diff --git a/drivers/mailbox/qcom-cpucp-mbox.c b/drivers/mailbox/qcom-cpucp-mbox.c
index 0f7fe189e8b1..298b357c0f9a 100644
--- a/drivers/mailbox/qcom-cpucp-mbox.c
+++ b/drivers/mailbox/qcom-cpucp-mbox.c
@@ -117,6 +117,14 @@ static int qcom_cpucp_mbox_send_data(struct mbox_chan *chan, void *data)
 	unsigned long chan_id = channel_number(chan);
 	u32 *val = data;
 
+	/*
+	 * mailbox_clear_channel() calls mbox_send_message() with NULL data to
+	 * signal the remote side that the channel has been cleared.  Nothing
+	 * needs to be written to the TX register in that case, so just return.
+	 */
+	if (!val)
+		return 0;
+
 	writel(*val, cpucp->tx_base + APSS_CPUCP_TX_MBOX_CMD(chan_id) + APSS_CPUCP_MBOX_CMD_OFF);
 
 	return 0;