[PATCH RESEND 03/11] ALSA: vsnd: Read sound driver configuration from Xen store

Oleksandr Andrushchenko
2017-08-07T11:51:00Z

Read configuration values from Xen store according
to xen/interface/io/sndif.h protocol:
- introduce configuration structures for different
components, e.g. sound card, device, stream
- read PCM HW parameters, e.g rate, format etc.
- detect stream type (capture/playback)
- read device and card parameters

Fill in platform data with the configuration read, so
it can be passed to sound driver later.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
---
sound/drivers/xen-front.c | 530 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 530 insertions(+)

diff --git a/sound/drivers/xen-front.c b/sound/drivers/xen-front.c
index c4fd21cac3a7..ef48cbf44cf2 100644
--- a/sound/drivers/xen-front.c
+++ b/sound/drivers/xen-front.c
@@ -20,24 +20,554 @@

#include <linux/module.h>

+#include <sound/core.h>
+#include <sound/pcm.h>
+
#include <xen/platform_pci.h>
#include <xen/xen.h>
#include <xen/xenbus.h>

#include <xen/interface/io/sndif.h>

+/* maximum number of supported streams */
+#define VSND_MAX_STREAM 8
+
+struct cfg_stream {
+ int unique_id;
+ char *xenstore_path;
+ struct snd_pcm_hardware pcm_hw;
+};
+
+struct cfg_pcm_instance {
+ char name[80];
+ int device_id;
+ struct snd_pcm_hardware pcm_hw;
+ int num_streams_pb;
+ struct cfg_stream *streams_pb;
+ int num_streams_cap;
+ struct cfg_stream *streams_cap;
+};
+
+struct cfg_card {
+ char name_short[32];
+ char name_long[80];
+ struct snd_pcm_hardware pcm_hw;
+ int num_pcm_instances;
+ struct cfg_pcm_instance *pcm_instances;
+};
+
+struct sdev_card_plat_data {
+ struct xdrv_info *xdrv_info;
+ struct cfg_card cfg_card;
+};
+
struct xdrv_info {
struct xenbus_device *xb_dev;
spinlock_t io_lock;
struct mutex mutex;
+ struct sdev_card_plat_data cfg_plat_data;
};

