[RESEND PATCH] ASoC: core: Exit all links before removing their components

[Cezary Rojewski]

Flows leading to link->init() and link->exit() are not symmetric.
Currently the relevant part of card probe sequence goes as:

	for_each_card_rtds(card, rtd)
		for_each_rtd_components(rtd, i, component)
			component->probe()
	for_each_card_rtds(card, rtd)
		for_each_rtd_dais(rtd, i, dai)
			dai->probe()
	for_each_card_rtds(card, rtd)
		rtd->init()

On the other side, equivalent remove sequence goes as:

	for_each_card_rtds(card, rtd)
		for_each_rtd_dais(rtd, i, dai)
			dai->remove()
	for_each_card_rtds(card, rtd)
		for_each_rtd_components(rtd, i, component)
			component->remove()
	for_each_card_rtds(card, rtd)
		rtd->exit()

what can lead to errors as link->exit() may still operate on resources
owned by its components despite the probability of them being freed
during the component->remove().

This change modifies the remove sequence to:

	for_each_card_rtds(card, rtd)
		rtd->exit()
	for_each_card_rtds(card, rtd)
		for_each_rtd_dais(rtd, i, dai)
			dai->remove()
	for_each_card_rtds(card, rtd)
		for_each_rtd_components(rtd, i, component)
			component->remove()

so code found in link->exit() is safe to touch any component stuff as
component->remove() has not been called yet.

Signed-off-by: Cezary Rojewski <cezary.rojewski at intel.com>
Reviewed-by: Amadeusz Sławiński <amadeuszx.slawinski at linux.intel.com>
---

Original review for v1:
https://lore.kernel.org/alsa-devel/20220621115758.3154933-1-cezary.rojewski@intel.com/

 sound/soc/soc-core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 4a3fca50a536..638e781df3b0 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -935,9 +935,6 @@ void snd_soc_remove_pcm_runtime(struct snd_soc_card *card,
 {
 	lockdep_assert_held(&client_mutex);
 
-	/* release machine specific resources */
-	snd_soc_link_exit(rtd);
-
 	/*
 	 * Notify the machine driver for extra destruction
 	 */
@@ -1888,6 +1885,9 @@ static void soc_cleanup_card_resources(struct snd_soc_card *card)
 
 	snd_soc_dapm_shutdown(card);
 
+	/* release machine specific resources */
+	for_each_card_rtds(card, rtd)
+		snd_soc_link_exit(rtd);
 	/* remove and free each DAI */
 	soc_remove_link_dais(card);
 	soc_remove_link_components(card);
-- 
2.25.1