[PATCH v2 00/13] ad799x cleanup

[PATCH v2 00/13] ad799x cleanup

[Peter Meerwald]

first patch is bug fix (reading/writing of event values, apply shift), 
could be backported to -stable (when the ad799x driver was still in stable)

incorporating comments by Lars-Peter and Jonathan regarding
patch description

Peter Meerwald (13):
  iio:adc:ad799x: Fix reading and writing of event values, apply shift
  iio:adc:ad799x: Fix ad799x_chip_info kerneldoc
  iio:adc:ad799x: Drop I2C access helper functions
  iio:adc:ad799x: Save some lines in ad7997_8_update_scan_mode() exit
    handling
  iio:adc:ad799x: Use BIT() and GENMASK()
  iio:adc:ad799x: Only expose event interface when IRQ is available
  iio:adc:ad799x: Make chan_spec const in ad799x_chip_config struct
  iio:adc:ad799x: Check range when writing event value
  iio:adc:ad799x: Add helper function to read/write config register
  iio:adc:ad799x: Write default config on probe and reset alert status
    on probe
  iio:adc:ad799x: Set conversion channels and rename
    ad7997_8_update_scan_mode()
  iio:adc:ad799x: Return more meaningful event enabled state
  iio:adc:ad799x: Allow to write event config

 drivers/iio/adc/ad799x.c | 510 ++++++++++++++++++++++++++++-------------------
 1 file changed, 307 insertions(+), 203 deletions(-)

-- 
1.9.1

[PATCH v2 01/13] iio:adc:ad799x: Fix reading and writing of event values, apply shift

[Peter Meerwald]

last two bits of ADC and limit values are zero and should not be reported
(ad7993, ad7997); compare with read_raw()

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
---
 drivers/iio/adc/ad799x.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index 39b4cb4..099b830 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -429,7 +429,8 @@ static int ad799x_write_event_value(struct iio_dev *indio_dev,
 
 	mutex_lock(&indio_dev->mlock);
 	ret = ad799x_i2c_write16(st, ad799x_threshold_reg(chan, dir, info),
-		val);
+		(val & RES_MASK(chan->scan_type.realbits))
+			<< chan->scan_type.shift);
 	mutex_unlock(&indio_dev->mlock);
 
 	return ret;
@@ -452,7 +453,8 @@ static int ad799x_read_event_value(struct iio_dev *indio_dev,
 	mutex_unlock(&indio_dev->mlock);
 	if (ret < 0)
 		return ret;
-	*val = valin;
+	*val = (valin >> chan->scan_type.shift) &
+		RES_MASK(chan->scan_type.realbits);
 
 	return IIO_VAL_INT;
 }
-- 
1.9.1

[PATCH v2 02/13] iio:adc:ad799x: Fix ad799x_chip_info kerneldoc

[Peter Meerwald]

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/iio/adc/ad799x.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index 099b830..b250651 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -105,9 +105,8 @@ enum {
  * struct ad799x_chip_info - chip specific information
  * @channel:		channel specification
  * @num_channels:	number of channels
- * @monitor_mode:	whether the chip supports monitor interrupts
  * @default_config:	device default configuration
- * @event_attrs:	pointer to the monitor event attribute group
+ * @info:		pointer to iio_info struct
  */
 struct ad799x_chip_info {
 	struct iio_chan_spec		channel[9];
-- 
1.9.1

[PATCH v2 03/13] iio:adc:ad799x: Drop I2C access helper functions

[Peter Meerwald]

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
---
 drivers/iio/adc/ad799x.c | 119 +++++++++++------------------------------------
 1 file changed, 26 insertions(+), 93 deletions(-)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index b250651..d1ba99b 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -175,65 +175,6 @@ out:
 	return IRQ_HANDLED;
 }
 
-/*
- * ad799x register access by I2C
- */
-static int ad799x_i2c_read16(struct ad799x_state *st, u8 reg, u16 *data)
-{
-	struct i2c_client *client = st->client;
-	int ret = 0;
-
-	ret = i2c_smbus_read_word_swapped(client, reg);
-	if (ret < 0) {
-		dev_err(&client->dev, "I2C read error\n");
-		return ret;
-	}
-
-	*data = (u16)ret;
-
-	return 0;
-}
-
-static int ad799x_i2c_read8(struct ad799x_state *st, u8 reg, u8 *data)
-{
-	struct i2c_client *client = st->client;
-	int ret = 0;
-
-	ret = i2c_smbus_read_byte_data(client, reg);
-	if (ret < 0) {
-		dev_err(&client->dev, "I2C read error\n");
-		return ret;
-	}
-
-	*data = (u8)ret;
-
-	return 0;
-}
-
-static int ad799x_i2c_write16(struct ad799x_state *st, u8 reg, u16 data)
-{
-	struct i2c_client *client = st->client;
-	int ret = 0;
-
-	ret = i2c_smbus_write_word_swapped(client, reg, data);
-	if (ret < 0)
-		dev_err(&client->dev, "I2C write error\n");
-
-	return ret;
-}
-
-static int ad799x_i2c_write8(struct ad799x_state *st, u8 reg, u8 data)
-{
-	struct i2c_client *client = st->client;
-	int ret = 0;
-
-	ret = i2c_smbus_write_byte_data(client, reg, data);
-	if (ret < 0)
-		dev_err(&client->dev, "I2C write error\n");
-
-	return ret;
-}
-
 static int ad7997_8_update_scan_mode(struct iio_dev *indio_dev,
 	const unsigned long *scan_mask)
 {
@@ -249,7 +190,7 @@ static int ad7997_8_update_scan_mode(struct iio_dev *indio_dev,
 	switch (st->id) {
 	case ad7997:
 	case ad7998:
-		return ad799x_i2c_write16(st, AD7998_CONF_REG,
+		return i2c_smbus_write_word_swapped(st->client, AD7998_CONF_REG,
 			st->config | (*scan_mask << AD799X_CHANNEL_SHIFT));
 	default:
 		break;
@@ -260,9 +201,7 @@ static int ad7997_8_update_scan_mode(struct iio_dev *indio_dev,
 
