For best power-saving we want to sleep on poll() for as long as possible, we don't want to wake unnecessarily for arbitrary time limits. Adds function compress_set_max_poll_wait() so that client can configure the poll() timeout.
--- compress.c | 17 ++++++++++++++--- include/tinycompress/tinycompress.h | 10 ++++++++++ 2 files changed, 24 insertions(+), 3 deletions(-)
diff --git a/compress.c b/compress.c index 801f055..478652a 100644 --- a/compress.c +++ b/compress.c @@ -77,12 +77,16 @@
#define COMPR_ERR_MAX 128
+/* Default maximum time we will wait in a poll() - 20 seconds */ +#define DEFAULT_MAX_POLL_WAIT_MS 20000 + struct compress { int fd; unsigned int flags; char error[COMPR_ERR_MAX]; struct compr_config *config; int running; + int max_poll_wait_ms; };
static int oops(struct compress *compress, int e, const char *fmt, ...) @@ -217,6 +221,8 @@ struct compress *compress_open(unsigned int card, unsigned int device,
snprintf(fn, sizeof(fn), "/dev/snd/comprC%uD%u", card, device);
+ compress->max_poll_wait_ms = DEFAULT_MAX_POLL_WAIT_MS; + compress->flags = flags; if (!((flags & COMPRESS_OUT) || (flags & COMPRESS_IN))) { oops(&bad_compress, -EINVAL, "can't deduce device direction from given flags"); @@ -331,9 +337,9 @@ int compress_write(struct compress *compress, const void *buf, unsigned int size return oops(compress, errno, "cannot get avail");
/* we will write only when avail > fragment size */ - if (avail.avail < compress->config->fragment_size) { - /* nothing to write so wait for 10secs */ - ret = poll(&fds, 1, 1000000); + if (avail.avail < compress->config.fragment_size) { + /* nothing to write so wait */ + ret = poll(&fds, 1, compress->max_poll_wait_ms); if (ret < 0) return oops(compress, errno, "poll error"); if (ret == 0) @@ -441,3 +447,8 @@ bool is_codec_supported(unsigned int card, unsigned int device, return ret; }
+void compress_set_max_poll_wait(struct compress *compress, int milliseconds) +{ + compress->max_poll_wait_ms = milliseconds; +} + diff --git a/include/tinycompress/tinycompress.h b/include/tinycompress/tinycompress.h index 49c0ff2..982ff6b 100644 --- a/include/tinycompress/tinycompress.h +++ b/include/tinycompress/tinycompress.h @@ -190,6 +190,16 @@ int compress_drain(struct compress *compress); bool is_codec_supported(unsigned int card, unsigned int device, unsigned int flags, struct snd_codec *codec);
+/* + * compress_set_max_poll_wait: set the maximum time tinycompress + * will wait for driver to signal a poll(). Interval is in + * milliseconds. + * Pass interval of -1 to disable timeout and make poll() wait + * until driver signals. + * If this function is not used the timeout defaults to 20 seconds. + */ +void compress_set_max_poll_wait(struct compress *compress, int milliseconds); + int is_compress_running(struct compress *compress);
int is_compress_ready(struct compress *compress);