Merge tag 'sound-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound

Pull sound updates from Takashi Iwai:
 "As shown in diffstat and logs, it was again a busy development cycle
  at this time, too. The most significant changes are still on-going
  refactoring / modernization works for ASoC core and drivers, but there
  are lots of other changes as well. Here we go, some highlights below:

  ASoC:

   - Quite a lot of cleanup / refactoring of ASoC core and APIs; most of
     them are systematic, but also including cleanups and modernization

   - A bulk of updates for some ASoC platforms, Freescale, sunxi and
     Intel SST/SOF

   - Initial support for Sound Open Firmware on i.MX8

   - Removal of deprecated w90x900 and nuc900 drivers

   - New support for Cirrus Logic CS47L15 and CS47L92, Freescale i.MX
     7ULP and 8MQ, Meson G12A and NXP UDA1334

  USB-audio:

   - More validations of descriptor units for hardening against bugs
     reported by fuzzers

   - PCM device assignment workaround for a past call-order change

   - Scarlett Gen2 mixer interface, a few more more quirks

  HD-audio:

   - Support for audio component with AMD/ATI and Nvidia HDMI codecs

   - Clean up HD-audio core and remove indirect access ops for Intel SOF

   - DMIC detection at probe; it would make systems automatically
     falling back to SST/SOF driver on devices that need DMIC handling.
     Needs a new Kconfig to set, and beware that it's still new and a
     bit experimental

  FireWire:

   - Lots of code refactoring and cleanups"

* tag 'sound-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (521 commits)
  ASoC: sdm845: remove unneeded semicolon
  ASoC: fsl_sai: Implement set_bclk_ratio
  ASoC: dmaengine: Replace strncpy() with strscpy_pad() for pcm->name
  ASoC: wcd9335: remove redundant use of ret variable
  ALSA: firewire-tascam: check intermediate state of clock status and retry
  ALSA: firewire-tascam: handle error code when getting current source of clock
  ASoC: hdmi-codec: Add an op to set callback function for plug event
  ASoC: rt5677: keep analog power register at SND_SOC_BIAS_OFF
  ASoC: rt5677: Remove magic number register writes
  ASoC: soc-core: self contained soc_unbind_aux_dev()
  ASoC: soc-core: add soc_unbind_aux_dev()
  ASoC: soc-core: self contained soc_bind_aux_dev()
  ASoC: soc-core: move soc_probe_link_dais() next to soc_remove_link_dais()
  ASoC: soc-core: self contained soc_probe_link_dais()
  ASoC: soc-core: add new soc_link_init()
  ASoC: soc-core: move soc_probe_dai() next to soc_remove_dai()
  ASoC: soc-core: self contained soc_remove_link_dais()
  ASoC: soc-core: self contained soc_remove_link_components()
  ASoC: soc-core: self contained soc_probe_link_components()
  ASoC: rt1308: make array pd static const, makes object smaller
  ...

1 files changed, 19 insertions, 0 deletions

diff --git a/sound/soc/generic/audio-graph-card.c b/sound/soc/generic/audio-graph-card.c
index 288df245b2f0..6007e6305735 100644
--- a/sound/soc/generic/audio-graph-card.c
+++ b/sound/soc/generic/audio-graph-card.c
@@ -129,6 +129,25 @@ static int asoc_simple_parse_dai(struct device_node *ep,
 	args.args[0]	= graph_get_dai_id(ep);
 	args.args_count	= (of_graph_get_endpoint_count(node) > 1);
 
+	/*
+	 * FIXME
+	 *
+	 * Here, dlc->dai_name is pointer to CPU/Codec DAI name.
+	 * If user unbinded CPU or Codec driver, but not for Sound Card,
+	 * dlc->dai_name is keeping unbinded CPU or Codec
+	 * driver's pointer.
+	 *
+	 * If user re-bind CPU or Codec driver again, ALSA SoC will try
+	 * to rebind Card via snd_soc_try_rebind_card(), but because of
+	 * above reason, it might can't bind Sound Card.
+	 * Because Sound Card is pointing to released dai_name pointer.
+	 *
+	 * To avoid this rebind Card issue,
+	 * 1) It needs to alloc memory to keep dai_name eventhough
+	 *    CPU or Codec driver was unbinded, or
+	 * 2) user need to rebind Sound Card everytime
+	 *    if he unbinded CPU or Codec.
+	 */
 	ret = snd_soc_get_dai_name(&args, &dlc->dai_name);
 	if (ret < 0)
 		return ret;