[media] cec: add cec_transmit_attempt_done helper function

A simpler variant of cec_transmit_done to be used where the HW does
just a single attempt at a transmit. So if the status indicates an
error, then the corresponding error count will always be 1 and this
function figures that out based on the status argument.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

Documentation/media/kapi/cec-core.rst

@@ -194,6 +194,11 @@ When a transmit finished (successfully or otherwise):
 	void cec_transmit_done(struct cec_adapter *adap, u8 status, u8 arb_lost_cnt,
 		       u8 nack_cnt, u8 low_drive_cnt, u8 error_cnt);
 
+or:
+
+.. c:function::
+	void cec_transmit_attempt_done(struct cec_adapter *adap, u8 status);
+
 The status can be one of:
 
 CEC_TX_STATUS_OK:
@@ -231,6 +236,11 @@ to 1, if the hardware does support retry then either set these counters to
 0 if the hardware provides no feedback of which errors occurred and how many
 times, or fill in the correct values as reported by the hardware.
 
+The cec_transmit_attempt_done() function is a helper for cases where the
+hardware never retries, so the transmit is always for just a single
+attempt. It will call cec_transmit_done() in turn, filling in 1 for the
+count argument corresponding to the status. Or all 0 if the status was OK.
+
 When a CEC message was received:
 
 .. c:function::

drivers/media/cec/cec-adap.c

@@ -553,6 +553,32 @@ unlock:
 }
 EXPORT_SYMBOL_GPL(cec_transmit_done);
 
+void cec_transmit_attempt_done(struct cec_adapter *adap, u8 status)
+{
+	switch (status) {
+	case CEC_TX_STATUS_OK:
+		cec_transmit_done(adap, status, 0, 0, 0, 0);
+		return;
+	case CEC_TX_STATUS_ARB_LOST:
+		cec_transmit_done(adap, status, 1, 0, 0, 0);
+		return;
+	case CEC_TX_STATUS_NACK:
+		cec_transmit_done(adap, status, 0, 1, 0, 0);
+		return;
+	case CEC_TX_STATUS_LOW_DRIVE:
+		cec_transmit_done(adap, status, 0, 0, 1, 0);
+		return;
+	case CEC_TX_STATUS_ERROR:
+		cec_transmit_done(adap, status, 0, 0, 0, 1);
+		return;
+	default:
+		/* Should never happen */
+		WARN(1, "cec-%s: invalid status 0x%02x\n", adap->name, status);
+		return;
+	}
+}
+EXPORT_SYMBOL_GPL(cec_transmit_attempt_done);
+
 /*
  * Called when waiting for a reply times out.
  */

include/media/cec.h

@@ -227,6 +227,12 @@ int cec_transmit_msg(struct cec_adapter *adap, struct cec_msg *msg,
 /* Called by the adapter */
 void cec_transmit_done(struct cec_adapter *adap, u8 status, u8 arb_lost_cnt,
 		       u8 nack_cnt, u8 low_drive_cnt, u8 error_cnt);
+/*
+ * Simplified version of cec_transmit_done for hardware that doesn't retry
+ * failed transmits. So this is always just one attempt in which case
+ * the status is sufficient.
+ */
+void cec_transmit_attempt_done(struct cec_adapter *adap, u8 status);
 void cec_received_msg(struct cec_adapter *adap, struct cec_msg *msg);
 
 /**