1 files changed, 107 insertions, 159 deletions

diff --git a/drivers/iio/adc/max1363.c b/drivers/iio/adc/max1363.c
index 7c2a98b8c3a9..e8d731bc34e0 100644
--- a/drivers/iio/adc/max1363.c
+++ b/drivers/iio/adc/max1363.c
@@ -13,6 +13,7 @@
   */
 
 #include <linux/interrupt.h>
+#include <linux/cleanup.h>
 #include <linux/device.h>
 #include <linux/kernel.h>
 #include <linux/sysfs.h>
@@ -24,6 +25,7 @@
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
 #include <linux/property.h>
+#include <linux/unaligned.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
@@ -159,6 +161,7 @@ struct max1363_chip_info {
  * @vref_uv:		Actual (external or internal) reference voltage
  * @send:		function used to send data to the chip
  * @recv:		function used to receive data from the chip
+ * @data:		buffer to store channel data and timestamp
  */
 struct max1363_state {
 	struct i2c_client		*client;
@@ -184,6 +187,10 @@ struct max1363_state {
 						const char *buf, int count);
 	int				(*recv)(const struct i2c_client *client,
 						char *buf, int count);
+	struct {
+		u8 buf[MAX1363_MAX_CHANNELS * 2];
+		aligned_s64 ts;
+	} data;
 };
 
 #define MAX1363_MODE_SINGLE(_num, _mask) {				\
@@ -357,62 +364,55 @@ static int max1363_read_single_chan(struct iio_dev *indio_dev,
 				    int *val,
 				    long m)
 {
-	int ret = 0;
-	s32 data;
-	u8 rxbuf[2];
-	struct max1363_state *st = iio_priv(indio_dev);
-	struct i2c_client *client = st->client;
-
-	ret = iio_device_claim_direct_mode(indio_dev);
-	if (ret)
-		return ret;
-	mutex_lock(&st->lock);
-
-	/*
-	 * If monitor mode is enabled, the method for reading a single
-	 * channel will have to be rather different and has not yet
-	 * been implemented.
-	 *
-	 * Also, cannot read directly if buffered capture enabled.
-	 */
-	if (st->monitor_on) {
-		ret = -EBUSY;
-		goto error_ret;
-	}
-
-	/* Check to see if current scan mode is correct */
-	if (st->current_mode != &max1363_mode_table[chan->address]) {
-		/* Update scan mode if needed */
-		st->current_mode = &max1363_mode_table[chan->address];
-		ret = max1363_set_scan_mode(st);
-		if (ret < 0)
-			goto error_ret;
-	}
-	if (st->chip_info->bits != 8) {
-		/* Get reading */
-		data = st->recv(client, rxbuf, 2);
-		if (data < 0) {
-			ret = data;
-			goto error_ret;
+	iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
+		s32 data;
+		u8 rxbuf[2];
+		struct max1363_state *st = iio_priv(indio_dev);
+		struct i2c_client *client = st->client;
+
+		guard(mutex)(&st->lock);
+
+		/*
+		 * If monitor mode is enabled, the method for reading a single
+		 * channel will have to be rather different and has not yet
+		 * been implemented.
+		 *
+		 * Also, cannot read directly if buffered capture enabled.
+		 */
+		if (st->monitor_on)
+			return -EBUSY;
+
+		/* Check to see if current scan mode is correct */
+		if (st->current_mode != &max1363_mode_table[chan->address]) {
+			int ret;
+
+			/* Update scan mode if needed */
+			st->current_mode = &max1363_mode_table[chan->address];
+			ret = max1363_set_scan_mode(st);
+			if (ret < 0)
+				return ret;
 		}
-		data = (rxbuf[1] | rxbuf[0] << 8) &
-		  ((1 << st->chip_info->bits) - 1);
-	} else {
-		/* Get reading */
-		data = st->recv(client, rxbuf, 1);
-		if (data < 0) {
-			ret = data;
-			goto error_ret;
+		if (st->chip_info->bits != 8) {
+			/* Get reading */
+			data = st->recv(client, rxbuf, 2);
+			if (data < 0)
+				return data;
+
+			data = get_unaligned_be16(rxbuf) &
+				((1 << st->chip_info->bits) - 1);
+		} else {
+			/* Get reading */
+			data = st->recv(client, rxbuf, 1);
+			if (data < 0)
+				return data;
+
+			data = rxbuf[0];
 		}
-		data = rxbuf[0];
-	}
-	*val = data;
-
-error_ret:
-	mutex_unlock(&st->lock);
-	iio_device_release_direct_mode(indio_dev);
-	return ret;
+		*val = data;
 
