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-rw-r--r--drivers/i2c/busses/i2c-uniphier-f.c17
1 files changed, 14 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c
index dd384743dbbd..fad2b00a8c8c 100644
--- a/drivers/i2c/busses/i2c-uniphier-f.c
+++ b/drivers/i2c/busses/i2c-uniphier-f.c
@@ -173,8 +173,6 @@ static irqreturn_t uniphier_fi2c_interrupt(int irq, void *dev_id)
 		"interrupt: enabled_irqs=%04x, irq_status=%04x\n",
 		priv->enabled_irqs, irq_status);
 
-	uniphier_fi2c_clear_irqs(priv, irq_status);
-
 	if (irq_status & UNIPHIER_FI2C_INT_STOP)
 		goto complete;
 
@@ -214,7 +212,13 @@ static irqreturn_t uniphier_fi2c_interrupt(int irq, void *dev_id)
 
 	if (irq_status & (UNIPHIER_FI2C_INT_RF | UNIPHIER_FI2C_INT_RB)) {
 		uniphier_fi2c_drain_rxfifo(priv);
-		if (!priv->len)
+		/*
+		 * If the number of bytes to read is multiple of the FIFO size
+		 * (msg->len == 8, 16, 24, ...), the INT_RF bit is set a little
+		 * earlier than INT_RB. We wait for INT_RB to confirm the
+		 * completion of the current message.
+		 */
+		if (!priv->len && (irq_status & UNIPHIER_FI2C_INT_RB))
 			goto data_done;
 
 		if (unlikely(priv->flags & UNIPHIER_FI2C_MANUAL_NACK)) {
@@ -253,6 +257,13 @@ complete:
 	}
 
 handled:
+	/*
+	 * This controller makes a pause while any bit of the IRQ status is
+	 * asserted. Clear the asserted bit to kick the controller just before
+	 * exiting the handler.
+	 */
+	uniphier_fi2c_clear_irqs(priv, irq_status);
+
 	spin_unlock(&priv->lock);
 
 	return IRQ_HANDLED;