Commit 23a34e3a authored by Tzung-Bi Shih's avatar Tzung-Bi Shih
Browse files

platform/chrome: cros_ec_proto: factor legacy out from cros_ec_prepare_tx() 



cros_ec_prepare_tx() mixed the code for both versions.  To be neat and to
make it clear, factor the legacy part out as a separate function, rename
the function, and update the comments.

Specifically,
- prepare_tx(), for current protocol version (i.e. 3).
- prepare_tx_legacy(), for protocol version <= 2.

Signed-off-by: default avatarTzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: default avatarGuenter Roeck <groeck@chromium.org>
Link: https://lore.kernel.org/r/20220518091814.2028579-3-tzungbi@kernel.org
parent db681eaf

drivers/platform/chrome/cros_ec_proto.c

+28 −23
Original line number Diff line number Diff line
@@ -52,7 +52,7 @@ static int cros_ec_map_error(uint32_t result) 
	return ret;

}



static int prepare_packet(struct cros_ec_device *ec_dev,

static int prepare_tx(struct cros_ec_device *ec_dev,

		      struct cros_ec_command *msg)

{

	struct ec_host_request *request;
@@ -85,6 +85,28 @@ static int prepare_packet(struct cros_ec_device *ec_dev, 
	return sizeof(*request) + msg->outsize;

}



static int prepare_tx_legacy(struct cros_ec_device *ec_dev,

			     struct cros_ec_command *msg)

{

	u8 *out;

	u8 csum;

	int i;



	if (msg->outsize > EC_PROTO2_MAX_PARAM_SIZE)

		return -EINVAL;



	out = ec_dev->dout;

	out[0] = EC_CMD_VERSION0 + msg->version;

	out[1] = msg->command;

	out[2] = msg->outsize;

	csum = out[0] + out[1] + out[2];

	for (i = 0; i < msg->outsize; i++)

		csum += out[EC_MSG_TX_HEADER_BYTES + i] = msg->data[i];

	out[EC_MSG_TX_HEADER_BYTES + msg->outsize] = csum;



	return EC_MSG_TX_PROTO_BYTES + msg->outsize;

}



static int send_command(struct cros_ec_device *ec_dev,

			struct cros_ec_command *msg)

{
@@ -161,35 +183,18 @@ static int send_command(struct cros_ec_device *ec_dev, 
 * @ec_dev: Device to register.

 * @msg: Message to write.

 *

 * This is intended to be used by all ChromeOS EC drivers, but at present

 * only SPI uses it. Once LPC uses the same protocol it can start using it.

 * I2C could use it now, with a refactor of the existing code.

 * This is used by all ChromeOS EC drivers to prepare the outgoing message

 * according to different protocol versions.

 *

 * Return: number of prepared bytes on success or negative error code.

 */

int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,

		       struct cros_ec_command *msg)

{

	u8 *out;

	u8 csum;

	int i;



	if (ec_dev->proto_version > 2)

		return prepare_packet(ec_dev, msg);

		return prepare_tx(ec_dev, msg);



	if (msg->outsize > EC_PROTO2_MAX_PARAM_SIZE)

		return -EINVAL;



	out = ec_dev->dout;

	out[0] = EC_CMD_VERSION0 + msg->version;

	out[1] = msg->command;

	out[2] = msg->outsize;

	csum = out[0] + out[1] + out[2];

	for (i = 0; i < msg->outsize; i++)

		csum += out[EC_MSG_TX_HEADER_BYTES + i] = msg->data[i];

	out[EC_MSG_TX_HEADER_BYTES + msg->outsize] = csum;



	return EC_MSG_TX_PROTO_BYTES + msg->outsize;

	return prepare_tx_legacy(ec_dev, msg);

}

EXPORT_SYMBOL(cros_ec_prepare_tx);