From: Wang Xingchao Date: Thu, 30 May 2013 14:07:10 +0000 (+0800) Subject: ALSA: hda - Add power-welll support for haswell HDA X-Git-Tag: v3.11-rc1~65^2~61^2~55 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=99a2008d0b32d72dfc2a54e7be1eb698dd2e3bd6;p=pandora-kernel.git ALSA: hda - Add power-welll support for haswell HDA For Intel Haswell chip, HDA controller and codec have power well dependency from GPU side. This patch added support to request/release power well in audio driver. Power save feature should be enabled to get runtime power saving. There's deadlock when request_module(i915) in azx_probe. It looks like: device_lock(audio pci device) -> azx_probe -> module_request (or symbol_request) -> modprobe (userspace) -> i915 init -> drm_pci_init -> pci_register_driver -> bus_add_driver -> driver_attach -> which in turn tries all locks on pci bus, and when it tries the one on the audio device, it will deadlock. This patch introduce a work to store remaining probe stuff, and let request_module run in safe work context. Signed-off-by: Wang Xingchao Reviewed-by: Takashi Iwai Reviewed-by: Liam Girdwood Reviewed-by: David Henningsson Signed-off-by: Daniel Vetter --- Reading git-diff-tree failed