list_for_each_entry((intel_encoder), &(dev)->mode_config.encoder_list, base.head) \
                if ((intel_encoder)->base.crtc == (__crtc))
 
+struct drm_i915_private;
+
 enum intel_dpll_id {
        DPLL_ID_PRIVATE = -1, /* non-shared dpll in use */
        /* real shared dpll ids must be >= 0 */
        const char *name;
        /* should match the index in the dev_priv->shared_dplls array */
        enum intel_dpll_id id;
+       void (*enable)(struct drm_i915_private *dev_priv,
+                      struct intel_shared_dpll *pll);
+       void (*disable)(struct drm_i915_private *dev_priv,
+                       struct intel_shared_dpll *pll);
 };
 
 /* Used by dp and fdi links */
 struct opregion_acpi;
 struct opregion_swsci;
 struct opregion_asle;
-struct drm_i915_private;
 
 struct intel_opregion {
        struct opregion_header __iomem *header;
 
 {
        struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
        struct intel_shared_dpll *pll = intel_crtc_to_shared_dpll(crtc);
-       int reg;
-       u32 val;
 
        /* PCH PLLs only available on ILK, SNB and IVB */
        BUG_ON(dev_priv->info->gen < 5);
                      pll->name, pll->active, pll->on,
                      crtc->base.base.id);
 
-       /* PCH refclock must be enabled first */
-       assert_pch_refclk_enabled(dev_priv);
-
        if (pll->active++) {
                WARN_ON(!pll->on);
                assert_shared_dpll_enabled(dev_priv, pll, NULL);
        WARN_ON(pll->on);
 
        DRM_DEBUG_KMS("enabling %s\n", pll->name);
-
-       reg = PCH_DPLL(pll->id);
-       val = I915_READ(reg);
-       val |= DPLL_VCO_ENABLE;
-       I915_WRITE(reg, val);
-       POSTING_READ(reg);
-       udelay(200);
-
+       pll->enable(dev_priv, pll);
        pll->on = true;
 }
 
 {
        struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
        struct intel_shared_dpll *pll = intel_crtc_to_shared_dpll(crtc);
-       int reg;
-       u32 val;
 
        /* PCH only available on ILK+ */
        BUG_ON(dev_priv->info->gen < 5);
                return;
 
        DRM_DEBUG_KMS("disabling %s\n", pll->name);
-
-       /* Make sure transcoder isn't still depending on us */
-       assert_pch_transcoder_disabled(dev_priv, crtc->pipe);
-
-       reg = PCH_DPLL(pll->id);
-       val = I915_READ(reg);
-       val &= ~DPLL_VCO_ENABLE;
-       I915_WRITE(reg, val);
-       POSTING_READ(reg);
-       udelay(200);
-
+       pll->disable(dev_priv, pll);
        pll->on = false;
 }
 
                intel_ddi_pll_init(dev);
 }
 
+static void ibx_pch_dpll_enable(struct drm_i915_private *dev_priv,
+                               struct intel_shared_dpll *pll)
+{
+       uint32_t reg, val;
+
+       /* PCH refclock must be enabled first */
+       assert_pch_refclk_enabled(dev_priv);
+
+       reg = PCH_DPLL(pll->id);
+       val = I915_READ(reg);
+       val |= DPLL_VCO_ENABLE;
+       I915_WRITE(reg, val);
+       POSTING_READ(reg);
+       udelay(200);
+}
+
+static void ibx_pch_dpll_disable(struct drm_i915_private *dev_priv,
+                                struct intel_shared_dpll *pll)
+{
+       struct drm_device *dev = dev_priv->dev;
+       struct intel_crtc *crtc;
+       uint32_t reg, val;
+
+       /* Make sure no transcoder isn't still depending on us. */
+       list_for_each_entry(crtc, &dev->mode_config.crtc_list, base.head) {
+               if (intel_crtc_to_shared_dpll(crtc) == pll)
+                       assert_pch_transcoder_disabled(dev_priv, crtc->pipe);
+       }
+
+       reg = PCH_DPLL(pll->id);
+       val = I915_READ(reg);
+       val &= ~DPLL_VCO_ENABLE;
+       I915_WRITE(reg, val);
+       POSTING_READ(reg);
+       udelay(200);
+}
+
 static char *ibx_pch_dpll_names[] = {
        "PCH DPLL A",
        "PCH DPLL B",
 
 static void ibx_pch_dpll_init(struct drm_device *dev)
 {
-       drm_i915_private_t *dev_priv = dev->dev_private;
+       struct drm_i915_private *dev_priv = dev->dev_private;
        int i;
 
        dev_priv->num_shared_dpll = 2;
        for (i = 0; i < dev_priv->num_shared_dpll; i++) {
                dev_priv->shared_dplls[i].id = i;
                dev_priv->shared_dplls[i].name = ibx_pch_dpll_names[i];
+               dev_priv->shared_dplls[i].enable = ibx_pch_dpll_enable;
+               dev_priv->shared_dplls[i].disable = ibx_pch_dpll_disable;
        }
 }
 
 static void intel_shared_dpll_init(struct drm_device *dev)
 {
-       drm_i915_private_t *dev_priv = dev->dev_private;
+       struct drm_i915_private *dev_priv = dev->dev_private;
 
        if (HAS_PCH_IBX(dev) || HAS_PCH_CPT(dev))
                ibx_pch_dpll_init(dev);