On 04/16/2018 05:09 PM, Juergen Gross wrote:One question still remains wrt alsa_* names: if this is for structures
On 16/04/18 08:24, Oleksandr Andrushchenko wrote:I'll try to do something about naming
From: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>Not sure how this is generally handled in the sound drivers, but when
Implement essential initialization of the sound driver:
ÂÂ - introduce required data structures
ÂÂ - handle driver registration
ÂÂ - handle sound card registration
ÂÂ - register sound driver on backend connection
ÂÂ - remove sound driver on backend disconnect
Initialize virtual sound card with streams according to the
Xen store configuration.
Implement ALSA driver operations including:
- manage frontend/backend shared buffers
- manage Xen bus event channel states
Implement requests from front to back for ALSA
PCM operations.
 - report ALSA period elapsed event: handle XENSND_EVT_CUR_POS
ÂÂÂ notifications from the backend when stream position advances
ÂÂÂ during playback/capture. The event carries a value of how
ÂÂÂ many octets were played/captured at the time of the event.
 - implement explicit stream parameter negotiation between
ÂÂÂ backend and frontend: handle XENSND_OP_HW_PARAM_QUERY request
ÂÂÂ to read/update configuration space for the parameter given:
ÂÂÂ request passes desired parameter interval and the response to
ÂÂÂ this request returns min/max interval for the parameter to be used.
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
---
 sound/xen/Makefile | 3 +-
 sound/xen/xen_snd_front.c | 193 ++++++++-
 sound/xen/xen_snd_front.h | 28 ++
 sound/xen/xen_snd_front_alsa.c | 830 ++++++++++++++++++++++++++++++++++++++
 sound/xen/xen_snd_front_alsa.h | 23 ++
 sound/xen/xen_snd_front_evtchnl.c | 6 +-
 6 files changed, 1080 insertions(+), 3 deletions(-)
 create mode 100644 sound/xen/xen_snd_front_alsa.c
 create mode 100644 sound/xen/xen_snd_front_alsa.h
diff --git a/sound/xen/Makefile b/sound/xen/Makefile
index f028bc30af5d..1e6470ecc2f2 100644
--- a/sound/xen/Makefile
+++ b/sound/xen/Makefile
@@ -3,6 +3,7 @@
 snd_xen_front-objs := xen_snd_front.o \
ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ xen_snd_front_cfg.o \
ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ xen_snd_front_evtchnl.o \
-ÂÂÂÂÂÂÂÂÂÂÂÂÂ xen_snd_front_shbuf.o
+ÂÂÂÂÂÂÂÂÂÂÂÂÂ xen_snd_front_shbuf.o \
+ÂÂÂÂÂÂÂÂÂÂÂÂÂ xen_snd_front_alsa.o
  obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
index 0569c6c596a3..1fef253ea21a 100644
--- a/sound/xen/xen_snd_front.c
+++ b/sound/xen/xen_snd_front.c
@@ -19,10 +19,201 @@
 #include <xen/interface/io/sndif.h>
  #include "xen_snd_front.h"
+#include "xen_snd_front_alsa.h"
 #include "xen_snd_front_evtchnl.h"
+#include "xen_snd_front_shbuf.h"
+
+static struct xensnd_req *
+be_stream_prepare_req(struct xen_snd_front_evtchnl *evtchnl, u8 operation)
+{
+ÂÂÂ struct xensnd_req *req;
+
+ÂÂÂ req = RING_GET_REQUEST(&evtchnl->u.req.ring,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ evtchnl->u.req.ring.req_prod_pvt);
+ÂÂÂ req->operation = operation;
+ÂÂÂ req->id = evtchnl->evt_next_id++;
+ÂÂÂ evtchnl->evt_id = req->id;
+ÂÂÂ return req;
+}
+
+static int be_stream_do_io(struct xen_snd_front_evtchnl *evtchnl)
+{
+ÂÂÂ if (unlikely(evtchnl->state != EVTCHNL_STATE_CONNECTED))
+ÂÂÂÂÂÂÂ return -EIO;
+
+ÂÂÂ reinit_completion(&evtchnl->u.req.completion);
+ÂÂÂ xen_snd_front_evtchnl_flush(evtchnl);
+ÂÂÂ return 0;
+}
+
+static int be_stream_wait_io(struct xen_snd_front_evtchnl *evtchnl)
+{
+ÂÂÂ if (wait_for_completion_timeout(&evtchnl->u.req.completion,
+ÂÂÂÂÂÂÂÂÂÂÂ msecs_to_jiffies(VSND_WAIT_BACK_MS)) <= 0)
+ÂÂÂÂÂÂÂ return -ETIMEDOUT;
+
+ÂÂÂ return evtchnl->u.req.resp_status;
+}
+
+int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct xensnd_query_hw_param *hw_param_req,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct xensnd_query_hw_param *hw_param_resp)
+{
+ÂÂÂ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ÂÂÂ struct xensnd_req *req;
+ÂÂÂ unsigned long flags;
+ÂÂÂ int ret;
+
+ÂÂÂ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ÂÂÂ spin_lock_irqsave(&front_info->io_lock, flags);
+ÂÂÂ req = be_stream_prepare_req(evtchnl, XENSND_OP_HW_PARAM_QUERY);
+ÂÂÂ req->op.hw_param = *hw_param_req;
+
+ÂÂÂ ret = be_stream_do_io(evtchnl);
+ÂÂÂ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ÂÂÂ if (ret == 0)
+ÂÂÂÂÂÂÂ ret = be_stream_wait_io(evtchnl);
+
+ÂÂÂ if (ret == 0)
+ÂÂÂÂÂÂÂ *hw_param_resp = evtchnl->u.req.resp.hw_param;
+
+ÂÂÂ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ÂÂÂ return ret;
+}
+
+int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct xen_snd_front_shbuf *sh_buf,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ u8 format, unsigned int channels,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned int rate, u32 buffer_sz,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ u32 period_sz)
+{
+ÂÂÂ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ÂÂÂ struct xensnd_req *req;
+ÂÂÂ unsigned long flags;
+ÂÂÂ int ret;
+
+ÂÂÂ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ÂÂÂ spin_lock_irqsave(&front_info->io_lock, flags);
+ÂÂÂ req = be_stream_prepare_req(evtchnl, XENSND_OP_OPEN);
+ÂÂÂ req->op.open.pcm_format = format;
+ÂÂÂ req->op.open.pcm_channels = channels;
+ÂÂÂ req->op.open.pcm_rate = rate;
+ÂÂÂ req->op.open.buffer_sz = buffer_sz;
+ÂÂÂ req->op.open.period_sz = period_sz;
+ÂÂÂ req->op.open.gref_directory = xen_snd_front_shbuf_get_dir_start(sh_buf);
+
+ÂÂÂ ret = be_stream_do_io(evtchnl);
