+
 		dra7xx_pcie_writel(dra7xx, PCIECTRL_TI_CONF_DEVICE_TYPE,
 				   DEVICE_TYPE_EP);