xref: /linux/sound/virtio/virtio_ctl_msg.h (revision 8be98d2f2a0a262f8bf8a0bc1fdf522b3c7aab17)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * virtio-snd: Virtio sound device
4  * Copyright (C) 2021 OpenSynergy GmbH
5  */
6 #ifndef VIRTIO_SND_MSG_H
7 #define VIRTIO_SND_MSG_H
8 
9 #include <linux/atomic.h>
10 #include <linux/virtio.h>
11 
12 struct virtio_snd;
13 struct virtio_snd_msg;
14 
15 void virtsnd_ctl_msg_ref(struct virtio_snd_msg *msg);
16 
17 void virtsnd_ctl_msg_unref(struct virtio_snd_msg *msg);
18 
19 void *virtsnd_ctl_msg_request(struct virtio_snd_msg *msg);
20 
21 void *virtsnd_ctl_msg_response(struct virtio_snd_msg *msg);
22 
23 struct virtio_snd_msg *virtsnd_ctl_msg_alloc(size_t request_size,
24 					     size_t response_size, gfp_t gfp);
25 
26 int virtsnd_ctl_msg_send(struct virtio_snd *snd, struct virtio_snd_msg *msg,
27 			 struct scatterlist *out_sgs,
28 			 struct scatterlist *in_sgs, bool nowait);
29 
30 /**
31  * virtsnd_ctl_msg_send_sync() - Simplified sending of synchronous message.
32  * @snd: VirtIO sound device.
33  * @msg: Control message.
34  *
35  * After returning from this function, the message will be deleted. If message
36  * content is still needed, the caller must additionally to
37  * virtsnd_ctl_msg_ref/unref() it.
38  *
39  * The msg_timeout_ms module parameter defines the message completion timeout.
40  * If the message is not completed within this time, the function will return an
41  * error.
42  *
43  * Context: Any context that permits to sleep.
44  * Return: 0 on success, -errno on failure.
45  *
46  * The return value is a message status code (VIRTIO_SND_S_XXX) converted to an
47  * appropriate -errno value.
48  */
virtsnd_ctl_msg_send_sync(struct virtio_snd * snd,struct virtio_snd_msg * msg)49 static inline int virtsnd_ctl_msg_send_sync(struct virtio_snd *snd,
50 					    struct virtio_snd_msg *msg)
51 {
52 	return virtsnd_ctl_msg_send(snd, msg, NULL, NULL, false);
53 }
54 
55 /**
56  * virtsnd_ctl_msg_send_async() - Simplified sending of asynchronous message.
57  * @snd: VirtIO sound device.
58  * @msg: Control message.
59  *
60  * Context: Any context.
61  * Return: 0 on success, -errno on failure.
62  */
virtsnd_ctl_msg_send_async(struct virtio_snd * snd,struct virtio_snd_msg * msg)63 static inline int virtsnd_ctl_msg_send_async(struct virtio_snd *snd,
64 					     struct virtio_snd_msg *msg)
65 {
66 	return virtsnd_ctl_msg_send(snd, msg, NULL, NULL, true);
67 }
68 
69 void virtsnd_ctl_msg_cancel_all(struct virtio_snd *snd);
70 
71 void virtsnd_ctl_msg_complete(struct virtio_snd_msg *msg);
72 
73 int virtsnd_ctl_query_info(struct virtio_snd *snd, int command, int start_id,
74 			   int count, size_t size, void *info);
75 
76 void virtsnd_ctl_notify_cb(struct virtqueue *vqueue);
77 
78 #endif /* VIRTIO_SND_MSG_H */
79