1 files changed, 148 insertions, 105 deletions

diff --git a/drivers/staging/iio/cdc/ad7150.c b/drivers/staging/iio/cdc/ad7150.c
index f8183c540d5c..bfb80e211742 100644
--- a/drivers/staging/iio/cdc/ad7150.c
+++ b/drivers/staging/iio/cdc/ad7150.c
@@ -11,6 +11,7 @@
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/i2c.h>
+#include <linux/irq.h>
 #include <linux/module.h>
 
 #include <linux/iio/iio.h>
@@ -60,8 +61,6 @@ enum {
 /**
  * struct ad7150_chip_info - instance specific chip data
  * @client: i2c client for this device
- * @current_event: device always has one type of event enabled.
- *	This element stores the event code of the current one.
  * @threshold: thresholds for simple capacitance value events
  * @thresh_sensitivity: threshold for simple capacitance offset
  *	from 'average' value.
@@ -70,21 +69,23 @@ enum {
  *	value jumps to current value.  Note made up of two fields,
  *      3:0 are for timeout receding - applies if below lower threshold
  *      7:4 are for timeout approaching - applies if above upper threshold
- * @old_state: store state from previous event, allowing confirmation
- *	of new condition.
- * @conversion_mode: the current conversion mode.
  * @state_lock: ensure consistent state of this structure wrt the
  *	hardware.
+ * @interrupts: one or two interrupt numbers depending on device type.
+ * @int_enabled: is a given interrupt currently enabled.
+ * @type: threshold type
+ * @dir: threshold direction
  */
 struct ad7150_chip_info {
 	struct i2c_client *client;
-	u64 current_event;
 	u16 threshold[2][2];
 	u8 thresh_sensitivity[2][2];
 	u8 thresh_timeout[2][2];
-	int old_state;
-	char *conversion_mode;
 	struct mutex state_lock;
+	int interrupts[2];
+	bool int_enabled[2];
+	enum iio_event_type type;
+	enum iio_event_direction dir;
 };
 
 /*
@@ -158,8 +159,8 @@ static int ad7150_read_event_config(struct iio_dev *indio_dev,
 	switch (type) {
 	case IIO_EV_TYPE_THRESH_ADAPTIVE:
 		if (dir == IIO_EV_DIR_RISING)
-			return !thrfixed && (threshtype == 0x3);
-		return !thrfixed && (threshtype == 0x2);
+			return !thrfixed && (threshtype == 0x1);
+		return !thrfixed && (threshtype == 0x0);
 	case IIO_EV_TYPE_THRESH:
 		if (dir == IIO_EV_DIR_RISING)
 			return thrfixed && (threshtype == 0x1);
@@ -179,11 +180,9 @@ static int ad7150_write_event_params(struct iio_dev *indio_dev,
 {
 	struct ad7150_chip_info *chip = iio_priv(indio_dev);
 	int rising = (dir == IIO_EV_DIR_RISING);
-	u64 event_code;
 
-	event_code = IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE, chan, type, dir);
-
-	if (event_code != chip->current_event)
+	/* Only update value live, if parameter is in use */
+	if ((type != chip->type) || (dir != chip->dir))
 		return 0;
 
 	switch (type) {
@@ -231,52 +230,91 @@ static int ad7150_write_event_config(struct iio_dev *indio_dev,
 	int ret;
 	struct ad7150_chip_info *chip = iio_priv(indio_dev);
 	int rising = (dir == IIO_EV_DIR_RISING);
-	u64 event_code;
-
-	/* Something must always be turned on */
-	if (!state)
-		return -EINVAL;
 
-	event_code = IIO_UNMOD_EVENT_CODE(chan->type, chan->channel, type, dir);
-	if (event_code == chip->current_event)
+	/*
+	 * There is only a single shared control and no on chip
+	 * interrupt disables for the two interrupt lines.
+	 * So, enabling will switch the events configured to enable
+	 * whatever was most recently requested and if necessary enable_irq()
+	 * the interrupt and any disable will disable_irq() for that
+	 * channels interrupt.
+	 */
+	if (!state) {
+		if ((chip->int_enabled[chan->channel]) &&
+		    (type == chip->type) && (dir == chip->dir)) {
+			disable_irq(chip->interrupts[chan->channel]);
+			chip->int_enabled[chan->channel] = false;
+		}
 		return 0;
+	}
+
 	mutex_lock(&chip->state_lock);
-	ret = i2c_smbus_read_byte_data(chip->client, AD7150_CFG);
-	if (ret < 0)
-		goto error_ret;
+	if ((type != chip->type) || (dir != chip->dir)) {
 
-	cfg = ret & ~((0x03 << 5) | BIT(7));
+		/*
+		 * Need to temporarily disable both interrupts if
+		 * enabled - this is to avoid races around changing
+		 * config and thresholds.
+		 * Note enable/disable_irq() are reference counted so
+		 * no need to check if already enabled.
+		 */
+		disable_irq(chip->interrupts[0]);
+		disable_irq(chip->interrupts[1]);
 
-	switch (type) {
-	case IIO_EV_TYPE_THRESH_ADAPTIVE:
-		adaptive = 1;
-		if (rising)
-			thresh_type = 0x3;
-		else
-			thresh_type = 0x2;
-		break;
-	case IIO_EV_TYPE_THRESH:
-		adaptive = 0;
-		if (rising)
-			thresh_type = 0x1;
-		else
-			thresh_type = 0x0;
-		break;
-	default:
-		ret = -EINVAL;
-		goto error_ret;
-	}
+		ret = i2c_smbus_read_byte_data(chip->client, AD7150_CFG);
+		if (ret < 0)
+			goto error_ret;
 
-	cfg |= (!adaptive << 7) | (thresh_type << 5);
+		cfg = ret & ~((0x03 << 5) | BIT(7));
 
-	ret = i2c_smbus_write_byte_data(chip->client, AD7150_CFG, cfg);
-	if (ret < 0)
-		goto error_ret;
+		switch (type) {
+		case IIO_EV_TYPE_THRESH_ADAPTIVE:
+			adaptive = 1;
+			if (rising)
+				thresh_type = 0x1;
+			else
+				thresh_type = 0x0;
+			break;
+		case IIO_EV_TYPE_THRESH:
+			adaptive = 0;
+			if (rising)
+				thresh_type = 0x1;
+			else
+				thresh_type = 0x0;
+			break;
+		default:
+			ret = -EINVAL;
+			goto error_ret;
+		}
 
-	chip->current_event = event_code;
+		cfg |= (!adaptive << 7) | (thresh_type << 5);
+
+		ret = i2c_smbus_write_byte_data(chip->client, AD7150_CFG, cfg);
+		if (ret < 0)
+			goto error_ret;
+
+		/*
+		 * There is a potential race condition here, but not easy
+		 * to close given we can't disable the interrupt at the
+		 * chip side of things. Rely on the status bit.
+		 */
+		chip->type = type;
+		chip->dir = dir;
+
+		/* update control attributes */
+		ret = ad7150_write_event_params(indio_dev, chan->channel, type,
+						dir);
+		if (ret)
+			goto error_ret;
+		/* reenable any irq's we disabled whilst changing mode */
+		enable_irq(chip->interrupts[0]);
+		enable_irq(chip->interrupts[1]);
+	}
+	if (!chip->int_enabled[chan->channel]) {
+		enable_irq(chip->interrupts[chan->channel]);
+		chip->int_enabled[chan->channel] = true;
+	}
 
-	/* update control attributes */
-	ret = ad7150_write_event_params(indio_dev, chan->channel, type, dir);
 error_ret:
 	mutex_unlock(&chip->state_lock);
 
@@ -434,59 +472,39 @@ static const struct iio_chan_spec ad7151_channels_no_irq[] = {
 	AD7150_CAPACITANCE_CHAN_NO_IRQ(0),
 };
 
-static irqreturn_t ad7150_event_handler(int irq, void *private)
+static irqreturn_t __ad7150_event_handler(void *private, u8 status_mask,
+					  int channel)
 {
 	struct iio_dev *indio_dev = private;
 	struct ad7150_chip_info *chip = iio_priv(indio_dev);
-	u8 int_status;
 	s64 timestamp = iio_get_time_ns(indio_dev);
-	int ret;
+	int int_status;
 
-	ret = i2c_smbus_read_byte_data(chip->client, AD7150_STATUS);
-	if (ret < 0)
+	int_status = i2c_smbus_read_byte_data(chip->client, AD7150_STATUS);
+	if (int_status < 0)
 		return IRQ_HANDLED;
 
