[RFC PATCH 2/3] ASoC: Intel: bdw-rt5677: fix module load/unload issues

[Pierre-Louis Bossart]

The use of devm_gpiod_get() in a dailink .init() callback generates issues
when unloading modules. The dependencies between modules are not well
handled and the snd_soc_rt5677 module cannot be removed:

rmmod: ERROR: Module snd_soc_rt5677 is in use

Removing the use of devm_ and manually releasing the gpio descriptor
in the dailink .exit() callback solves the issue.

Tested on SAMUS Chromebook with SOF driver.

Suggested-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
---
 sound/soc/intel/boards/bdw-rt5677.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/sound/soc/intel/boards/bdw-rt5677.c b/sound/soc/intel/boards/bdw-rt5677.c
index a94f498388e1..641491cb449b 100644
--- a/sound/soc/intel/boards/bdw-rt5677.c
+++ b/sound/soc/intel/boards/bdw-rt5677.c
@@ -247,8 +247,8 @@ static int bdw_rt5677_init(struct snd_soc_pcm_runtime *rtd)
 			RT5677_CLK_SEL_SYS2);
 
 	/* Request rt5677 GPIO for headphone amp control */
-	bdw_rt5677->gpio_hp_en = devm_gpiod_get(component->dev, "headphone-enable",
-						GPIOD_OUT_LOW);
+	bdw_rt5677->gpio_hp_en = gpiod_get(component->dev, "headphone-enable",
+					   GPIOD_OUT_LOW);
 	if (IS_ERR(bdw_rt5677->gpio_hp_en)) {
 		dev_err(component->dev, "Can't find HP_AMP_SHDN_L gpio\n");
 		return PTR_ERR(bdw_rt5677->gpio_hp_en);
@@ -282,6 +282,15 @@ static int bdw_rt5677_init(struct snd_soc_pcm_runtime *rtd)
 	return 0;
 }
 
+static void bdw_rt5677_exit(struct snd_soc_pcm_runtime *rtd)
+{
+	struct bdw_rt5677_priv *bdw_rt5677 =
+			snd_soc_card_get_drvdata(rtd->card);
+
+	if (!IS_ERR(bdw_rt5677->gpio_hp_en))
+		gpiod_put(bdw_rt5677->gpio_hp_en);
+}
+
 /* broadwell digital audio interface glue - connects codec <--> CPU */
 SND_SOC_DAILINK_DEF(dummy,
 	DAILINK_COMP_ARRAY(COMP_DUMMY()));
@@ -350,6 +359,7 @@ static struct snd_soc_dai_link bdw_rt5677_dais[] = {
 		.dpcm_playback = 1,
 		.dpcm_capture = 1,
 		.init = bdw_rt5677_init,
+		.exit = bdw_rt5677_exit,
 		SND_SOC_DAILINK_REG(ssp0_port, be, platform),
 	},
 };
-- 
2.20.1