 static int ad799x_scan_direct(struct ad799x_state *st, unsigned ch)
 {
-	u16 rxbuf;
 	u8 cmd;
-	int ret;
 
 	switch (st->id) {
 	case ad7991:
@@ -283,11 +222,7 @@ static int ad799x_scan_direct(struct ad799x_state *st, unsigned ch)
 		return -EINVAL;
 	}
 
-	ret = ad799x_i2c_read16(st, cmd, &rxbuf);
-	if (ret < 0)
-		return ret;
-
-	return rxbuf;
+	return i2c_smbus_read_word_swapped(st->client, cmd);
 }
 
 static int ad799x_read_raw(struct iio_dev *indio_dev,
@@ -332,6 +267,7 @@ static const unsigned int ad7998_frequencies[] = {
 	[AD7998_CYC_TCONF_1024]	= 488,
 	[AD7998_CYC_TCONF_2048]	= 244,
 };
+
 static ssize_t ad799x_read_frequency(struct device *dev,
 					struct device_attribute *attr,
 					char *buf)
@@ -339,15 +275,11 @@ static ssize_t ad799x_read_frequency(struct device *dev,
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ad799x_state *st = iio_priv(indio_dev);
 
-	int ret;
-	u8 val;
-	ret = ad799x_i2c_read8(st, AD7998_CYCLE_TMR_REG, &val);
-	if (ret)
+	int ret = i2c_smbus_read_byte_data(st->client, AD7998_CYCLE_TMR_REG);
+	if (ret < 0)
 		return ret;
 
-	val &= AD7998_CYC_MASK;
-
-	return sprintf(buf, "%u\n", ad7998_frequencies[val]);
+	return sprintf(buf, "%u\n", ad7998_frequencies[ret & AD7998_CYC_MASK]);
 }
 
 static ssize_t ad799x_write_frequency(struct device *dev,
@@ -360,18 +292,17 @@ static ssize_t ad799x_write_frequency(struct device *dev,
 
 	long val;
 	int ret, i;
-	u8 t;
 
 	ret = kstrtol(buf, 10, &val);
 	if (ret)
 		return ret;
 
 	mutex_lock(&indio_dev->mlock);
-	ret = ad799x_i2c_read8(st, AD7998_CYCLE_TMR_REG, &t);
-	if (ret)
+	ret = i2c_smbus_read_byte_data(st->client, AD7998_CYCLE_TMR_REG);
+	if (ret < 0)
 		goto error_ret_mutex;
 	/* Wipe the bits clean */
-	t &= ~AD7998_CYC_MASK;
+	ret &= ~AD7998_CYC_MASK;
 
 	for (i = 0; i < ARRAY_SIZE(ad7998_frequencies); i++)
 		if (val == ad7998_frequencies[i])
@@ -380,13 +311,17 @@ static ssize_t ad799x_write_frequency(struct device *dev,
 		ret = -EINVAL;
 		goto error_ret_mutex;
 	}
-	t |= i;
-	ret = ad799x_i2c_write8(st, AD7998_CYCLE_TMR_REG, t);
+
+	ret = i2c_smbus_write_byte_data(st->client, AD7998_CYCLE_TMR_REG,
+		ret | i);
+	if (ret < 0)
+		goto error_ret_mutex;
+	ret = len;
 
 error_ret_mutex:
 	mutex_unlock(&indio_dev->mlock);
 
-	return ret ? ret : len;
+	return ret;
 }
 
 static int ad799x_read_event_config(struct iio_dev *indio_dev,
@@ -427,7 +362,8 @@ static int ad799x_write_event_value(struct iio_dev *indio_dev,
 	struct ad799x_state *st = iio_priv(indio_dev);
 
 	mutex_lock(&indio_dev->mlock);
-	ret = ad799x_i2c_write16(st, ad799x_threshold_reg(chan, dir, info),
+	ret = i2c_smbus_write_word_swapped(st->client,
+		ad799x_threshold_reg(chan, dir, info),
 		(val & RES_MASK(chan->scan_type.realbits))
 			<< chan->scan_type.shift);
 	mutex_unlock(&indio_dev->mlock);
@@ -444,15 +380,14 @@ static int ad799x_read_event_value(struct iio_dev *indio_dev,
 {
 	int ret;
 	struct ad799x_state *st = iio_priv(indio_dev);
-	u16 valin;
 
 	mutex_lock(&indio_dev->mlock);
-	ret = ad799x_i2c_read16(st, ad799x_threshold_reg(chan, dir, info),
-		&valin);
+	ret = i2c_smbus_read_word_swapped(st->client,
+		ad799x_threshold_reg(chan, dir, info));
 	mutex_unlock(&indio_dev->mlock);
 	if (ret < 0)
 		return ret;
-	*val = (valin >> chan->scan_type.shift) &
+	*val = (ret >> chan->scan_type.shift) &
 		RES_MASK(chan->scan_type.realbits);
 
 	return IIO_VAL_INT;
@@ -462,20 +397,18 @@ static irqreturn_t ad799x_event_handler(int irq, void *private)
 {
 	struct iio_dev *indio_dev = private;
 	struct ad799x_state *st = iio_priv(private);
-	u8 status;
 	int i, ret;
 
