Revert "usb: gadget: u_audio: remove cached period bytes value"

This reverts commit ad983d197d386070d172991e924b11ea12afd90e.
Required for clean picking of UAC opensource changes.

Change-Id: I5d59361d347616c29dc40dcded7e0b132faf42a4
Signed-off-by: Ajay Agarwal <ajaya@codeaurora.org>

1 files changed, 35 insertions, 5 deletions

diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c
index e9644137f720..717656e17afa 100644
--- a/drivers/usb/gadget/function/u_audio.c
+++ b/drivers/usb/gadget/function/u_audio.c
@@ -49,6 +49,8 @@ struct uac_rtd_params {
 
 	void *rbuf;
 
+	size_t period_size;
+
 	unsigned max_psize;	/* MaxPacketSize of endpoint */
 	struct uac_req *ureq;
 
@@ -90,6 +92,7 @@ static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
 	unsigned pending;
 	unsigned long flags;
 	unsigned int hw_ptr;
+	bool update_alsa = false;
 	int status = req->status;
 	struct uac_req *ur = req->context;
 	struct snd_pcm_substream *substream;
@@ -142,6 +145,11 @@ static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
 		req->actual = req->length;
 	}
 
+	pending = prm->hw_ptr % prm->period_size;
+	pending += req->actual;
+	if (pending >= prm->period_size)
+		update_alsa = true;
+
 	hw_ptr = prm->hw_ptr;
 
 	spin_unlock_irqrestore(&prm->lock, flags);
@@ -172,15 +180,14 @@ static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
 	spin_lock_irqsave(&prm->lock, flags);
 	/* update hw_ptr after data is copied to memory */
 	prm->hw_ptr = (hw_ptr + req->actual) % runtime->dma_bytes;
-	hw_ptr = prm->hw_ptr;
 	spin_unlock_irqrestore(&prm->lock, flags);
 
-	if ((hw_ptr % snd_pcm_lib_period_bytes(substream)) < req->actual)
-		snd_pcm_period_elapsed(substream);
-
 exit:
 	if (usb_ep_queue(ep, req, GFP_ATOMIC))
 		dev_err(uac->card->dev, "%d Error!\n", __LINE__);
+
+	if (update_alsa)
+		snd_pcm_period_elapsed(substream);
 }
 
 static int uac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
@@ -243,12 +250,35 @@ static snd_pcm_uframes_t uac_pcm_pointer(struct snd_pcm_substream *substream)
 static int uac_pcm_hw_params(struct snd_pcm_substream *substream,
 			       struct snd_pcm_hw_params *hw_params)
 {
-	return snd_pcm_lib_malloc_pages(substream,
+	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
+	struct uac_rtd_params *prm;
+	int err;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		prm = &uac->p_prm;
+	else
+		prm = &uac->c_prm;
+
+	err = snd_pcm_lib_malloc_pages(substream,
 					params_buffer_bytes(hw_params));
+	if (err >= 0)
+		prm->period_size = params_period_bytes(hw_params);
+
+	return err;
 }
 
 static int uac_pcm_hw_free(struct snd_pcm_substream *substream)
 {
+	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
+	struct uac_rtd_params *prm;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		prm = &uac->p_prm;
+	else
+		prm = &uac->c_prm;
+
+	prm->period_size = 0;
+
 	return snd_pcm_lib_free_pages(substream);
 }