Commit 10aa801d authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

greybus: operation: create gb_operation_sync for sending "simple" messages 



Everyone keeps doing the same create/send/destroy logic all over the
place, so abstract that out to a simple function that can handle any
arbritrary request and/or response.  This will let us save lots of
duplicated logic in the protocol drivers.

Signed-off-by: default avatarGreg Kroah-Hartman <greg@kroah.com>
Reviewed-by: default avatarAlex Elder <elder@linaro.org>
parent 10c69399

drivers/staging/greybus/operation.c

+54 −0
Original line number Diff line number Diff line
@@ -624,6 +624,60 @@ void gb_operation_cancel(struct gb_operation *operation, int errno) 
	gb_message_cancel(operation->response);

}



/**

 * gb_operation_sync: implement a "simple" synchronous gb operation.

 * @connection: the Greybus connection to send this to

 * @type: the type of operation to send

 * @request: pointer to a memory buffer to copy the request from

 * @request_size: size of @request

 * @response: pointer to a memory buffer to copy the response to

 * @response_size: the size of @response.

 *

 * This function implements a simple synchronous Greybus operation.  It sends

 * the provided operation request and waits (sleeps) until the corresponding

 * operation response message has been successfully received, or an error

 * occurs.  @request and @response are buffers to hold the request and response

 * data respectively, and if they are not NULL, their size must be specified in

 * @request_size and @response_size.

 *

 * If a response payload is to come back, and @response is not NULL,

 * @response_size number of bytes will be copied into @response if the operation

 * is successful.

 *

 * If there is an error, the response buffer is left alone.

 */

int gb_operation_sync(struct gb_connection *connection, int type,

		      void *request, int request_size,

		      void *response, int response_size)

{

	struct gb_operation *operation;

	int ret;



	if ((response_size && !response) ||

	    (request_size && !request))

		return -EINVAL;



	operation = gb_operation_create(connection, type,

					request_size, response_size);

	if (!operation)

		return -ENOMEM;



	if (request_size)

		memcpy(&operation->request->payload, request, request_size);



	/* Synchronous operation--no callback */

	ret = gb_operation_request_send(operation, NULL);

	if (ret)

		pr_err("version operation failed (%d)\n", ret);

	else

		if (response_size)

			memcpy(response, operation->response->payload,

			       response_size);

	gb_operation_destroy(operation);



	return ret;

}



int gb_operation_init(void)

{

	gb_operation_cache = kmem_cache_create("gb_operation_cache",

drivers/staging/greybus/operation.h

+4 −0
Original line number Diff line number Diff line
@@ -105,6 +105,10 @@ int gb_operation_status_map(u8 status); 
void greybus_data_sent(struct greybus_host_device *hd,

				void *header, int status);



int gb_operation_sync(struct gb_connection *connection, int type,

		      void *request, int request_size,

		      void *response, int response_size);



int gb_operation_init(void);

void gb_operation_exit(void);