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author | Peter Senna Tschudin <peter.senna@gmail.com> | 2018-07-10 17:01:45 +0300 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-05 10:18:34 +0300 |
commit | 7b85bc4bea0f1c922315aaf9451c544b69dc20f6 (patch) | |
tree | b04eb9c1976310836dbf605c2b284820443bc929 /tools | |
parent | 5e02503f2a99621059daaf176e970b083648e0bb (diff) | |
download | linux-7b85bc4bea0f1c922315aaf9451c544b69dc20f6.tar.xz |
tools: usb: ffs-test: Fix build on big endian systems
[ 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>
Diffstat (limited to 'tools')
-rw-r--r-- | tools/usb/ffs-test.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/tools/usb/ffs-test.c b/tools/usb/ffs-test.c index 88d5e71be044..47dfa0b0fcd7 100644 --- 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"; |