-	ret = ad799x_i2c_read8(st, AD7998_ALERT_STAT_REG, &status);
-	if (ret)
+	ret = i2c_smbus_read_byte_data(st->client, AD7998_ALERT_STAT_REG);
+	if (ret <= 0)
 		goto done;
 
-	if (!status)
+	if (i2c_smbus_write_byte_data(st->client, AD7998_ALERT_STAT_REG,
+		AD7998_ALERT_STAT_CLEAR) < 0)
 		goto done;
 
-	ad799x_i2c_write8(st, AD7998_ALERT_STAT_REG, AD7998_ALERT_STAT_CLEAR);
-
 	for (i = 0; i < 8; i++) {
-		if (status & (1 << i))
+		if (ret & (1 << i))
 			iio_push_event(indio_dev,
 				       i & 0x1 ?
 				       IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
-- 
1.9.1

[PATCH v2 04/13] iio:adc:ad799x: Save some lines in ad7997_8_update_scan_mode() exit handling

[Peter Meerwald]

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/iio/adc/ad799x.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index d1ba99b..320e3a3 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -193,10 +193,8 @@ static int ad7997_8_update_scan_mode(struct iio_dev *indio_dev,
 		return i2c_smbus_write_word_swapped(st->client, AD7998_CONF_REG,
 			st->config | (*scan_mask << AD799X_CHANNEL_SHIFT));
 	default:
-		break;
+		return 0;
 	}
-
-	return 0;
 }
 
 static int ad799x_scan_direct(struct ad799x_state *st, unsigned ch)
-- 
1.9.1

[PATCH v2 05/13] iio:adc:ad799x: Use BIT() and GENMASK()

[Peter Meerwald]

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
---
 drivers/iio/adc/ad799x.c | 31 +++++++++++++++----------------
 1 file changed, 15 insertions(+), 16 deletions(-)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index 320e3a3..cc558e6 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -32,6 +32,7 @@
 #include <linux/types.h>
 #include <linux/err.h>
 #include <linux/module.h>
+#include <linux/bitops.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
@@ -41,7 +42,7 @@
 #include <linux/iio/triggered_buffer.h>
 
 #define AD799X_CHANNEL_SHIFT			4
-#define AD799X_STORAGEBITS			16
+
 /*
  * AD7991, AD7995 and AD7999 defines
  */
@@ -55,10 +56,10 @@
  * AD7992, AD7993, AD7994, AD7997 and AD7998 defines
  */
 
-#define AD7998_FLTR				0x08
-#define AD7998_ALERT_EN				0x04
-#define AD7998_BUSY_ALERT			0x02
-#define AD7998_BUSY_ALERT_POL			0x01
+#define AD7998_FLTR				BIT(3)
+#define AD7998_ALERT_EN				BIT(2)
+#define AD7998_BUSY_ALERT			BIT(1)
+#define AD7998_BUSY_ALERT_POL			BIT(0)
 
 #define AD7998_CONV_RES_REG			0x0
 #define AD7998_ALERT_STAT_REG			0x1
@@ -69,7 +70,7 @@
 #define AD7998_DATAHIGH_REG(x)			((x) * 3 + 0x5)
 #define AD7998_HYST_REG(x)			((x) * 3 + 0x6)
 
-#define AD7998_CYC_MASK				0x7
+#define AD7998_CYC_MASK				GENMASK(2, 0)
 #define AD7998_CYC_DIS				0x0
 #define AD7998_CYC_TCONF_32			0x1
 #define AD7998_CYC_TCONF_64			0x2
@@ -85,10 +86,8 @@
  * AD7997 and AD7997 defines
  */
 
-#define AD7997_8_READ_SINGLE			0x80
-#define AD7997_8_READ_SEQUENCE			0x70
-/* TODO: move this into a common header */
-#define RES_MASK(bits)	((1 << (bits)) - 1)
+#define AD7997_8_READ_SINGLE			BIT(7)
+#define AD7997_8_READ_SEQUENCE			(BIT(6) | BIT(5) | BIT(4))
 
 enum {
 	ad7991,
@@ -205,12 +204,12 @@ static int ad799x_scan_direct(struct ad799x_state *st, unsigned ch)
 	case ad7991:
 	case ad7995:
 	case ad7999:
-		cmd = st->config | ((1 << ch) << AD799X_CHANNEL_SHIFT);
+		cmd = st->config | (BIT(ch) << AD799X_CHANNEL_SHIFT);
 		break;
 	case ad7992:
 	case ad7993:
 	case ad7994:
-		cmd = (1 << ch) << AD799X_CHANNEL_SHIFT;
+		cmd = BIT(ch) << AD799X_CHANNEL_SHIFT;
 		break;
 	case ad7997:
 	case ad7998:
@@ -244,7 +243,7 @@ static int ad799x_read_raw(struct iio_dev *indio_dev,
 		if (ret < 0)
 			return ret;
 		*val = (ret >> chan->scan_type.shift) &
-			RES_MASK(chan->scan_type.realbits);
+			GENMASK(chan->scan_type.realbits - 1, 0);
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SCALE:
 		ret = regulator_get_voltage(st->vref);
@@ -362,7 +361,7 @@ static int ad799x_write_event_value(struct iio_dev *indio_dev,
 	mutex_lock(&indio_dev->mlock);
 	ret = i2c_smbus_write_word_swapped(st->client,
 		ad799x_threshold_reg(chan, dir, info),
-		(val & RES_MASK(chan->scan_type.realbits))
+		(val & GENMASK(chan->scan_type.realbits - 1, 0))
 			<< chan->scan_type.shift);
 	mutex_unlock(&indio_dev->mlock);
 
