Some systems use a special keyboard shortcut to mute speaker audio. On systems using CS35L41 HDA which have this shortcut, add a mechanism which uses ACPI notifications to determine when the shortcut is pressed, and then mute the amps inside the driver.
Since this is not a normal mute mechanism, it does not go through userspace. To allow userspace to be able to track this special state, add an ALSA control which tracks the state of this forced mute
Stefan Binding (1): ALSA: hda: cs35l41: Add read-only ALSA control for forced mute
Vitaly Rodionov (1): ALSA: hda: cs35l41: Support mute notifications for CS35L41 HDA
sound/pci/hda/cs35l41_hda.c | 132 ++++++++++++++++++++++++++++++---- sound/pci/hda/cs35l41_hda.h | 3 + sound/pci/hda/hda_component.h | 4 ++ sound/pci/hda/patch_realtek.c | 57 ++++++++++++++- 4 files changed, 182 insertions(+), 14 deletions(-)