drm: bridge: it66121: Don't use DDC error IRQs

The DDC error IRQs will fire on the IT6610 every time the FIFO is empty,
which is not very helpful. To resolve this, we can simply disable them,
and handle DDC errors in it66121_wait_ddc_ready().
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221214125821.12489-7-paul@crapouillou.net

drivers/gpu/drm/bridge/ite-it66121.c

@@ -515,16 +515,6 @@ static int it66121_get_edid_block(void *context, u8 *buf,
 	offset = (block % 2) * len;
 	block = block / 2;
 
-	ret = regmap_read(ctx->regmap, IT66121_INT_STATUS1_REG, &val);
-	if (ret)
-		return ret;
-
-	if (val & IT66121_INT_STATUS1_DDC_BUSHANG) {
-		ret = it66121_abort_ddc_ops(ctx);
-		if (ret)
-			return ret;
-	}
-
 	ret = it66121_clear_ddc_fifo(ctx);
 	if (ret)
 		return ret;
@@ -545,16 +535,6 @@ static int it66121_get_edid_block(void *context, u8 *buf,
 		if (ret)
 			return ret;
 
-		ret = regmap_read(ctx->regmap, IT66121_INT_STATUS1_REG, &val);
-		if (ret)
-			return ret;
-
-		if (val & IT66121_INT_STATUS1_DDC_BUSHANG) {
-			ret = it66121_abort_ddc_ops(ctx);
-			if (ret)
-				return ret;
-		}
-
 		ret = it66121_preamble_ddc(ctx);
 		if (ret)
 			return ret;
@@ -585,8 +565,10 @@ static int it66121_get_edid_block(void *context, u8 *buf,
 		remain -= cnt;
 
 		ret = it66121_wait_ddc_ready(ctx);
-		if (ret)
+		if (ret) {
+			it66121_abort_ddc_ops(ctx);
 			return ret;
+		}
 
 		ret = regmap_noinc_read(ctx->regmap, IT66121_DDC_RD_FIFO_REG,
 					buf, cnt);
@@ -671,11 +653,7 @@ static int it66121_bridge_attach(struct drm_bridge *bridge,
 	/* Per programming manual, sleep here for bridge to settle */
 	msleep(50);
 
-	/* Start interrupts */
-	return regmap_write_bits(ctx->regmap, IT66121_INT_MASK1_REG,
-				 IT66121_INT_MASK1_DDC_NOACK |
-				 IT66121_INT_MASK1_DDC_FIFOERR |
-				 IT66121_INT_MASK1_DDC_BUSHANG, 0);
+	return 0;
 }
 
 static int it66121_set_mute(struct it66121_ctx *ctx, bool mute)
@@ -926,21 +904,14 @@ static irqreturn_t it66121_irq_threaded_handler(int irq, void *dev_id)
 	ret = regmap_read(ctx->regmap, IT66121_INT_STATUS1_REG, &val);
 	if (ret) {
 		dev_err(dev, "Cannot read STATUS1_REG %d\n", ret);
-	} else {
-		if (val & IT66121_INT_STATUS1_DDC_FIFOERR)
-			it66121_clear_ddc_fifo(ctx);
-		if (val & (IT66121_INT_STATUS1_DDC_BUSHANG |
-			   IT66121_INT_STATUS1_DDC_NOACK))
-			it66121_abort_ddc_ops(ctx);
-		if (val & IT66121_INT_STATUS1_HPD_STATUS) {
-			regmap_write_bits(ctx->regmap, IT66121_INT_CLR1_REG,
-					  IT66121_INT_CLR1_HPD, IT66121_INT_CLR1_HPD);
+	} else if (val & IT66121_INT_STATUS1_HPD_STATUS) {
+		regmap_write_bits(ctx->regmap, IT66121_INT_CLR1_REG,
+				  IT66121_INT_CLR1_HPD, IT66121_INT_CLR1_HPD);
 
-			status = it66121_is_hpd_detect(ctx) ? connector_status_connected
-							    : connector_status_disconnected;
+		status = it66121_is_hpd_detect(ctx) ? connector_status_connected
+			: connector_status_disconnected;
 
-			event = true;
-		}
+		event = true;
 	}
 
 	regmap_write_bits(ctx->regmap, IT66121_SYS_STATUS_REG,