kernel: rework bcm47xx backport, fix build errors on the brcm47xx tar…

…get (#21974)

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/branches/chaos_calmer@48925 3c298f89-4303-0410-b956-a3cf2f4a3e73

target/linux/generic/files/include/linux/bcm47xx_nvram.h

@@ -0,0 +1,49 @@
+/*
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ */
+
+#ifndef __BCM47XX_NVRAM_H
+#define __BCM47XX_NVRAM_H
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/vmalloc.h>
+
+#if defined(CONFIG_BCM47XX_NVRAM) || defined(CONFIG_BCM47XX)
+int bcm47xx_nvram_init_from_mem(u32 base, u32 lim);
+int bcm47xx_nvram_getenv(const char *name, char *val, size_t val_len);
+int bcm47xx_nvram_gpio_pin(const char *name);
+char *bcm47xx_nvram_get_contents(size_t *val_len);
+static inline void bcm47xx_nvram_release_contents(char *nvram)
+{
+	vfree(nvram);
+};
+#else
+static inline int bcm47xx_nvram_init_from_mem(u32 base, u32 lim)
+{
+	return -ENOTSUPP;
+};
+static inline int bcm47xx_nvram_getenv(const char *name, char *val,
+				       size_t val_len)
+{
+	return -ENOTSUPP;
+};
+static inline int bcm47xx_nvram_gpio_pin(const char *name)
+{
+	return -ENOTSUPP;
+};
+
+static inline char *bcm47xx_nvram_get_contents(size_t *val_len)
+{
+	return NULL;
+};
+
+static inline void bcm47xx_nvram_release_contents(char *nvram)
+{
+};
+#endif
+
+#endif /* __BCM47XX_NVRAM_H */