gusextreme still leaves its ISA PM callbacks disabled because the shared
GF1 core had no suspend and resume path suitable for PM recovery.

Resume on this board needs one extra step before the shared GF1 path can
touch the chip again: the ES1688 side must restore the GF1 routing. Split
that routing sequence into a helper, reuse it for probe and resume, reset
the ES1688 side first on resume, and then wire the driver up to the shared
GUS PM helpers.

This restores usable post-resume GF1 operation on GUS Extreme without
rerunning probe-only detection in the shared GF1 path.

Signed-off-by: Cássio Gabriel <cassiogabrielcontato@gmail.com>
---
 sound/isa/gus/gusextreme.c | 57 ++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 48 insertions(+), 9 deletions(-)

diff --git a/sound/isa/gus/gusextreme.c b/sound/isa/gus/gusextreme.c
index ed921b89b00a..0984731740c4 100644
--- a/sound/isa/gus/gusextreme.c
+++ b/sound/isa/gus/gusextreme.c
@@ -44,6 +44,11 @@ static int joystick_dac[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 29};
 static int channels[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 24};
 static int pcm_channels[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
 
+struct snd_gusextreme {
+	struct snd_es1688 es1688;
+	struct snd_gus_card *gus;
+};
+
 module_param_array(index, int, NULL, 0444);
 MODULE_PARM_DESC(index, "Index value for " CRD_NAME " soundcard.");
 module_param_array(id, charp, NULL, 0444);
@@ -142,17 +147,15 @@ static int snd_gusextreme_gus_card_create(struct snd_card *card,
 			0, channels[n], pcm_channels[n], 0, rgus);
 }
 
-static int snd_gusextreme_detect(struct snd_gus_card *gus,
-				 struct snd_es1688 *es1688)
+static void snd_gusextreme_enable_gf1(struct snd_gus_card *gus,
+				      struct snd_es1688 *es1688)
 {
-	unsigned char d;
-
 	/*
 	 * This is main stuff - enable access to GF1 chip...
 	 * I'm not sure, if this will work for card which have
 	 * ES1688 chip in another place than 0x220.
-         *
-         * I used reverse-engineering in DOSEMU. [--jk]
+	 *
+	 * I used reverse-engineering in DOSEMU. [--jk]
 	 *
 	 * ULTRINIT.EXE:
 	 * 0x230 = 0,2,3
@@ -172,7 +175,14 @@ static int snd_gusextreme_detect(struct snd_gus_card *gus,
 		outb(0, 0x201);
 		outb(gus->gf1.port & 0x010 ? 3 : 1, ES1688P(es1688, INIT1));
 	}
+}
+
+static int snd_gusextreme_detect(struct snd_gus_card *gus,
+				 struct snd_es1688 *es1688)
+{
+	unsigned char d;
 
+	snd_gusextreme_enable_gf1(gus, es1688);
 	udelay(100);
 
 	snd_gf1_i_write8(gus, SNDRV_GF1_GB_RESET, 0);	/* reset GF1 */
@@ -223,16 +233,18 @@ static int snd_gusextreme_probe(struct device *dev, unsigned int n)
 {
 	struct snd_card *card;
 	struct snd_gus_card *gus;
+	struct snd_gusextreme *gusextreme;
 	struct snd_es1688 *es1688;
 	struct snd_opl3 *opl3;
 	int error;
 
 	error = snd_devm_card_new(dev, index[n], id[n], THIS_MODULE,
-				  sizeof(struct snd_es1688), &card);
+				  sizeof(*gusextreme), &card);
 	if (error < 0)
 		return error;
 
-	es1688 = card->private_data;
+	gusextreme = card->private_data;
+	es1688 = &gusextreme->es1688;
 
 	if (mpu_port[n] == SNDRV_AUTO_PORT)
 		mpu_port[n] = 0;
@@ -250,6 +262,7 @@ static int snd_gusextreme_probe(struct device *dev, unsigned int n)
 	error = snd_gusextreme_gus_card_create(card, dev, n, &gus);
 	if (error < 0)
 		return error;
+	gusextreme->gus = gus;
 
 	error = snd_gusextreme_detect(gus, es1688);
 	if (error < 0)
@@ -321,10 +334,36 @@ static int snd_gusextreme_probe(struct device *dev, unsigned int n)
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int snd_gusextreme_suspend(struct device *dev, unsigned int n,
+				  pm_message_t state)
+{
+	struct snd_card *card = dev_get_drvdata(dev);
+	struct snd_gusextreme *gusextreme = card->private_data;
+
+	return snd_gus_suspend(gusextreme->gus);
+}
+
+static int snd_gusextreme_resume(struct device *dev, unsigned int n)
+{
+	struct snd_card *card = dev_get_drvdata(dev);
+	struct snd_gusextreme *gusextreme = card->private_data;
+	int err;
+
+	err = snd_es1688_reset(&gusextreme->es1688);
+	if (err < 0)
+		return err;
+
+	snd_gusextreme_enable_gf1(gusextreme->gus, &gusextreme->es1688);
+	usleep_range(100, 200);
+	return snd_gus_resume(gusextreme->gus);
+}
+#endif
+
 static struct isa_driver snd_gusextreme_driver = {
 	.match		= snd_gusextreme_match,
 	.probe		= snd_gusextreme_probe,
-#if 0	/* FIXME */
+#ifdef CONFIG_PM
 	.suspend	= snd_gusextreme_suspend,
 	.resume		= snd_gusextreme_resume,
 #endif

-- 
2.53.0