media: cec: core: add new CEC_MSG_FL_REPLY_VENDOR_ID flag

If this flag is set, then the reply is expected to consist of
the CEC_MSG_VENDOR_COMMAND_WITH_ID opcode followed by the Vendor ID (as
used in bytes 1-4 of the message), followed by the struct cec_msg reply
field.

Note that this assumes that the byte after the Vendor ID is a
vendor-specific opcode.

This flag makes it easier to wait for replies to vendor commands,
using the same CEC framework support for waiting for regular replies.

Support for this flag is indicated by setting the new
CEC_CAP_REPLY_VENDOR_ID capability.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

2 files changed, 38 insertions, 16 deletions

diff --git a/drivers/media/cec/core/cec-adap.c b/drivers/media/cec/core/cec-adap.c
index da09834990b8..c81b1ed7c08a 100644
--- a/drivers/media/cec/core/cec-adap.c
+++ b/drivers/media/cec/core/cec-adap.c
@@ -673,8 +673,9 @@ void cec_transmit_done_ts(struct cec_adapter *adap, u8 status,
 		/* Retry this message */
 		data->attempts -= attempts_made;
 		if (msg->timeout)
-			dprintk(2, "retransmit: %*ph (attempts: %d, wait for 0x%02x)\n",
-				msg->len, msg->msg, data->attempts, msg->reply);
+			dprintk(2, "retransmit: %*ph (attempts: %d, wait for %*ph)\n",
+				msg->len, msg->msg, data->attempts,
+				data->match_len, data->match_reply);
 		else
 			dprintk(2, "retransmit: %*ph (attempts: %d)\n",
 				msg->len, msg->msg, data->attempts);
@@ -780,6 +781,7 @@ int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg,
 {
 	struct cec_data *data;
 	bool is_raw = msg_is_raw(msg);
+	bool reply_vendor_id = msg->flags & CEC_MSG_FL_REPLY_VENDOR_ID;
 	int err;
 
 	if (adap->devnode.unregistered)
@@ -794,12 +796,13 @@ int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg,
 	msg->tx_low_drive_cnt = 0;
 	msg->tx_error_cnt = 0;
 	msg->sequence = 0;
+	msg->flags &= CEC_MSG_FL_REPLY_TO_FOLLOWERS | CEC_MSG_FL_RAW |
+		      CEC_MSG_FL_REPLY_VENDOR_ID;
 
-	if (msg->reply && msg->timeout == 0) {
+	if ((reply_vendor_id || msg->reply) && msg->timeout == 0) {
 		/* Make sure the timeout isn't 0. */
 		msg->timeout = 1000;
 	}
-	msg->flags &= CEC_MSG_FL_REPLY_TO_FOLLOWERS | CEC_MSG_FL_RAW;
 
 	if (!msg->timeout)
 		msg->flags &= ~CEC_MSG_FL_REPLY_TO_FOLLOWERS;
@@ -809,6 +812,11 @@ int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg,
 		dprintk(1, "%s: invalid length %d\n", __func__, msg->len);
 		return -EINVAL;
 	}
+	if (reply_vendor_id &&
+	    (msg->len < 6 || msg->msg[1] != CEC_MSG_VENDOR_COMMAND_WITH_ID)) {
+		dprintk(1, "%s: message too short or not <Vendor Command With ID>\n", __func__);
+		return -EINVAL;
+	}
 
 	memset(msg->msg + msg->len, 0, sizeof(msg->msg) - msg->len);
 
