[ALSA] virtuoso: monitor external power on D2X

On the Xonar D2X, monitor the GPIO pin that indicates whether external
power is present.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

sound/pci/oxygen/oxygen.h

@@ -66,6 +66,7 @@ struct oxygen {
 	struct snd_pcm_substream *streams[PCM_COUNT];
 	struct snd_kcontrol *controls[CONTROL_COUNT];
 	struct work_struct spdif_input_bits_work;
+	struct work_struct gpio_work;
 	wait_queue_head_t ac97_waitqueue;
 };
 
@@ -88,6 +89,7 @@ struct oxygen_model {
 	void (*update_dac_mute)(struct oxygen *chip);
 	void (*ac97_switch_hook)(struct oxygen *chip, unsigned int codec,
 				 unsigned int reg, int mute);
+	void (*gpio_changed)(struct oxygen *chip);
 	size_t model_data_size;
 	u8 dac_channels;
 	u8 used_channels;

sound/pci/oxygen/oxygen_lib.c

@@ -85,7 +85,7 @@ static irqreturn_t oxygen_interrupt(int dummy, void *dev_id)
 	}
 
 	if (status & OXYGEN_INT_GPIO)
-		;
+		schedule_work(&chip->gpio_work);
 
 	if ((status & OXYGEN_INT_MIDI) && chip->midi)
 		snd_mpu401_uart_interrupt(0, chip->midi->private_data);
@@ -157,6 +157,14 @@ static void oxygen_spdif_input_bits_changed(struct work_struct *work)
 	}
 }
 
+static void oxygen_gpio_changed(struct work_struct *work)
+{
+	struct oxygen *chip = container_of(work, struct oxygen, gpio_work);
+
+	if (chip->model->gpio_changed)
+		chip->model->gpio_changed(chip);
+}
+
 #ifdef CONFIG_PROC_FS
 static void oxygen_proc_read(struct snd_info_entry *entry,
 			     struct snd_info_buffer *buffer)
@@ -413,6 +421,7 @@ int __devinit oxygen_pci_probe(struct pci_dev *pci, int index, char *id,
 	mutex_init(&chip->mutex);
 	INIT_WORK(&chip->spdif_input_bits_work,
 		  oxygen_spdif_input_bits_changed);
+	INIT_WORK(&chip->gpio_work, oxygen_gpio_changed);
 	init_waitqueue_head(&chip->ac97_waitqueue);
 
 	err = pci_enable_device(pci);

sound/pci/oxygen/virtuoso.c

@@ -136,6 +136,11 @@ MODULE_DEVICE_TABLE(pci, xonar_ids);
 /* register 23 */
 #define PCM1796_ID_MASK		0x1f
 
+struct xonar_data {
+	u8 is_d2x;
+	u8 has_power;
+};
+
 static void pcm1796_write(struct oxygen *chip, unsigned int codec,
 			  u8 reg, u8 value)
 {
@@ -153,8 +158,11 @@ static void pcm1796_write(struct oxygen *chip, unsigned int codec,
 
 static void xonar_init(struct oxygen *chip)
 {
+	struct xonar_data *data = chip->model_data;
 	unsigned int i;
 
+	data->is_d2x = chip->pci->subsystem_device == 0x82b7;
+
 	for (i = 0; i < 4; ++i) {
 		pcm1796_write(chip, i, 18, PCM1796_FMT_24_LJUST | PCM1796_ATLD);
 		pcm1796_write(chip, i, 19, PCM1796_FLT_SHARP | PCM1796_ATS_1);
@@ -169,6 +177,15 @@ static void xonar_init(struct oxygen *chip)
 	oxygen_write16_masked(chip, OXYGEN_GPIO_DATA,
 			      GPIO_CS5381_M_SINGLE,
 			      GPIO_CS5381_M_MASK | GPIO_ALT);
+	if (data->is_d2x) {
+		oxygen_clear_bits16(chip, OXYGEN_GPIO_CONTROL,
+				    GPIO_EXT_POWER);
+		oxygen_set_bits16(chip, OXYGEN_GPIO_INTERRUPT_MASK,
+				  GPIO_EXT_POWER);
+		chip->interrupt_mask |= OXYGEN_INT_GPIO;
+		data->has_power = !!(oxygen_read16(chip, OXYGEN_GPIO_DATA)
+				     & GPIO_EXT_POWER);
+	}
 	oxygen_ac97_set_bits(chip, 0, CM9780_JACK, CM9780_FMIC2MIC);
 	oxygen_ac97_clear_bits(chip, 0, CM9780_GPIO_STATUS, GPIO_LINE_MUTE);
 	msleep(300);
@@ -234,6 +251,27 @@ static void set_cs5381_params(struct oxygen *chip,
 			      value, GPIO_CS5381_M_MASK);
 }
 
+static void xonar_gpio_changed(struct oxygen *chip)
+{
+	struct xonar_data *data = chip->model_data;
+	u8 has_power;
+
+	if (!data->is_d2x)
+		return;
+	has_power = !!(oxygen_read16(chip, OXYGEN_GPIO_DATA)
+		       & GPIO_EXT_POWER);
+	if (has_power != data->has_power) {
+		data->has_power = has_power;
+		if (has_power) {
+			snd_printk(KERN_NOTICE "power restored\n");
+		} else {
+			snd_printk(KERN_CRIT
+				   "Hey! Don't unplug the power cable!\n");
+			/* TODO: stop PCMs */
+		}
+	}
+}
+
 static void mute_ac97_ctl(struct oxygen *chip, unsigned int control)
 {
 	unsigned int index = chip->controls[control]->private_value & 0xff;
@@ -360,6 +398,8 @@ static const struct oxygen_model model_xonar = {
 	.update_dac_volume = update_pcm1796_volume,
 	.update_dac_mute = update_pcm1796_mute,
 	.ac97_switch_hook = xonar_ac97_switch_hook,
+	.gpio_changed = xonar_gpio_changed,
+	.model_data_size = sizeof(struct xonar_data),
 	.dac_channels = 8,
 	.used_channels = OXYGEN_CHANNEL_B |
 			 OXYGEN_CHANNEL_C |