@@ -386,7 +385,7 @@ static int ad799x_read_event_value(struct iio_dev *indio_dev,
 	if (ret < 0)
 		return ret;
 	*val = (ret >> chan->scan_type.shift) &
-		RES_MASK(chan->scan_type.realbits);
+		GENMASK(chan->scan_type.realbits - 1 , 0);
 
 	return IIO_VAL_INT;
 }
@@ -406,7 +405,7 @@ static irqreturn_t ad799x_event_handler(int irq, void *private)
 		goto done;
 
 	for (i = 0; i < 8; i++) {
-		if (ret & (1 << i))
+		if (ret & BIT(i))
 			iio_push_event(indio_dev,
 				       i & 0x1 ?
 				       IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
-- 
1.9.1

[PATCH v2 06/13] iio:adc:ad799x: Only expose event interface when IRQ is available

[Peter Meerwald]

an IRQ is necessary to handle the ALERT condition; without
IRQ, the IIO event interface serves no purpose

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/iio/adc/ad799x.c | 265 ++++++++++++++++++++++++++++++++---------------
 1 file changed, 179 insertions(+), 86 deletions(-)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index cc558e6..e880d17 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -101,22 +101,32 @@ enum {
 };
 
 /**
- * struct ad799x_chip_info - chip specific information
+ * struct ad799x_chip_config - chip specific information
  * @channel:		channel specification
- * @num_channels:	number of channels
  * @default_config:	device default configuration
  * @info:		pointer to iio_info struct
  */
-struct ad799x_chip_info {
+struct ad799x_chip_config {
 	struct iio_chan_spec		channel[9];
-	int				num_channels;
 	u16				default_config;
 	const struct iio_info		*info;
 };
 
+/**
+ * struct ad799x_chip_info - chip specific information
+ * @num_channels:	number of channels
+ * @noirq_config:	device configuration w/o IRQ
+ * @irq_config:		device configuration w/IRQ
+ */
+struct ad799x_chip_info {
+	int				num_channels;
+	const struct ad799x_chip_config	noirq_config;
+	const struct ad799x_chip_config	irq_config;
+};
+
 struct ad799x_state {
 	struct i2c_client		*client;
-	const struct ad799x_chip_info	*chip_info;
+	const struct ad799x_chip_config	*chip_config;
 	struct regulator		*reg;
 	struct regulator		*vref;
 	unsigned			id;
@@ -444,7 +454,13 @@ static const struct iio_info ad7991_info = {
 	.driver_module = THIS_MODULE,
 };
 
-static const struct iio_info ad7993_4_7_8_info = {
+static const struct iio_info ad7993_4_7_8_noirq_info = {
+	.read_raw = &ad799x_read_raw,
+	.driver_module = THIS_MODULE,
+	.update_scan_mode = ad7997_8_update_scan_mode,
+};
+
+static const struct iio_info ad7993_4_7_8_irq_info = {
 	.read_raw = &ad799x_read_raw,
 	.event_attrs = &ad799x_event_attrs_group,
 	.read_event_config = &ad799x_read_event_config,
@@ -499,103 +515,175 @@ static const struct iio_event_spec ad799x_events[] = {
 
