ASoC: Simplify format_register_str() without stack usages

Instead of allocating two string buffers on stack and copying them
back, manipulate directly the target string buffer.  This simplifies
the code well.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Takashi Iwai 2015-05-26 14:40:14 +02:00 committed by Mark Brown
parent 9e4980896c
commit d6b6c2ca6a
1 changed files with 9 additions and 18 deletions

View File

@ -92,30 +92,21 @@ static int format_register_str(struct snd_soc_codec *codec,
int wordsize = min_bytes_needed(codec->driver->reg_cache_size) * 2;
int regsize = codec->driver->reg_word_size * 2;
int ret;
char tmpbuf[len + 1];
char regbuf[regsize + 1];
/* since tmpbuf is allocated on the stack, warn the callers if they
* try to abuse this function */
WARN_ON(len > 63);
/* +2 for ': ' and + 1 for '\n' */
if (wordsize + regsize + 2 + 1 != len)
return -EINVAL;
sprintf(buf, "%.*x: ", wordsize, reg);
buf += wordsize + 2;
ret = snd_soc_read(codec, reg);
if (ret < 0) {
memset(regbuf, 'X', regsize);
regbuf[regsize] = '\0';
} else {
snprintf(regbuf, regsize + 1, "%.*x", regsize, ret);
}
/* prepare the buffer */
snprintf(tmpbuf, len + 1, "%.*x: %s\n", wordsize, reg, regbuf);
/* copy it back to the caller without the '\0' */
memcpy(buf, tmpbuf, len);
if (ret < 0)
memset(buf, 'X', regsize);
else
sprintf(buf, "%.*x", regsize, ret);
buf[regsize] = '\n';
/* no NUL-termination needed */
return 0;
}