Commit f9d0ecbf authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
Browse files

media: cec: correctly pass on reply results 



The results of non-blocking transmits were not correctly communicated
to userspace.

Specifically:

1) if a non-blocking transmit was canceled, then rx_status wasn't set to 0
   as it should.
2) if the non-blocking transmit succeeded, but the corresponding reply
   never arrived (aborted or timed out), then tx_status wasn't set to 0
   as it should, and rx_status was hardcoded to ABORTED instead of the
   actual reason, such as TIMEOUT. In addition, adap->ops->received() was
   never called, so drivers that want to do message processing themselves
   would not be informed of the failed reply.

Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@kernel.org>
parent 590a8e56

drivers/media/cec/core/cec-adap.c

+30 −18
Original line number Diff line number Diff line
@@ -366,38 +366,48 @@ static void cec_data_completed(struct cec_data *data) 
/*

 * A pending CEC transmit needs to be cancelled, either because the CEC

 * adapter is disabled or the transmit takes an impossibly long time to

 * finish.

 * finish, or the reply timed out.

 *

 * This function is called with adap->lock held.

 */

static void cec_data_cancel(struct cec_data *data, u8 tx_status)

static void cec_data_cancel(struct cec_data *data, u8 tx_status, u8 rx_status)

{

	struct cec_adapter *adap = data->adap;



	/*

	 * It's either the current transmit, or it is a pending

	 * transmit. Take the appropriate action to clear it.

	 */

	if (data->adap->transmitting == data) {

		data->adap->transmitting = NULL;

	if (adap->transmitting == data) {

		adap->transmitting = NULL;

	} else {

		list_del_init(&data->list);

		if (!(data->msg.tx_status & CEC_TX_STATUS_OK))

			if (!WARN_ON(!data->adap->transmit_queue_sz))

				data->adap->transmit_queue_sz--;

			if (!WARN_ON(!adap->transmit_queue_sz))

				adap->transmit_queue_sz--;

	}



	if (data->msg.tx_status & CEC_TX_STATUS_OK) {

		data->msg.rx_ts = ktime_get_ns();

		data->msg.rx_status = CEC_RX_STATUS_ABORTED;

		data->msg.rx_status = rx_status;

		if (!data->blocking)

			data->msg.tx_status = 0;

	} else {

		data->msg.tx_ts = ktime_get_ns();

		data->msg.tx_status |= tx_status |

				       CEC_TX_STATUS_MAX_RETRIES;

		data->msg.tx_error_cnt++;

		data->attempts = 0;

		if (!data->blocking)

			data->msg.rx_status = 0;

	}



	/* Queue transmitted message for monitoring purposes */

	cec_queue_msg_monitor(data->adap, &data->msg, 1);

	cec_queue_msg_monitor(adap, &data->msg, 1);



	if (!data->blocking && data->msg.sequence && adap->ops->received)

		/* Allow drivers to process the message first */

		adap->ops->received(adap, &data->msg);



	cec_data_completed(data);

}
@@ -418,7 +428,7 @@ static void cec_flush(struct cec_adapter *adap) 
	while (!list_empty(&adap->transmit_queue)) {

		data = list_first_entry(&adap->transmit_queue,

					struct cec_data, list);

		cec_data_cancel(data, CEC_TX_STATUS_ABORTED);

		cec_data_cancel(data, CEC_TX_STATUS_ABORTED, 0);

	}

	if (adap->transmitting)

		adap->transmit_in_progress_aborted = true;
@@ -426,7 +436,7 @@ static void cec_flush(struct cec_adapter *adap) 
	/* Cancel the pending timeout work. */

	list_for_each_entry_safe(data, n, &adap->wait_queue, list) {

		if (cancel_delayed_work(&data->work))

			cec_data_cancel(data, CEC_TX_STATUS_OK);

			cec_data_cancel(data, CEC_TX_STATUS_OK, CEC_RX_STATUS_ABORTED);

		/*

		 * If cancel_delayed_work returned false, then

		 * the cec_wait_timeout function is running,
@@ -516,7 +526,7 @@ int cec_thread_func(void *_adap) 
					adap->transmitting->msg.msg);

				/* Just give up on this. */

				cec_data_cancel(adap->transmitting,

						CEC_TX_STATUS_TIMEOUT);

						CEC_TX_STATUS_TIMEOUT, 0);

			} else {

				pr_warn("cec-%s: transmit timed out\n", adap->name);

			}
@@ -576,7 +586,7 @@ int cec_thread_func(void *_adap) 
		/* Tell the adapter to transmit, cancel on error */

		if (adap->ops->adap_transmit(adap, data->attempts,

					     signal_free_time, &data->msg))

			cec_data_cancel(data, CEC_TX_STATUS_ABORTED);

			cec_data_cancel(data, CEC_TX_STATUS_ABORTED, 0);

		else

			adap->transmit_in_progress = true;
@@ -738,9 +748,7 @@ static void cec_wait_timeout(struct work_struct *work) 


	/* Mark the message as timed out */

	list_del_init(&data->list);

	data->msg.rx_ts = ktime_get_ns();

	data->msg.rx_status = CEC_RX_STATUS_TIMEOUT;

	cec_data_completed(data);

	cec_data_cancel(data, CEC_TX_STATUS_OK, CEC_RX_STATUS_TIMEOUT);

unlock:

	mutex_unlock(&adap->lock);

}
@@ -926,8 +934,12 @@ int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg, 
	mutex_lock(&adap->lock);



	/* Cancel the transmit if it was interrupted */

	if (!data->completed)

		cec_data_cancel(data, CEC_TX_STATUS_ABORTED);

	if (!data->completed) {

		if (data->msg.tx_status & CEC_TX_STATUS_OK)

			cec_data_cancel(data, CEC_TX_STATUS_OK, CEC_RX_STATUS_ABORTED);

		else

			cec_data_cancel(data, CEC_TX_STATUS_ABORTED, 0);

	}



	/* The transmit completed (possibly with an error) */

	*msg = data->msg;
@@ -1603,7 +1615,7 @@ static void cec_activate_cnt_dec(struct cec_adapter *adap) 
	adap->transmit_in_progress = false;

	adap->transmit_in_progress_aborted = false;

	if (adap->transmitting)

		cec_data_cancel(adap->transmitting, CEC_TX_STATUS_ABORTED);

		cec_data_cancel(adap->transmitting, CEC_TX_STATUS_ABORTED, 0);

	mutex_unlock(&adap->devnode.lock);

}