+		return 0;
+	}
+	unreachable();
 }
 
 static int max1363_read_raw(struct iio_dev *indio_dev,
@@ -710,9 +710,8 @@ static ssize_t max1363_monitor_store_freq(struct device *dev,
 	if (!found)
 		return -EINVAL;
 
-	mutex_lock(&st->lock);
-	st->monitor_speed = i;
-	mutex_unlock(&st->lock);
+	scoped_guard(mutex, &st->lock)
+		st->monitor_speed = i;
 
 	return 0;
 }
@@ -815,19 +814,17 @@ static int max1363_read_event_config(struct iio_dev *indio_dev,
 	int val;
 	int number = chan->channel;
 
-	mutex_lock(&st->lock);
+	guard(mutex)(&st->lock);
 	if (dir == IIO_EV_DIR_FALLING)
 		val = (1 << number) & st->mask_low;
 	else
 		val = (1 << number) & st->mask_high;
-	mutex_unlock(&st->lock);
 
 	return val;
 }
 
 static int max1363_monitor_mode_update(struct max1363_state *st, int enabled)
 {
-	u8 *tx_buf;
 	int ret, i = 3, j;
 	unsigned long numelements;
 	int len;
@@ -859,11 +856,10 @@ static int max1363_monitor_mode_update(struct max1363_state *st, int enabled)
 	}
 	numelements = bitmap_weight(modemask, MAX1363_MAX_CHANNELS);
 	len = 3 * numelements + 3;
-	tx_buf = kmalloc(len, GFP_KERNEL);
-	if (!tx_buf) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
+	u8 *tx_buf __free(kfree) = kmalloc(len, GFP_KERNEL);
+	if (!tx_buf)
+		return -ENOMEM;
+
 	tx_buf[0] = st->configbyte;
 	tx_buf[1] = st->setupbyte;
 	tx_buf[2] = (st->monitor_speed << 1);
@@ -902,11 +898,9 @@ static int max1363_monitor_mode_update(struct max1363_state *st, int enabled)
 
 	ret = st->send(st->client, tx_buf, len);
 	if (ret < 0)
-		goto error_ret;
-	if (ret != len) {
-		ret = -EIO;
-		goto error_ret;
-	}
+		return ret;
+	if (ret != len)
+		return -EIO;
 
 	/*
 	 * Now that we hopefully have sensible thresholds in place it is
@@ -919,18 +913,13 @@ static int max1363_monitor_mode_update(struct max1363_state *st, int enabled)
 	tx_buf[1] = MAX1363_MON_INT_ENABLE | (st->monitor_speed << 1) | 0xF0;
 	ret = st->send(st->client, tx_buf, 2);
 	if (ret < 0)
-		goto error_ret;
-	if (ret != 2) {
-		ret = -EIO;
-		goto error_ret;
-	}
-	ret = 0;
-	st->monitor_on = true;
-error_ret:
+		return ret;
+	if (ret != 2)
+		return -EIO;
 
-	kfree(tx_buf);
+	st->monitor_on = true;
 
-	return ret;
+	return 0;
 }
 
 /*
@@ -960,48 +949,44 @@ error_ret:
 
 static int max1363_write_event_config(struct iio_dev *indio_dev,
 	const struct iio_chan_spec *chan, enum iio_event_type type,
-	enum iio_event_direction dir, int state)
+	enum iio_event_direction dir, bool state)
 {
-	int ret = 0;
 	struct max1363_state *st = iio_priv(indio_dev);
-	u16 unifiedmask;
-	int number = chan->channel;
 
-	ret = iio_device_claim_direct_mode(indio_dev);
-	if (ret)
-		return ret;
-	mutex_lock(&st->lock);
-
-	unifiedmask = st->mask_low | st->mask_high;
-	if (dir == IIO_EV_DIR_FALLING) {
-
-		if (state == 0)
-			st->mask_low &= ~(1 << number);
-		else {
-			ret = __max1363_check_event_mask((1 << number),
-							 unifiedmask);
-			if (ret)
-				goto error_ret;
-			st->mask_low |= (1 << number);
-		}
-	} else {
-		if (state == 0)
-			st->mask_high &= ~(1 << number);
-		else {
-			ret = __max1363_check_event_mask((1 << number),
-							 unifiedmask);
-			if (ret)
-				goto error_ret;
-			st->mask_high |= (1 << number);
+	iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
+		int number = chan->channel;
+		u16 unifiedmask;
+		int ret;
+
+		guard(mutex)(&st->lock);
+
+		unifiedmask = st->mask_low | st->mask_high;
+		if (dir == IIO_EV_DIR_FALLING) {
+
+			if (state == 0)
+				st->mask_low &= ~(1 << number);
+			else {
+				ret = __max1363_check_event_mask((1 << number),
+								 unifiedmask);
+				if (ret)
+					return ret;
+				st->mask_low |= (1 << number);
+			}
+		} else {
+			if (state == 0)
+				st->mask_high &= ~(1 << number);
+			else {
+				ret = __max1363_check_event_mask((1 << number),
+								 unifiedmask);
+				if (ret)
+					return ret;
+				st->mask_high |= (1 << number);
+			}
 		}
 	}
-
 	max1363_monitor_mode_update(st, !!(st->mask_high | st->mask_low));
-error_ret:
-	mutex_unlock(&st->lock);
-	iio_device_release_direct_mode(indio_dev);
 