 static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
 	[ad7991] = {
-		.channel = {
-			AD799X_CHANNEL(0, 12),
-			AD799X_CHANNEL(1, 12),
-			AD799X_CHANNEL(2, 12),
-			AD799X_CHANNEL(3, 12),
-			IIO_CHAN_SOFT_TIMESTAMP(4),
-		},
 		.num_channels = 5,
-		.info = &ad7991_info,
+		.noirq_config = {
+			.channel = {
+				AD799X_CHANNEL(0, 12),
+				AD799X_CHANNEL(1, 12),
+				AD799X_CHANNEL(2, 12),
+				AD799X_CHANNEL(3, 12),
+				IIO_CHAN_SOFT_TIMESTAMP(4),
+			},
+			.info = &ad7991_info,
+		},
 	},
 	[ad7995] = {
-		.channel = {
-			AD799X_CHANNEL(0, 10),
-			AD799X_CHANNEL(1, 10),
-			AD799X_CHANNEL(2, 10),
-			AD799X_CHANNEL(3, 10),
-			IIO_CHAN_SOFT_TIMESTAMP(4),
-		},
 		.num_channels = 5,
-		.info = &ad7991_info,
+		.noirq_config = {
+			.channel = {
+				AD799X_CHANNEL(0, 10),
+				AD799X_CHANNEL(1, 10),
+				AD799X_CHANNEL(2, 10),
+				AD799X_CHANNEL(3, 10),
+				IIO_CHAN_SOFT_TIMESTAMP(4),
+			},
+			.info = &ad7991_info,
+		},
 	},
 	[ad7999] = {
-		.channel = {
-			AD799X_CHANNEL(0, 8),
-			AD799X_CHANNEL(1, 8),
-			AD799X_CHANNEL(2, 8),
-			AD799X_CHANNEL(3, 8),
-			IIO_CHAN_SOFT_TIMESTAMP(4),
-		},
 		.num_channels = 5,
-		.info = &ad7991_info,
+		.noirq_config = {
+			.channel = {
+				AD799X_CHANNEL(0, 8),
+				AD799X_CHANNEL(1, 8),
+				AD799X_CHANNEL(2, 8),
+				AD799X_CHANNEL(3, 8),
+				IIO_CHAN_SOFT_TIMESTAMP(4),
+			},
+			.info = &ad7991_info,
+		},
 	},
 	[ad7992] = {
-		.channel = {
-			AD799X_CHANNEL_WITH_EVENTS(0, 12),
-			AD799X_CHANNEL_WITH_EVENTS(1, 12),
-			IIO_CHAN_SOFT_TIMESTAMP(3),
-		},
 		.num_channels = 3,
-		.default_config = AD7998_ALERT_EN,
-		.info = &ad7993_4_7_8_info,
+		.noirq_config = {
+			.channel = {
+				AD799X_CHANNEL(0, 12),
+				AD799X_CHANNEL(1, 12),
+				IIO_CHAN_SOFT_TIMESTAMP(3),
+			},
+			.info = &ad7993_4_7_8_noirq_info,
+		},
+		.irq_config = {
+			.channel = {
+				AD799X_CHANNEL_WITH_EVENTS(0, 12),
+				AD799X_CHANNEL_WITH_EVENTS(1, 12),
+				IIO_CHAN_SOFT_TIMESTAMP(3),
+			},
+			.default_config = AD7998_ALERT_EN,
+			.info = &ad7993_4_7_8_irq_info,
+		},
 	},
 	[ad7993] = {
-		.channel = {
-			AD799X_CHANNEL_WITH_EVENTS(0, 10),
-			AD799X_CHANNEL_WITH_EVENTS(1, 10),
-			AD799X_CHANNEL_WITH_EVENTS(2, 10),
-			AD799X_CHANNEL_WITH_EVENTS(3, 10),
-			IIO_CHAN_SOFT_TIMESTAMP(4),
-		},
 		.num_channels = 5,
-		.default_config = AD7998_ALERT_EN,
-		.info = &ad7993_4_7_8_info,
+		.noirq_config = {
+			.channel = {
+				AD799X_CHANNEL(0, 10),
+				AD799X_CHANNEL(1, 10),
+				AD799X_CHANNEL(2, 10),
+				AD799X_CHANNEL(3, 10),
+				IIO_CHAN_SOFT_TIMESTAMP(4),
+			},
+			.info = &ad7993_4_7_8_noirq_info,
+		},
+		.irq_config = {
+			.channel = {
+				AD799X_CHANNEL_WITH_EVENTS(0, 10),
+				AD799X_CHANNEL_WITH_EVENTS(1, 10),
+				AD799X_CHANNEL_WITH_EVENTS(2, 10),
+				AD799X_CHANNEL_WITH_EVENTS(3, 10),
+				IIO_CHAN_SOFT_TIMESTAMP(4),
+			},
+			.default_config = AD7998_ALERT_EN,
+			.info = &ad7993_4_7_8_irq_info,
+		},
 	},
 	[ad7994] = {
-		.channel = {
-			AD799X_CHANNEL_WITH_EVENTS(0, 12),
-			AD799X_CHANNEL_WITH_EVENTS(1, 12),
-			AD799X_CHANNEL_WITH_EVENTS(2, 12),
-			AD799X_CHANNEL_WITH_EVENTS(3, 12),
-			IIO_CHAN_SOFT_TIMESTAMP(4),
-		},
 		.num_channels = 5,
-		.default_config = AD7998_ALERT_EN,
-		.info = &ad7993_4_7_8_info,
+		.noirq_config = {
+			.channel = {
+				AD799X_CHANNEL(0, 12),
+				AD799X_CHANNEL(1, 12),
+				AD799X_CHANNEL(2, 12),
+				AD799X_CHANNEL(3, 12),
+				IIO_CHAN_SOFT_TIMESTAMP(4),
+			},
+			.info = &ad7993_4_7_8_noirq_info,
+		},
+		.irq_config = {
+			.channel = {
+				AD799X_CHANNEL_WITH_EVENTS(0, 12),
+				AD799X_CHANNEL_WITH_EVENTS(1, 12),
+				AD799X_CHANNEL_WITH_EVENTS(2, 12),
+				AD799X_CHANNEL_WITH_EVENTS(3, 12),
+				IIO_CHAN_SOFT_TIMESTAMP(4),
+			},
+			.default_config = AD7998_ALERT_EN,
+			.info = &ad7993_4_7_8_irq_info,
+		},
 	},
 	[ad7997] = {
-		.channel = {
-			AD799X_CHANNEL_WITH_EVENTS(0, 10),
-			AD799X_CHANNEL_WITH_EVENTS(1, 10),
-			AD799X_CHANNEL_WITH_EVENTS(2, 10),
-			AD799X_CHANNEL_WITH_EVENTS(3, 10),
-			AD799X_CHANNEL(4, 10),
-			AD799X_CHANNEL(5, 10),
-			AD799X_CHANNEL(6, 10),
-			AD799X_CHANNEL(7, 10),
-			IIO_CHAN_SOFT_TIMESTAMP(8),
-		},
 		.num_channels = 9,
-		.default_config = AD7998_ALERT_EN,
-		.info = &ad7993_4_7_8_info,
+		.noirq_config = {
+			.channel = {
+				AD799X_CHANNEL(0, 10),
+				AD799X_CHANNEL(1, 10),
+				AD799X_CHANNEL(2, 10),
+				AD799X_CHANNEL(3, 10),
+				AD799X_CHANNEL(4, 10),
+				AD799X_CHANNEL(5, 10),
+				AD799X_CHANNEL(6, 10),
+				AD799X_CHANNEL(7, 10),
+				IIO_CHAN_SOFT_TIMESTAMP(8),
+			},
+			.info = &ad7993_4_7_8_noirq_info,
+		},
+		.irq_config = {
+			.channel = {
+				AD799X_CHANNEL_WITH_EVENTS(0, 10),
+				AD799X_CHANNEL_WITH_EVENTS(1, 10),
+				AD799X_CHANNEL_WITH_EVENTS(2, 10),
+				AD799X_CHANNEL_WITH_EVENTS(3, 10),
+				AD799X_CHANNEL(4, 10),
+				AD799X_CHANNEL(5, 10),
+				AD799X_CHANNEL(6, 10),
+				AD799X_CHANNEL(7, 10),
+				IIO_CHAN_SOFT_TIMESTAMP(8),
+			},
+			.default_config = AD7998_ALERT_EN,
+			.info = &ad7993_4_7_8_irq_info,
+		},
 	},
 	[ad7998] = {
-		.channel = {
-			AD799X_CHANNEL_WITH_EVENTS(0, 12),
-			AD799X_CHANNEL_WITH_EVENTS(1, 12),
-			AD799X_CHANNEL_WITH_EVENTS(2, 12),
-			AD799X_CHANNEL_WITH_EVENTS(3, 12),
-			AD799X_CHANNEL(4, 12),
-			AD799X_CHANNEL(5, 12),
-			AD799X_CHANNEL(6, 12),
-			AD799X_CHANNEL(7, 12),
-			IIO_CHAN_SOFT_TIMESTAMP(8),
-		},
 		.num_channels = 9,
-		.default_config = AD7998_ALERT_EN,
-		.info = &ad7993_4_7_8_info,
+		.noirq_config = {
+			.channel = {
+				AD799X_CHANNEL(0, 12),
+				AD799X_CHANNEL(1, 12),
+				AD799X_CHANNEL(2, 12),
+				AD799X_CHANNEL(3, 12),
+				AD799X_CHANNEL(4, 12),
+				AD799X_CHANNEL(5, 12),
+				AD799X_CHANNEL(6, 12),
+				AD799X_CHANNEL(7, 12),
+				IIO_CHAN_SOFT_TIMESTAMP(8),
+			},
+			.info = &ad7993_4_7_8_noirq_info,
+		},
+		.irq_config = {
+			.channel = {
+				AD799X_CHANNEL_WITH_EVENTS(0, 12),
+				AD799X_CHANNEL_WITH_EVENTS(1, 12),
+				AD799X_CHANNEL_WITH_EVENTS(2, 12),
+				AD799X_CHANNEL_WITH_EVENTS(3, 12),
+				AD799X_CHANNEL(4, 12),
+				AD799X_CHANNEL(5, 12),
+				AD799X_CHANNEL(6, 12),
+				AD799X_CHANNEL(7, 12),
+				IIO_CHAN_SOFT_TIMESTAMP(8),
+			},
+			.default_config = AD7998_ALERT_EN,
+			.info = &ad7993_4_7_8_irq_info,
+		},
 	},
 };
 
