1 files changed, 298 insertions, 115 deletions

diff --git a/drivers/iio/magnetometer/mag3110.c b/drivers/iio/magnetometer/mag3110.c
index dad8d57f7402..ff09250a06e7 100644
--- a/drivers/iio/magnetometer/mag3110.c
+++ b/drivers/iio/magnetometer/mag3110.c
@@ -1,17 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * mag3110.c - Support for Freescale MAG3110 magnetometer sensor
  *
  * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
  *
- * This file is subject to the terms and conditions of version 2 of
- * the GNU General Public License.  See the file COPYING in the main
- * directory of this archive for more details.
- *
  * (7-bit I2C slave address 0x0e)
  *
  * TODO: irq, user offset, oversampling, continuous mode
  */
 
+#include <linux/cleanup.h>
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/iio/iio.h>
@@ -20,12 +18,14 @@
 #include <linux/iio/buffer.h>
 #include <linux/iio/triggered_buffer.h>
 #include <linux/delay.h>
+#include <linux/regulator/consumer.h>
 
 #define MAG3110_STATUS 0x00
 #define MAG3110_OUT_X 0x01 /* MSB first */
 #define MAG3110_OUT_Y 0x03
 #define MAG3110_OUT_Z 0x05
 #define MAG3110_WHO_AM_I 0x07
+#define MAG3110_SYSMOD 0x08
 #define MAG3110_OFF_X 0x09 /* MSB first */
 #define MAG3110_OFF_Y 0x0b
 #define MAG3110_OFF_Z 0x0d
@@ -39,6 +39,8 @@
 #define MAG3110_CTRL_DR_SHIFT 5
 #define MAG3110_CTRL_DR_DEFAULT 0
 
+#define MAG3110_SYSMOD_MODE_MASK GENMASK(1, 0)
+
 #define MAG3110_CTRL_TM BIT(1) /* trigger single measurement */
 #define MAG3110_CTRL_AC BIT(0) /* continuous measurements */
 
@@ -52,17 +54,28 @@ struct mag3110_data {
 	struct i2c_client *client;
 	struct mutex lock;
 	u8 ctrl_reg1;
+	int sleep_val;
+	struct regulator *vdd_reg;
+	struct regulator *vddio_reg;
+	/* Ensure natural alignment of timestamp */
+	struct {
+		__be16 channels[3];
+		u8 temperature;
+		aligned_s64 ts;
+	} scan;
 };
 
 static int mag3110_request(struct mag3110_data *data)
 {
 	int ret, tries = 150;
 
-	/* trigger measurement */
-	ret = i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
-		data->ctrl_reg1 | MAG3110_CTRL_TM);
-	if (ret < 0)
-		return ret;
+	if ((data->ctrl_reg1 & MAG3110_CTRL_AC) == 0) {
+		/* trigger measurement */
+		ret = i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
+			data->ctrl_reg1 | MAG3110_CTRL_TM);
+		if (ret < 0)
+			return ret;
+	}
 
 	while (tries-- > 0) {
 		ret = i2c_smbus_read_byte_data(data->client, MAG3110_STATUS);
@@ -71,7 +84,11 @@ static int mag3110_request(struct mag3110_data *data)
 		/* wait for data ready */
 		if ((ret & MAG3110_STATUS_DRDY) == MAG3110_STATUS_DRDY)
 			break;
-		msleep(20);
+
+		if (data->sleep_val <= 20)
+			usleep_range(data->sleep_val * 250, data->sleep_val * 500);
+		else
+			msleep(20);
 	}
 
 	if (tries < 0) {
@@ -86,17 +103,12 @@ static int mag3110_read(struct mag3110_data *data, __be16 buf[3])
 {
 	int ret;
 
-	mutex_lock(&data->lock);
+	guard(mutex)(&data->lock);
 	ret = mag3110_request(data);
-	if (ret < 0) {
-		mutex_unlock(&data->lock);
+	if (ret < 0)
 		return ret;
-	}
-	ret = i2c_smbus_read_i2c_block_data(data->client,
-		MAG3110_OUT_X, 3 * sizeof(__be16), (u8 *) buf);
-	mutex_unlock(&data->lock);
-
-	return ret;
+	return i2c_smbus_read_i2c_block_data(data->client, MAG3110_OUT_X,
+					     3 * sizeof(__be16), (u8 *) buf);
 }
 
 static ssize_t mag3110_show_int_plus_micros(char *buf,
@@ -144,49 +156,157 @@ static int mag3110_get_samp_freq_index(struct mag3110_data *data,
 		val2);
 }
 