+ÂÂÂ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ÂÂÂ if (ret == 0)
+ÂÂÂÂÂÂÂ ret = be_stream_wait_io(evtchnl);
+
+ÂÂÂ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ÂÂÂ return ret;
+}
+
+int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl)
+{
+ÂÂÂ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ÂÂÂ struct xensnd_req *req;
+ÂÂÂ unsigned long flags;
+ÂÂÂ int ret;
+
+ÂÂÂ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ÂÂÂ spin_lock_irqsave(&front_info->io_lock, flags);
+ÂÂÂ req = be_stream_prepare_req(evtchnl, XENSND_OP_CLOSE);
+
+ÂÂÂ ret = be_stream_do_io(evtchnl);
+ÂÂÂ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ÂÂÂ if (ret == 0)
+ÂÂÂÂÂÂÂ ret = be_stream_wait_io(evtchnl);
+
+ÂÂÂ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ÂÂÂ return ret;
+}
+
+int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long pos, unsigned long count)
+{
+ÂÂÂ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ÂÂÂ struct xensnd_req *req;
+ÂÂÂ unsigned long flags;
+ÂÂÂ int ret;
+
+ÂÂÂ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ÂÂÂ spin_lock_irqsave(&front_info->io_lock, flags);
+ÂÂÂ req = be_stream_prepare_req(evtchnl, XENSND_OP_WRITE);
+ÂÂÂ req->op.rw.length = count;
+ÂÂÂ req->op.rw.offset = pos;
+
+ÂÂÂ ret = be_stream_do_io(evtchnl);
+ÂÂÂ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ÂÂÂ if (ret == 0)
+ÂÂÂÂÂÂÂ ret = be_stream_wait_io(evtchnl);
+
+ÂÂÂ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ÂÂÂ return ret;
+}
+
+int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long pos, unsigned long count)
+{
+ÂÂÂ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ÂÂÂ struct xensnd_req *req;
+ÂÂÂ unsigned long flags;
+ÂÂÂ int ret;
+
+ÂÂÂ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ÂÂÂ spin_lock_irqsave(&front_info->io_lock, flags);
+ÂÂÂ req = be_stream_prepare_req(evtchnl, XENSND_OP_READ);
+ÂÂÂ req->op.rw.length = count;
+ÂÂÂ req->op.rw.offset = pos;
+
+ÂÂÂ ret = be_stream_do_io(evtchnl);
+ÂÂÂ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ÂÂÂ if (ret == 0)
+ÂÂÂÂÂÂÂ ret = be_stream_wait_io(evtchnl);
+
+ÂÂÂ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ÂÂÂ return ret;
+}
+
+int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int type)
+{
+ÂÂÂ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ÂÂÂ struct xensnd_req *req;
+ÂÂÂ unsigned long flags;
+ÂÂÂ int ret;
+
+ÂÂÂ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ÂÂÂ spin_lock_irqsave(&front_info->io_lock, flags);
+ÂÂÂ req = be_stream_prepare_req(evtchnl, XENSND_OP_TRIGGER);
+ÂÂÂ req->op.trigger.type = type;
+
+ÂÂÂ ret = be_stream_do_io(evtchnl);
+ÂÂÂ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ÂÂÂ if (ret == 0)
+ÂÂÂÂÂÂÂ ret = be_stream_wait_io(evtchnl);
+
+ÂÂÂ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ÂÂÂ return ret;
+}
  static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
 {
+ÂÂÂ xen_snd_front_alsa_fini(front_info);
ÂÂÂÂÂ xen_snd_front_evtchnl_free_all(front_info);
 }
 @@ -45,7 +236,7 @@ static int sndback_initwait(struct xen_snd_front_info *front_info)
  static int sndback_connect(struct xen_snd_front_info *front_info)
 {
-ÂÂÂ return 0;
+ÂÂÂ return xen_snd_front_alsa_init(front_info);
 }
  static void sndback_disconnect(struct xen_snd_front_info *front_info)
diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
index 9c2ffbb4e4b8..7adbdb4d2019 100644
--- a/sound/xen/xen_snd_front.h
+++ b/sound/xen/xen_snd_front.h
@@ -13,17 +13,45 @@
  #include "xen_snd_front_cfg.h"
 +struct card_info;
+struct xen_snd_front_evtchnl;
 struct xen_snd_front_evtchnl_pair;
+struct xen_snd_front_shbuf;
+struct xensnd_query_hw_param;
  struct xen_snd_front_info {
ÂÂÂÂÂ struct xenbus_device *xb_dev;
 + struct card_info *card_info;
+
ÂÂÂÂÂ /* serializer for backend IO: request/response */
ÂÂÂÂÂ spinlock_t io_lock;
+
ÂÂÂÂÂ int num_evt_pairs;
ÂÂÂÂÂ struct xen_snd_front_evtchnl_pair *evt_pairs;
 Â struct xen_front_cfg_card cfg;
 };
 +int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct xensnd_query_hw_param *hw_param_req,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct xensnd_query_hw_param *hw_param_resp);
+
+int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct xen_snd_front_shbuf *sh_buf,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ u8 format, unsigned int channels,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned int rate, u32 buffer_sz,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ u32 period_sz);
+
+int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl);
+
+int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long pos, unsigned long count);
+
+int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long pos, unsigned long count);
+
+int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int type);
+
 #endif /* __XEN_SND_FRONT_H */
diff --git a/sound/xen/xen_snd_front_alsa.c b/sound/xen/xen_snd_front_alsa.c
new file mode 100644
index 000000000000..f524b172750e
--- /dev/null
+++ b/sound/xen/xen_snd_front_alsa.c
@@ -0,0 +1,830 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
+ */
+
+#include <linux/platform_device.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#include <xen/xenbus.h>
+
+#include "xen_snd_front.h"
+#include "xen_snd_front_alsa.h"
+#include "xen_snd_front_cfg.h"
+#include "xen_snd_front_evtchnl.h"
+#include "xen_snd_front_shbuf.h"
+
+struct pcm_stream_info {
reviewing the code using those structures I repeatedly tried to find
their definitions in the sound headers instead of here. Same applies to
the alsa_* names.