@@ -605,6 +693,8 @@ static int ad799x_probe(struct i2c_client *client,
 	int ret;
 	struct ad799x_state *st;
 	struct iio_dev *indio_dev;
+	const struct ad799x_chip_info *chip_info =
+		&ad799x_chip_info_tbl[id->driver_data];
 
 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
 	if (indio_dev == NULL)
@@ -615,8 +705,11 @@ static int ad799x_probe(struct i2c_client *client,
 	i2c_set_clientdata(client, indio_dev);
 
 	st->id = id->driver_data;
-	st->chip_info = &ad799x_chip_info_tbl[st->id];
-	st->config = st->chip_info->default_config;
+	if (client->irq > 0 && chip_info->irq_config.info)
+		st->chip_config = &chip_info->irq_config;
+	else
+		st->chip_config = &chip_info->noirq_config;
+	st->config = st->chip_config->default_config;
 
 	/* TODO: Add pdata options for filtering and bit delay */
 
@@ -639,11 +732,11 @@ static int ad799x_probe(struct i2c_client *client,
 
 	indio_dev->dev.parent = &client->dev;
 	indio_dev->name = id->name;
-	indio_dev->info = st->chip_info->info;
+	indio_dev->info = st->chip_config->info;
 
 	indio_dev->modes = INDIO_DIRECT_MODE;
-	indio_dev->channels = st->chip_info->channel;
-	indio_dev->num_channels = st->chip_info->num_channels;
+	indio_dev->channels = st->chip_config->channel;
+	indio_dev->num_channels = chip_info->num_channels;
 
 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
 		&ad799x_trigger_handler, NULL);
-- 
1.9.1

[PATCH v2 07/13] iio:adc:ad799x: Make chan_spec const in ad799x_chip_config struct

[Peter Meerwald]

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/iio/adc/ad799x.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index e880d17..ae32ea1 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -107,7 +107,7 @@ enum {
  * @info:		pointer to iio_info struct
  */
 struct ad799x_chip_config {
-	struct iio_chan_spec		channel[9];
+	const struct iio_chan_spec	channel[9];
 	u16				default_config;
 	const struct iio_info		*info;
 };
-- 
1.9.1

[PATCH v2 08/13] iio:adc:ad799x: Check range when writing event value

[Peter Meerwald]

event values are 10 (ad7993, ad7997) or 12 bit max.,
check the range on write

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
---
 drivers/iio/adc/ad799x.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index ae32ea1..fbdefcd 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -368,6 +368,9 @@ static int ad799x_write_event_value(struct iio_dev *indio_dev,
 	int ret;
 	struct ad799x_state *st = iio_priv(indio_dev);
 
