Commit 5e9c1662 authored by Dmitry Baryshkov's avatar Dmitry Baryshkov Committed by Greg Kroah-Hartman
Browse files

usb: typec: ucsi: rework command execution functions 



Rework command execution code to remove recursive calls of
ucsi_exec_command. This also streamlines the sync_control / read(CCI)
read (MESSAGE_IN) sequence, allowing further rework of the command code.

Tested-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240627-ucsi-rework-interface-v4-4-289ddc6874c7@linaro.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 467399d9

drivers/usb/typec/ucsi/ucsi.c

+66 −72
Original line number Diff line number Diff line
@@ -63,27 +63,76 @@ static int ucsi_acknowledge(struct ucsi *ucsi, bool conn_ack) 
	return ucsi->ops->sync_control(ucsi, ctrl);

}



static int ucsi_exec_command(struct ucsi *ucsi, u64 command);



static int ucsi_read_error(struct ucsi *ucsi, u8 connector_num)

static int ucsi_run_command(struct ucsi *ucsi, u64 command, u32 *cci,

			    void *data, size_t size, bool conn_ack)

{

	u64 command;

	u16 error;

	int ret;



	command = UCSI_GET_ERROR_STATUS | UCSI_CONNECTOR_NUMBER(connector_num);

	ret = ucsi_exec_command(ucsi, command);

	if (ret < 0)

	*cci = 0;



	ret = ucsi->ops->sync_control(ucsi, command);

	if (ret)

		return ret;



	ret = ucsi_read_message_in(ucsi, &error, sizeof(error));

	ret = ucsi->ops->read_cci(ucsi, cci);

	if (ret)

		return ret;



	if (*cci & UCSI_CCI_BUSY)

		return -EBUSY;



	if (!(*cci & UCSI_CCI_COMMAND_COMPLETE))

		return -EIO;



	if (*cci & UCSI_CCI_NOT_SUPPORTED) {

		if (ucsi_acknowledge(ucsi, false) < 0)

			dev_err(ucsi->dev,

				"ACK of unsupported command failed\n");

		return -EOPNOTSUPP;

	}



	if (*cci & UCSI_CCI_ERROR) {

		/* Acknowledge the command that failed */

		ret = ucsi_acknowledge(ucsi, false);

		return ret ? ret : -EIO;

	}



	if (data) {

		ret = ucsi_read_message_in(ucsi, data, size);

		if (ret)

			return ret;

	}



	ret = ucsi_acknowledge(ucsi, conn_ack);

	if (ret)

		return ret;



	return 0;

}



static int ucsi_read_error(struct ucsi *ucsi, u8 connector_num)

{

	u64 command;

	u16 error;

	u32 cci;

	int ret;



	command = UCSI_GET_ERROR_STATUS | UCSI_CONNECTOR_NUMBER(connector_num);

	ret = ucsi_run_command(ucsi, command, &cci,

			       &error, sizeof(error), false);



	if (cci & UCSI_CCI_BUSY) {

		ret = ucsi_run_command(ucsi, UCSI_CANCEL, &cci, NULL, 0, false);



		return ret ? ret : -EBUSY;

	}



	if (ret < 0)

		return ret;



	if (cci & UCSI_CCI_ERROR)

		return -EIO;



	switch (error) {

	case UCSI_ERROR_INCOMPATIBLE_PARTNER:

		return -EOPNOTSUPP;
@@ -129,7 +178,8 @@ static int ucsi_read_error(struct ucsi *ucsi, u8 connector_num) 
	return -EIO;

}



static int ucsi_exec_command(struct ucsi *ucsi, u64 cmd)

static int ucsi_send_command_common(struct ucsi *ucsi, u64 cmd,

				    void *data, size_t size, bool conn_ack)

{

	u8 connector_num;

	u32 cci;
@@ -155,73 +205,17 @@ static int ucsi_exec_command(struct ucsi *ucsi, u64 cmd) 
		connector_num = 0;

	}



	ret = ucsi->ops->sync_control(ucsi, cmd);

	if (ret)

		return ret;



	ret = ucsi->ops->read_cci(ucsi, &cci);

	if (ret)

		return ret;



	if (cmd != UCSI_CANCEL && cci & UCSI_CCI_BUSY)

		return ucsi_exec_command(ucsi, UCSI_CANCEL);



	if (!(cci & UCSI_CCI_COMMAND_COMPLETE))

		return -EIO;



	if (cci & UCSI_CCI_NOT_SUPPORTED) {

		if (ucsi_acknowledge(ucsi, false) < 0)

			dev_err(ucsi->dev,

				"ACK of unsupported command failed\n");

		return -EOPNOTSUPP;

	}



	if (cci & UCSI_CCI_ERROR) {

		/* Acknowledge the command that failed */

		ret = ucsi_acknowledge(ucsi, false);

		if (ret)

			return ret;



		if (cmd == UCSI_GET_ERROR_STATUS)

			return -EIO;



		return ucsi_read_error(ucsi, connector_num);

	}



	if (cmd == UCSI_CANCEL && cci & UCSI_CCI_CANCEL_COMPLETE) {

		ret = ucsi_acknowledge(ucsi, false);

		return ret ? ret : -EBUSY;

	}



	return UCSI_CCI_LENGTH(cci);

}



static int ucsi_send_command_common(struct ucsi *ucsi, u64 command,

				    void *data, size_t size, bool conn_ack)

{

	u8 length;

	int ret;



	mutex_lock(&ucsi->ppm_lock);



	ret = ucsi_exec_command(ucsi, command);

	if (ret < 0)

		goto out;



	length = ret;



	if (data) {

		ret = ucsi_read_message_in(ucsi, data, size);

		if (ret)

			goto out;

	ret = ucsi_run_command(ucsi, cmd, &cci, data, size, conn_ack);

	if (cci & UCSI_CCI_BUSY) {

		ret = ucsi_run_command(ucsi, UCSI_CANCEL, &cci, NULL, 0, false);

		return ret ? ret : -EBUSY;

	}



	ret = ucsi_acknowledge(ucsi, conn_ack);

	if (ret)

		goto out;

	if (cci & UCSI_CCI_ERROR)

		return ucsi_read_error(ucsi, connector_num);



	ret = length;

out:

	mutex_unlock(&ucsi->ppm_lock);

	return ret;

}