From 4106820b90ab0f963571d14bdbf9a2587ca80532 Mon Sep 17 00:00:00 2001
From: Mohan Kumar <mkumard@nvidia.com>
Date: Wed, 5 Aug 2020 15:22:20 +0530
Subject: [PATCH] ALSA: hda: Add dma stop delay variable
Git-commit: 4106820b90ab0f963571d14bdbf9a2587ca80532
Patch-mainline: v5.9-rc1
References: jsc#SLE-16518
A variable dma_stop_delay is added as a new member in hdac_bus
structure to avoid memory decode error incase DMA RUN bit is not
disabled in the given timeout from snd_hdac_stream_sync function and
followed by stream reset which results in memory decode error between
reset set and clear operation.
Signed-off-by: Mohan Kumar <mkumard@nvidia.com>
Link: https://lore.kernel.org/r/20200805095221.5476-3-mkumard@nvidia.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
include/sound/hdaudio.h | 3 +++
sound/hda/hdac_stream.c | 7 +++++++
2 files changed, 10 insertions(+)
diff --git a/include/sound/hdaudio.h b/include/sound/hdaudio.h
index c1f78d9a6e47..6eed61e6cf8a 100644
--- a/include/sound/hdaudio.h
+++ b/include/sound/hdaudio.h
@@ -347,6 +347,9 @@ struct hdac_bus {
int bdl_pos_adj; /* BDL position adjustment */
+ /* delay time in us for dma stop */
+ unsigned int dma_stop_delay;
+
/* locks */
spinlock_t reg_lock;
struct mutex cmd_mutex;
diff --git a/sound/hda/hdac_stream.c b/sound/hda/hdac_stream.c
index a38a2af1654f..abe7a1b16fe1 100644
--- a/sound/hda/hdac_stream.c
+++ b/sound/hda/hdac_stream.c
@@ -150,9 +150,12 @@ void snd_hdac_stream_reset(struct hdac_stream *azx_dev)
{
unsigned char val;
int timeout;
+ int dma_run_state;
snd_hdac_stream_clear(azx_dev);
+ dma_run_state = snd_hdac_stream_readb(azx_dev, SD_CTL) & SD_CTL_DMA_START;
+
snd_hdac_stream_updateb(azx_dev, SD_CTL, 0, SD_CTL_STREAM_RESET);
udelay(3);
timeout = 300;
@@ -162,6 +165,10 @@ void snd_hdac_stream_reset(struct hdac_stream *azx_dev)
if (val)
break;
} while (--timeout);
+
+ if (azx_dev->bus->dma_stop_delay && dma_run_state)
+ udelay(azx_dev->bus->dma_stop_delay);
+
val &= ~SD_CTL_STREAM_RESET;
snd_hdac_stream_writeb(azx_dev, SD_CTL, val);
udelay(3);
--
2.16.4