+static int mag3110_calculate_sleep(struct mag3110_data *data)
+{
+	int ret, i = data->ctrl_reg1 >> MAG3110_CTRL_DR_SHIFT;
+
+	if (mag3110_samp_freq[i][0] > 0)
+		ret = 1000 / mag3110_samp_freq[i][0];
+	else
+		ret = 1000;
+
+	return ret == 0 ? 1 : ret;
+}
+
+static int mag3110_standby(struct mag3110_data *data)
+{
+	return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
+		data->ctrl_reg1 & ~MAG3110_CTRL_AC);
+}
+
+static int mag3110_wait_standby(struct mag3110_data *data)
+{
+	int ret, tries = 30;
+
+	/*
+	 * Takes up to 1/ODR to come out of active mode into stby
+	 * Longest expected period is 12.5seconds.
+	 * We'll sleep for 500ms between checks
+	 */
+	while (tries-- > 0) {
+		ret = i2c_smbus_read_byte_data(data->client, MAG3110_SYSMOD);
+		if (ret < 0) {
+			dev_err(&data->client->dev, "i2c error\n");
+			return ret;
+		}
+		/* wait for standby */
+		if ((ret & MAG3110_SYSMOD_MODE_MASK) == 0)
+			break;
+
+		msleep_interruptible(500);
+	}
+
+	if (tries < 0) {
+		dev_err(&data->client->dev, "device not entering standby mode\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int mag3110_active(struct mag3110_data *data)
+{
+	return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
+					 data->ctrl_reg1);
+}
+
+/* returns >0 if active, 0 if in standby and <0 on error */
+static int mag3110_is_active(struct mag3110_data *data)
+{
+	int reg;
+
+	reg = i2c_smbus_read_byte_data(data->client, MAG3110_CTRL_REG1);
+	if (reg < 0)
+		return reg;
+
+	return reg & MAG3110_CTRL_AC;
+}
+
+static int mag3110_change_config(struct mag3110_data *data, u8 reg, u8 val)
+{
+	int ret;
+	int is_active;
+
+	guard(mutex)(&data->lock);
+
+	is_active = mag3110_is_active(data);
+	if (is_active < 0)
+		return is_active;
+
+	/* config can only be changed when in standby */
+	if (is_active > 0) {
+		ret = mag3110_standby(data);
+		if (ret < 0)
+			return ret;
+	}
+
+	/*
+	 * After coming out of active we must wait for the part
+	 * to transition to STBY. This can take up to 1 /ODR to occur
+	 */
+	ret = mag3110_wait_standby(data);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_smbus_write_byte_data(data->client, reg, val);
+	if (ret < 0)
+		return ret;
+
+	if (is_active > 0) {
+		ret = mag3110_active(data);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int __mag3110_read_info_raw(struct mag3110_data *data,
+				   struct iio_chan_spec const *chan,
+				   int *val)
+{
+	__be16 buffer[3];
+	int ret;
+
+	switch (chan->type) {
+	case IIO_MAGN: /* in 0.1 uT / LSB */
+		ret = mag3110_read(data, buffer);
+		if (ret < 0)
+			return ret;
+		*val = sign_extend32(be16_to_cpu(buffer[chan->scan_index]),
+				     chan->scan_type.realbits - 1);
+		return IIO_VAL_INT;
+
+	case IIO_TEMP: { /* in 1 C / LSB */
+		guard(mutex)(&data->lock);
+		ret = mag3110_request(data);
+		if (ret < 0)
+			return ret;
+		ret = i2c_smbus_read_byte_data(data->client,
+					       MAG3110_DIE_TEMP);
+		if (ret < 0)
+			return ret;
+		*val = sign_extend32(ret, chan->scan_type.realbits - 1);
+		return IIO_VAL_INT;
+	}
+	default:
+		return -EINVAL;
+	}
+}
+
 static int mag3110_read_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *chan,
 			    int *val, int *val2, long mask)
 {
 	struct mag3110_data *data = iio_priv(indio_dev);
-	__be16 buffer[3];
 	int i, ret;
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
-		ret = iio_device_claim_direct_mode(indio_dev);
-		if (ret)
-			return ret;
-
-		switch (chan->type) {
-		case IIO_MAGN: /* in 0.1 uT / LSB */
-			ret = mag3110_read(data, buffer);
-			if (ret < 0)
-				goto release;
-			*val = sign_extend32(
-				be16_to_cpu(buffer[chan->scan_index]), 15);
-			ret = IIO_VAL_INT;
-			break;
-		case IIO_TEMP: /* in 1 C / LSB */
-			mutex_lock(&data->lock);
-			ret = mag3110_request(data);
-			if (ret < 0) {
-				mutex_unlock(&data->lock);
-				goto release;
-			}
-			ret = i2c_smbus_read_byte_data(data->client,
-				MAG3110_DIE_TEMP);
-			mutex_unlock(&data->lock);
-			if (ret < 0)
-				goto release;
-			*val = sign_extend32(ret, 7);
-			ret = IIO_VAL_INT;
-			break;
-		default:
-			ret = -EINVAL;
-		}
-release:
-		iio_device_release_direct_mode(indio_dev);
+		if (!iio_device_claim_direct(indio_dev))
+			return -EBUSY;
+		ret = __mag3110_read_info_raw(data, chan, val);
+		iio_device_release_direct(indio_dev);
 		return ret;
 
