introduce strerrorp

putting an error pointer into strerror can be a bit confusing since
strerror takes a positive error code but PTR_ERR returns a negative
number, so we have to do strerror(-PTR_ERR(errp)). Some places got
this wrong already, so introduce a strerrorp function which directly
takes an error pointer.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/errno.h b/include/errno.h
index 025816e067..496ccab0ee 100644
--- a/include/errno.h
+++ b/include/errno.h
@@ -2,6 +2,7 @@
 #define __ERRNO_H
 
 #include <asm-generic/errno.h>
+#include <linux/err.h>
 
 extern int errno;
 
@@ -9,4 +10,9 @@ void perror(const char *s);
 const char *errno_str(void);
 const char *strerror(int errnum);
 
+static inline const char *strerrorp(const void *errp)
+{
+	return strerror(-PTR_ERR(errp));
+}
+
 #endif /* __ERRNO_H */