Commit a6706447 authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
Browse files

media: pulse8-cec: locking improvements 



Drop the write_lock, rename config_lock to plain lock since this
now locks access to the adapter. Use 'lock' when transmitting
a message, ensuring that nothing interferes with the transmit.

Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent cea28e7a

drivers/media/usb/pulse8-cec/pulse8-cec.c

+26 −21
Original line number Diff line number Diff line
@@ -180,8 +180,8 @@ struct pulse8 { 
	unsigned int idx;

	bool escape;

	bool started;

	struct mutex config_lock;

	struct mutex write_lock;

	/* locks access to the adapter */

	struct mutex lock;

	bool config_pending;

	bool restoring_config;

	bool autonomous;
@@ -244,22 +244,17 @@ static int pulse8_send_and_wait(struct pulse8 *pulse8, 
	u8 cmd_sc[2];

	int err;



	mutex_lock(&pulse8->write_lock);

	err = pulse8_send_and_wait_once(pulse8, cmd, cmd_len, response, size);

	if (err != -ENOTTY)

		return err;



	if (err == -ENOTTY) {

	cmd_sc[0] = MSGCODE_SET_CONTROLLED;

	cmd_sc[1] = 1;

	err = pulse8_send_and_wait_once(pulse8, cmd_sc, 2,

					MSGCODE_COMMAND_ACCEPTED, 1);

		if (err)

			goto unlock;

	if (!err)

		err = pulse8_send_and_wait_once(pulse8, cmd, cmd_len,

						response, size);

	}



unlock:

	mutex_unlock(&pulse8->write_lock);

	return err == -ENOTTY ? -EIO : err;

}
@@ -275,15 +270,21 @@ static void pulse8_irq_work_handler(struct work_struct *work) 
		cec_received_msg(pulse8->adap, &pulse8->rx_msg);

		break;

	case MSGCODE_TRANSMIT_SUCCEEDED:

		mutex_lock(&pulse8->lock);

		cec_transmit_attempt_done(pulse8->adap, CEC_TX_STATUS_OK);

		mutex_unlock(&pulse8->lock);

		break;

	case MSGCODE_TRANSMIT_FAILED_ACK:

		mutex_lock(&pulse8->lock);

		cec_transmit_attempt_done(pulse8->adap, CEC_TX_STATUS_NACK);

		mutex_unlock(&pulse8->lock);

		break;

	case MSGCODE_TRANSMIT_FAILED_LINE:

	case MSGCODE_TRANSMIT_FAILED_TIMEOUT_DATA:

	case MSGCODE_TRANSMIT_FAILED_TIMEOUT_LINE:

		mutex_lock(&pulse8->lock);

		cec_transmit_attempt_done(pulse8->adap, CEC_TX_STATUS_ERROR);

		mutex_unlock(&pulse8->lock);

		break;

	}

}
@@ -373,10 +374,12 @@ static int pulse8_cec_adap_enable(struct cec_adapter *adap, bool enable) 
	u8 cmd[16];

	int err;



	mutex_lock(&pulse8->lock);

	cmd[0] = MSGCODE_SET_CONTROLLED;

	cmd[1] = enable;

	err = pulse8_send_and_wait(pulse8, cmd, 2,

				   MSGCODE_COMMAND_ACCEPTED, 1);

	mutex_unlock(&pulse8->lock);

	return enable ? err : 0;

}
@@ -388,7 +391,7 @@ static int pulse8_cec_adap_log_addr(struct cec_adapter *adap, u8 log_addr) 
	u8 cmd[16];

	int err = 0;



	mutex_lock(&pulse8->config_lock);

	mutex_lock(&pulse8->lock);

	if (log_addr != CEC_LOG_ADDR_INVALID)

		mask = 1 << log_addr;

	cmd[0] = MSGCODE_SET_ACK_MASK;
@@ -496,7 +499,7 @@ unlock: 
		pulse8->restoring_config = false;

	else

		pulse8->config_pending = true;

	mutex_unlock(&pulse8->config_lock);

	mutex_unlock(&pulse8->lock);

	return log_addr == CEC_LOG_ADDR_INVALID ? 0 : err;

}
@@ -508,6 +511,7 @@ static int pulse8_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, 
	unsigned int i;

	int err;



	mutex_lock(&pulse8->lock);

	cmd[0] = MSGCODE_TRANSMIT_IDLETIME;

	cmd[1] = signal_free_time;

	err = pulse8_send_and_wait(pulse8, cmd, 2,
@@ -537,6 +541,7 @@ static int pulse8_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, 
		}

	}



	mutex_unlock(&pulse8->lock);

	return err;

}
@@ -699,14 +704,14 @@ static void pulse8_ping_eeprom_work_handler(struct work_struct *work) 
	u8 cmd;



	schedule_delayed_work(&pulse8->ping_eeprom_work, PING_PERIOD);

	mutex_lock(&pulse8->lock);

	cmd = MSGCODE_PING;

	pulse8_send_and_wait(pulse8, &cmd, 1,

			     MSGCODE_COMMAND_ACCEPTED, 0);



	if (pulse8->vers < 2)

		return;

		goto unlock;



	mutex_lock(&pulse8->config_lock);

	if (pulse8->config_pending && persistent_config) {

		dev_dbg(pulse8->dev, "writing pending config to EEPROM\n");

		cmd = MSGCODE_WRITE_EEPROM;
@@ -716,7 +721,8 @@ static void pulse8_ping_eeprom_work_handler(struct work_struct *work) 
		else

			pulse8->config_pending = false;

	}

	mutex_unlock(&pulse8->config_lock);

unlock:

	mutex_unlock(&pulse8->lock);

}



static int pulse8_connect(struct serio *serio, struct serio_driver *drv)
@@ -742,8 +748,7 @@ static int pulse8_connect(struct serio *serio, struct serio_driver *drv) 
	pulse8->dev = &serio->dev;

	serio_set_drvdata(serio, pulse8);

	INIT_WORK(&pulse8->work, pulse8_irq_work_handler);

	mutex_init(&pulse8->write_lock);

	mutex_init(&pulse8->config_lock);

	mutex_init(&pulse8->lock);

	pulse8->config_pending = false;



	err = serio_open(serio, drv);

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