[Intel-gfx] [PATCH] drm/i915/cnl: Enable Audio Pin Buffer.

[Rodrigo Vivi]

Starting on CNL, we need to enable Audio Pin Buffer.

By the spec it seems that this is part of audio programming,
so let's give them the hability to set/unset this as needed.

v2: With a hook so audio driver can control it.
v3: Put back reg definition lost on v2.

Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
Cc: Jani Nikula <jani.nikula at intel.com>
Cc: Sanyog Kale <sanyog.r.kale at intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h    |  3 +++
 drivers/gpu/drm/i915/intel_audio.c | 16 ++++++++++++++++
 include/drm/i915_component.h       |  6 ++++++
 3 files changed, 25 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 64cc674..aab38da 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2643,6 +2643,9 @@ enum skl_disp_power_wells {
 #define I915_HDMI_LPE_AUDIO_BASE	(VLV_DISPLAY_BASE + 0x65000)
 #define I915_HDMI_LPE_AUDIO_SIZE	0x1000
 
+#define AUDIO_PIN_BUF_CTL		_MMIO(0x48414)
+#define AUDIO_PIN_BUF_ENABLE		(1 << 31)
+
 /* DisplayPort Audio w/ LPE */
 #define VLV_AUD_CHICKEN_BIT_REG		_MMIO(VLV_DISPLAY_BASE + 0x62F38)
 #define VLV_CHICKEN_BIT_DBG_ENABLE	(1 << 0)
diff --git a/drivers/gpu/drm/i915/intel_audio.c b/drivers/gpu/drm/i915/intel_audio.c
index d805b6e..0c83254 100644
--- a/drivers/gpu/drm/i915/intel_audio.c
+++ b/drivers/gpu/drm/i915/intel_audio.c
@@ -865,6 +865,21 @@ static int i915_audio_component_get_eld(struct device *kdev, int port,
 	return ret;
 }
 
+static void i915_audio_component_pin_buf(struct device *kdev, bool enable)
+{
+	struct drm_i915_private *dev_priv = kdev_to_i915(kdev);
+
+	if (!IS_CANNONLAKE(dev_priv))
+		return;
+
+	if (enable)
+		I915_WRITE(AUDIO_PIN_BUF_CTL, I915_READ(AUDIO_PIN_BUF_CTL) |
+			   AUDIO_PIN_BUF_ENABLE);
+	else
+		I915_WRITE(AUDIO_PIN_BUF_CTL, I915_READ(AUDIO_PIN_BUF_CTL) &
+			   ~AUDIO_PIN_BUF_ENABLE);
+}
+
 static const struct i915_audio_component_ops i915_audio_component_ops = {
 	.owner		= THIS_MODULE,
 	.get_power	= i915_audio_component_get_power,
@@ -873,6 +888,7 @@ static int i915_audio_component_get_eld(struct device *kdev, int port,
 	.get_cdclk_freq	= i915_audio_component_get_cdclk_freq,
 	.sync_audio_rate = i915_audio_component_sync_audio_rate,
 	.get_eld	= i915_audio_component_get_eld,
+	.pin_buf	= i915_audio_component_pin_buf,
 };
 
 static int i915_audio_component_bind(struct device *i915_kdev,
diff --git a/include/drm/i915_component.h b/include/drm/i915_component.h
index 545c6e0..b8875d4 100644
--- a/include/drm/i915_component.h
+++ b/include/drm/i915_component.h
@@ -79,6 +79,12 @@ struct i915_audio_component_ops {
 	 */
 	int (*get_eld)(struct device *, int port, int pipe, bool *enabled,
 		       unsigned char *buf, int max_bytes);
+	/**
+	 * @pin_buf: Enable or disable pin buffer.
+	 *
+	 * Allow audio driver the toggle pin buffer.
+	 */
+	void (*pin_buf)(struct device *, bool enable);
 };
 
 /**
-- 
1.9.1