I'd prefer names which don't poison the name space.
Well, this code has issues and will be re-worked:+ÂÂÂ struct xen_snd_front_info *front_info;Is this correct? Why can you free the lock here without doing any
+ÂÂÂ struct xen_snd_front_evtchnl_pair *evt_pair;
+ÂÂÂ struct xen_snd_front_shbuf sh_buf;
+ÂÂÂ int index;
+
+ÂÂÂ bool is_open;
+ÂÂÂ struct snd_pcm_hardware pcm_hw;
+
+ÂÂÂ /* number of processed frames as reported by the backend */
+ÂÂÂ snd_pcm_uframes_t be_cur_frame;
+ÂÂÂ /* current HW pointer to be reported via .period callback */
+ÂÂÂ atomic_t hw_ptr;
+ÂÂÂ /* modulo of the number of processed frames - for period detection */
+ÂÂÂ u32 out_frames;
+};
+
+struct pcm_instance_info {
+ÂÂÂ struct card_info *card_info;
+ÂÂÂ struct snd_pcm *pcm;
+ÂÂÂ struct snd_pcm_hardware pcm_hw;
+ÂÂÂ int num_pcm_streams_pb;
+ÂÂÂ struct pcm_stream_info *streams_pb;
+ÂÂÂ int num_pcm_streams_cap;
+ÂÂÂ struct pcm_stream_info *streams_cap;
+};
+
+struct card_info {
+ÂÂÂ struct xen_snd_front_info *front_info;
+ÂÂÂ struct snd_card *card;
+ÂÂÂ struct snd_pcm_hardware pcm_hw;
+ÂÂÂ int num_pcm_instances;
+ÂÂÂ struct pcm_instance_info *pcm_instances;
+};
+
+struct alsa_sndif_sample_format {
+ÂÂÂ u8 sndif;
+ÂÂÂ snd_pcm_format_t alsa;
+};
+
+struct alsa_sndif_hw_param {
+ÂÂÂ u8 sndif;
+ÂÂÂ snd_pcm_hw_param_t alsa;
+};
+
+static const struct alsa_sndif_sample_format ALSA_SNDIF_FORMATS[] = {
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_U8,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_U8
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_S8,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_S8
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_U16_LE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_U16_LE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_U16_BE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_U16_BE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_S16_LE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_S16_LE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_S16_BE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_S16_BE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_U24_LE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_U24_LE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_U24_BE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_U24_BE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_S24_LE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_S24_LE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_S24_BE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_S24_BE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_U32_LE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_U32_LE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_U32_BE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_U32_BE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_S32_LE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_S32_LE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_S32_BE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_S32_BE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_A_LAW,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_A_LAW
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_MU_LAW,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_MU_LAW
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_F32_LE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_FLOAT_LE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_F32_BE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_FLOAT_BE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_F64_LE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_FLOAT64_LE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_F64_BE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_FLOAT64_BE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_IMA_ADPCM,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_IMA_ADPCM
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_MPEG,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_MPEG
+ÂÂÂ },
+ÂÂÂ {
+ÂÂÂÂÂÂÂ .sndif = XENSND_PCM_FORMAT_GSM,
+ÂÂÂÂÂÂÂ .alsa = SNDRV_PCM_FORMAT_GSM
+ÂÂÂ },
+};
+
+static int to_sndif_format(snd_pcm_format_t format)
+{
+ÂÂÂ int i;
+
+ÂÂÂ for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
+ÂÂÂÂÂÂÂ if (ALSA_SNDIF_FORMATS[i].alsa == format)
+ÂÂÂÂÂÂÂÂÂÂÂ return ALSA_SNDIF_FORMATS[i].sndif;
+
+ÂÂÂ return -EINVAL;
+}
+
+static u64 to_sndif_formats_mask(u64 alsa_formats)
+{
+ÂÂÂ u64 mask;
+ÂÂÂ int i;
+
+ÂÂÂ mask = 0;
+ÂÂÂ for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
+ÂÂÂÂÂÂÂ if (1 << ALSA_SNDIF_FORMATS[i].alsa & alsa_formats)
+ÂÂÂÂÂÂÂÂÂÂÂ mask |= 1 << ALSA_SNDIF_FORMATS[i].sndif;
+
+ÂÂÂ return mask;
+}
+
+static u64 to_alsa_formats_mask(u64 sndif_formats)
+{
+ÂÂÂ u64 mask;
+ÂÂÂ int i;
+
+ÂÂÂ mask = 0;