-	return ret;
+	return 0;
 }
 
 /*
@@ -1482,22 +1467,10 @@ static irqreturn_t max1363_trigger_handler(int irq, void *p)
 	struct iio_poll_func *pf = p;
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct max1363_state *st = iio_priv(indio_dev);
-	__u8 *rxbuf;
 	int b_sent;
-	size_t d_size;
 	unsigned long numvals = bitmap_weight(st->current_mode->modemask,
 					      MAX1363_MAX_CHANNELS);
 
-	/* Ensure the timestamp is 8 byte aligned */
-	if (st->chip_info->bits != 8)
-		d_size = numvals*2;
-	else
-		d_size = numvals;
-	if (indio_dev->scan_timestamp) {
-		d_size += sizeof(s64);
-		if (d_size % sizeof(s64))
-			d_size += sizeof(s64) - (d_size % sizeof(s64));
-	}
 	/* Monitor mode prevents reading. Whilst not currently implemented
 	 * might as well have this test in here in the meantime as it does
 	 * no harm.
@@ -1505,21 +1478,16 @@ static irqreturn_t max1363_trigger_handler(int irq, void *p)
 	if (numvals == 0)
 		goto done;
 
-	rxbuf = kmalloc(d_size,	GFP_KERNEL);
-	if (rxbuf == NULL)
-		goto done;
 	if (st->chip_info->bits != 8)
-		b_sent = st->recv(st->client, rxbuf, numvals * 2);
+		b_sent = st->recv(st->client, st->data.buf, numvals * 2);
 	else
-		b_sent = st->recv(st->client, rxbuf, numvals);
+		b_sent = st->recv(st->client, st->data.buf, numvals);
 	if (b_sent < 0)
-		goto done_free;
+		goto done;
 
-	iio_push_to_buffers_with_timestamp(indio_dev, rxbuf,
+	iio_push_to_buffers_with_timestamp(indio_dev, &st->data,
 					   iio_get_time_ns(indio_dev));
 
-done_free:
-	kfree(rxbuf);
 done:
 	iio_trigger_notify_done(indio_dev->trig);
 
@@ -1574,18 +1542,12 @@ static const struct of_device_id max1363_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, max1363_of_match);
 
-static void max1363_reg_disable(void *reg)
-{
-	regulator_disable(reg);
-}
-
 static int max1363_probe(struct i2c_client *client)
 {
 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
 	int ret;
 	struct max1363_state *st;
 	struct iio_dev *indio_dev;
-	struct regulator *vref;
 
 	indio_dev = devm_iio_device_alloc(&client->dev,
 					  sizeof(struct max1363_state));
@@ -1602,26 +1564,12 @@ static int max1363_probe(struct i2c_client *client)
 	st->chip_info = i2c_get_match_data(client);
 	st->client = client;
 
-	st->vref_uv = st->chip_info->int_vref_mv * 1000;
-	vref = devm_regulator_get_optional(&client->dev, "vref");
-	if (!IS_ERR(vref)) {
-		int vref_uv;
-
-		ret = regulator_enable(vref);
-		if (ret)
-			return ret;
-
-		ret = devm_add_action_or_reset(&client->dev, max1363_reg_disable, vref);
-		if (ret)
-			return ret;
+	ret = devm_regulator_get_enable_read_voltage(&client->dev, "vref");
+	if (ret < 0 && ret != -ENODEV)
+		return ret;
 
-		st->vref = vref;
-		vref_uv = regulator_get_voltage(vref);
-		if (vref_uv <= 0)
-			return -EINVAL;
 
-		st->vref_uv = vref_uv;
-	}
+	st->vref_uv = ret == -ENODEV ? st->chip_info->int_vref_mv * 1000 : ret;
 
 	if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 		st->send = i2c_master_send;