[PATCH v3 06/18] media: siano: Refactor struct sms_msg_data

[Ricardo Ribalda]

Replace a single element array with a single element field.

The endianness conversion code seems to support multiple elements. To
avoid changing behavior a pointer to the single element has been used.

This is safer than moving to a flex array, because in that case the
structure size changes.

This fixes the following cocci warning:
drivers/media/common/siano/smscoreapi.h:619:5-13: WARNING use flexible-array member instead (https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays)

Signed-off-by: Ricardo Ribalda <ribalda at chromium.org>
---
 drivers/media/common/siano/smscoreapi.c  | 10 +++++-----
 drivers/media/common/siano/smscoreapi.h  |  2 +-
 drivers/media/common/siano/smsdvb-main.c |  4 ++--
 drivers/media/common/siano/smsendian.c   |  8 +++++---
 4 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/drivers/media/common/siano/smscoreapi.c b/drivers/media/common/siano/smscoreapi.c
index 7ebcb10126c9..b6f1eb5dbbdf 100644
--- a/drivers/media/common/siano/smscoreapi.c
+++ b/drivers/media/common/siano/smscoreapi.c
@@ -839,7 +839,7 @@ static int smscore_configure_board(struct smscore_device_t *coredev)
 		mtu_msg.x_msg_header.msg_flags = 0;
 		mtu_msg.x_msg_header.msg_type = MSG_SMS_SET_MAX_TX_MSG_LEN_REQ;
 		mtu_msg.x_msg_header.msg_length = sizeof(mtu_msg);
-		mtu_msg.msg_data[0] = board->mtu;
+		mtu_msg.msg_data = board->mtu;
 
 		coredev->sendrequest_handler(coredev->context, &mtu_msg,
 					     sizeof(mtu_msg));
@@ -852,7 +852,7 @@ static int smscore_configure_board(struct smscore_device_t *coredev)
 		SMS_INIT_MSG(&crys_msg.x_msg_header,
 				MSG_SMS_NEW_CRYSTAL_REQ,
 				sizeof(crys_msg));
-		crys_msg.msg_data[0] = board->crystal;
+		crys_msg.msg_data = board->crystal;
 
 		coredev->sendrequest_handler(coredev->context, &crys_msg,
 					     sizeof(crys_msg));
@@ -1306,7 +1306,7 @@ static int smscore_init_device(struct smscore_device_t *coredev, int mode)
 	msg = (struct sms_msg_data *)SMS_ALIGN_ADDRESS(buffer);
 	SMS_INIT_MSG(&msg->x_msg_header, MSG_SMS_INIT_DEVICE_REQ,
 			sizeof(struct sms_msg_data));
-	msg->msg_data[0] = mode;
+	msg->msg_data = mode;
 
 	rc = smscore_sendrequest_and_wait(coredev, msg,
 			msg->x_msg_header. msg_length,
@@ -1394,7 +1394,7 @@ int smscore_set_device_mode(struct smscore_device_t *coredev, int mode)
 
 			SMS_INIT_MSG(&msg->x_msg_header, MSG_SMS_INIT_DEVICE_REQ,
 				     sizeof(struct sms_msg_data));
-			msg->msg_data[0] = mode;
+			msg->msg_data = mode;
 
 			rc = smscore_sendrequest_and_wait(
 				coredev, msg, msg->x_msg_header.msg_length,
@@ -1554,7 +1554,7 @@ void smscore_onresponse(struct smscore_device_t *coredev,
 			struct sms_msg_data *validity = (struct sms_msg_data *) phdr;
 
 			pr_debug("MSG_SMS_DATA_VALIDITY_RES, checksum = 0x%x\n",
-				validity->msg_data[0]);
+				validity->msg_data);
 			complete(&coredev->data_validity_done);
 			break;
 		}
diff --git a/drivers/media/common/siano/smscoreapi.h b/drivers/media/common/siano/smscoreapi.h
index f8789ee0d554..46dc74ac9318 100644
--- a/drivers/media/common/siano/smscoreapi.h
+++ b/drivers/media/common/siano/smscoreapi.h
@@ -616,7 +616,7 @@ struct sms_msg_hdr {
 