+ÂÂÂ for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
+ÂÂÂÂÂÂÂ if (1 << ALSA_SNDIF_FORMATS[i].sndif & sndif_formats)
+ÂÂÂÂÂÂÂÂÂÂÂ mask |= 1 << ALSA_SNDIF_FORMATS[i].alsa;
+
+ÂÂÂ return mask;
+}
+
+static void stream_clear(struct pcm_stream_info *stream)
+{
+ÂÂÂ stream->is_open = false;
+ÂÂÂ stream->be_cur_frame = 0;
+ÂÂÂ stream->out_frames = 0;
+ÂÂÂ atomic_set(&stream->hw_ptr, 0);
+ÂÂÂ xen_snd_front_evtchnl_pair_clear(stream->evt_pair);
+ÂÂÂ xen_snd_front_shbuf_clear(&stream->sh_buf);
+}
+
+static void stream_free(struct pcm_stream_info *stream)
+{
+ÂÂÂ xen_snd_front_shbuf_free(&stream->sh_buf);
+ÂÂÂ stream_clear(stream);
+}
+
+static struct pcm_stream_info *stream_get(struct snd_pcm_substream *substream)
+{
+ÂÂÂ struct pcm_instance_info *pcm_instance =
+ÂÂÂÂÂÂÂÂÂÂÂ snd_pcm_substream_chip(substream);
+ÂÂÂ struct pcm_stream_info *stream;
+
+ÂÂÂ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+ÂÂÂÂÂÂÂ stream = &pcm_instance->streams_pb[substream->number];
+ÂÂÂ else
+ÂÂÂÂÂÂÂ stream = &pcm_instance->streams_cap[substream->number];
+
+ÂÂÂ return stream;
+}
+
+static int alsa_hw_rule(struct snd_pcm_hw_params *params,
+ÂÂÂÂÂÂÂÂÂÂÂ struct snd_pcm_hw_rule *rule)
+{
+ÂÂÂ struct pcm_stream_info *stream = rule->private;
+ÂÂÂ struct device *dev = &stream->front_info->xb_dev->dev;
+ÂÂÂ struct snd_mask *formats =
+ÂÂÂÂÂÂÂÂÂÂÂ hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
+ÂÂÂ struct snd_interval *rates =
+ÂÂÂÂÂÂÂÂÂÂÂ hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
+ÂÂÂ struct snd_interval *channels =
+ÂÂÂÂÂÂÂÂÂÂÂ hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
+ÂÂÂ struct snd_interval *period =
+ÂÂÂÂÂÂÂÂÂÂÂ hw_param_interval(params,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
+ÂÂÂ struct snd_interval *buffer =
+ÂÂÂÂÂÂÂÂÂÂÂ hw_param_interval(params,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_HW_PARAM_BUFFER_SIZE);
+ÂÂÂ struct xensnd_query_hw_param req;
+ÂÂÂ struct xensnd_query_hw_param resp;
+ÂÂÂ struct snd_interval interval;
+ÂÂÂ struct snd_mask mask;
+ÂÂÂ u64 sndif_formats;
+ÂÂÂ int changed, ret;
+
+ÂÂÂ /* collect all the values we need for the query */
+
+ÂÂÂ req.formats = to_sndif_formats_mask((u64)formats->bits[0] |
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ (u64)(formats->bits[1]) << 32);
+
+ÂÂÂ req.rates.min = rates->min;
+ÂÂÂ req.rates.max = rates->max;
+
+ÂÂÂ req.channels.min = channels->min;
+ÂÂÂ req.channels.max = channels->max;
+
+ÂÂÂ req.buffer.min = buffer->min;
+ÂÂÂ req.buffer.max = buffer->max;
+
+ÂÂÂ req.period.min = period->min;
+ÂÂÂ req.period.max = period->max;
+
+ÂÂÂ ret = xen_snd_front_stream_query_hw_param(&stream->evt_pair->req,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ &req, &resp);
+ÂÂÂ if (ret < 0) {
+ÂÂÂÂÂÂÂ /* check if this is due to backend communication error */
+ÂÂÂÂÂÂÂ if (ret == -EIO || ret == -ETIMEDOUT)
+ÂÂÂÂÂÂÂÂÂÂÂ dev_err(dev, "Failed to query ALSA HW parameters\n");
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ }
+
+ÂÂÂ /* refine HW parameters after the query */
+ changed = 0;
+
+ÂÂÂ sndif_formats = to_alsa_formats_mask(resp.formats);
+ÂÂÂ snd_mask_none(&mask);
+ÂÂÂ mask.bits[0] = (u32)sndif_formats;
+ÂÂÂ mask.bits[1] = (u32)(sndif_formats >> 32);
+ÂÂÂ ret = snd_mask_refine(formats, &mask);
+ÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ changed |= ret;
+
+ÂÂÂ interval.openmin = 0;
+ÂÂÂ interval.openmax = 0;
+ÂÂÂ interval.integer = 1;
+
+ÂÂÂ interval.min = resp.rates.min;
+ÂÂÂ interval.max = resp.rates.max;
+ÂÂÂ ret = snd_interval_refine(rates, &interval);
+ÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ changed |= ret;
+
+ÂÂÂ interval.min = resp.channels.min;
+ÂÂÂ interval.max = resp.channels.max;
+ÂÂÂ ret = snd_interval_refine(channels, &interval);
+ÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ changed |= ret;
+
+ÂÂÂ interval.min = resp.buffer.min;
+ÂÂÂ interval.max = resp.buffer.max;
+ÂÂÂ ret = snd_interval_refine(buffer, &interval);
+ÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ changed |= ret;
+
+ÂÂÂ interval.min = resp.period.min;
+ÂÂÂ interval.max = resp.period.max;
+ÂÂÂ ret = snd_interval_refine(period, &interval);
+ÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ changed |= ret;
+
+ÂÂÂ return changed;
+}
+
+static int alsa_open(struct snd_pcm_substream *substream)
+{
+ÂÂÂ struct pcm_instance_info *pcm_instance =
+ÂÂÂÂÂÂÂÂÂÂÂ snd_pcm_substream_chip(substream);
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+ÂÂÂ struct snd_pcm_runtime *runtime = substream->runtime;
+ÂÂÂ struct xen_snd_front_info *front_info =
+ÂÂÂÂÂÂÂÂÂÂÂ pcm_instance->card_info->front_info;
+ÂÂÂ struct device *dev = &front_info->xb_dev->dev;
+ÂÂÂ unsigned long flags;
+ÂÂÂ int ret;
+
+ÂÂÂ /*
+ÂÂÂÂ * return our HW properties: override defaults with those configured
+ÂÂÂÂ * via XenStore
+ÂÂÂÂ */