 	case IIO_CHAN_INFO_SCALE:
@@ -217,43 +337,51 @@ release:
 	return -EINVAL;
 }
 
-static int mag3110_write_raw(struct iio_dev *indio_dev,
-			     struct iio_chan_spec const *chan,
-			     int val, int val2, long mask)
+static int __mag3110_write_raw(struct mag3110_data *data,
+			      struct iio_chan_spec const *chan,
+			      int val, int val2, long mask)
 {
-	struct mag3110_data *data = iio_priv(indio_dev);
-	int rate, ret;
-
-	ret = iio_device_claim_direct_mode(indio_dev);
-	if (ret)
-		return ret;
+	int rate;
 
 	switch (mask) {
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		rate = mag3110_get_samp_freq_index(data, val, val2);
-		if (rate < 0) {
-			ret = -EINVAL;
-			break;
-		}
+		if (rate < 0)
+			return -EINVAL;
 
-		data->ctrl_reg1 &= ~MAG3110_CTRL_DR_MASK;
+		data->ctrl_reg1 &= 0xff & ~MAG3110_CTRL_DR_MASK
+					& ~MAG3110_CTRL_AC;
 		data->ctrl_reg1 |= rate << MAG3110_CTRL_DR_SHIFT;
-		ret = i2c_smbus_write_byte_data(data->client,
-			MAG3110_CTRL_REG1, data->ctrl_reg1);
-		break;
+		data->sleep_val = mag3110_calculate_sleep(data);
+		if (data->sleep_val < 40)
+			data->ctrl_reg1 |= MAG3110_CTRL_AC;
+
+		return mag3110_change_config(data, MAG3110_CTRL_REG1,
+					     data->ctrl_reg1);
+
 	case IIO_CHAN_INFO_CALIBBIAS:
-		if (val < -10000 || val > 10000) {
-			ret = -EINVAL;
-			break;
-		}
-		ret = i2c_smbus_write_word_swapped(data->client,
+		if (val < -10000 || val > 10000)
+			return -EINVAL;
+
+		return i2c_smbus_write_word_swapped(data->client,
 			MAG3110_OFF_X + 2 * chan->scan_index, val << 1);
-		break;
 	default:
-		ret = -EINVAL;
-		break;
+		return -EINVAL;
 	}
-	iio_device_release_direct_mode(indio_dev);
+}
+
+static int mag3110_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	struct mag3110_data *data = iio_priv(indio_dev);
+	int ret;
+
+	if (!iio_device_claim_direct(indio_dev))
+		return -EBUSY;
+	ret = __mag3110_write_raw(data, chan, val, val2, mask);
+	iio_device_release_direct(indio_dev);
+
 	return ret;
 }
 
