| From foo@baz Sun Aug 26 09:13:00 CEST 2018 |
| From: Peter Senna Tschudin <peter.senna@gmail.com> |
| Date: Tue, 10 Jul 2018 16:01:45 +0200 |
| Subject: tools: usb: ffs-test: Fix build on big endian systems |
| |
| From: Peter Senna Tschudin <peter.senna@gmail.com> |
| |
| [ Upstream commit a2b22dddc7bb6110ac3b5ed1a60aa9279836fadb ] |
| |
| The tools/usb/ffs-test.c file defines cpu_to_le16/32 by using the C |
| library htole16/32 function calls. However, cpu_to_le16/32 are used when |
| initializing structures, i.e in a context where a function call is not |
| allowed. |
| |
| It works fine on little endian systems because htole16/32 are defined by |
| the C library as no-ops. But on big-endian systems, they are actually |
| doing something, which might involve calling a function, causing build |
| failures, such as: |
| |
| ffs-test.c:48:25: error: initializer element is not constant |
| #define cpu_to_le32(x) htole32(x) |
| ^~~~~~~ |
| ffs-test.c:128:12: note: in expansion of macro ‘cpu_to_le32’ |
| .magic = cpu_to_le32(FUNCTIONFS_DESCRIPTORS_MAGIC_V2), |
| ^~~~~~~~~~~ |
| |
| To solve this, we code cpu_to_le16/32 in a way that allows them to be |
| used when initializing structures. This fix was imported from |
| meta-openembedded/android-tools/fix-big-endian-build.patch written by |
| Thomas Petazzoni <thomas.petazzoni@free-electrons.com>. |
| |
| CC: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> |
| Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com> |
| Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> |
| Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| tools/usb/ffs-test.c | 19 ++++++++++++++++--- |
| 1 file changed, 16 insertions(+), 3 deletions(-) |
| |
| --- a/tools/usb/ffs-test.c |
| +++ b/tools/usb/ffs-test.c |
| @@ -44,12 +44,25 @@ |
| |
| /******************** Little Endian Handling ********************************/ |
| |
| -#define cpu_to_le16(x) htole16(x) |
| -#define cpu_to_le32(x) htole32(x) |
| +/* |
| + * cpu_to_le16/32 are used when initializing structures, a context where a |
| + * function call is not allowed. To solve this, we code cpu_to_le16/32 in a way |
| + * that allows them to be used when initializing structures. |
| + */ |
| + |
| +#if __BYTE_ORDER == __LITTLE_ENDIAN |
| +#define cpu_to_le16(x) (x) |
| +#define cpu_to_le32(x) (x) |
| +#else |
| +#define cpu_to_le16(x) ((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8)) |
| +#define cpu_to_le32(x) \ |
| + ((((x) & 0xff000000u) >> 24) | (((x) & 0x00ff0000u) >> 8) | \ |
| + (((x) & 0x0000ff00u) << 8) | (((x) & 0x000000ffu) << 24)) |
| +#endif |
| + |
| #define le32_to_cpu(x) le32toh(x) |
| #define le16_to_cpu(x) le16toh(x) |
| |
| - |
| /******************** Messages and Errors ***********************************/ |
| |
| static const char argv0[] = "ffs-test"; |