+ÂÂÂ runtime->hw = stream->pcm_hw;
+ÂÂÂ runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_INFO_MMAP_VALID |
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_INFO_DOUBLE |
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_INFO_BATCH |
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_INFO_NONINTERLEAVED |
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_INFO_RESUME |
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_INFO_PAUSE);
+ÂÂÂ runtime->hw.info |= SNDRV_PCM_INFO_INTERLEAVED;
+
+ÂÂÂ spin_lock_irqsave(&front_info->io_lock, flags);
+
+ÂÂÂ stream->evt_pair = &front_info->evt_pairs[stream->index];
+
+ÂÂÂ stream->front_info = front_info;
+
+ xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, true);
+
+ÂÂÂ stream->evt_pair->evt.u.evt.substream = substream;
+
+ÂÂÂ stream_clear(stream);
+
+ÂÂÂ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ÂÂÂ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ alsa_hw_rule, stream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_HW_PARAM_FORMAT, -1);
+ÂÂÂ if (ret) {
+ÂÂÂÂÂÂÂ dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_FORMAT\n");
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ }
+
+ÂÂÂ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ alsa_hw_rule, stream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_HW_PARAM_RATE, -1);
+ÂÂÂ if (ret) {
+ÂÂÂÂÂÂÂ dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_RATE\n");
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ }
+
+ÂÂÂ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ alsa_hw_rule, stream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_HW_PARAM_CHANNELS, -1);
+ÂÂÂ if (ret) {
+ÂÂÂÂÂÂÂ dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_CHANNELS\n");
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ }
+
+ÂÂÂ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ alsa_hw_rule, stream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
+ÂÂÂ if (ret) {
+ÂÂÂÂÂÂÂ dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_PERIOD_SIZE\n");
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ }
+
+ÂÂÂ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ alsa_hw_rule, stream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
+ÂÂÂ if (ret) {
+ÂÂÂÂÂÂÂ dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_BUFFER_SIZE\n");
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ }
+
+ÂÂÂ return 0;
+}
+
+static int alsa_close(struct snd_pcm_substream *substream)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+ÂÂÂ unsigned long flags;
+
+ÂÂÂ spin_lock_irqsave(&stream->front_info->io_lock, flags);
+
+ xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, false);
+
+ spin_unlock_irqrestore(&stream->front_info->io_lock, flags);
+ÂÂÂ return 0;
+}
+
+static int alsa_hw_params(struct snd_pcm_substream *substream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂ struct snd_pcm_hw_params *params)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+ÂÂÂ int ret;
+
+ÂÂÂ /*
+ÂÂÂÂ * this callback may be called multiple times,
+ÂÂÂÂ * so free the previously allocated shared buffer if any
+ÂÂÂÂ */
+ÂÂÂ stream_free(stream);
+
+ÂÂÂ ret = xen_snd_front_shbuf_alloc(stream->front_info->xb_dev,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ &stream->sh_buf,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ params_buffer_bytes(params));
+ÂÂÂ if (ret < 0) {
+ÂÂÂÂÂÂÂ stream_free(stream);
+ dev_err(&stream->front_info->xb_dev->dev,
+ÂÂÂÂÂÂÂÂÂÂÂ "Failed to allocate buffers for stream with index %d\n",
+ÂÂÂÂÂÂÂÂÂÂÂ stream->index);
+ÂÂÂÂÂÂÂ return ret;
+ÂÂÂ }
+
+ÂÂÂ return 0;
+}
+
+static int alsa_hw_free(struct snd_pcm_substream *substream)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+ÂÂÂ int ret;
+
+ÂÂÂ ret = xen_snd_front_stream_close(&stream->evt_pair->req);
+ÂÂÂ stream_free(stream);
+ÂÂÂ return ret;
+}
+
+static int alsa_prepare(struct snd_pcm_substream *substream)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+
+ÂÂÂ if (!stream->is_open) {
+ÂÂÂÂÂÂÂ struct snd_pcm_runtime *runtime = substream->runtime;
+ÂÂÂÂÂÂÂ u8 sndif_format;
+ÂÂÂÂÂÂÂ int ret;
+
+ÂÂÂÂÂÂÂ sndif_format = to_sndif_format(runtime->format);
+ÂÂÂÂÂÂÂ if (sndif_format < 0) {
+ dev_err(&stream->front_info->xb_dev->dev,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ "Unsupported sample format: %d\n",
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ runtime->format);
+ÂÂÂÂÂÂÂÂÂÂÂ return sndif_format;
+ÂÂÂÂÂÂÂ }
+
+ÂÂÂÂÂÂÂ ret = xen_snd_front_stream_prepare(&stream->evt_pair->req,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ &stream->sh_buf,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ sndif_format,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ runtime->channels,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ runtime->rate,
+ snd_pcm_lib_buffer_bytes(substream),
