From: Libin Yang <libin.yang@xxxxxxxxx> This issue is caused by: 6014ac12: drm/i915/audio: set proper N/M in modeset Some special monitors will have noise or even no sound after applying the patch 6014ac12. In patch 6014ac12, it will reset the cts value to 0 for HDMI. However, we need disable Enable CTS or M Prog bit. This is the initial setting after HW reset. Signed-off-by: Libin Yang <libin.yang@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_audio.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_audio.c b/drivers/gpu/drm/i915/intel_audio.c index 813fd74..a472d35 100644 --- a/drivers/gpu/drm/i915/intel_audio.c +++ b/drivers/gpu/drm/i915/intel_audio.c @@ -332,6 +332,13 @@ hsw_hdmi_audio_config_update(struct intel_crtc *intel_crtc, enum port port, int n; u32 tmp; + /* reset CTS value to 0 */ + tmp = I915_READ(HSW_AUD_M_CTS_ENABLE(pipe)); + tmp &= ~AUD_CONFIG_M_MASK; + tmp &= ~AUD_M_CTS_M_VALUE_INDEX; + tmp |= AUD_M_CTS_M_PROG_ENABLE; + I915_WRITE(HSW_AUD_M_CTS_ENABLE(pipe), tmp); + tmp = I915_READ(HSW_AUD_CFG(pipe)); tmp &= ~AUD_CONFIG_N_VALUE_INDEX; tmp &= ~AUD_CONFIG_PIXEL_CLOCK_HDMI_MASK; @@ -351,10 +358,12 @@ hsw_hdmi_audio_config_update(struct intel_crtc *intel_crtc, enum port port, I915_WRITE(HSW_AUD_CFG(pipe), tmp); + /* + * Let's disable "Enable CTS or M Prog bit" + * and let HW calculate the value + */ tmp = I915_READ(HSW_AUD_M_CTS_ENABLE(pipe)); - tmp &= ~AUD_CONFIG_M_MASK; - tmp &= ~AUD_M_CTS_M_VALUE_INDEX; - tmp |= AUD_M_CTS_M_PROG_ENABLE; + tmp &= ~AUD_M_CTS_M_PROG_ENABLE; I915_WRITE(HSW_AUD_M_CTS_ENABLE(pipe), tmp); } -- 2.7.4 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
