Supply widgets are somewhat special and not all kinds of paths to or from supply widgets make sense. This patch adds a few sanity checks that errors out during the path instantiation for those invalid paths. This will prevent drivers to depend on weird behavior resulting from such paths as well as will allow the DAPM algorithms to assume that they never see such paths.
This patch adds checks for the following three invalid types of paths: * A path with a non-supply widget as a source connected to a supply widget as a sink. Such a path has no effect on either of the two connected widgets. * Paths with a connected() callback that have a non-supply widget as a sink. The DAPM algorithm only uses the conneceted() callback for supply widget power checks. And since it prevents caching of the DAPM state there is no intention to make it more generic as it has negative performance implications. * Paths which connect a supply to a mixer or mux via a control. Controls are only meant to affect the routing of audio data.
Signed-off-by: Lars-Peter Clausen lars@metafoo.de --- sound/soc/soc-dapm.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+)
diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c index 8792e47..38ab643 100644 --- a/sound/soc/soc-dapm.c +++ b/sound/soc/soc-dapm.c @@ -2198,6 +2198,27 @@ static int snd_soc_dapm_add_path(struct snd_soc_dapm_context *dapm, struct snd_soc_dapm_path *path; int ret;
+ if (wsink->is_supply && !wsource->is_supply) { + dev_err(dapm->dev, + "Connecting non-supply widget to supply widget is not supported (%s -> %s)\n", + wsource->name, wsink->name); + return -EINVAL; + } + + if (connected && !wsource->is_supply) { + dev_err(dapm->dev, + "connected() callback only supported for supply widgets (%s -> %s)\n", + wsource->name, wsink->name); + return -EINVAL; + } + + if (wsource->is_supply && control) { + dev_err(dapm->dev, + "Conditional paths are not supported for supply widgets (%s -> [%s] -> %s)\n", + wsource->name, control, wsink->name); + return -EINVAL; + } + path = kzalloc(sizeof(struct snd_soc_dapm_path), GFP_KERNEL); if (!path) return -ENOMEM;