From: Jeeja KP <jeeja.kp@xxxxxxxxx>
If the DMAs are not being quiesced properly, it may lead to
stability issues, so the recommendation is to wait till DMAs are
stopped.
After setting the stop bit of RIRB/CORB DMA, we should wait for
stop bit to be set.
Signed-off-by: Jeeja KP <jeeja.kp@xxxxxxxxx>
Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx>
---
changes in v2:
- use common wait routine as suggested by Takashi
sound/hda/hdac_controller.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/sound/hda/hdac_controller.c b/sound/hda/hdac_controller.c
index 8c486235c905..9fee464e5d49 100644
--- a/sound/hda/hdac_controller.c
+++ b/sound/hda/hdac_controller.c
@@ -80,6 +80,22 @@ void snd_hdac_bus_init_cmd_io(struct hdac_bus *bus)
}
EXPORT_SYMBOL_GPL(snd_hdac_bus_init_cmd_io);
+/* wait for cmd dmas till they are stopped */
+static void hdac_wait_for_cmd_dmas(struct hdac_bus *bus)
+{
+ unsigned long timeout;
+
+ timeout = jiffies + msecs_to_jiffies(100);
+ while ((snd_hdac_chip_readb(bus, RIRBCTL) & AZX_RBCTL_DMA_EN)
+ && time_before(jiffies, timeout))
+ udelay(10);
+
+ timeout = jiffies + msecs_to_jiffies(100);
+ while ((snd_hdac_chip_readb(bus, CORBCTL) & AZX_CORBCTL_RUN)
+ && time_before(jiffies, timeout))
+ udelay(10);
+}
+
/**
* snd_hdac_bus_stop_cmd_io - clean up CORB/RIRB buffers
* @bus: HD-audio core bus
@@ -90,6 +106,7 @@ void snd_hdac_bus_stop_cmd_io(struct hdac_bus *bus)
/* disable ringbuffer DMAs */
snd_hdac_chip_writeb(bus, RIRBCTL, 0);
snd_hdac_chip_writeb(bus, CORBCTL, 0);
+ hdac_wait_for_cmd_dmas(bus);
/* disable unsolicited responses */
snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_UNSOL, 0);
spin_unlock_irq(&bus->reg_lock);
--
1.9.1
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