sound: usb: Add snapshot for usb audio qmi driver
This change adds snapshot of usb audio qmi service related files.
A remote entity communicates with usb audio qmi server to enable
or disable particular audio stream on enumerated usb audio device.
This offloads ISOC data transfer operations to remote entity and
allows apps processor to go to power collapse more frequently for
better power saving. This snapshot is taken as of msm-4.14
commit <1216527842f1d> ("Merge "ARM: dts: msm: Add compute
priority mode and cooling devices in sm8150"").
Change-Id: I0d3c1c129723e2327406a61ae7c756736df99872
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index 3828471..afba778 100644
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -149,6 +149,69 @@
return found;
}
+/*
+ * find a matching audio format as well as non-zero service interval
+ */
+static struct audioformat *find_format_and_si(struct snd_usb_substream *subs,
+ unsigned int datainterval)
+{
+ unsigned int i;
+ struct audioformat *fp;
+ struct audioformat *found = NULL;
+ int cur_attr = 0, attr;
+
+ list_for_each_entry(fp, &subs->fmt_list, list) {
+ if (datainterval != fp->datainterval)
+ continue;
+ if (!(fp->formats & pcm_format_to_bits(subs->pcm_format)))
+ continue;
+ if (fp->channels != subs->channels)
+ continue;
+ if (subs->cur_rate < fp->rate_min ||
+ subs->cur_rate > fp->rate_max)
+ continue;
+ if (!(fp->rates & SNDRV_PCM_RATE_CONTINUOUS)) {
+ for (i = 0; i < fp->nr_rates; i++)
+ if (fp->rate_table[i] == subs->cur_rate)
+ break;
+ if (i >= fp->nr_rates)
+ continue;
+ }
+ attr = fp->ep_attr & USB_ENDPOINT_SYNCTYPE;
+ if (!found) {
+ found = fp;
+ cur_attr = attr;
+ continue;
+ }
+ /* avoid async out and adaptive in if the other method
+ * supports the same format.
+ * this is a workaround for the case like
+ * M-audio audiophile USB.
+ */
+ if (attr != cur_attr) {
+ if ((attr == USB_ENDPOINT_SYNC_ASYNC &&
+ subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
+ (attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
+ subs->direction == SNDRV_PCM_STREAM_CAPTURE))
+ continue;
+ if ((cur_attr == USB_ENDPOINT_SYNC_ASYNC &&
+ subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
+ (cur_attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
+ subs->direction == SNDRV_PCM_STREAM_CAPTURE)) {
+ found = fp;
+ cur_attr = attr;
+ continue;
+ }
+ }
+ /* find the format with the largest max. packet size */
+ if (fp->maxpacksize > found->maxpacksize) {
+ found = fp;
+ cur_attr = attr;
+ }
+ }
+ return found;
+}
+
static int init_pitch_v1(struct snd_usb_audio *chip, int iface,
struct usb_host_interface *alts,
struct audioformat *fmt)
@@ -565,6 +628,73 @@
return 0;
}
+int snd_usb_enable_audio_stream(struct snd_usb_substream *subs,
+ int datainterval, bool enable)
+{
+ struct audioformat *fmt;
+ struct usb_host_interface *alts;
+ struct usb_interface *iface;
+ int ret;
+
+ if (!enable) {
+ if (subs->interface >= 0) {
+ usb_set_interface(subs->dev, subs->interface, 0);
+ subs->altset_idx = 0;
+ subs->interface = -1;
+ subs->cur_audiofmt = NULL;
+ }
+
+ snd_usb_autosuspend(subs->stream->chip);
+ return 0;
+ }
+
+ snd_usb_autoresume(subs->stream->chip);
+ if (datainterval != -EINVAL)
+ fmt = find_format_and_si(subs, datainterval);
+ else
+ fmt = find_format(subs);
+ if (!fmt) {
+ dev_err(&subs->dev->dev,
+ "cannot set format: format = %#x, rate = %d, channels = %d\n",
+ subs->pcm_format, subs->cur_rate, subs->channels);
+ return -EINVAL;
+ }
+
+ subs->altset_idx = 0;
+ subs->interface = -1;
+ if (atomic_read(&subs->stream->chip->shutdown)) {
+ ret = -ENODEV;
+ } else {
+ ret = set_format(subs, fmt);
+ if (ret < 0)
+ return ret;
+
+ iface = usb_ifnum_to_if(subs->dev, subs->cur_audiofmt->iface);
+ if (!iface) {
+ dev_err(&subs->dev->dev, "Could not get iface %d\n",
+ subs->cur_audiofmt->iface);
+ return -ENODEV;
+ }
+
+ alts = &iface->altsetting[subs->cur_audiofmt->altset_idx];
+ ret = snd_usb_init_sample_rate(subs->stream->chip,
+ subs->cur_audiofmt->iface,
+ alts,
+ subs->cur_audiofmt,
+ subs->cur_rate);
+ if (ret < 0) {
+ dev_err(&subs->dev->dev, "failed to set rate %d\n",
+ subs->cur_rate);
+ return ret;
+ }
+ }
+
+ subs->interface = fmt->iface;
+ subs->altset_idx = fmt->altset_idx;
+
+ return 0;
+}
+
/*
* Return the score of matching two audioformats.
* Veto the audioformat if: