1 files changed, 204 insertions, 34 deletions

diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 9c5c9ef3f1da..609a2c401b5d 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -32,9 +32,17 @@
 #include <linux/gpio.h>
 #include <linux/of_gpio.h>
 #include <linux/acpi.h>
+#include <linux/regulator/consumer.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#include <linux/iio/magnetometer/ak8975.h>
+
 /*
  * Register definitions, as well as various shifts and masks to get at the
  * individual fields of the registers.
@@ -361,7 +369,6 @@ static const struct ak_def ak_def_array[AK_MAX_TYPE] = {
 struct ak8975_data {
 	struct i2c_client	*client;
 	const struct ak_def	*def;
-	struct attribute_group	attrs;
 	struct mutex		lock;
 	u8			asa[3];
 	long			raw_to_gauss[3];
@@ -370,8 +377,41 @@ struct ak8975_data {
 	wait_queue_head_t	data_ready_queue;
 	unsigned long		flags;
 	u8			cntl_cache;
+	struct iio_mount_matrix orientation;
+	struct regulator	*vdd;
 };
 
+/* Enable attached power regulator if any. */
+static int ak8975_power_on(struct i2c_client *client)
+{
+	const struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct ak8975_data *data = iio_priv(indio_dev);
+	int ret;
+
+	data->vdd = devm_regulator_get(&client->dev, "vdd");
+	if (IS_ERR_OR_NULL(data->vdd)) {
+		ret = PTR_ERR(data->vdd);
+		if (ret == -ENODEV)
+			ret = 0;
+	} else {
+		ret = regulator_enable(data->vdd);
+	}
+
+	if (ret)
+		dev_err(&client->dev, "failed to enable Vdd supply: %d\n", ret);
+	return ret;
+}
+
+/* Disable attached power regulator if any. */
+static void ak8975_power_off(const struct i2c_client *client)
+{
+	const struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	const struct ak8975_data *data = iio_priv(indio_dev);
+
+	if (!IS_ERR_OR_NULL(data->vdd))
+		regulator_disable(data->vdd);
+}
+
 /*
  * Return 0 if the i2c device is the one we expect.
  * return a negative error number otherwise
@@ -462,6 +502,8 @@ static int ak8975_setup_irq(struct ak8975_data *data)
 	int rc;
 	int irq;
 
+	init_waitqueue_head(&data->data_ready_queue);
+	clear_bit(0, &data->flags);
 	if (client->irq)
 		irq = client->irq;
 	else
@@ -477,8 +519,6 @@ static int ak8975_setup_irq(struct ak8975_data *data)
 		return rc;
 	}
 
-	init_waitqueue_head(&data->data_ready_queue);
-	clear_bit(0, &data->flags);
 	data->eoc_irq = irq;
 
 	return rc;
@@ -601,22 +641,15 @@ static int wait_conversion_complete_interrupt(struct ak8975_data *data)
 	return ret > 0 ? 0 : -ETIME;
 }
 
-/*
- * Emits the raw flux value for the x, y, or z axis.
- */
-static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
+static int ak8975_start_read_axis(struct ak8975_data *data,
+				  const struct i2c_client *client)
 {
-	struct ak8975_data *data = iio_priv(indio_dev);
-	struct i2c_client *client = data->client;
-	int ret;
-
-	mutex_lock(&data->lock);
-
 	/* Set up the device for taking a sample. */
-	ret = ak8975_set_mode(data, MODE_ONCE);
+	int ret = ak8975_set_mode(data, MODE_ONCE);
+
 	if (ret < 0) {
 		dev_err(&client->dev, "Error in setting operating mode\n");
-		goto exit;
+		return ret;
 	}
 
 	/* Wait for the conversion to complete. */
@@ -627,7 +660,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
 	else
 		ret = wait_conversion_complete_polled(data);
 	if (ret < 0)
-		goto exit;
+		return ret;
 
 	/* This will be executed only for non-interrupt based waiting case */
 	if (ret & data->def->ctrl_masks[ST1_DRDY]) {
@@ -635,32 +668,45 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
 					       data->def->ctrl_regs[ST2]);
 		if (ret < 0) {
 			dev_err(&client->dev, "Error in reading ST2\n");
-			goto exit;
+			return ret;
 		}
 		if (ret & (data->def->ctrl_masks[ST2_DERR] |
 			   data->def->ctrl_masks[ST2_HOFL])) {
 			dev_err(&client->dev, "ST2 status error 0x%x\n", ret);
-			ret = -EINVAL;
-			goto exit;
+			return -EINVAL;
 		}
 	}
 
