drm/armada: push responsibility for clock management to backend

Push responsibility for managing the clock during DPMS down into the
variant backend, rather than the CRTC layer having knowledge of its
state.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

drivers/gpu/drm/armada/armada_510.c

@@ -79,8 +79,27 @@ static int armada510_crtc_compute_clock(struct armada_crtc *dcrtc,
 	return 0;
 }
 
+static void armada510_crtc_disable(struct armada_crtc *dcrtc)
+{
+	if (!IS_ERR(dcrtc->clk)) {
+		clk_disable_unprepare(dcrtc->clk);
+		dcrtc->clk = ERR_PTR(-EINVAL);
+	}
+}
+
+static void armada510_crtc_enable(struct armada_crtc *dcrtc,
+	const struct drm_display_mode *mode)
+{
+	if (IS_ERR(dcrtc->clk)) {
+		dcrtc->clk = dcrtc->extclk[0];
+		WARN_ON(clk_prepare_enable(dcrtc->clk));
+	}
+}
+
 const struct armada_variant armada510_ops = {
 	.has_spu_adv_reg = true,
 	.init = armada510_crtc_init,
 	.compute_clock = armada510_crtc_compute_clock,
+	.disable = armada510_crtc_disable,
+	.enable = armada510_crtc_enable,
 };

drivers/gpu/drm/armada/armada_crtc.c

@@ -253,14 +253,14 @@ static void armada_drm_crtc_dpms(struct drm_crtc *crtc, int dpms)
 	if (dpms_blanked(dcrtc->dpms) != dpms_blanked(dpms)) {
 		if (dpms_blanked(dpms))
 			armada_drm_vblank_off(dcrtc);
-		else if (!IS_ERR(dcrtc->clk))
-			WARN_ON(clk_prepare_enable(dcrtc->clk));
+		else if (dcrtc->variant->enable)
+			dcrtc->variant->enable(dcrtc, &crtc->hwmode);
 		dcrtc->dpms = dpms;
 		armada_drm_crtc_update(dcrtc);
 		if (!dpms_blanked(dpms))
 			drm_crtc_vblank_on(&dcrtc->crtc);
-		else if (!IS_ERR(dcrtc->clk))
-			clk_disable_unprepare(dcrtc->clk);
+		else if (dcrtc->variant->disable)
+			dcrtc->variant->disable(dcrtc);
 	} else if (dcrtc->dpms != dpms) {
 		dcrtc->dpms = dpms;
 	}
@@ -462,13 +462,6 @@ static void armada_drm_crtc_mode_set_nofb(struct drm_crtc *crtc)
 		      adj->type, adj->flags);
 	DRM_DEBUG_KMS("lm %d rm %d tm %d bm %d\n", lm, rm, tm, bm);
 
-	/*
-	 * If we are blanked, we would have disabled the clock.  Re-enable
-	 * it so that compute_clock() does the right thing.
-	 */
-	if (!IS_ERR(dcrtc->clk) && dpms_blanked(dcrtc->dpms))
-		WARN_ON(clk_prepare_enable(dcrtc->clk));
-
 	/* Now compute the divider for real */
 	dcrtc->variant->compute_clock(dcrtc, adj, &sclk);
 
@@ -824,8 +817,8 @@ static void armada_drm_crtc_destroy(struct drm_crtc *crtc)
 	priv->dcrtc[dcrtc->num] = NULL;
 	drm_crtc_cleanup(&dcrtc->crtc);
 
-	if (!IS_ERR(dcrtc->clk))
-		clk_disable_unprepare(dcrtc->clk);
+	if (dcrtc->variant->disable)
+		dcrtc->variant->disable(dcrtc);
 
 	writel_relaxed(0, dcrtc->base + LCD_SPU_IRQ_ENA);
 

drivers/gpu/drm/armada/armada_drm.h

@@ -46,6 +46,8 @@ struct armada_variant {
 	int (*compute_clock)(struct armada_crtc *,
 			     const struct drm_display_mode *,
 			     uint32_t *);
+	void (*disable)(struct armada_crtc *);
+	void (*enable)(struct armada_crtc *, const struct drm_display_mode *);
 };
 
 /* Variant ops */