[PATCH v2] staging: rtl8723bs: remove unused BIT macros definitions

Fabio Aiuto
2021-07-30T13:40:55Z

BIT(x) macro used all over the driver is defined in
include/vsdo/bit.h as

- #define BIT(nr) (UL(1) << (nr))

which is safer than the local BIT macros declared.
Local macros shift a signed integer which brings
unespected results. For example:

(unsigned long)(1 << 31) => 0xffffffff80000000

shift.c:

int main() {
printf("%lx\n", (unsigned long)(1 << 31));
printf("%lx\n", (unsigned long)(1U << 31));
return 0;
}

...

$ ./shift
ffffffff80000000
80000000

...

So just remove redundant, less safe macro declarations.

Suggested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Fabio Aiuto <fabioaiuto83@gmail.com>
---
Changes in v2:
- edited changelog

drivers/staging/rtl8723bs/include/osdep_service.h | 4 ----
drivers/staging/rtl8723bs/include/wifi.h | 8 --------
2 files changed, 12 deletions(-)

diff --git a/drivers/staging/rtl8723bs/include/osdep_service.h b/drivers/staging/rtl8723bs/include/osdep_service.h
index b49838c7e457..bde415db4114 100644
--- a/drivers/staging/rtl8723bs/include/osdep_service.h
+++ b/drivers/staging/rtl8723bs/include/osdep_service.h
@@ -14,10 +14,6 @@

#include <osdep_service_linux.h>

-#ifndef BIT
- #define BIT(x) (1 << (x))
-#endif
-
#define BIT0 0x00000001
#define BIT1 0x00000002
#define BIT2 0x00000004
diff --git a/drivers/staging/rtl8723bs/include/wifi.h b/drivers/staging/rtl8723bs/include/wifi.h
index 0bd7b662b972..f03e26818d45 100644
--- a/drivers/staging/rtl8723bs/include/wifi.h
+++ b/drivers/staging/rtl8723bs/include/wifi.h
@@ -7,14 +7,6 @@
#ifndef _WIFI_H_
#define _WIFI_H_

-
-#ifdef BIT
-/* error "BIT define occurred earlier elsewhere!\n" */
-#undef BIT
-#endif
-#define BIT(x) (1 << (x))
-
-
#define WLAN_ETHHDR_LEN 14
#define WLAN_ETHADDR_LEN 6
#define WLAN_IEEE_OUI_LEN 3
--
2.20.1