diff options
author | Jani Nikula <jani.nikula@intel.com> | 2014-07-04 10:00:37 +0800 |
---|---|---|
committer | Takashi Iwai <tiwai@suse.de> | 2014-07-04 07:46:09 +0200 |
commit | c149dcb5c60bfea8871f16dfcc0690255eeb825f (patch) | |
tree | f117d9197504d5b02fa0d66d685c556ed30b5489 /drivers | |
parent | a12137e779e17413f87026202a890f8143858259 (diff) | |
download | linux-c149dcb5c60bfea8871f16dfcc0690255eeb825f.tar.bz2 |
drm/i915: provide interface for audio driver to query cdclk
For Haswell and Broadwell, if the display power well has been disabled,
the display audio controller divider values EM4 M VALUE and EM5 N VALUE
will have been lost. The CDCLK frequency is required for reprogramming them
to generate 24MHz HD-A link BCLK. So provide a private interface for the
audio driver to query CDCLK.
This is a stopgap solution until a more generic interface between audio
and display drivers has been implemented.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Mengdong Lin <mengdong.lin@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/gpu/drm/i915/intel_pm.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 6463f0201cf2..409d62676854 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -6053,6 +6053,27 @@ int i915_release_power_well(void) } EXPORT_SYMBOL_GPL(i915_release_power_well); +/* + * Private interface for the audio driver to get CDCLK in kHz. + * + * Caller must request power well using i915_request_power_well() prior to + * making the call. + */ +int i915_get_cdclk_freq(void) +{ + struct drm_i915_private *dev_priv; + + if (!hsw_pwr) + return -ENODEV; + + dev_priv = container_of(hsw_pwr, struct drm_i915_private, + power_domains); + + return intel_ddi_get_cdclk_freq(dev_priv); +} +EXPORT_SYMBOL_GPL(i915_get_cdclk_freq); + + #define POWER_DOMAIN_MASK (BIT(POWER_DOMAIN_NUM) - 1) #define HSW_ALWAYS_ON_POWER_DOMAINS ( \ |