-	/* Read the flux value from the appropriate register
-	   (the register is specified in the iio device attributes). */
-	ret = i2c_smbus_read_word_data(client, data->def->data_regs[index]);
-	if (ret < 0) {
-		dev_err(&client->dev, "Read axis data fails\n");
+	return 0;
+}
+
+/* Retrieve raw flux value for one of the x, y, or z axis.  */
+static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
+{
+	struct ak8975_data *data = iio_priv(indio_dev);
+	const struct i2c_client *client = data->client;
+	const struct ak_def *def = data->def;
+	int ret;
+
+	mutex_lock(&data->lock);
+
+	ret = ak8975_start_read_axis(data, client);
+	if (ret)
+		goto exit;
+
+	ret = i2c_smbus_read_word_data(client, def->data_regs[index]);
+	if (ret < 0)
 		goto exit;
-	}
 
 	mutex_unlock(&data->lock);
 
 	/* Clamp to valid range. */
-	*val = clamp_t(s16, ret, -data->def->range, data->def->range);
+	*val = clamp_t(s16, ret, -def->range, def->range);
 	return IIO_VAL_INT;
 
 exit:
 	mutex_unlock(&data->lock);
+	dev_err(&client->dev, "Error in reading axis\n");
 	return ret;
 }
 
@@ -682,6 +728,18 @@ static int ak8975_read_raw(struct iio_dev *indio_dev,
 	return -EINVAL;
 }
 
+static const struct iio_mount_matrix *
+ak8975_get_mount_matrix(const struct iio_dev *indio_dev,
+			const struct iio_chan_spec *chan)
+{
+	return &((struct ak8975_data *)iio_priv(indio_dev))->orientation;
+}
+
+static const struct iio_chan_spec_ext_info ak8975_ext_info[] = {
+	IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, ak8975_get_mount_matrix),
+	{ },
+};
+
 #define AK8975_CHANNEL(axis, index)					\
 	{								\
 		.type = IIO_MAGN,					\
@@ -690,12 +748,23 @@ static int ak8975_read_raw(struct iio_dev *indio_dev,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
 			     BIT(IIO_CHAN_INFO_SCALE),			\
 		.address = index,					\
+		.scan_index = index,					\
+		.scan_type = {						\
+			.sign = 's',					\
+			.realbits = 16,					\
+			.storagebits = 16,				\
+			.endianness = IIO_CPU				\
+		},							\
+		.ext_info = ak8975_ext_info,				\
 	}
 
 static const struct iio_chan_spec ak8975_channels[] = {
 	AK8975_CHANNEL(X, 0), AK8975_CHANNEL(Y, 1), AK8975_CHANNEL(Z, 2),
+	IIO_CHAN_SOFT_TIMESTAMP(3),
 };
 
+static const unsigned long ak8975_scan_masks[] = { 0x7, 0 };
+
 static const struct iio_info ak8975_info = {
 	.read_raw = &ak8975_read_raw,
 	.driver_module = THIS_MODULE,
@@ -724,6 +793,56 @@ static const char *ak8975_match_acpi_device(struct device *dev,
 	return dev_name(dev);
 }
 
+static void ak8975_fill_buffer(struct iio_dev *indio_dev)
+{
+	struct ak8975_data *data = iio_priv(indio_dev);
+	const struct i2c_client *client = data->client;
+	const struct ak_def *def = data->def;
+	int ret;
+	s16 buff[8]; /* 3 x 16 bits axis values + 1 aligned 64 bits timestamp */
+
+	mutex_lock(&data->lock);
+
+	ret = ak8975_start_read_axis(data, client);
+	if (ret)
+		goto unlock;
+
+	/*
+	 * For each axis, read the flux value from the appropriate register
+	 * (the register is specified in the iio device attributes).
+	 */
+	ret = i2c_smbus_read_i2c_block_data_or_emulated(client,
+							def->data_regs[0],
+							3 * sizeof(buff[0]),
+							(u8 *)buff);
+	if (ret < 0)
+		goto unlock;
+
+	mutex_unlock(&data->lock);
+
+	/* Clamp to valid range. */
+	buff[0] = clamp_t(s16, le16_to_cpu(buff[0]), -def->range, def->range);
+	buff[1] = clamp_t(s16, le16_to_cpu(buff[1]), -def->range, def->range);
+	buff[2] = clamp_t(s16, le16_to_cpu(buff[2]), -def->range, def->range);
+
+	iio_push_to_buffers_with_timestamp(indio_dev, buff, iio_get_time_ns());
+	return;
+
+unlock:
+	mutex_unlock(&data->lock);
+	dev_err(&client->dev, "Error in reading axes block\n");
+}
+
+static irqreturn_t ak8975_handle_trigger(int irq, void *p)
+{
+	const struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+
+	ak8975_fill_buffer(indio_dev);
+	iio_trigger_notify_done(indio_dev->trig);
+	return IRQ_HANDLED;
+}
+
 static int ak8975_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
@@ -732,11 +851,13 @@ static int ak8975_probe(struct i2c_client *client,
 	int eoc_gpio;
 	int err;
 	const char *name = NULL;
-	enum asahi_compass_chipset chipset;
+	enum asahi_compass_chipset chipset = AK_MAX_TYPE;
+	const struct ak8975_platform_data *pdata =
+		dev_get_platdata(&client->dev);
 