+	if (val < 0 || val > GENMASK(chan->scan_type.realbits - 1, 0))
+		return -EINVAL;
+
 	mutex_lock(&indio_dev->mlock);
 	ret = i2c_smbus_write_word_swapped(st->client,
 		ad799x_threshold_reg(chan, dir, info),
-- 
1.9.1

[PATCH v2 09/13] iio:adc:ad799x: Add helper function to read/write config register

[Peter Meerwald]

16-bit on ad7997/ad7998, 8-bit elsewhere

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/iio/adc/ad799x.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index fbdefcd..4e7f6b3 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -136,6 +136,30 @@ struct ad799x_state {
 	unsigned int			transfer_size;
 };
 
+static int ad799x_write_config(struct ad799x_state *st, u16 val)
+{
+	switch (st->id) {
+	case ad7997:
+	case ad7998:
+		return i2c_smbus_write_word_swapped(st->client, AD7998_CONF_REG,
+			val);
+	default:
+		return i2c_smbus_write_byte_data(st->client, AD7998_CONF_REG,
+			val);
+	}
+}
+
+static int ad799x_read_config(struct ad799x_state *st)
+{
+	switch (st->id) {
+	case ad7997:
+	case ad7998:
+		return i2c_smbus_read_word_swapped(st->client, AD7998_CONF_REG);
+	default:
+		return i2c_smbus_read_byte_data(st->client, AD7998_CONF_REG);
+	}
+}
+
 /**
  * ad799x_trigger_handler() bh of trigger launched polling to ring buffer
  *
-- 
1.9.1

[PATCH v2 10/13] iio:adc:ad799x: Write default config on probe and reset alert status on probe

[Peter Meerwald]

writing ALERT_EN and BUSY_ALERT to the chip config register clears
pending alerts, BUSY_ALERT is cleared when reading back the register

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/iio/adc/ad799x.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index 4e7f6b3..a5d1a0a 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -596,7 +596,7 @@ static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
 				AD799X_CHANNEL_WITH_EVENTS(1, 12),
 				IIO_CHAN_SOFT_TIMESTAMP(3),
 			},
-			.default_config = AD7998_ALERT_EN,
+			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
 			.info = &ad7993_4_7_8_irq_info,
 		},
 	},
@@ -620,7 +620,7 @@ static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
 				AD799X_CHANNEL_WITH_EVENTS(3, 10),
 				IIO_CHAN_SOFT_TIMESTAMP(4),
 			},
-			.default_config = AD7998_ALERT_EN,
+			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
 			.info = &ad7993_4_7_8_irq_info,
 		},
 	},
@@ -644,7 +644,7 @@ static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
 				AD799X_CHANNEL_WITH_EVENTS(3, 12),
 				IIO_CHAN_SOFT_TIMESTAMP(4),
 			},
-			.default_config = AD7998_ALERT_EN,
+			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
 			.info = &ad7993_4_7_8_irq_info,
 		},
 	},
@@ -676,7 +676,7 @@ static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
 				AD799X_CHANNEL(7, 10),
 				IIO_CHAN_SOFT_TIMESTAMP(8),
 			},
-			.default_config = AD7998_ALERT_EN,
+			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
 			.info = &ad7993_4_7_8_irq_info,
 		},
 	},
@@ -708,7 +708,7 @@ static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
 				AD799X_CHANNEL(7, 12),
 				IIO_CHAN_SOFT_TIMESTAMP(8),
 			},
-			.default_config = AD7998_ALERT_EN,
+			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
 			.info = &ad7993_4_7_8_irq_info,
 		},
 	},
@@ -736,7 +736,6 @@ static int ad799x_probe(struct i2c_client *client,
 		st->chip_config = &chip_info->irq_config;
 	else
 		st->chip_config = &chip_info->noirq_config;
-	st->config = st->chip_config->default_config;
 
 	/* TODO: Add pdata options for filtering and bit delay */
 
@@ -765,6 +764,14 @@ static int ad799x_probe(struct i2c_client *client,
 	indio_dev->channels = st->chip_config->channel;
 	indio_dev->num_channels = chip_info->num_channels;
 
+	ret = ad799x_write_config(st, st->chip_config->default_config);
+	if (ret < 0)
+		goto error_disable_reg;
+	ret = ad799x_read_config(st);
+	if (ret < 0)
+		goto error_disable_reg;
+	st->config = ret;
+
 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
 		&ad799x_trigger_handler, NULL);
 	if (ret)
-- 
1.9.1

[PATCH v2 11/13] iio:adc:ad799x: Set conversion channels and rename ad7997_8_update_scan_mode()

[Peter Meerwald]

rename since function is used by all chips with ALERT pin, not just ad7997/8

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/iio/adc/ad799x.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index a5d1a0a..b9e02be 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -208,7 +208,7 @@ out:
 	return IRQ_HANDLED;
 }
 
