2020-08-19 15:33:35

by Sameer Pujar

Subject: [PATCH v2] ALSA: hda: avoid reset of sdo_limit

By default 'sdo_limit' is initialized with a default value of '8'
as per spec. This is overridden in cases where a different value is
required. However this is getting reset when snd_hdac_bus_init_chip()
is called again, which happens during runtime PM cycle.

Avoid this reset by moving 'sdo_limit' setup to 'snd_hdac_bus_init()'
function which would be called only once.

Fixes: 67ae482a59e9 ("ALSA: hda: add member to store ratio for stripe control")
Cc: <[email protected]>
Signed-off-by: Sameer Pujar <[email protected]>
---
sound/hda/hdac_bus.c | 12 ++++++++++++
sound/hda/hdac_controller.c | 11 -----------
2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/sound/hda/hdac_bus.c b/sound/hda/hdac_bus.c
index 09ddab5..9766f6a 100644
--- a/sound/hda/hdac_bus.c
+++ b/sound/hda/hdac_bus.c
@@ -46,6 +46,18 @@ int snd_hdac_bus_init(struct hdac_bus *bus, struct device *dev,
INIT_LIST_HEAD(&bus->hlink_list);
init_waitqueue_head(&bus->rirb_wq);
bus->irq = -1;
+
+ /*
+ * Default value of '8' is as per the HD audio specification (Rev 1.0a).
+ * Following relation is used to derive STRIPE control value.
+ * For sample rate <= 48K:
+ * { ((num_channels * bits_per_sample) / number of SDOs) >= 8 }
+ * For sample rate > 48K:
+ * { ((num_channels * bits_per_sample * rate/48000) /
+ * number of SDOs) >= 8 }
+ */
+ bus->sdo_limit = 8;
+
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_bus_init);
diff --git a/sound/hda/hdac_controller.c b/sound/hda/hdac_controller.c
index 011b17c..b98449f 100644
--- a/sound/hda/hdac_controller.c
+++ b/sound/hda/hdac_controller.c
@@ -529,17 +529,6 @@ bool snd_hdac_bus_init_chip(struct hdac_bus *bus, bool full_reset)

bus->chip_init = true;

- /*
- * Default value of '8' is as per the HD audio specification (Rev 1.0a).
- * Following relation is used to derive STRIPE control value.
- * For sample rate <= 48K:
- * { ((num_channels * bits_per_sample) / number of SDOs) >= 8 }
- * For sample rate > 48K:
- * { ((num_channels * bits_per_sample * rate/48000) /
- * number of SDOs) >= 8 }
- */
- bus->sdo_limit = 8;
-
return true;
}
EXPORT_SYMBOL_GPL(snd_hdac_bus_init_chip);
--
2.7.4

2020-08-19 15:39:19

by Takashi Iwai

Subject: Re: [PATCH v2] ALSA: hda: avoid reset of sdo_limit

On Wed, 19 Aug 2020 17:32:10 +0200,
Sameer Pujar wrote:
>
> By default 'sdo_limit' is initialized with a default value of '8'
> as per spec. This is overridden in cases where a different value is
> required. However this is getting reset when snd_hdac_bus_init_chip()
> is called again, which happens during runtime PM cycle.
>
> Avoid this reset by moving 'sdo_limit' setup to 'snd_hdac_bus_init()'
> function which would be called only once.
>
> Fixes: 67ae482a59e9 ("ALSA: hda: add member to store ratio for stripe control")
> Cc: <[email protected]>
> Signed-off-by: Sameer Pujar <[email protected]>

Applied now. Thanks.


Takashi