Patch "ASoC: ti: davinci-mcasp: Set min period size using FIFO config" has been added to the 6.9-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ASoC: ti: davinci-mcasp: Set min period size using FIFO config

to the 6.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     asoc-ti-davinci-mcasp-set-min-period-size-using-fifo.patch
and it can be found in the queue-6.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 6eba7d7fa646f0898f352aae023642710842c2c4
Author: Jai Luthra <j-luthra@xxxxxx>
Date:   Tue Jun 11 18:02:56 2024 +0530

    ASoC: ti: davinci-mcasp: Set min period size using FIFO config
    
    [ Upstream commit c5dcf8ab10606e76c1d8a0ec77f27d84a392e874 ]
    
    The minimum period size was enforced to 64 as older devices integrating
    McASP with EDMA used an internal FIFO of 64 samples.
    
    With UDMA based platforms this internal McASP FIFO is optional, as the
    DMA engine internally does some buffering which is already accounted for
    when registering the platform. So we should read the actual FIFO
    configuration (txnumevt/rxnumevt) instead of hardcoding frames.min to
    64.
    
    Acked-by: Peter Ujfalusi <peter.ujfalusi@xxxxxxxxx>
    Signed-off-by: Jai Luthra <j-luthra@xxxxxx>
    Link: https://lore.kernel.org/r/20240611-asoc_next-v3-2-fcfd84b12164@xxxxxx
    Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c
index 1e760c3155213..2b1ed91a736c9 100644
--- a/sound/soc/ti/davinci-mcasp.c
+++ b/sound/soc/ti/davinci-mcasp.c
@@ -1472,10 +1472,11 @@ static int davinci_mcasp_hw_rule_min_periodsize(
 {
 	struct snd_interval *period_size = hw_param_interval(params,
 						SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
+	u8 numevt = *((u8 *)rule->private);
 	struct snd_interval frames;
 
 	snd_interval_any(&frames);
-	frames.min = 64;
+	frames.min = numevt;
 	frames.integer = 1;
 
 	return snd_interval_refine(period_size, &frames);
@@ -1490,6 +1491,7 @@ static int davinci_mcasp_startup(struct snd_pcm_substream *substream,
 	u32 max_channels = 0;
 	int i, dir, ret;
 	int tdm_slots = mcasp->tdm_slots;
+	u8 *numevt;
 
 	/* Do not allow more then one stream per direction */
 	if (mcasp->substreams[substream->stream])
@@ -1589,9 +1591,12 @@ static int davinci_mcasp_startup(struct snd_pcm_substream *substream,
 			return ret;
 	}
 
+	numevt = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
+			 &mcasp->txnumevt :
+			 &mcasp->rxnumevt;
 	snd_pcm_hw_rule_add(substream->runtime, 0,
 			    SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
-			    davinci_mcasp_hw_rule_min_periodsize, NULL,
+			    davinci_mcasp_hw_rule_min_periodsize, numevt,
 			    SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
 
 	return 0;