+#define MAX_XEN_BUFFER_SIZE (64 * 1024)
+#define MAX_BUFFER_SIZE MAX_XEN_BUFFER_SIZE
+#define MIN_PERIOD_SIZE 64
+#define MAX_PERIOD_SIZE (MAX_BUFFER_SIZE / 8)
+#define USE_FORMATS (SNDRV_PCM_FMTBIT_U8 | \
+ SNDRV_PCM_FMTBIT_S16_LE)
+#define USE_RATE (SNDRV_PCM_RATE_CONTINUOUS | \
+ SNDRV_PCM_RATE_8000_48000)
+#define USE_RATE_MIN 5512
+#define USE_RATE_MAX 48000
+#define USE_CHANNELS_MIN 1
+#define USE_CHANNELS_MAX 2
+#define USE_PERIODS_MIN 2
+#define USE_PERIODS_MAX 8
+
+static struct snd_pcm_hardware sdrv_pcm_hw_default = {
+ .info = (SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_INTERLEAVED |
+ SNDRV_PCM_INFO_RESUME |
+ SNDRV_PCM_INFO_MMAP_VALID),
+ .formats = USE_FORMATS,
+ .rates = USE_RATE,
+ .rate_min = USE_RATE_MIN,
+ .rate_max = USE_RATE_MAX,
+ .channels_min = USE_CHANNELS_MIN,
+ .channels_max = USE_CHANNELS_MAX,
+ .buffer_bytes_max = MAX_BUFFER_SIZE,
+ .period_bytes_min = MIN_PERIOD_SIZE,
+ .period_bytes_max = MAX_PERIOD_SIZE,
+ .periods_min = USE_PERIODS_MIN,
+ .periods_max = USE_PERIODS_MAX,
+ .fifo_size = 0,
+};
+
+struct CFG_HW_SAMPLE_RATE {
+ const char *name;
+ unsigned int mask;
+ unsigned int value;
+};
+
+static struct CFG_HW_SAMPLE_RATE cfg_hw_supported_rates[] = {
+ { .name = "5512", .mask = SNDRV_PCM_RATE_5512, .value = 5512 },
+ { .name = "8000", .mask = SNDRV_PCM_RATE_8000, .value = 8000 },
+ { .name = "11025", .mask = SNDRV_PCM_RATE_11025, .value = 11025 },
+ { .name = "16000", .mask = SNDRV_PCM_RATE_16000, .value = 16000 },
+ { .name = "22050", .mask = SNDRV_PCM_RATE_22050, .value = 22050 },
+ { .name = "32000", .mask = SNDRV_PCM_RATE_32000, .value = 32000 },
+ { .name = "44100", .mask = SNDRV_PCM_RATE_44100, .value = 44100 },
+ { .name = "48000", .mask = SNDRV_PCM_RATE_48000, .value = 48000 },
+ { .name = "64000", .mask = SNDRV_PCM_RATE_64000, .value = 64000 },
+ { .name = "96000", .mask = SNDRV_PCM_RATE_96000, .value = 96000 },
+ { .name = "176400", .mask = SNDRV_PCM_RATE_176400, .value = 176400 },
+ { .name = "192000", .mask = SNDRV_PCM_RATE_192000, .value = 192000 },
+};
+
+struct CFG_HW_SAMPLE_FORMAT {
+ const char *name;
+ u64 mask;
+};
+
+static struct CFG_HW_SAMPLE_FORMAT cfg_hw_supported_formats[] = {
+ {
+ .name = XENSND_PCM_FORMAT_U8_STR,
+ .mask = SNDRV_PCM_FMTBIT_U8
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S8_STR,
+ .mask = SNDRV_PCM_FMTBIT_S8
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U16_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U16_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U16_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U16_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S16_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S16_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S16_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S16_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U24_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U24_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U24_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U24_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S24_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S24_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S24_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S24_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U32_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U32_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U32_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U32_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S32_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S32_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S32_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S32_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_A_LAW_STR,
+ .mask = SNDRV_PCM_FMTBIT_A_LAW
+ },
+ {
+ .name = XENSND_PCM_FORMAT_MU_LAW_STR,
+ .mask = SNDRV_PCM_FMTBIT_MU_LAW
+ },
+ {
+ .name = XENSND_PCM_FORMAT_F32_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_FLOAT_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_F32_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_FLOAT_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_F64_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_FLOAT64_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_F64_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_FLOAT64_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_IMA_ADPCM_STR,
