gpu: ipu-v3: remove IRQ dance on DC channel disable

This has never worked properly, as the IRQ got retriggered immediately
on unmask. Remove the IRQ wait dance, as it is apparently safe to disable
the DC channel at any point in time.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

drivers/gpu/ipu-v3/ipu-dc.c

@@ -112,8 +112,6 @@ struct ipu_dc_priv {
 	struct ipu_dc		channels[IPU_DC_NUM_CHANNELS];
 	struct mutex		mutex;
 	struct completion	comp;
-	int			dc_irq;
-	int			dp_irq;
 	int			use_count;
 };
 
@@ -262,47 +260,13 @@ void ipu_dc_enable_channel(struct ipu_dc *dc)
 }
 EXPORT_SYMBOL_GPL(ipu_dc_enable_channel);
 
-static irqreturn_t dc_irq_handler(int irq, void *dev_id)
-{
-	struct ipu_dc *dc = dev_id;
-	u32 reg;
-
-	reg = readl(dc->base + DC_WR_CH_CONF);
-	reg &= ~DC_WR_CH_CONF_PROG_TYPE_MASK;
-	writel(reg, dc->base + DC_WR_CH_CONF);
-
-	/* The Freescale BSP kernel clears DIx_COUNTER_RELEASE here */
-
-	complete(&dc->priv->comp);
-	return IRQ_HANDLED;
-}
-
 void ipu_dc_disable_channel(struct ipu_dc *dc)
 {
-	struct ipu_dc_priv *priv = dc->priv;
-	int irq;
-	unsigned long ret;
 	u32 val;
 
-	/* TODO: Handle MEM_FG_SYNC differently from MEM_BG_SYNC */
-	if (dc->chno == 1)
-		irq = priv->dc_irq;
-	else if (dc->chno == 5)
-		irq = priv->dp_irq;
-	else
-		return;
-
-	init_completion(&priv->comp);
-	enable_irq(irq);
-	ret = wait_for_completion_timeout(&priv->comp, msecs_to_jiffies(50));
-	disable_irq(irq);
-	if (ret == 0) {
-		dev_warn(priv->dev, "DC stop timeout after 50 ms\n");
-
-		val = readl(dc->base + DC_WR_CH_CONF);
-		val &= ~DC_WR_CH_CONF_PROG_TYPE_MASK;
-		writel(val, dc->base + DC_WR_CH_CONF);
-	}
+	val = readl(dc->base + DC_WR_CH_CONF);
+	val &= ~DC_WR_CH_CONF_PROG_TYPE_MASK;
+	writel(val, dc->base + DC_WR_CH_CONF);
 }
 EXPORT_SYMBOL_GPL(ipu_dc_disable_channel);
 
@@ -389,7 +353,7 @@ int ipu_dc_init(struct ipu_soc *ipu, struct device *dev,
 	struct ipu_dc_priv *priv;
 	static int channel_offsets[] = { 0, 0x1c, 0x38, 0x54, 0x58, 0x5c,
 		0x78, 0, 0x94, 0xb4};
-	int i, ret;
+	int i;
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
@@ -410,23 +374,6 @@ int ipu_dc_init(struct ipu_soc *ipu, struct device *dev,
 		priv->channels[i].base = priv->dc_reg + channel_offsets[i];
 	}
 
-	priv->dc_irq = ipu_map_irq(ipu, IPU_IRQ_DC_FC_1);
-	if (!priv->dc_irq)
-		return -EINVAL;
-	ret = devm_request_irq(dev, priv->dc_irq, dc_irq_handler, 0, NULL,
-			       &priv->channels[1]);
-	if (ret < 0)
-		return ret;
-	disable_irq(priv->dc_irq);
-	priv->dp_irq = ipu_map_irq(ipu, IPU_IRQ_DP_SF_END);
-	if (!priv->dp_irq)
-		return -EINVAL;
-	ret = devm_request_irq(dev, priv->dp_irq, dc_irq_handler, 0, NULL,
-			       &priv->channels[5]);
-	if (ret < 0)
-		return ret;
-	disable_irq(priv->dp_irq);
-
 	writel(DC_WR_CH_CONF_WORD_SIZE_24 | DC_WR_CH_CONF_DISP_ID_PARALLEL(1) |
 			DC_WR_CH_CONF_PROG_DI_ID,
 			priv->channels[1].base + DC_WR_CH_CONF);