@@ -262,10 +390,9 @@ static irqreturn_t mag3110_trigger_handler(int irq, void *p)
 	struct iio_poll_func *pf = p;
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct mag3110_data *data = iio_priv(indio_dev);
-	u8 buffer[16]; /* 3 16-bit channels + 1 byte temp + padding + ts */
 	int ret;
 
-	ret = mag3110_read(data, (__be16 *) buffer);
+	ret = mag3110_read(data, data->scan.channels);
 	if (ret < 0)
 		goto done;
 
@@ -274,11 +401,11 @@ static irqreturn_t mag3110_trigger_handler(int irq, void *p)
 			MAG3110_DIE_TEMP);
 		if (ret < 0)
 			goto done;
-		buffer[6] = ret;
+		data->scan.temperature = ret;
 	}
 
-	iio_push_to_buffers_with_timestamp(indio_dev, buffer,
-		iio_get_time_ns(indio_dev));
+	iio_push_to_buffers_with_ts(indio_dev, &data->scan, sizeof(data->scan),
+				    iio_get_time_ns(indio_dev));
 
 done:
 	iio_trigger_notify_done(indio_dev->trig);
@@ -333,52 +460,72 @@ static const struct iio_info mag3110_info = {
 	.attrs = &mag3110_group,
 	.read_raw = &mag3110_read_raw,
 	.write_raw = &mag3110_write_raw,
-	.driver_module = THIS_MODULE,
 };
 
 static const unsigned long mag3110_scan_masks[] = {0x7, 0xf, 0};
 
-static int mag3110_standby(struct mag3110_data *data)
-{
-	return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
-		data->ctrl_reg1 & ~MAG3110_CTRL_AC);
-}
-
-static int mag3110_probe(struct i2c_client *client,
-			 const struct i2c_device_id *id)
+static int mag3110_probe(struct i2c_client *client)
 {
+	const struct i2c_device_id *id = i2c_client_get_device_id(client);
 	struct mag3110_data *data;
 	struct iio_dev *indio_dev;
 	int ret;
 
-	ret = i2c_smbus_read_byte_data(client, MAG3110_WHO_AM_I);
-	if (ret < 0)
-		return ret;
-	if (ret != MAG3110_DEVICE_ID)
-		return -ENODEV;
-
 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 	if (!indio_dev)
 		return -ENOMEM;
 
 	data = iio_priv(indio_dev);
+
+	data->vdd_reg = devm_regulator_get(&client->dev, "vdd");
+	if (IS_ERR(data->vdd_reg))
+		return dev_err_probe(&client->dev, PTR_ERR(data->vdd_reg),
+				     "failed to get VDD regulator!\n");
+
+	data->vddio_reg = devm_regulator_get(&client->dev, "vddio");
+	if (IS_ERR(data->vddio_reg))
+		return dev_err_probe(&client->dev, PTR_ERR(data->vddio_reg),
+				     "failed to get VDDIO regulator!\n");
+
+	ret = regulator_enable(data->vdd_reg);
+	if (ret) {
+		dev_err(&client->dev, "failed to enable VDD regulator!\n");
+		return ret;
+	}
+
+	ret = regulator_enable(data->vddio_reg);
+	if (ret) {
+		dev_err(&client->dev, "failed to enable VDDIO regulator!\n");
+		goto disable_regulator_vdd;
+	}
+
+	ret = i2c_smbus_read_byte_data(client, MAG3110_WHO_AM_I);
+	if (ret < 0)
+		goto disable_regulators;
+	if (ret != MAG3110_DEVICE_ID) {
+		ret = -ENODEV;
+		goto disable_regulators;
+	}
+
 	data->client = client;
 	mutex_init(&data->lock);
 
 	i2c_set_clientdata(client, indio_dev);
 	indio_dev->info = &mag3110_info;
 	indio_dev->name = id->name;
-	indio_dev->dev.parent = &client->dev;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->channels = mag3110_channels;
 	indio_dev->num_channels = ARRAY_SIZE(mag3110_channels);
 	indio_dev->available_scan_masks = mag3110_scan_masks;
 