+ .mask = SNDRV_PCM_FMTBIT_IMA_ADPCM
+ },
+ {
+ .name = XENSND_PCM_FORMAT_MPEG_STR,
+ .mask = SNDRV_PCM_FMTBIT_MPEG
+ },
+ {
+ .name = XENSND_PCM_FORMAT_GSM_STR,
+ .mask = SNDRV_PCM_FMTBIT_GSM
+ },
+};
+
+static void cfg_hw_rates(char *list, unsigned int len,
+ const char *path, struct snd_pcm_hardware *pcm_hw)
+{
+ char *cur_rate;
+ unsigned int cur_mask;
+ unsigned int cur_value;
+ unsigned int rates;
+ unsigned int rate_min;
+ unsigned int rate_max;
+ int i;
+
+ rates = 0;
+ rate_min = -1;
+ rate_max = 0;
+ while ((cur_rate = strsep(&list, XENSND_LIST_SEPARATOR))) {
+ for (i = 0; i < ARRAY_SIZE(cfg_hw_supported_rates); i++)
+ if (!strncasecmp(cur_rate,
+ cfg_hw_supported_rates[i].name,
+ XENSND_SAMPLE_RATE_MAX_LEN)) {
+ cur_mask = cfg_hw_supported_rates[i].mask;
+ cur_value = cfg_hw_supported_rates[i].value;
+ rates |= cur_mask;
+ if (rate_min > cur_value)
+ rate_min = cur_value;
+ if (rate_max < cur_value)
+ rate_max = cur_value;
+ }
+ }
+
+ if (rates) {
+ pcm_hw->rates = rates;
+ pcm_hw->rate_min = rate_min;
+ pcm_hw->rate_max = rate_max;
+ }
+}
+
+static void cfg_formats(char *list, unsigned int len,
+ const char *path, struct snd_pcm_hardware *pcm_hw)
+{
+ u64 formats;
+ char *cur_format;
+ int i;
+
+ formats = 0;
+ while ((cur_format = strsep(&list, XENSND_LIST_SEPARATOR))) {
+ for (i = 0; i < ARRAY_SIZE(cfg_hw_supported_formats); i++)
+ if (!strncasecmp(cur_format,
+ cfg_hw_supported_formats[i].name,
+ XENSND_SAMPLE_FORMAT_MAX_LEN))
+ formats |= cfg_hw_supported_formats[i].mask;
+ }
+
+ if (formats)
+ pcm_hw->formats = formats;
+}
+
+static void cfg_pcm_hw(const char *path,
+ struct snd_pcm_hardware *parent_pcm_hw,
+ struct snd_pcm_hardware *pcm_hw)
+{
+ char *list;
+ int val;
+ size_t buf_sz;
+ unsigned int len;
+
+ /* inherit parent's PCM HW and read overrides if any */
+ *pcm_hw = *parent_pcm_hw;
+
+ val = xenbus_read_unsigned(path, XENSND_FIELD_CHANNELS_MIN, 0);
+ if (val)
+ pcm_hw->channels_min = val;
+
+ val = xenbus_read_unsigned(path, XENSND_FIELD_CHANNELS_MAX, 0);
+ if (val)
+ pcm_hw->channels_max = val;
+
+ list = xenbus_read(XBT_NIL, path, XENSND_FIELD_SAMPLE_RATES, &len);
+ if (!IS_ERR(list)) {
+ cfg_hw_rates(list, len, path, pcm_hw);
+ kfree(list);
+ }
+
+ list = xenbus_read(XBT_NIL, path, XENSND_FIELD_SAMPLE_FORMATS, &len);
+ if (!IS_ERR(list)) {
+ cfg_formats(list, len, path, pcm_hw);
+ kfree(list);
+ }
+
+ buf_sz = xenbus_read_unsigned(path, XENSND_FIELD_BUFFER_SIZE, 0);
+ if (buf_sz)
+ pcm_hw->buffer_bytes_max = buf_sz;
+}
+
+static int cfg_get_stream_type(const char *path, int index,
+ int *num_pb, int *num_cap)
+{
+ char *str = NULL;
+ char *stream_path;
+ int ret;
+
+ *num_pb = 0;
+ *num_cap = 0;
+ stream_path = kasprintf(GFP_KERNEL, "%s/%d", path, index);
+ if (!stream_path) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ str = xenbus_read(XBT_NIL, stream_path, XENSND_FIELD_TYPE, NULL);
+ if (IS_ERR(str)) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
+ sizeof(XENSND_STREAM_TYPE_PLAYBACK)))
+ (*num_pb)++;
+ else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
+ sizeof(XENSND_STREAM_TYPE_CAPTURE)))
+ (*num_cap)++;
+ else {
+ ret = -EINVAL;
+ goto fail;
+ }
+ ret = 0;
+
+fail:
+ kfree(stream_path);
+ kfree(str);
+ return ret;
+}
+
+static int cfg_stream(struct xdrv_info *drv_info,
+ struct cfg_pcm_instance *pcm_instance,
+ const char *path, int index, int *cur_pb, int *cur_cap,
+ int *stream_idx)
+{
+ char *str = NULL;
+ char *stream_path;
+ struct cfg_stream *stream;
+ int ret;
+
+ stream_path = devm_kasprintf(&drv_info->xb_dev->dev,
+ GFP_KERNEL, "%s/%d", path, index);
+ if (!stream_path) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ str = xenbus_read(XBT_NIL, stream_path, XENSND_FIELD_TYPE, NULL);
+ if (IS_ERR(str)) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
+ sizeof(XENSND_STREAM_TYPE_PLAYBACK))) {
+ stream = &pcm_instance->streams_pb[(*cur_pb)++];
+ } else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
+ sizeof(XENSND_STREAM_TYPE_CAPTURE))) {
+ stream = &pcm_instance->streams_cap[(*cur_cap)++];
+ } else {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ /* get next stream index */
+ stream->unique_id = (*stream_idx)++;