@@ -900,8 +908,9 @@ int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg,
 				__func__);
 			return -ENONET;
 		}
-		if (msg->reply) {
-			dprintk(1, "%s: invalid msg->reply\n", __func__);
+		if (reply_vendor_id || msg->reply) {
+			dprintk(1, "%s: adapter is unconfigured so reply is not supported\n",
+				__func__);
 			return -EINVAL;
 		}
 	}
@@ -923,6 +932,14 @@ int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg,
 	data->fh = fh;
 	data->adap = adap;
 	data->blocking = block;
+	if (reply_vendor_id) {
+		memcpy(data->match_reply, msg->msg + 1, 4);
+		data->match_reply[4] = msg->reply;
+		data->match_len = 5;
+	} else if (msg->timeout) {
+		data->match_reply[0] = msg->reply;
+		data->match_len = 1;
+	}
 
 	init_completion(&data->c);
 	INIT_DELAYED_WORK(&data->work, cec_wait_timeout);
@@ -1211,13 +1228,15 @@ void cec_received_msg_ts(struct cec_adapter *adap,
 			if (!abort && dst->msg[1] == CEC_MSG_INITIATE_ARC &&
 			    (cmd == CEC_MSG_REPORT_ARC_INITIATED ||
 			     cmd == CEC_MSG_REPORT_ARC_TERMINATED) &&
-			    (dst->reply == CEC_MSG_REPORT_ARC_INITIATED ||
-			     dst->reply == CEC_MSG_REPORT_ARC_TERMINATED))
+			    (data->match_reply[0] == CEC_MSG_REPORT_ARC_INITIATED ||
+			     data->match_reply[0] == CEC_MSG_REPORT_ARC_TERMINATED)) {
 				dst->reply = cmd;
+				data->match_reply[0] = cmd;
+			}
 
 			/* Does the command match? */
 			if ((abort && cmd != dst->msg[1]) ||
-			    (!abort && cmd != dst->reply))
+			    (!abort && memcmp(data->match_reply, msg->msg + 1, data->match_len)))
 				continue;
 
 			/* Does the addressing match? */
@@ -2318,18 +2337,21 @@ int cec_adap_status(struct seq_file *file, void *priv)
 	}
 	data = adap->transmitting;
 	if (data)
-		seq_printf(file, "transmitting message: %*ph (reply: %02x, timeout: %ums)\n",
-			   data->msg.len, data->msg.msg, data->msg.reply,
+		seq_printf(file, "transmitting message: %*ph (reply: %*ph, timeout: %ums)\n",
+			   data->msg.len, data->msg.msg,
+			   data->match_len, data->match_reply,
 			   data->msg.timeout);
 	seq_printf(file, "pending transmits: %u\n", adap->transmit_queue_sz);
 	list_for_each_entry(data, &adap->transmit_queue, list) {
-		seq_printf(file, "queued tx message: %*ph (reply: %02x, timeout: %ums)\n",
-			   data->msg.len, data->msg.msg, data->msg.reply,
+		seq_printf(file, "queued tx message: %*ph (reply: %*ph, timeout: %ums)\n",
+			   data->msg.len, data->msg.msg,
+			   data->match_len, data->match_reply,
 			   data->msg.timeout);
 	}
 	list_for_each_entry(data, &adap->wait_queue, list) {
-		seq_printf(file, "message waiting for reply: %*ph (reply: %02x, timeout: %ums)\n",
-			   data->msg.len, data->msg.msg, data->msg.reply,
+		seq_printf(file, "message waiting for reply: %*ph (reply: %*ph, timeout: %ums)\n",
+			   data->msg.len, data->msg.msg,
+			   data->match_len, data->match_reply,
 			   data->msg.timeout);
 	}
 
diff --git a/drivers/media/cec/core/cec-core.c b/drivers/media/cec/core/cec-core.c
index 6f940df0230c..e0756826d629 100644
--- a/drivers/media/cec/core/cec-core.c
+++ b/drivers/media/cec/core/cec-core.c
@@ -273,7 +273,7 @@ struct cec_adapter *cec_allocate_adapter(const struct cec_adap_ops *ops,
 	adap->cec_pin_is_high = true;
 	adap->log_addrs.cec_version = CEC_OP_CEC_VERSION_2_0;
 	adap->log_addrs.vendor_id = CEC_VENDOR_ID_NONE;
-	adap->capabilities = caps;
+	adap->capabilities = caps | CEC_CAP_REPLY_VENDOR_ID;
 	if (debug_phys_addr)
 		adap->capabilities |= CEC_CAP_PHYS_ADDR;
 	adap->needs_hpd = caps & CEC_CAP_NEEDS_HPD;