[PATCH] ASoC: Intel: bytcr_wm5102: Fix GPIO related probe-ordering problem

[Hans de Goede <hdegoede@redhat.com>]

The "wlf,spkvdd-ena" GPIO needed by the bytcr_wm5102 driver
is made available through a gpio-lookup table.

This gpio-lookup table is registered by drivers/mfd/arizona-spi.c, which
may get probed after the bytcr_wm5102 driver.

If the gpio-lookup table has not registered yet then the gpiod_get()
will return -ENOENT. Treat -ENOENT as -EPROBE_DEFER to still keep
things working in this case.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 sound/soc/intel/boards/bytcr_wm5102.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/sound/soc/intel/boards/bytcr_wm5102.c b/sound/soc/intel/boards/bytcr_wm5102.c
index 00384c6fbcaa..330c0ace1638 100644
--- a/sound/soc/intel/boards/bytcr_wm5102.c
+++ b/sound/soc/intel/boards/bytcr_wm5102.c
@@ -421,8 +421,17 @@ static int snd_byt_wm5102_mc_probe(struct platform_device *pdev)
 	priv->spkvdd_en_gpio = gpiod_get(codec_dev, "wlf,spkvdd-ena", GPIOD_OUT_LOW);
 	put_device(codec_dev);
 
-	if (IS_ERR(priv->spkvdd_en_gpio))
-		return dev_err_probe(dev, PTR_ERR(priv->spkvdd_en_gpio), "getting spkvdd-GPIO\n");
+	if (IS_ERR(priv->spkvdd_en_gpio)) {
+		ret = PTR_ERR(priv->spkvdd_en_gpio);
+		/*
+		 * The spkvdd gpio-lookup is registered by: drivers/mfd/arizona-spi.c,
+		 * so -ENOENT means that arizona-spi hasn't probed yet.
+		 */
+		if (ret == -ENOENT)
+			ret = -EPROBE_DEFER;
+
+		return dev_err_probe(dev, ret, "getting spkvdd-GPIO\n");
+	}
 
 	/* override platform name, if required */
 	byt_wm5102_card.dev = dev;
-- 
2.36.0