+ stream->xenstore_path = stream_path;
+ /*
+ * check in Xen store if PCM HW configuration exists for this stream
+ * and update if so, e.g. we inherit all values from device's PCM HW,
+ * but can still override some of the values for the stream
+ */
+ cfg_pcm_hw(stream->xenstore_path,
+ &pcm_instance->pcm_hw, &stream->pcm_hw);
+ ret = 0;
+
+fail:
+ kfree(str);
+ return ret;
+}
+
+static int cfg_device(struct xdrv_info *drv_info,
+ struct cfg_pcm_instance *pcm_instance,
+ struct snd_pcm_hardware *parent_pcm_hw,
+ const char *path, int node_index, int *stream_idx)
+{
+ char *str;
+ char *device_path;
+ int ret, i, num_streams;
+ int num_pb, num_cap;
+ int cur_pb, cur_cap;
+ char node[3];
+
+ device_path = kasprintf(GFP_KERNEL, "%s/%d", path, node_index);
+ if (!device_path)
+ return -ENOMEM;
+
+ str = xenbus_read(XBT_NIL, device_path, XENSND_FIELD_DEVICE_NAME, NULL);
+ if (!IS_ERR(str)) {
+ strncpy(pcm_instance->name, str, sizeof(pcm_instance->name));
+ kfree(str);
+ }
+
+ pcm_instance->device_id = node_index;
+
+ /*
+ * check in Xen store if PCM HW configuration exists for this device
+ * and update if so, e.g. we inherit all values from card's PCM HW,
+ * but can still override some of the values for the device
+ */
+ cfg_pcm_hw(device_path, parent_pcm_hw, &pcm_instance->pcm_hw);
+
+ /*
+ * find out how many streams were configured in Xen store:
+ * streams must have sequential unique IDs, so stop when one
+ * does not exist
+ */
+ num_streams = 0;
+ do {
+ snprintf(node, sizeof(node), "%d", num_streams);
+ if (!xenbus_exists(XBT_NIL, device_path, node))
+ break;
+
+ num_streams++;
+ } while (num_streams < VSND_MAX_STREAM);
+
+ pcm_instance->num_streams_pb = 0;
+ pcm_instance->num_streams_cap = 0;
+ /* get number of playback and capture streams */
+ for (i = 0; i < num_streams; i++) {
+ ret = cfg_get_stream_type(device_path, i, &num_pb, &num_cap);
+ if (ret < 0)
+ goto fail;
+
+ pcm_instance->num_streams_pb += num_pb;
+ pcm_instance->num_streams_cap += num_cap;
+ }
+
+ if (pcm_instance->num_streams_pb) {
+ pcm_instance->streams_pb = devm_kcalloc(
+ &drv_info->xb_dev->dev,
+ pcm_instance->num_streams_pb,
+ sizeof(struct cfg_stream), GFP_KERNEL);
+ if (!pcm_instance->streams_pb) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ if (pcm_instance->num_streams_cap) {
+ pcm_instance->streams_cap = devm_kcalloc(
+ &drv_info->xb_dev->dev,
+ pcm_instance->num_streams_cap,
+ sizeof(struct cfg_stream), GFP_KERNEL);
+ if (!pcm_instance->streams_cap) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ cur_pb = 0;
+ cur_cap = 0;
+ for (i = 0; i < num_streams; i++) {
+ ret = cfg_stream(drv_info,
+ pcm_instance, device_path, i, &cur_pb, &cur_cap,
+ stream_idx);
+ if (ret < 0)
+ goto fail;
+ }
+ ret = 0;
+
+fail:
+ kfree(device_path);
+ return ret;
+}
+
+static int cfg_card(struct xdrv_info *drv_info,
+ struct sdev_card_plat_data *plat_data, int *stream_idx)
+{
+ struct xenbus_device *xb_dev = drv_info->xb_dev;
+ int ret, num_devices, i;
+ char node[3];
+
+ num_devices = 0;
+ do {
+ snprintf(node, sizeof(node), "%d", num_devices);
+ if (!xenbus_exists(XBT_NIL, xb_dev->nodename, node))
+ break;
+
+ num_devices++;
+ } while (num_devices < SNDRV_PCM_DEVICES);
+
+ if (!num_devices) {
+ dev_warn(&xb_dev->dev,
+ "No devices configured for sound card at %s\n",
+ xb_dev->nodename);
+ return -ENODEV;
+ }
+
+ /* start from default PCM HW configuration for the card */
+ cfg_pcm_hw(xb_dev->nodename, &sdrv_pcm_hw_default,
+ &plat_data->cfg_card.pcm_hw);
+
+ plat_data->cfg_card.pcm_instances = devm_kcalloc(
+ &drv_info->xb_dev->dev, num_devices,
+ sizeof(struct cfg_pcm_instance), GFP_KERNEL);
+ if (!plat_data->cfg_card.pcm_instances)
+ return -ENOMEM;
+
+ for (i = 0; i < num_devices; i++) {
+ ret = cfg_device(drv_info,
+ &plat_data->cfg_card.pcm_instances[i],
+ &plat_data->cfg_card.pcm_hw,
+ xb_dev->nodename, i, stream_idx);
+ if (ret < 0)
+ return ret;
+ }
+ plat_data->cfg_card.num_pcm_instances = num_devices;
+ return 0;
+}
+
static void xdrv_remove_internal(struct xdrv_info *drv_info)
{
}

static int xdrv_be_on_initwait(struct xdrv_info *drv_info)
{
+ int stream_idx;
+ int ret;
+
+ drv_info->cfg_plat_data.xdrv_info = drv_info;
+ stream_idx = 0;
+ ret = cfg_card(drv_info, &drv_info->cfg_plat_data, &stream_idx);
+ if (ret < 0)
+ return ret;
return 0;
}

--
2.7.4