+ snd_pcm_lib_period_bytes(substream));
+ÂÂÂÂÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂÂÂÂÂ return ret;
+
+ÂÂÂÂÂÂÂ stream->is_open = true;
+ÂÂÂ }
+
+ÂÂÂ return 0;
+}
+
+static int alsa_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+ÂÂÂ int type;
+
+ÂÂÂ switch (cmd) {
+ÂÂÂ case SNDRV_PCM_TRIGGER_START:
+ÂÂÂÂÂÂÂ type = XENSND_OP_TRIGGER_START;
+ÂÂÂÂÂÂÂ break;
+
+ÂÂÂ case SNDRV_PCM_TRIGGER_RESUME:
+ÂÂÂÂÂÂÂ type = XENSND_OP_TRIGGER_RESUME;
+ÂÂÂÂÂÂÂ break;
+
+ÂÂÂ case SNDRV_PCM_TRIGGER_STOP:
+ÂÂÂÂÂÂÂ type = XENSND_OP_TRIGGER_STOP;
+ÂÂÂÂÂÂÂ break;
+
+ÂÂÂ case SNDRV_PCM_TRIGGER_SUSPEND:
+ÂÂÂÂÂÂÂ type = XENSND_OP_TRIGGER_PAUSE;
+ÂÂÂÂÂÂÂ break;
+
+ÂÂÂ default:
+ÂÂÂÂÂÂÂ return -EINVAL;
+ÂÂÂ }
+
+ÂÂÂ return xen_snd_front_stream_trigger(&stream->evt_pair->req, type);
+}
+
+void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ u64 pos_bytes)
+{
+ÂÂÂ struct snd_pcm_substream *substream = evtchnl->u.evt.substream;
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+ÂÂÂ snd_pcm_uframes_t delta, new_hw_ptr, cur_frame;
+
+ÂÂÂ cur_frame = bytes_to_frames(substream->runtime, pos_bytes);
+
+ÂÂÂ delta = cur_frame - stream->be_cur_frame;
+ÂÂÂ stream->be_cur_frame = cur_frame;
+
+ÂÂÂ new_hw_ptr = (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
+ÂÂÂ new_hw_ptr = (new_hw_ptr + delta) % substream->runtime->buffer_size;
+ÂÂÂ atomic_set(&stream->hw_ptr, (int)new_hw_ptr);
+
+ÂÂÂ stream->out_frames += delta;
+ÂÂÂ if (stream->out_frames > substream->runtime->period_size) {
+ÂÂÂÂÂÂÂ stream->out_frames %= substream->runtime->period_size;
+ÂÂÂÂÂÂÂ snd_pcm_period_elapsed(substream);
+ÂÂÂ }
+}
+
+static snd_pcm_uframes_t alsa_pointer(struct snd_pcm_substream *substream)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+
+ÂÂÂ return (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
+}
+
+static int alsa_pb_copy_user(struct snd_pcm_substream *substream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int channel, unsigned long pos, void __user *src,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long count)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+
+ÂÂÂ if (unlikely(pos + count > stream->sh_buf.buffer_sz))
+ÂÂÂÂÂÂÂ return -EINVAL;
+
+ÂÂÂ if (copy_from_user(stream->sh_buf.buffer + pos, src, count))
+ÂÂÂÂÂÂÂ return -EFAULT;
+
+ÂÂÂ return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
+}
+
+static int alsa_pb_copy_kernel(struct snd_pcm_substream *substream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int channel, unsigned long pos, void *src,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long count)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+
+ÂÂÂ if (unlikely(pos + count > stream->sh_buf.buffer_sz))
+ÂÂÂÂÂÂÂ return -EINVAL;
+
+ÂÂÂ memcpy(stream->sh_buf.buffer + pos, src, count);
+
+ÂÂÂ return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
+}
+
+static int alsa_cap_copy_user(struct snd_pcm_substream *substream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int channel, unsigned long pos, void __user *dst,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long count)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+ÂÂÂ int ret;
+
+ÂÂÂ if (unlikely(pos + count > stream->sh_buf.buffer_sz))
+ÂÂÂÂÂÂÂ return -EINVAL;
+
+ÂÂÂ ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
+ÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂ return ret;
+
+ÂÂÂ return copy_to_user(dst, stream->sh_buf.buffer + pos, count) ?
+ÂÂÂÂÂÂÂ -EFAULT : 0;
+}
+
+static int alsa_cap_copy_kernel(struct snd_pcm_substream *substream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int channel, unsigned long pos, void *dst,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long count)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+ÂÂÂ int ret;
+
+ÂÂÂ if (unlikely(pos + count > stream->sh_buf.buffer_sz))
+ÂÂÂÂÂÂÂ return -EINVAL;
+
+ÂÂÂ ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
+ÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂ return ret;
+
+ÂÂÂ memcpy(dst, stream->sh_buf.buffer + pos, count);
+
+ÂÂÂ return 0;
+}
+
+static int alsa_pb_fill_silence(struct snd_pcm_substream *substream,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ int channel, unsigned long pos,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long count)
+{
+ÂÂÂ struct pcm_stream_info *stream = stream_get(substream);
+
+ÂÂÂ if (unlikely(pos + count > stream->sh_buf.buffer_sz))
+ÂÂÂÂÂÂÂ return -EINVAL;
+
+ÂÂÂ memset(stream->sh_buf.buffer + pos, 0, count);
+
+ÂÂÂ return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
+}
+
+/*
+ * FIXME: The mmaped data transfer is asynchronous and there is no
+ * ack signal from user-space when it is done. This is the
+ * reason it is not implemented in the PV driver as we do need
+ * to know when the buffer can be transferred to the backend.