 struct sms_msg_data {
 	struct sms_msg_hdr x_msg_header;
-	u32 msg_data[1];
+	u32 msg_data;
 };
 
 struct sms_msg_data2 {
diff --git a/drivers/media/common/siano/smsdvb-main.c b/drivers/media/common/siano/smsdvb-main.c
index d893a0e4672b..44d8fe8b220e 100644
--- a/drivers/media/common/siano/smsdvb-main.c
+++ b/drivers/media/common/siano/smsdvb-main.c
@@ -689,7 +689,7 @@ static int smsdvb_start_feed(struct dvb_demux_feed *feed)
 	pid_msg.x_msg_header.msg_flags = 0;
 	pid_msg.x_msg_header.msg_type  = MSG_SMS_ADD_PID_FILTER_REQ;
 	pid_msg.x_msg_header.msg_length = sizeof(pid_msg);
-	pid_msg.msg_data[0] = feed->pid;
+	pid_msg.msg_data = feed->pid;
 
 	return smsclient_sendrequest(client->smsclient,
 				     &pid_msg, sizeof(pid_msg));
@@ -711,7 +711,7 @@ static int smsdvb_stop_feed(struct dvb_demux_feed *feed)
 	pid_msg.x_msg_header.msg_flags = 0;
 	pid_msg.x_msg_header.msg_type  = MSG_SMS_REMOVE_PID_FILTER_REQ;
 	pid_msg.x_msg_header.msg_length = sizeof(pid_msg);
-	pid_msg.msg_data[0] = feed->pid;
+	pid_msg.msg_data = feed->pid;
 
 	return smsclient_sendrequest(client->smsclient,
 				     &pid_msg, sizeof(pid_msg));
diff --git a/drivers/media/common/siano/smsendian.c b/drivers/media/common/siano/smsendian.c
index a3573814919b..b957970c7d97 100644
--- a/drivers/media/common/siano/smsendian.c
+++ b/drivers/media/common/siano/smsendian.c
@@ -20,11 +20,12 @@ void smsendian_handle_tx_message(void *buffer)
 	struct sms_msg_data *msg = buffer;
 	int i;
 	int msg_words;
+	u32 *msg_data = &msg->msg_data;
 
 	switch (msg->x_msg_header.msg_type) {
 	case MSG_SMS_DATA_DOWNLOAD_REQ:
 	{
-		msg->msg_data[0] = le32_to_cpu((__force __le32)(msg->msg_data[0]));
+		msg->msg_data = le32_to_cpu((__force __le32)(msg->msg_data));
 		break;
 	}
 
@@ -33,7 +34,7 @@ void smsendian_handle_tx_message(void *buffer)
 				sizeof(struct sms_msg_hdr))/4;
 
 		for (i = 0; i < msg_words; i++)
-			msg->msg_data[i] = le32_to_cpu((__force __le32)msg->msg_data[i]);
+			msg_data[i] = le32_to_cpu((__force __le32)msg_data[i]);
 
 		break;
 	}
@@ -66,11 +67,12 @@ void smsendian_handle_rx_message(void *buffer)
 
 	default:
 	{
+		u32 *msg_data = &msg->msg_data;
 		msg_words = (msg->x_msg_header.msg_length -
 				sizeof(struct sms_msg_hdr))/4;
 
 		for (i = 0; i < msg_words; i++)
-			msg->msg_data[i] = le32_to_cpu((__force __le32)msg->msg_data[i]);
+			msg_data[i] = le32_to_cpu((__force __le32)msg_data[i]);
 
 		break;
 	}

-- 
2.45.1.288.g0e0cd299f1-goog