 	data->ctrl_reg1 = MAG3110_CTRL_DR_DEFAULT << MAG3110_CTRL_DR_SHIFT;
-	ret = i2c_smbus_write_byte_data(client, MAG3110_CTRL_REG1,
-		data->ctrl_reg1);
+	data->sleep_val = mag3110_calculate_sleep(data);
+	if (data->sleep_val < 40)
+		data->ctrl_reg1 |= MAG3110_CTRL_AC;
+
+	ret = mag3110_change_config(data, MAG3110_CTRL_REG1, data->ctrl_reg1);
 	if (ret < 0)
-		return ret;
+		goto disable_regulators;
 
 	ret = i2c_smbus_write_byte_data(client, MAG3110_CTRL_REG2,
 		MAG3110_CTRL_AUTO_MRST_EN);
@@ -399,44 +546,80 @@ buffer_cleanup:
 	iio_triggered_buffer_cleanup(indio_dev);
 standby_on_error:
 	mag3110_standby(iio_priv(indio_dev));
+disable_regulators:
+	regulator_disable(data->vddio_reg);
+disable_regulator_vdd:
+	regulator_disable(data->vdd_reg);
+
 	return ret;
 }
 
-static int mag3110_remove(struct i2c_client *client)
+static void mag3110_remove(struct i2c_client *client)
 {
 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct mag3110_data *data = iio_priv(indio_dev);
 
 	iio_device_unregister(indio_dev);
 	iio_triggered_buffer_cleanup(indio_dev);
 	mag3110_standby(iio_priv(indio_dev));
-
-	return 0;
+	regulator_disable(data->vddio_reg);
+	regulator_disable(data->vdd_reg);
 }
 
-#ifdef CONFIG_PM_SLEEP
 static int mag3110_suspend(struct device *dev)
 {
-	return mag3110_standby(iio_priv(i2c_get_clientdata(
+	struct mag3110_data *data = iio_priv(i2c_get_clientdata(
+		to_i2c_client(dev)));
+	int ret;
+
+	ret = mag3110_standby(iio_priv(i2c_get_clientdata(
 		to_i2c_client(dev))));
+	if (ret)
+		return ret;
+
+	ret = regulator_disable(data->vddio_reg);
+	if (ret) {
+		dev_err(dev, "failed to disable VDDIO regulator\n");
+		return ret;
+	}
+
+	ret = regulator_disable(data->vdd_reg);
+	if (ret) {
+		dev_err(dev, "failed to disable VDD regulator\n");
+		return ret;
+	}
+
+	return 0;
 }
 
 static int mag3110_resume(struct device *dev)
 {
 	struct mag3110_data *data = iio_priv(i2c_get_clientdata(
 		to_i2c_client(dev)));
+	int ret;
+
+	ret = regulator_enable(data->vdd_reg);
+	if (ret) {
+		dev_err(dev, "failed to enable VDD regulator\n");
+		return ret;
+	}
+
+	ret = regulator_enable(data->vddio_reg);
+	if (ret) {
+		dev_err(dev, "failed to enable VDDIO regulator\n");
+		regulator_disable(data->vdd_reg);
+		return ret;
+	}
 
 	return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
 		data->ctrl_reg1);
 }
 
-static SIMPLE_DEV_PM_OPS(mag3110_pm_ops, mag3110_suspend, mag3110_resume);
-#define MAG3110_PM_OPS (&mag3110_pm_ops)
-#else
-#define MAG3110_PM_OPS NULL
-#endif
+static DEFINE_SIMPLE_DEV_PM_OPS(mag3110_pm_ops, mag3110_suspend,
+				mag3110_resume);
 
 static const struct i2c_device_id mag3110_id[] = {
-	{ "mag3110", 0 },
+	{ "mag3110" },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, mag3110_id);
@@ -451,7 +634,7 @@ static struct i2c_driver mag3110_driver = {
 	.driver = {
 		.name	= "mag3110",
 		.of_match_table = mag3110_of_match,
-		.pm	= MAG3110_PM_OPS,
+		.pm	= pm_sleep_ptr(&mag3110_pm_ops),
 	},
 	.probe = mag3110_probe,
 	.remove = mag3110_remove,