+ */
+
+static struct snd_pcm_ops snd_drv_alsa_playback_ops = {
+ÂÂÂ .open = alsa_open,
+ÂÂÂ .close = alsa_close,
+ÂÂÂ .ioctl = snd_pcm_lib_ioctl,
+ÂÂÂ .hw_params = alsa_hw_params,
+ÂÂÂ .hw_free = alsa_hw_free,
+ÂÂÂ .prepare = alsa_prepare,
+ÂÂÂ .trigger = alsa_trigger,
+ÂÂÂ .pointer = alsa_pointer,
+ÂÂÂ .copy_user = alsa_pb_copy_user,
+ÂÂÂ .copy_kernel = alsa_pb_copy_kernel,
+ÂÂÂ .fill_silence = alsa_pb_fill_silence,
+};
+
+static struct snd_pcm_ops snd_drv_alsa_capture_ops = {
+ÂÂÂ .open = alsa_open,
+ÂÂÂ .close = alsa_close,
+ÂÂÂ .ioctl = snd_pcm_lib_ioctl,
+ÂÂÂ .hw_params = alsa_hw_params,
+ÂÂÂ .hw_free = alsa_hw_free,
+ÂÂÂ .prepare = alsa_prepare,
+ÂÂÂ .trigger = alsa_trigger,
+ÂÂÂ .pointer = alsa_pointer,
+ÂÂÂ .copy_user = alsa_cap_copy_user,
+ÂÂÂ .copy_kernel = alsa_cap_copy_kernel,
+};
+
+static int new_pcm_instance(struct card_info *card_info,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct xen_front_cfg_pcm_instance *instance_cfg,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct pcm_instance_info *pcm_instance_info)
+{
+ÂÂÂ struct snd_pcm *pcm;
+ÂÂÂ int ret, i;
+
+ÂÂÂ dev_dbg(&card_info->front_info->xb_dev->dev,
+ÂÂÂÂÂÂÂ "New PCM device \"%s\" with id %d playback %d capture %d",
+ÂÂÂÂÂÂÂ instance_cfg->name,
+ÂÂÂÂÂÂÂ instance_cfg->device_id,
+ÂÂÂÂÂÂÂ instance_cfg->num_streams_pb,
+ÂÂÂÂÂÂÂ instance_cfg->num_streams_cap);
+
+ÂÂÂ pcm_instance_info->card_info = card_info;
+
+ÂÂÂ pcm_instance_info->pcm_hw = instance_cfg->pcm_hw;
+
+ÂÂÂ if (instance_cfg->num_streams_pb) {
+ÂÂÂÂÂÂÂ pcm_instance_info->streams_pb =
+ devm_kcalloc(&card_info->card->card_dev,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->num_streams_pb,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ sizeof(struct pcm_stream_info),
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ GFP_KERNEL);
+ÂÂÂÂÂÂÂ if (!pcm_instance_info->streams_pb)
+ÂÂÂÂÂÂÂÂÂÂÂ return -ENOMEM;
+ÂÂÂ }
+
+ÂÂÂ if (instance_cfg->num_streams_cap) {
+ÂÂÂÂÂÂÂ pcm_instance_info->streams_cap =
+ devm_kcalloc(&card_info->card->card_dev,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->num_streams_cap,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ sizeof(struct pcm_stream_info),
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ GFP_KERNEL);
+ÂÂÂÂÂÂÂ if (!pcm_instance_info->streams_cap)
+ÂÂÂÂÂÂÂÂÂÂÂ return -ENOMEM;
+ÂÂÂ }
+
+ÂÂÂ pcm_instance_info->num_pcm_streams_pb =
+ÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->num_streams_pb;
+ÂÂÂ pcm_instance_info->num_pcm_streams_cap =
+ÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->num_streams_cap;
+
+ÂÂÂ for (i = 0; i < pcm_instance_info->num_pcm_streams_pb; i++) {
+ÂÂÂÂÂÂÂ pcm_instance_info->streams_pb[i].pcm_hw =
+ÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->streams_pb[i].pcm_hw;
+ÂÂÂÂÂÂÂ pcm_instance_info->streams_pb[i].index =
+ÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->streams_pb[i].index;
+ÂÂÂ }
+
+ÂÂÂ for (i = 0; i < pcm_instance_info->num_pcm_streams_cap; i++) {
+ÂÂÂÂÂÂÂ pcm_instance_info->streams_cap[i].pcm_hw =
+ÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->streams_cap[i].pcm_hw;
+ÂÂÂÂÂÂÂ pcm_instance_info->streams_cap[i].index =
+ÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->streams_cap[i].index;
+ÂÂÂ }
+
+ÂÂÂ ret = snd_pcm_new(card_info->card, instance_cfg->name,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->device_id,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->num_streams_pb,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂ instance_cfg->num_streams_cap,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂ &pcm);
+ÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂ return ret;
+
+ÂÂÂ pcm->private_data = pcm_instance_info;
+ÂÂÂ pcm->info_flags = 0;
+ÂÂÂ /* we want to handle all PCM operations in non-atomic context */
+ÂÂÂ pcm->nonatomic = true;
+ÂÂÂ strncpy(pcm->name, "Virtual card PCM", sizeof(pcm->name));
+
+ÂÂÂ if (instance_cfg->num_streams_pb)
+ÂÂÂÂÂÂÂ snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ &snd_drv_alsa_playback_ops);
+
+ÂÂÂ if (instance_cfg->num_streams_cap)
+ÂÂÂÂÂÂÂ snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ &snd_drv_alsa_capture_ops);
+
+ÂÂÂ pcm_instance_info->pcm = pcm;
