ASoC: Initial WM8962 IRQ support

Provide an initial hookup for interrupts on the WM8962. Currently we simply
report error status via log messages if an IRQ is provided for the device.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>

include/sound/wm8962.h

@@ -17,6 +17,8 @@
 struct wm8962_pdata {
 	u32 gpio_init[WM8962_MAX_GPIO];
 
+	bool irq_active_low;
+
 	bool spk_mono;   /* Speaker outputs tied together as mono */
 };
 

sound/soc/codecs/wm8962.c

@@ -1461,6 +1461,29 @@ static struct snd_soc_dai_driver wm8962_dai = {
 	.symmetric_rates = 1,
 };
 
+static irqreturn_t wm8962_irq(int irq, void *data)
+{
+	struct snd_soc_codec *codec = data;
+	int mask;
+	int active;
+
+	mask = snd_soc_read(codec, WM8962_INTERRUPT_STATUS_2);
+
+	active = snd_soc_read(codec, WM8962_INTERRUPT_STATUS_2);
+	active &= ~mask;
+
+	if (active & WM8962_FIFOS_ERR_EINT)
+		dev_err(codec->dev, "FIFO error\n");
+
+	if (active & WM8962_TEMP_SHUT_EINT)
+		dev_crit(codec->dev, "Thermal shutdown\n");
+
+	/* Acknowledge the interrupts */
+	snd_soc_write(codec, WM8962_INTERRUPT_STATUS_2, active);
+
+	return IRQ_HANDLED;
+}
+
 #ifdef CONFIG_PM
 static int wm8962_resume(struct snd_soc_codec *codec)
 {
@@ -1632,7 +1655,9 @@ static int wm8962_probe(struct snd_soc_codec *codec)
 	int ret;
 	struct wm8962_priv *wm8962 = snd_soc_codec_get_drvdata(codec);
 	struct wm8962_pdata *pdata = dev_get_platdata(codec->dev);
-	int i;
+	struct i2c_client *i2c = container_of(codec->dev, struct i2c_client,
+					      dev);
+	int i, trigger, irq_pol;
 
 	wm8962->codec = codec;
 
@@ -1748,6 +1773,34 @@ static int wm8962_probe(struct snd_soc_codec *codec)
 
 	wm8962_init_beep(codec);
 
+	if (i2c->irq) {
+		if (pdata && pdata->irq_active_low) {
+			trigger = IRQF_TRIGGER_LOW;
+			irq_pol = WM8962_IRQ_POL;
+		} else {
+			trigger = IRQF_TRIGGER_HIGH;
+			irq_pol = 0;
+		}
+
+		snd_soc_update_bits(codec, WM8962_INTERRUPT_CONTROL,
+				    WM8962_IRQ_POL, irq_pol);
+
+		ret = request_threaded_irq(i2c->irq, NULL, wm8962_irq,
+					   trigger | IRQF_ONESHOT,
+					   "wm8962", codec);
+		if (ret != 0) {
+			dev_err(codec->dev, "Failed to request IRQ %d: %d\n",
+				i2c->irq, ret);
+			/* Non-fatal */
+		} else {
+			/* Enable error reporting IRQs by default */
+			snd_soc_update_bits(codec,
+					    WM8962_INTERRUPT_STATUS_2_MASK,
+					    WM8962_TEMP_SHUT_EINT |
+					    WM8962_FIFOS_ERR_EINT, 0);
+		}
+	}
+
 	return 0;
 
 err_enable:
@@ -1762,8 +1815,13 @@ static int wm8962_probe(struct snd_soc_codec *codec)
 static int wm8962_remove(struct snd_soc_codec *codec)
 {
 	struct wm8962_priv *wm8962 = snd_soc_codec_get_drvdata(codec);
+	struct i2c_client *i2c = container_of(codec->dev, struct i2c_client,
+					      dev);
 	int i;
 
+	if (i2c->irq)
+		free_irq(i2c->irq, codec);
+
 	wm8962_free_beep(codec);
 	for (i = 0; i < ARRAY_SIZE(wm8962->supplies); i++)
 		regulator_unregister_notifier(wm8962->supplies[i].consumer,