-static int ad7997_8_update_scan_mode(struct iio_dev *indio_dev,
+static int ad799x_update_scan_mode(struct iio_dev *indio_dev,
 	const unsigned long *scan_mask)
 {
 	struct ad799x_state *st = iio_priv(indio_dev);
@@ -221,10 +221,14 @@ static int ad7997_8_update_scan_mode(struct iio_dev *indio_dev,
 	st->transfer_size = bitmap_weight(scan_mask, indio_dev->masklength) * 2;
 
 	switch (st->id) {
+	case ad7992:
+	case ad7993:
+	case ad7994:
 	case ad7997:
 	case ad7998:
-		return i2c_smbus_write_word_swapped(st->client, AD7998_CONF_REG,
-			st->config | (*scan_mask << AD799X_CHANNEL_SHIFT));
+		st->config &= ~(GENMASK(7, 0) << AD799X_CHANNEL_SHIFT);
+		st->config |= (*scan_mask << AD799X_CHANNEL_SHIFT);
+		return ad799x_write_config(st, st->config);
 	default:
 		return 0;
 	}
@@ -484,7 +488,7 @@ static const struct iio_info ad7991_info = {
 static const struct iio_info ad7993_4_7_8_noirq_info = {
 	.read_raw = &ad799x_read_raw,
 	.driver_module = THIS_MODULE,
-	.update_scan_mode = ad7997_8_update_scan_mode,
+	.update_scan_mode = ad799x_update_scan_mode,
 };
 
 static const struct iio_info ad7993_4_7_8_irq_info = {
@@ -494,7 +498,7 @@ static const struct iio_info ad7993_4_7_8_irq_info = {
 	.read_event_value = &ad799x_read_event_value,
 	.write_event_value = &ad799x_write_event_value,
 	.driver_module = THIS_MODULE,
-	.update_scan_mode = ad7997_8_update_scan_mode,
+	.update_scan_mode = ad799x_update_scan_mode,
 };
 
 static const struct iio_event_spec ad799x_events[] = {
-- 
1.9.1

[PATCH v2 12/13] iio:adc:ad799x: Return more meaningful event enabled state

[Peter Meerwald]

only report an event as enabled if it actually is enabled

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
---
 drivers/iio/adc/ad799x.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index b9e02be..8b9c939 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -364,7 +364,15 @@ static int ad799x_read_event_config(struct iio_dev *indio_dev,
 				    enum iio_event_type type,
 				    enum iio_event_direction dir)
 {
-	return 1;
+	struct ad799x_state *st = iio_priv(indio_dev);
+
+	if (!(st->config & AD7998_ALERT_EN))
+		return 0;
+
+	if ((st->config >> AD799X_CHANNEL_SHIFT) & BIT(chan->scan_index))
+		return 1;
+
+	return 0;
 }
 
 static unsigned int ad799x_threshold_reg(const struct iio_chan_spec *chan,
-- 
1.9.1

[PATCH v2 13/13] iio:adc:ad799x: Allow to write event config

[Peter Meerwald]

allow to enable events

previously, events were always reported as enabled, but actually only
implicitly enabled when updating the buffer scan mode

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
---
 drivers/iio/adc/ad799x.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index 8b9c939..4048700 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -375,6 +375,39 @@ static int ad799x_read_event_config(struct iio_dev *indio_dev,
 	return 0;
 }
 
+static int ad799x_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)
+{
+	struct ad799x_state *st = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&indio_dev->mlock);
+	if (iio_buffer_enabled(indio_dev)) {
+		ret = -EBUSY;
+		goto done;
+	}
+
+	if (state)
+		st->config |= BIT(chan->scan_index) << AD799X_CHANNEL_SHIFT;
+	else
+		st->config &= ~(BIT(chan->scan_index) << AD799X_CHANNEL_SHIFT);
+
+	if (st->config >> AD799X_CHANNEL_SHIFT)
+		st->config |= AD7998_ALERT_EN;
+	else
+		st->config &= ~AD7998_ALERT_EN;
+
+	ret = ad799x_write_config(st, st->config);
+
+done:
+	mutex_unlock(&indio_dev->mlock);
+
+	return ret;
+}
+
 static unsigned int ad799x_threshold_reg(const struct iio_chan_spec *chan,
 					 enum iio_event_direction dir,
 					 enum iio_event_info info)
@@ -503,6 +536,7 @@ static const struct iio_info ad7993_4_7_8_irq_info = {
 	.read_raw = &ad799x_read_raw,
 	.event_attrs = &ad799x_event_attrs_group,
 	.read_event_config = &ad799x_read_event_config,
+	.write_event_config = &ad799x_write_event_config,
 	.read_event_value = &ad799x_read_event_value,
 	.write_event_value = &ad799x_write_event_value,
 	.driver_module = THIS_MODULE,
-- 
1.9.1

Re: [PATCH v2 05/13] iio:adc:ad799x: Use BIT() and GENMASK()

[Lars-Peter Clausen]

On 06/07/2014 05:31 PM, Peter Meerwald wrote:
> Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>

Acked-by: Lars-Peter Clausen <lars@metafoo.de>

Thanks.

Re: [PATCH v2 01/13] iio:adc:ad799x: Fix reading and writing of event values, apply shift

[Lars-Peter Clausen]

On 06/07/2014 05:31 PM, Peter Meerwald wrote:
> last two bits of ADC and limit values are zero and should not be reported
> (ad7993, ad7997); compare with read_raw()
>
> Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
> ---
>   drivers/iio/adc/ad799x.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
> index 39b4cb4..099b830 100644
> --- a/drivers/iio/adc/ad799x.c
> +++ b/drivers/iio/adc/ad799x.c
> @@ -429,7 +429,8 @@ static int ad799x_write_event_value(struct iio_dev *indio_dev,
>
>   	mutex_lock(&indio_dev->mlock);
>   	ret = ad799x_i2c_write16(st, ad799x_threshold_reg(chan, dir, info),
> -		val);
> +		(val & RES_MASK(chan->scan_type.realbits))
> +			<< chan->scan_type.shift);

Rather than applying a mask to the written value and cutting off the upper 
bits, I'd prefer to have patch 8 (iio:adc:ad799x: Check range when writing 
event value) squashed into this.

Thanks,
- Lars