-	int_status = ret;
-
-	if ((int_status & AD7150_STATUS_OUT1) &&
-	    !(chip->old_state & AD7150_STATUS_OUT1))
-		iio_push_event(indio_dev,
-			       IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE,
-						    0,
-						    IIO_EV_TYPE_THRESH,
-						    IIO_EV_DIR_RISING),
-				timestamp);
-	else if ((!(int_status & AD7150_STATUS_OUT1)) &&
-		 (chip->old_state & AD7150_STATUS_OUT1))
-		iio_push_event(indio_dev,
-			       IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE,
-						    0,
-						    IIO_EV_TYPE_THRESH,
-						    IIO_EV_DIR_FALLING),
-			       timestamp);
-
-	if ((int_status & AD7150_STATUS_OUT2) &&
-	    !(chip->old_state & AD7150_STATUS_OUT2))
-		iio_push_event(indio_dev,
-			       IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE,
-						    1,
-						    IIO_EV_TYPE_THRESH,
-						    IIO_EV_DIR_RISING),
-			       timestamp);
-	else if ((!(int_status & AD7150_STATUS_OUT2)) &&
-		 (chip->old_state & AD7150_STATUS_OUT2))
-		iio_push_event(indio_dev,
-			       IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE,
-						    1,
-						    IIO_EV_TYPE_THRESH,
-						    IIO_EV_DIR_FALLING),
-			       timestamp);
-	/* store the status to avoid repushing same events */
-	chip->old_state = int_status;
+	if (!(int_status & status_mask))
+		return IRQ_HANDLED;
+
+	iio_push_event(indio_dev,
+		       IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE, channel,
+					    chip->type, chip->dir),
+		       timestamp);
 
 	return IRQ_HANDLED;
 }
 
+static irqreturn_t ad7150_event_handler_ch1(int irq, void *private)
+{
+	return __ad7150_event_handler(private, AD7150_STATUS_OUT1, 0);
+}
+
+static irqreturn_t ad7150_event_handler_ch2(int irq, void *private)
+{
+	return __ad7150_event_handler(private, AD7150_STATUS_OUT2, 1);
+}
+
 static IIO_CONST_ATTR(in_capacitance_thresh_adaptive_timeout_available,
 		      "[0 0.01 0.15]");
 
@@ -533,12 +551,44 @@ static int ad7150_probe(struct i2c_client *client,
 
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
-	if (client->irq) {
+	chip->interrupts[0] = fwnode_irq_get(dev_fwnode(&client->dev), 0);
+	if (chip->interrupts[0] < 0)
+		return chip->interrupts[0];
+	if (id->driver_data == AD7150) {
+		chip->interrupts[1] = fwnode_irq_get(dev_fwnode(&client->dev), 1);
+		if (chip->interrupts[1] < 0)
+			return chip->interrupts[1];
+	}
+	if (chip->interrupts[0] &&
+	    (id->driver_data == AD7151 || chip->interrupts[1])) {
+		irq_set_status_flags(chip->interrupts[0], IRQ_NOAUTOEN);
+		ret = devm_request_threaded_irq(&client->dev,
+						chip->interrupts[0],
+						NULL,
+						&ad7150_event_handler_ch1,
+						IRQF_TRIGGER_RISING |
+						IRQF_ONESHOT,
+						"ad7150_irq1",
+						indio_dev);
+		if (ret)
+			return ret;
+
 		indio_dev->info = &ad7150_info;
 		switch (id->driver_data) {
 		case AD7150:
 			indio_dev->channels = ad7150_channels;
 			indio_dev->num_channels = ARRAY_SIZE(ad7150_channels);
+			irq_set_status_flags(chip->interrupts[1], IRQ_NOAUTOEN);
+			ret = devm_request_threaded_irq(&client->dev,
+							chip->interrupts[1],
+							NULL,
+							&ad7150_event_handler_ch2,
+							IRQF_TRIGGER_RISING |
+							IRQF_ONESHOT,
+							"ad7150_irq2",
+							indio_dev);
+			if (ret)
+				return ret;
 			break;
 		case AD7151:
 			indio_dev->channels = ad7151_channels;
@@ -548,25 +598,18 @@ static int ad7150_probe(struct i2c_client *client,
 			return -EINVAL;
 		}
 
-		ret = devm_request_threaded_irq(&client->dev, client->irq,
-						NULL,
-						&ad7150_event_handler,
-						IRQF_TRIGGER_RISING |
-						IRQF_ONESHOT,
-						"ad7150_irq1",
-						indio_dev);
-		if (ret)
-			return ret;
 	} else {
 		indio_dev->info = &ad7150_info_no_irq;
 		switch (id->driver_data) {
 		case AD7150:
 			indio_dev->channels = ad7150_channels_no_irq;
-			indio_dev->num_channels = ARRAY_SIZE(ad7150_channels_no_irq);
+			indio_dev->num_channels =
+				ARRAY_SIZE(ad7150_channels_no_irq);
 			break;
 		case AD7151:
 			indio_dev->channels = ad7151_channels_no_irq;
-			indio_dev->num_channels = ARRAY_SIZE(ad7151_channels_no_irq);
+			indio_dev->num_channels =
+				ARRAY_SIZE(ad7151_channels_no_irq);
 			break;
 		default:
 			return -EINVAL;