diff options
| -rw-r--r-- | drivers/firmware/meson/meson_sm.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/firmware/meson/meson_sm.c b/drivers/firmware/meson/meson_sm.c index 5f30a5774e57..ff204421117b 100644 --- a/drivers/firmware/meson/meson_sm.c +++ b/drivers/firmware/meson/meson_sm.c @@ -136,11 +136,14 @@ EXPORT_SYMBOL(meson_sm_call); * @arg4: SMC32 Argument 4 * * Return: size of read data on success, a negative value on error + * When 0 is returned there is no guarantee about the amount of + * data read and bsize bytes are copied in buffer. */ int meson_sm_call_read(void *buffer, unsigned int bsize, unsigned int cmd_index, u32 arg0, u32 arg1, u32 arg2, u32 arg3, u32 arg4) { u32 size; + int ret; if (!fw.chip) return -ENOENT; @@ -154,13 +157,18 @@ int meson_sm_call_read(void *buffer, unsigned int bsize, unsigned int cmd_index, if (meson_sm_call(cmd_index, &size, arg0, arg1, arg2, arg3, arg4) < 0) return -EINVAL; - if (!size || size > bsize) + if (size > bsize) return -EINVAL; + ret = size; + + if (!size) + size = bsize; + if (buffer) memcpy(buffer, fw.sm_shmem_out_base, size); - return size; + return ret; } EXPORT_SYMBOL(meson_sm_call_read); |