diff options
| author | Brian Swetland <swetland@google.com> | 2009-12-07 15:28:08 -0800 |
|---|---|---|
| committer | Daniel Walker <dwalker@codeaurora.org> | 2010-05-12 09:15:31 -0700 |
| commit | 636eb9cbaef7989ce7809a0d842bf78470a0a1f4 (patch) | |
| tree | 1a12088ad69cb37d5e3f3f25bdf03c7c9e8a7846 /arch | |
| parent | 1207babdcdfe5501d1528c86b445a9d1045ecc01 (diff) | |
| download | linux-636eb9cbaef7989ce7809a0d842bf78470a0a1f4.tar.bz2 | |
msm: smd: provide atomic channel writes
Some smd clients may write from multiple threads, in which case it's
not safe to call smd_write without holding a lock. smd_write_atomic()
provides the same functionality as smd_write() but obtains the smd
lock first.
Signed-off-by: Brian Swetland <swetland@google.com>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/mach-msm/include/mach/msm_smd.h | 1 | ||||
| -rw-r--r-- | arch/arm/mach-msm/smd.c | 10 |
2 files changed, 11 insertions, 0 deletions
diff --git a/arch/arm/mach-msm/include/mach/msm_smd.h b/arch/arm/mach-msm/include/mach/msm_smd.h index bdf7731ab680..aa076e466e4c 100644 --- a/arch/arm/mach-msm/include/mach/msm_smd.h +++ b/arch/arm/mach-msm/include/mach/msm_smd.h @@ -38,6 +38,7 @@ int smd_read(smd_channel_t *ch, void *data, int len); ** it will return the requested length written or an error. */ int smd_write(smd_channel_t *ch, const void *data, int len); +int smd_write_atomic(smd_channel_t *ch, const void *data, int len); int smd_write_avail(smd_channel_t *ch); int smd_read_avail(smd_channel_t *ch); diff --git a/arch/arm/mach-msm/smd.c b/arch/arm/mach-msm/smd.c index 655fe42506ca..086fd77dc891 100644 --- a/arch/arm/mach-msm/smd.c +++ b/arch/arm/mach-msm/smd.c @@ -804,6 +804,16 @@ int smd_write(smd_channel_t *ch, const void *data, int len) return ch->write(ch, data, len); } +int smd_write_atomic(smd_channel_t *ch, const void *data, int len) +{ + unsigned long flags; + int res; + spin_lock_irqsave(&smd_lock, flags); + res = ch->write(ch, data, len); + spin_unlock_irqrestore(&smd_lock, flags); + return res; +} + int smd_read_avail(smd_channel_t *ch) { return ch->read_avail(ch); |