[PATCH 3/3] ASoC: fsl_sai: Select sleep pinctrl state during runtime suspend

[Fabio Estevam <festevam@gmail.com>]

When runtime suspended, the SAI can leave its outputs at their last
levels. If a connected device is unpowered, those signals can source
current through its input protection circuitry.

Select the sleep pinctrl state after gating the clocks, and restore the
default state before enabling them on runtime resume. Devices without
a sleep state continue to use their existing pin configuration.

The pin-state issue was reproduced on a custom i.MX8MP board.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
---
 sound/soc/fsl/fsl_sai.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c
index a135b3da37cf..ad21bd3b8a5d 100644
--- a/sound/soc/fsl/fsl_sai.c
+++ b/sound/soc/fsl/fsl_sai.c
@@ -1959,6 +1959,7 @@ static int fsl_sai_runtime_suspend(struct device *dev)
 		cpu_latency_qos_remove_request(&sai->pm_qos_req);
 
 	regcache_cache_only(sai->regmap, true);
+	pinctrl_pm_select_sleep_state(dev);
 
 	return 0;
 }
@@ -1969,6 +1970,8 @@ static int fsl_sai_runtime_resume(struct device *dev)
 	unsigned int ofs = sai->soc_data->reg_offset;
 	int ret;
 
+	pinctrl_pm_select_default_state(dev);
+
 	ret = clk_prepare_enable(sai->bus_clk);
 	if (ret) {
 		dev_err(dev, "failed to enable bus clock: %d\n", ret);
-- 
2.43.0