Merge tag 'mute-led-rework' of https://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound into asoc-5.13

ALSA: control - add generic LED API

This patchset tries to resolve the diversity in the audio LED
control among the ALSA drivers. A new control layer registration
is introduced which allows to run additional operations on
top of the elementary ALSA sound controls.

A new control access group (three bits in the access flags)
was introduced to carry the LED group information for
the sound controls. The low-level sound drivers can just
mark those controls using this access group. This information
is not exported to the user space, but user space can
manage the LED sound control associations through sysfs
(last patch) per Mark's request. It makes things fully
configurable in the kernel and user space (UCM).

The actual state ('route') evaluation is really easy
(the minimal value check for all channels / controls / cards).
If there's more complicated logic for a given hardware,
the card driver may eventually export a new read-only
sound control for the LED group and do the logic itself.

The new LED trigger control code is completely separated
and possibly optional (there's no symbol dependency).
The full code separation allows eventually to move this
LED trigger control to the user space in future.
Actually it replaces the already present functionality
in the kernel space (HDA drivers) and allows a quick adoption
for the recent hardware (ASoC codecs including SoundWire).

snd_ctl_led            24576  0

The sound driver implementation is really easy:

1) call snd_ctl_led_request() when control LED layer should be
   automatically activated
   / it calls module_request("snd-ctl-led") on demand /
2) mark all related kcontrols with
        SNDRV_CTL_ELEM_ACCESS_SPK_LED or
        SNDRV_CTL_ELEM_ACCESS_MIC_LED

Link: https://lore.kernel.org/r/20210317172945.842280-1-perex@perex.cz
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 14 insertions, 11 deletions

diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 2eeaa42f2e08..9d4b0e9b1aa1 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -230,8 +230,8 @@ int dsa_port_hsr_join(struct dsa_port *dp, struct net_device *hsr);
 void dsa_port_hsr_leave(struct dsa_port *dp, struct net_device *hsr);
 extern const struct phylink_mac_ops dsa_port_phylink_mac_ops;
 
-static inline bool dsa_port_offloads_netdev(struct dsa_port *dp,
-					    struct net_device *dev)
+static inline bool dsa_port_offloads_bridge_port(struct dsa_port *dp,
+						 struct net_device *dev)
 {
 	/* Switchdev offloading can be configured on: */
 
@@ -241,12 +241,6 @@ static inline bool dsa_port_offloads_netdev(struct dsa_port *dp,
 		 */
 		return true;
 
-	if (dp->bridge_dev == dev)
-		/* DSA ports connected to a bridge, and event was emitted
-		 * for the bridge.
-		 */
-		return true;
-
 	if (dp->lag_dev == dev)
 		/* DSA ports connected to a bridge via a LAG */
 		return true;
@@ -254,14 +248,23 @@ static inline bool dsa_port_offloads_netdev(struct dsa_port *dp,
 	return false;
 }
 
+static inline bool dsa_port_offloads_bridge(struct dsa_port *dp,
+					    struct net_device *bridge_dev)
+{
+	/* DSA ports connected to a bridge, and event was emitted
+	 * for the bridge.
+	 */
+	return dp->bridge_dev == bridge_dev;
+}
+
 /* Returns true if any port of this tree offloads the given net_device */
-static inline bool dsa_tree_offloads_netdev(struct dsa_switch_tree *dst,
-					    struct net_device *dev)
+static inline bool dsa_tree_offloads_bridge_port(struct dsa_switch_tree *dst,
+						 struct net_device *dev)
 {
 	struct dsa_port *dp;
 
 	list_for_each_entry(dp, &dst->ports, list)
-		if (dsa_port_offloads_netdev(dp, dev))
+		if (dsa_port_offloads_bridge_port(dp, dev))
 			return true;
 
 	return false;