96 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			96 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 OR MIT */
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| 
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| /*
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|  * Xen para-virtual sound device
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|  *
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|  * Copyright (C) 2016-2018 EPAM Systems Inc.
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|  *
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|  * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
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|  */
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| 
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| #ifndef __XEN_SND_FRONT_EVTCHNL_H
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| #define __XEN_SND_FRONT_EVTCHNL_H
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| 
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| #include <xen/interface/io/sndif.h>
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| 
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| struct xen_snd_front_info;
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| 
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| #ifndef GRANT_INVALID_REF
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| /*
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|  * FIXME: usage of grant reference 0 as invalid grant reference:
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|  * grant reference 0 is valid, but never exposed to a PV driver,
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|  * because of the fact it is already in use/reserved by the PV console.
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|  */
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| #define GRANT_INVALID_REF	0
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| #endif
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| 
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| /* Timeout in ms to wait for backend to respond. */
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| #define VSND_WAIT_BACK_MS	3000
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| 
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| enum xen_snd_front_evtchnl_state {
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| 	EVTCHNL_STATE_DISCONNECTED,
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| 	EVTCHNL_STATE_CONNECTED,
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| };
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| 
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| enum xen_snd_front_evtchnl_type {
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| 	EVTCHNL_TYPE_REQ,
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| 	EVTCHNL_TYPE_EVT,
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| };
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| 
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| struct xen_snd_front_evtchnl {
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| 	struct xen_snd_front_info *front_info;
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| 	int gref;
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| 	int port;
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| 	int irq;
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| 	int index;
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| 	/* State of the event channel. */
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| 	enum xen_snd_front_evtchnl_state state;
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| 	enum xen_snd_front_evtchnl_type type;
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| 	/* Either response id or incoming event id. */
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| 	u16 evt_id;
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| 	/* Next request id or next expected event id. */
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| 	u16 evt_next_id;
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| 	/* Shared ring access lock. */
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| 	struct mutex ring_io_lock;
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| 	union {
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| 		struct {
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| 			struct xen_sndif_front_ring ring;
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| 			struct completion completion;
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| 			/* Serializer for backend IO: request/response. */
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| 			struct mutex req_io_lock;
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| 
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| 			/* Latest response status. */
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| 			int resp_status;
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| 			union {
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| 				struct xensnd_query_hw_param hw_param;
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| 			} resp;
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| 		} req;
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| 		struct {
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| 			struct xensnd_event_page *page;
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| 			/* This is needed to handle XENSND_EVT_CUR_POS event. */
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| 			struct snd_pcm_substream *substream;
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| 		} evt;
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| 	} u;
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| };
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| 
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| struct xen_snd_front_evtchnl_pair {
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| 	struct xen_snd_front_evtchnl req;
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| 	struct xen_snd_front_evtchnl evt;
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| };
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| 
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| int xen_snd_front_evtchnl_create_all(struct xen_snd_front_info *front_info,
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| 				     int num_streams);
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| 
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| void xen_snd_front_evtchnl_free_all(struct xen_snd_front_info *front_info);
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| 
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| int xen_snd_front_evtchnl_publish_all(struct xen_snd_front_info *front_info);
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| 
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| void xen_snd_front_evtchnl_flush(struct xen_snd_front_evtchnl *evtchnl);
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| 
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| void xen_snd_front_evtchnl_pair_set_connected(struct xen_snd_front_evtchnl_pair *evt_pair,
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| 					      bool is_connected);
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| 
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| void xen_snd_front_evtchnl_pair_clear(struct xen_snd_front_evtchnl_pair *evt_pair);
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| 
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| #endif /* __XEN_SND_FRONT_EVTCHNL_H */
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