+ÂÂÂ return 0;
+}
+
+int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info)
+{
+ÂÂÂ struct device *dev = &front_info->xb_dev->dev;
+ÂÂÂ struct xen_front_cfg_card *cfg = &front_info->cfg;
+ÂÂÂ struct card_info *card_info;
+ÂÂÂ struct snd_card *card;
+ÂÂÂ int ret, i;
+
+ÂÂÂ dev_dbg(dev, "Creating virtual sound card\n");
+
+ÂÂÂ ret = snd_card_new(dev, 0, XENSND_DRIVER_NAME, THIS_MODULE,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂ sizeof(struct card_info), &card);
+ÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂ return ret;
+
+ÂÂÂ card_info = card->private_data;
+ÂÂÂ card_info->front_info = front_info;
+ÂÂÂ front_info->card_info = card_info;
+ÂÂÂ card_info->card = card;
+ÂÂÂ card_info->pcm_instances =
+ÂÂÂÂÂÂÂÂÂÂÂ devm_kcalloc(dev, cfg->num_pcm_instances,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ sizeof(struct pcm_instance_info),
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ GFP_KERNEL);
+ÂÂÂ if (!card_info->pcm_instances) {
+ÂÂÂÂÂÂÂ ret = -ENOMEM;
+ÂÂÂÂÂÂÂ goto fail;
+ÂÂÂ }
+
+ÂÂÂ card_info->num_pcm_instances = cfg->num_pcm_instances;
+ÂÂÂ card_info->pcm_hw = cfg->pcm_hw;
+
+ÂÂÂ for (i = 0; i < cfg->num_pcm_instances; i++) {
+ÂÂÂÂÂÂÂ ret = new_pcm_instance(card_info, &cfg->pcm_instances[i],
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ &card_info->pcm_instances[i]);
+ÂÂÂÂÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂÂÂÂÂ goto fail;
+ÂÂÂ }
+
+ÂÂÂ strncpy(card->driver, XENSND_DRIVER_NAME, sizeof(card->driver));
+ÂÂÂ strncpy(card->shortname, cfg->name_short, sizeof(card->shortname));
+ÂÂÂ strncpy(card->longname, cfg->name_long, sizeof(card->longname));
+
+ÂÂÂ ret = snd_card_register(card);
+ÂÂÂ if (ret < 0)
+ÂÂÂÂÂÂÂ goto fail;
+
+ÂÂÂ return 0;
+
+fail:
+ÂÂÂ snd_card_free(card);
+ÂÂÂ return ret;
+}
+
+void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info)
+{
+ÂÂÂ struct card_info *card_info;
+ÂÂÂ struct snd_card *card;
+
+ÂÂÂ card_info = front_info->card_info;
+ÂÂÂ if (!card_info)
+ÂÂÂÂÂÂÂ return;
+
+ÂÂÂ card = card_info->card;
+ÂÂÂ if (!card)
+ÂÂÂÂÂÂÂ return;
+
+ÂÂÂ dev_dbg(&front_info->xb_dev->dev, "Removing virtual sound card %d\n",
+ÂÂÂÂÂÂÂ card->number);
+ÂÂÂ snd_card_free(card);
+
+ÂÂÂ /* card_info will be freed when destroying front_info->xb_dev->dev */
+ÂÂÂ card_info->card = NULL;
+}
diff --git a/sound/xen/xen_snd_front_alsa.h b/sound/xen/xen_snd_front_alsa.h
new file mode 100644
index 000000000000..18abd9eec967
--- /dev/null
+++ b/sound/xen/xen_snd_front_alsa.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
+ */
+
+#ifndef __XEN_SND_FRONT_ALSA_H
+#define __XEN_SND_FRONT_ALSA_H
+
+struct xen_snd_front_info;
+
+int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info);
+
+void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info);
+
+void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ u64 pos_bytes);
+
+#endif /* __XEN_SND_FRONT_ALSA_H */
diff --git a/sound/xen/xen_snd_front_evtchnl.c b/sound/xen/xen_snd_front_evtchnl.c
index 9ece39f938f8..470196518716 100644
--- a/sound/xen/xen_snd_front_evtchnl.c
+++ b/sound/xen/xen_snd_front_evtchnl.c
@@ -14,6 +14,7 @@
 #include <xen/xenbus.h>
  #include "xen_snd_front.h"
+#include "xen_snd_front_alsa.h"
 #include "xen_snd_front_cfg.h"
 #include "xen_snd_front_evtchnl.h"
 @@ -111,7 +112,10 @@ static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
 Â switch (event->type) {
ÂÂÂÂÂÂÂÂÂ case XENSND_EVT_CUR_POS:
-ÂÂÂÂÂÂÂÂÂÂÂ /* do nothing at the moment */
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+ÂÂÂÂÂÂÂÂÂÂÂ xen_snd_front_alsa_handle_cur_pos(channel,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ event->op.cur_pos.position);
+ÂÂÂÂÂÂÂÂÂÂÂ spin_lock_irqsave(&front_info->io_lock, flags);
harm? What is the lock protecting? I'd like to see at least some
comments explaining why the lock is needed and why it can be dropped
here.
1. Which locks I need:
1.1. lock to serialize requests to backend
1.2. lock to protect the ring: between requests code and interrupt handler
2. I don't really need a spinlock here b/c interrupts are threaded,
so I can safely use a mutex: thus no need for fancy code with unlocking
and locking again while servicing xen_snd_front_alsa_handle_cur_pos
Thank you
Juergen