u-boot/include/mailbox-uclass.h
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

83 lines
2.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (c) 2016, NVIDIA CORPORATION.
*/
#ifndef _MAILBOX_UCLASS_H
#define _MAILBOX_UCLASS_H
/* See mailbox.h for background documentation. */
#include <mailbox.h>
struct udevice;
/**
* struct mbox_ops - The functions that a mailbox driver must implement.
*/
struct mbox_ops {
/**
* of_xlate - Translate a client's device-tree (OF) mailbox specifier.
*
* The mailbox core calls this function as the first step in
* implementing a client's mbox_get_by_*() call.
*
* If this function pointer is set to NULL, the mailbox core will use
* a default implementation, which assumes #mbox-cells = <1>, and that
* the DT cell contains a simple integer channel ID.
*
* At present, the mailbox API solely supports device-tree. If this
* changes, other xxx_xlate() functions may be added to support those
* other mechanisms.
*
* @chan: The channel to hold the translation result.
* @args: The mailbox specifier values from device tree.
* @return 0 if OK, or a negative error code.
*/
int (*of_xlate)(struct mbox_chan *chan,
struct ofnode_phandle_args *args);
/**
* request - Request a translated channel.
*
* The mailbox core calls this function as the second step in
* implementing a client's mbox_get_by_*() call, following a successful
* xxx_xlate() call.
*
* @chan: The channel to request; this has been filled in by a
* previoux xxx_xlate() function call.
* @return 0 if OK, or a negative error code.
*/
int (*request)(struct mbox_chan *chan);
/**
* free - Free a previously requested channel.
*
* This is the implementation of the client mbox_free() API.
*
* @chan: The channel to free.
* @return 0 if OK, or a negative error code.
*/
int (*free)(struct mbox_chan *chan);
/**
* send - Send a message over a mailbox channel
*
* @chan: The channel to send to the message to.
* @data: A pointer to the message to send.
* @return 0 if OK, or a negative error code.
*/
int (*send)(struct mbox_chan *chan, const void *data);
/**
* recv - Receive any available message from the channel.
*
* This function does not block. If not message is immediately
* available, the function should return an error.
*
* @chan: The channel to receive to the message from.
* @data: A pointer to the buffer to hold the received message.
* @return 0 if OK, -ENODATA if no message was available, or a negative
* error code.
*/
int (*recv)(struct mbox_chan *chan, void *data);
};
#endif