diff mbox series

[v4,3/9] ALSA: hda: Introduce snd_hdac_stream_wait_drsm()

Message ID 20221027124702.1761002-4-cezary.rojewski@intel.com (mailing list archive)
State Accepted
Commit efffb014478e76c35b1a9e279d7010f70ff517e2
Headers show
Series ASoC: Intel: avs: PCM power management | expand

Commit Message

Cezary Rojewski Oct. 27, 2022, 12:46 p.m. UTC 
Allow for waiting for DRSM bit for specified stream to be cleared from
HDAudio library level. Drivers may utilize this optional step during the
stream resume procedure.

Suggested-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
---

Changes in v4:
- replaced readb_poll_timeout() with read_poll_timeout() for the DRSM
  polling function as the register is u32 wide, not u8

 include/sound/hdaudio.h |  1 +
 sound/hda/hdac_stream.c | 22 ++++++++++++++++++++++
 2 files changed, 23 insertions(+)

Comments

Takashi Iwai Oct. 27, 2022, 1:31 p.m. UTC | #1 
On Thu, 27 Oct 2022 14:46:56 +0200,
Cezary Rojewski wrote:
> 
> Allow for waiting for DRSM bit for specified stream to be cleared from
> HDAudio library level. Drivers may utilize this optional step during the
> stream resume procedure.
> 
> Suggested-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
> ---
> 
> Changes in v4:
> - replaced readb_poll_timeout() with read_poll_timeout() for the DRSM
>   polling function as the register is u32 wide, not u8

Reviewed-by: Takashi Iwai <tiwai@suse.de>


thanks,

Takashi
diff mbox series

Patch

diff --git a/include/sound/hdaudio.h b/include/sound/hdaudio.h
index 78f1809a4ad6..a6872537724d 100644
--- a/include/sound/hdaudio.h
+++ b/include/sound/hdaudio.h
@@ -597,6 +597,7 @@  int snd_hdac_stream_get_spbmaxfifo(struct hdac_bus *bus,
 				   struct hdac_stream *azx_dev);
 void snd_hdac_stream_drsm_enable(struct hdac_bus *bus,
 				 bool enable, int index);
+int snd_hdac_stream_wait_drsm(struct hdac_stream *azx_dev);
 int snd_hdac_stream_set_dpibr(struct hdac_bus *bus,
 			      struct hdac_stream *azx_dev, u32 value);
 int snd_hdac_stream_set_lpib(struct hdac_stream *azx_dev, u32 value);
diff --git a/sound/hda/hdac_stream.c b/sound/hda/hdac_stream.c
index 35fe2bd582ac..3b250ee7f6a7 100644
--- a/sound/hda/hdac_stream.c
+++ b/sound/hda/hdac_stream.c
@@ -821,6 +821,28 @@  void snd_hdac_stream_drsm_enable(struct hdac_bus *bus,
 }
 EXPORT_SYMBOL_GPL(snd_hdac_stream_drsm_enable);
 
+/*
+ * snd_hdac_stream_wait_drsm - wait for HW to clear RSM for a stream
+ * @azx_dev: HD-audio core stream to await RSM for
+ *
+ * Returns 0 on success and -ETIMEDOUT upon a timeout.
+ */
+int snd_hdac_stream_wait_drsm(struct hdac_stream *azx_dev)
+{
+	struct hdac_bus *bus = azx_dev->bus;
+	u32 mask, reg;
+	int ret;
+
+	mask = 1 << azx_dev->index;
+
+	ret = read_poll_timeout(snd_hdac_reg_readl, reg, !(reg & mask), 250, 2000, false, bus,
+				bus->drsmcap + AZX_REG_DRSM_CTL);
+	if (ret)
+		dev_dbg(bus->dev, "polling RSM 0x%08x failed: %d\n", mask, ret);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(snd_hdac_stream_wait_drsm);
+
 /**
  * snd_hdac_stream_set_dpibr - sets the dpibr value of a stream
  * @bus: HD-audio core bus