The recent bug report suggests that BCLK setup for i915 HSW/BDW needs
to be updated at each HDMI hotplug, not only at initialization and
resume. That is, we need to update HSW_EM4 and HSW_EM5 registers at
ELD notification, too. Otherwise the HDMI audio may be out of sync
and played in a wrong pitch.
However, the HDA codec driver has no access to the controller
registers, and currently the code managing these registers is in
hda_intel.c, i.e. local to the controller driver. For allowing the
explicit BCLK update from the codec driver, as in this patch, the
former haswell_set_bclk() in hda_intel.c is moved to hdac_i915.c and
exposed as snd_hdac_i915_set_bclk(). This is called from both the HDA
controller driver and intel_pin_eld_notify() in HDMI codec driver.
Along with this change, snd_hdac_get_display_clk() gets dropped as
it's no longer used.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91410
Cc: <stable@vger.kernel.org> # v4.5+
Signed-off-by: Takashi Iwai <tiwai@suse.de>