MIPS: ath79: add a common PCI registration function

The current code unconditionally registers the AR724X
specific PCI controller, even if the kernel is running
on a different SoC.

Add a common function for PCI controller registration,
and only register the AR724X PCI controller if the kernel
is running on an AR724X SoC.
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3488/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/ath79/mach-ubnt-xm.c

@@ -111,6 +111,7 @@ static void __init ubnt_xm_init(void)
 	ath724x_pci_add_data(ubnt_xm_pci_data, ARRAY_SIZE(ubnt_xm_pci_data));
 #endif /* CONFIG_PCI */
 
+	ath79_register_pci();
 }
 
 MIPS_MACHINE(ATH79_MACH_UBNT_XM,

arch/mips/ath79/pci.c

@@ -9,6 +9,8 @@
  */
 
 #include <linux/pci.h>
+#include <asm/mach-ath79/ath79.h>
+#include <asm/mach-ath79/pci.h>
 #include "pci.h"
 
 static struct ath724x_pci_data *pci_data;
@@ -44,3 +46,11 @@ int pcibios_plat_dev_init(struct pci_dev *dev)
 
 	return PCIBIOS_SUCCESSFUL;
 }
+
+int __init ath79_register_pci(void)
+{
+	if (soc_is_ar724x())
+		return ath724x_pcibios_init();
+
+	return -ENODEV;
+}

arch/mips/ath79/pci.h

@@ -18,4 +18,10 @@ struct ath724x_pci_data {
 
 void ath724x_pci_add_data(struct ath724x_pci_data *data, int size);
 
+#ifdef CONFIG_PCI
+int ath79_register_pci(void);
+#else
+static inline int ath79_register_pci(void) { return 0; }
+#endif
+
 #endif /* __ASM_MACH_ATH79_PCI_ATH724X_H */

arch/mips/pci/pci-ath724x.c

@@ -137,5 +137,3 @@ int __init ath724x_pcibios_init(void)
 
 	return PCIBIOS_SUCCESSFUL;
 }
-
-arch_initcall(ath724x_pcibios_init);