ALSA: hda - restore BCLK M/N value as per CDCLK for HSW/BDW display HDA controller

For HSW/BDW display HD-A controller, hda_set_bclk() is defined to set BCLK
by programming the M/N values as per the core display clock (CDCLK) queried from
i915 display driver.

And the audio driver will also set BCLK in azx_first_init() since the display
driver can turn off the shared power in boot phase if only eDP is connected
and M/N values will be lost and must be reprogrammed.

Signed-off-by: Mengdong Lin <mengdong.lin@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 2 insertions, 0 deletions

diff --git a/sound/pci/hda/hda_i915.h b/sound/pci/hda/hda_i915.h
index bfd835f8f1aa..e6072c627583 100644
--- a/sound/pci/hda/hda_i915.h
+++ b/sound/pci/hda/hda_i915.h
@@ -18,10 +18,12 @@
 
 #ifdef CONFIG_SND_HDA_I915
 int hda_display_power(bool enable);
+void haswell_set_bclk(struct azx *chip);
 int hda_i915_init(void);
 int hda_i915_exit(void);
 #else
 static inline int hda_display_power(bool enable) { return 0; }
+static inline void haswell_set_bclk(struct azx *chip) { return; }
 static inline int hda_i915_init(void)
 {
         return -ENODEV;