Merge tag 'tags/mute-led-rework' into for-next

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, 8 insertions, 4 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 521d36bb0803..034af85f79d8 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -70,7 +70,7 @@ __cfg80211_wdev_from_attrs(struct cfg80211_registered_device *rdev,
 	struct wireless_dev *result = NULL;
 	bool have_ifidx = attrs[NL80211_ATTR_IFINDEX];
 	bool have_wdev_id = attrs[NL80211_ATTR_WDEV];
-	u64 wdev_id;
+	u64 wdev_id = 0;
 	int wiphy_idx = -1;
 	int ifidx = -1;
 
@@ -14789,6 +14789,7 @@ bad_tid_conf:
 #define NL80211_FLAG_NEED_WDEV_UP	(NL80211_FLAG_NEED_WDEV |\
 					 NL80211_FLAG_CHECK_NETDEV_UP)
 #define NL80211_FLAG_CLEAR_SKB		0x20
+#define NL80211_FLAG_NO_WIPHY_MTX	0x40
 
 static int nl80211_pre_doit(const struct genl_ops *ops, struct sk_buff *skb,
 			    struct genl_info *info)
@@ -14840,7 +14841,7 @@ static int nl80211_pre_doit(const struct genl_ops *ops, struct sk_buff *skb,
 		info->user_ptr[0] = rdev;
 	}
 
-	if (rdev) {
+	if (rdev && !(ops->internal_flags & NL80211_FLAG_NO_WIPHY_MTX)) {
 		wiphy_lock(&rdev->wiphy);
 		/* we keep the mutex locked until post_doit */
 		__release(&rdev->wiphy.mtx);
@@ -14865,7 +14866,8 @@ static void nl80211_post_doit(const struct genl_ops *ops, struct sk_buff *skb,
 		}
 	}
 
-	if (info->user_ptr[0]) {
+	if (info->user_ptr[0] &&
+	    !(ops->internal_flags & NL80211_FLAG_NO_WIPHY_MTX)) {
 		struct cfg80211_registered_device *rdev = info->user_ptr[0];
 
 		/* we kept the mutex locked since pre_doit */
@@ -15329,7 +15331,9 @@ static const struct genl_small_ops nl80211_small_ops[] = {
 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 		.doit = nl80211_wiphy_netns,
 		.flags = GENL_UNS_ADMIN_PERM,
-		.internal_flags = NL80211_FLAG_NEED_WIPHY,
+		.internal_flags = NL80211_FLAG_NEED_WIPHY |
+				  NL80211_FLAG_NEED_RTNL |
+				  NL80211_FLAG_NO_WIPHY_MTX,
 	},
 	{
 		.cmd = NL80211_CMD_GET_SURVEY,