Revert "ALSA: usb-audio: Improve frames size computation"

This reverts commit aba41867dd66939d336fdf604e4d73b805d8039f which is
commit f0bd62b64016508938df9babe47f65c2c727d25c upstream.

It causes a number of reported issues and a fix for it has not hit
Linus's tree yet.  Revert this to resolve those problems.

Cc: Alexander Tsoy <alexander@tsoy.me>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Hans de Goede <jwrdegoede@fedoraproject.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[sw0312.kim: cherry-pick linux-5.4.y commit e0ed5a36fb3a to fix specific usb-audio distortion issue]
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Change-Id: I9e7ca39dddc28d8c29bf0488419c1fbdbddfb61a

diff --git a/sound/usb/card.h b/sound/usb/card.h
index d6219fb..f39f23e 100644 (file)
--- a/sound/usb/card.h
+++ b/sound/usb/card.h
@@ -84,10 +84,6 @@ struct snd_usb_endpoint {
        dma_addr_t sync_dma;            /* DMA address of syncbuf */
 
        unsigned int pipe;              /* the data i/o pipe */
-       unsigned int framesize[2];      /* small/large frame sizes in samples */
-       unsigned int sample_rem;        /* remainder from division fs/fps */
-       unsigned int sample_accum;      /* sample accumulator */
-       unsigned int fps;               /* frames per second */
        unsigned int freqn;             /* nominal sampling rate in fs/fps in Q16.16 format */
        unsigned int freqm;             /* momentary sampling rate in fs/fps in Q16.16 format */
        int        freqshift;           /* how much to shift the feedback value to get Q16.16 */

diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index 9bea7d3..87cc249 100644 (file)
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -124,12 +124,12 @@ int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
 
 /*
  * For streaming based on information derived from sync endpoints,
- * prepare_outbound_urb_sizes() will call slave_next_packet_size() to
+ * prepare_outbound_urb_sizes() will call next_packet_size() to
  * determine the number of samples to be sent in the next packet.
  *
- * For implicit feedback, slave_next_packet_size() is unused.
+ * For implicit feedback, next_packet_size() is unused.
  */
-int snd_usb_endpoint_slave_next_packet_size(struct snd_usb_endpoint *ep)
+int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep)
 {
        unsigned long flags;
        int ret;
@@ -146,29 +146,6 @@ int snd_usb_endpoint_slave_next_packet_size(struct snd_usb_endpoint *ep)
        return ret;
 }
 
-/*
- * For adaptive and synchronous endpoints, prepare_outbound_urb_sizes()
- * will call next_packet_size() to determine the number of samples to be
- * sent in the next packet.
- */
-int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep)
-{
-       int ret;
-
-       if (ep->fill_max)
-               return ep->maxframesize;
-
-       ep->sample_accum += ep->sample_rem;
-       if (ep->sample_accum >= ep->fps) {
-               ep->sample_accum -= ep->fps;
-               ret = ep->framesize[1];
-       } else {
-               ret = ep->framesize[0];
-       }
-
-       return ret;
-}
-
 static void retire_outbound_urb(struct snd_usb_endpoint *ep,
                                struct snd_urb_ctx *urb_ctx)
 {
@@ -213,8 +190,6 @@ static void prepare_silent_urb(struct snd_usb_endpoint *ep,
 
                if (ctx->packet_size[i])
                        counts = ctx->packet_size[i];
-               else if (ep->sync_master)
-                       counts = snd_usb_endpoint_slave_next_packet_size(ep);
                else
                        counts = snd_usb_endpoint_next_packet_size(ep);
 
@@ -1086,17 +1061,10 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
        ep->maxpacksize = fmt->maxpacksize;
        ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
 
-       if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL) {
+       if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
                ep->freqn = get_usb_full_speed_rate(rate);
-               ep->fps = 1000;
-       } else {
+       else
                ep->freqn = get_usb_high_speed_rate(rate);
-               ep->fps = 8000;
-       }
-
-       ep->sample_rem = rate % ep->fps;
-       ep->framesize[0] = rate / ep->fps;
-       ep->framesize[1] = (rate + (ep->fps - 1)) / ep->fps;
 
        /* calculate the frequency in 16.16 format */
        ep->freqm = ep->freqn;
@@ -1155,7 +1123,6 @@ int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
        ep->active_mask = 0;
        ep->unlink_mask = 0;
        ep->phase = 0;
-       ep->sample_accum = 0;
 
        snd_usb_endpoint_start_quirk(ep);
 

diff --git a/sound/usb/endpoint.h b/sound/usb/endpoint.h
index d23fa0a..63a39d4 100644 (file)
--- a/sound/usb/endpoint.h
+++ b/sound/usb/endpoint.h
@@ -28,7 +28,6 @@ void snd_usb_endpoint_release(struct snd_usb_endpoint *ep);
 void snd_usb_endpoint_free(struct snd_usb_endpoint *ep);
 
 int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep);
-int snd_usb_endpoint_slave_next_packet_size(struct snd_usb_endpoint *ep);
 int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep);
 
 void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,

diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index b971d9a..426c55b 100644 (file)
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -1581,8 +1581,6 @@ static void prepare_playback_urb(struct snd_usb_substream *subs,
        for (i = 0; i < ctx->packets; i++) {
                if (ctx->packet_size[i])
                        counts = ctx->packet_size[i];
-               else if (ep->sync_master)
-                       counts = snd_usb_endpoint_slave_next_packet_size(ep);
                else
                        counts = snd_usb_endpoint_next_packet_size(ep);