 	/* Grab and set up the supplied GPIO. */
-	if (client->dev.platform_data)
-		eoc_gpio = *(int *)(client->dev.platform_data);
+	if (pdata)
+		eoc_gpio = pdata->eoc_gpio;
 	else if (client->dev.of_node)
 		eoc_gpio = of_get_gpio(client->dev.of_node, 0);
 	else
@@ -770,13 +891,24 @@ static int ak8975_probe(struct i2c_client *client,
 	data->eoc_gpio = eoc_gpio;
 	data->eoc_irq = 0;
 
+	if (!pdata) {
+		err = of_iio_read_mount_matrix(&client->dev,
+					       "mount-matrix",
+					       &data->orientation);
+		if (err)
+			return err;
+	} else
+		data->orientation = pdata->orientation;
+
 	/* id will be NULL when enumerated via ACPI */
 	if (id) {
 		chipset = (enum asahi_compass_chipset)(id->driver_data);
 		name = id->name;
-	} else if (ACPI_HANDLE(&client->dev))
+	} else if (ACPI_HANDLE(&client->dev)) {
 		name = ak8975_match_acpi_device(&client->dev, &chipset);
-	else
+		if (!name)
+			return -ENODEV;
+	} else
 		return -ENOSYS;
 
 	if (chipset >= AK_MAX_TYPE) {
@@ -786,10 +918,15 @@ static int ak8975_probe(struct i2c_client *client,
 	}
 
 	data->def = &ak_def_array[chipset];
+
+	err = ak8975_power_on(client);
+	if (err)
+		return err;
+
 	err = ak8975_who_i_am(client, data->def->type);
 	if (err < 0) {
 		dev_err(&client->dev, "Unexpected device\n");
-		return err;
+		goto power_off;
 	}
 	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
 
@@ -797,7 +934,7 @@ static int ak8975_probe(struct i2c_client *client,
 	err = ak8975_setup(client);
 	if (err < 0) {
 		dev_err(&client->dev, "%s initialization fails\n", name);
-		return err;
+		goto power_off;
 	}
 
 	mutex_init(&data->lock);
@@ -805,9 +942,41 @@ static int ak8975_probe(struct i2c_client *client,
 	indio_dev->channels = ak8975_channels;
 	indio_dev->num_channels = ARRAY_SIZE(ak8975_channels);
 	indio_dev->info = &ak8975_info;
+	indio_dev->available_scan_masks = ak8975_scan_masks;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->name = name;
-	return devm_iio_device_register(&client->dev, indio_dev);
+
+	err = iio_triggered_buffer_setup(indio_dev, NULL, ak8975_handle_trigger,
+					 NULL);
+	if (err) {
+		dev_err(&client->dev, "triggered buffer setup failed\n");
+		goto power_off;
+	}
+
+	err = iio_device_register(indio_dev);
+	if (err) {
+		dev_err(&client->dev, "device register failed\n");
+		goto cleanup_buffer;
+	}
+
+	return 0;
+
+cleanup_buffer:
+	iio_triggered_buffer_cleanup(indio_dev);
+power_off:
+	ak8975_power_off(client);
+	return err;
+}
+
+static int ak8975_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+	iio_triggered_buffer_cleanup(indio_dev);
+	ak8975_power_off(client);
+
+	return 0;
 }
 
 static const struct i2c_device_id ak8975_id[] = {
@@ -841,6 +1010,7 @@ static struct i2c_driver ak8975_driver = {
 		.acpi_match_table = ACPI_PTR(ak_acpi_match),
 	},
 	.probe		= ak8975_probe,
+	.remove		= ak8975_remove,
 	.id_table	= ak8975_id,
 };
 module_i2c_driver(ak8975_driver);