From 788ef64a2caee38cc4b8890abd3d7e54dfa3bcc9 Mon Sep 17 00:00:00 2001 From: Oleksandr Andrushchenko Date: Mon, 14 May 2018 09:27:39 +0300 Subject: ALSA: xen-front: Implement Xen event channel handling Handle Xen event channels: - create for all configured streams and publish corresponding ring references and event channels in Xen store, so backend can connect - implement event channels interrupt handlers - create and destroy event channels with respect to Xen bus state Signed-off-by: Oleksandr Andrushchenko Signed-off-by: Takashi Iwai --- sound/xen/xen_snd_front_evtchnl.h | 95 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) create mode 100644 sound/xen/xen_snd_front_evtchnl.h (limited to 'sound/xen/xen_snd_front_evtchnl.h') diff --git a/sound/xen/xen_snd_front_evtchnl.h b/sound/xen/xen_snd_front_evtchnl.h new file mode 100644 index 000000000000..cbe51fd1ec15 --- /dev/null +++ b/sound/xen/xen_snd_front_evtchnl.h @@ -0,0 +1,95 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ + +/* + * Xen para-virtual sound device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko + */ + +#ifndef __XEN_SND_FRONT_EVTCHNL_H +#define __XEN_SND_FRONT_EVTCHNL_H + +#include + +struct xen_snd_front_info; + +#ifndef GRANT_INVALID_REF +/* + * FIXME: usage of grant reference 0 as invalid grant reference: + * grant reference 0 is valid, but never exposed to a PV driver, + * because of the fact it is already in use/reserved by the PV console. + */ +#define GRANT_INVALID_REF 0 +#endif + +/* Timeout in ms to wait for backend to respond. */ +#define VSND_WAIT_BACK_MS 3000 + +enum xen_snd_front_evtchnl_state { + EVTCHNL_STATE_DISCONNECTED, + EVTCHNL_STATE_CONNECTED, +}; + +enum xen_snd_front_evtchnl_type { + EVTCHNL_TYPE_REQ, + EVTCHNL_TYPE_EVT, +}; + +struct xen_snd_front_evtchnl { + struct xen_snd_front_info *front_info; + int gref; + int port; + int irq; + int index; + /* State of the event channel. */ + enum xen_snd_front_evtchnl_state state; + enum xen_snd_front_evtchnl_type type; + /* Either response id or incoming event id. */ + u16 evt_id; + /* Next request id or next expected event id. */ + u16 evt_next_id; + /* Shared ring access lock. */ + struct mutex ring_io_lock; + union { + struct { + struct xen_sndif_front_ring ring; + struct completion completion; + /* Serializer for backend IO: request/response. */ + struct mutex req_io_lock; + + /* Latest response status. */ + int resp_status; + union { + struct xensnd_query_hw_param hw_param; + } resp; + } req; + struct { + struct xensnd_event_page *page; + /* This is needed to handle XENSND_EVT_CUR_POS event. */ + struct snd_pcm_substream *substream; + } evt; + } u; +}; + +struct xen_snd_front_evtchnl_pair { + struct xen_snd_front_evtchnl req; + struct xen_snd_front_evtchnl evt; +}; + +int xen_snd_front_evtchnl_create_all(struct xen_snd_front_info *front_info, + int num_streams); + +void xen_snd_front_evtchnl_free_all(struct xen_snd_front_info *front_info); + +int xen_snd_front_evtchnl_publish_all(struct xen_snd_front_info *front_info); + +void xen_snd_front_evtchnl_flush(struct xen_snd_front_evtchnl *evtchnl); + +void xen_snd_front_evtchnl_pair_set_connected(struct xen_snd_front_evtchnl_pair *evt_pair, + bool is_connected); + +void xen_snd_front_evtchnl_pair_clear(struct xen_snd_front_evtchnl_pair *evt_pair); + +#endif /* __XEN_SND_FRONT_EVTCHNL_H */ -- cgit v1.2.3