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path: root/drivers/iio/adc/ad799x.c
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Diffstat (limited to 'drivers/iio/adc/ad799x.c')
-rw-r--r--drivers/iio/adc/ad799x.c130
1 files changed, 83 insertions, 47 deletions
diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index 18bf8386d50a..108bb22162ef 100644
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -28,6 +28,7 @@
#include <linux/types.h>
#include <linux/err.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/bitops.h>
#include <linux/iio/iio.h>
@@ -113,11 +114,13 @@ struct ad799x_chip_config {
* @num_channels: number of channels
* @noirq_config: device configuration w/o IRQ
* @irq_config: device configuration w/IRQ
+ * @has_vref: device supports external reference voltage
*/
struct ad799x_chip_info {
int num_channels;
const struct ad799x_chip_config noirq_config;
const struct ad799x_chip_config irq_config;
+ bool has_vref;
};
struct ad799x_state {
@@ -125,7 +128,9 @@ struct ad799x_state {
const struct ad799x_chip_config *chip_config;
struct regulator *reg;
struct regulator *vref;
- unsigned id;
+ /* lock to protect against multiple access to the device */
+ struct mutex lock;
+ unsigned int id;
u16 config;
u8 *rx_buf;
@@ -234,7 +239,8 @@ static int ad799x_update_scan_mode(struct iio_dev *indio_dev,
if (!st->rx_buf)
return -ENOMEM;
- st->transfer_size = bitmap_weight(scan_mask, indio_dev->masklength) * 2;
+ st->transfer_size = bitmap_weight(scan_mask,
+ iio_get_masklength(indio_dev)) * 2;
switch (st->id) {
case ad7992:
@@ -250,7 +256,7 @@ static int ad799x_update_scan_mode(struct iio_dev *indio_dev,
}
}
-static int ad799x_scan_direct(struct ad799x_state *st, unsigned ch)
+static int ad799x_scan_direct(struct ad799x_state *st, unsigned int ch)
{
u8 cmd;
@@ -287,11 +293,12 @@ static int ad799x_read_raw(struct iio_dev *indio_dev,
switch (m) {
case IIO_CHAN_INFO_RAW:
- ret = iio_device_claim_direct_mode(indio_dev);
- if (ret)
- return ret;
+ if (!iio_device_claim_direct(indio_dev))
+ return -EBUSY;
+ mutex_lock(&st->lock);
ret = ad799x_scan_direct(st, chan->scan_index);
- iio_device_release_direct_mode(indio_dev);
+ mutex_unlock(&st->lock);
+ iio_device_release_direct(indio_dev);
if (ret < 0)
return ret;
@@ -299,7 +306,11 @@ static int ad799x_read_raw(struct iio_dev *indio_dev,
GENMASK(chan->scan_type.realbits - 1, 0);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
- ret = regulator_get_voltage(st->vref);
+ if (st->vref)
+ ret = regulator_get_voltage(st->vref);
+ else
+ ret = regulator_get_voltage(st->reg);
+
if (ret < 0)
return ret;
*val = ret / 1000;
@@ -326,6 +337,7 @@ static ssize_t ad799x_read_frequency(struct device *dev,
struct ad799x_state *st = iio_priv(indio_dev);
int ret = i2c_smbus_read_byte_data(st->client, AD7998_CYCLE_TMR_REG);
+
if (ret < 0)
return ret;
@@ -347,7 +359,8 @@ static ssize_t ad799x_write_frequency(struct device *dev,
if (ret)
return ret;
- mutex_lock(&indio_dev->mlock);
+ mutex_lock(&st->lock);
+
ret = i2c_smbus_read_byte_data(st->client, AD7998_CYCLE_TMR_REG);
if (ret < 0)
goto error_ret_mutex;
@@ -369,7 +382,7 @@ static ssize_t ad799x_write_frequency(struct device *dev,
ret = len;
error_ret_mutex:
- mutex_unlock(&indio_dev->mlock);
+ mutex_unlock(&st->lock);
return ret;
}
@@ -394,14 +407,15 @@ 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)
+ bool state)
{
struct ad799x_state *st = iio_priv(indio_dev);
int ret;
- ret = iio_device_claim_direct_mode(indio_dev);
- if (ret)
- return ret;
+ if (!iio_device_claim_direct(indio_dev))
+ return -EBUSY;
+
+ mutex_lock(&st->lock);
if (state)
st->config |= BIT(chan->scan_index) << AD799X_CHANNEL_SHIFT;
@@ -414,7 +428,8 @@ static int ad799x_write_event_config(struct iio_dev *indio_dev,
st->config &= ~AD7998_ALERT_EN;
ret = ad799x_write_config(st, st->config);
- iio_device_release_direct_mode(indio_dev);
+ mutex_unlock(&st->lock);
+ iio_device_release_direct(indio_dev);
return ret;
}
@@ -450,11 +465,9 @@ static int ad799x_write_event_value(struct iio_dev *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),
val << chan->scan_type.shift);
- mutex_unlock(&indio_dev->mlock);
return ret;
}
@@ -469,10 +482,8 @@ static int ad799x_read_event_value(struct iio_dev *indio_dev,
int ret;
struct ad799x_state *st = iio_priv(indio_dev);
- mutex_lock(&indio_dev->mlock);
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 = (ret >> chan->scan_type.shift) &
@@ -514,7 +525,7 @@ done:
return IRQ_HANDLED;
}
-static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
+static IIO_DEV_ATTR_SAMP_FREQ(0644,
ad799x_read_frequency,
ad799x_write_frequency);
static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("15625 7812 3906 1953 976 488 244 0");
@@ -595,6 +606,7 @@ static const struct iio_event_spec ad799x_events[] = {
static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
[ad7991] = {
.num_channels = 5,
+ .has_vref = true,
.noirq_config = {
.channel = {
AD799X_CHANNEL(0, 12),
@@ -608,6 +620,7 @@ static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
},
[ad7995] = {
.num_channels = 5,
+ .has_vref = true,
.noirq_config = {
.channel = {
AD799X_CHANNEL(0, 10),
@@ -621,6 +634,7 @@ static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
},
[ad7999] = {
.num_channels = 5,
+ .has_vref = true,
.noirq_config = {
.channel = {
AD799X_CHANNEL(0, 8),
@@ -678,6 +692,7 @@ static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
},
[ad7994] = {
.num_channels = 5,
+ .has_vref = true,
.noirq_config = {
.channel = {
AD799X_CHANNEL(0, 12),
@@ -766,10 +781,11 @@ static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
},
};
-static int ad799x_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
+static int ad799x_probe(struct i2c_client *client)
{
+ const struct i2c_device_id *id = i2c_client_get_device_id(client);
int ret;
+ int extra_config = 0;
struct ad799x_state *st;
struct iio_dev *indio_dev;
const struct ad799x_chip_info *chip_info =
@@ -797,14 +813,26 @@ static int ad799x_probe(struct i2c_client *client,
ret = regulator_enable(st->reg);
if (ret)
return ret;
- st->vref = devm_regulator_get(&client->dev, "vref");
- if (IS_ERR(st->vref)) {
- ret = PTR_ERR(st->vref);
- goto error_disable_reg;
+
+ /* check if an external reference is supplied */
+ if (chip_info->has_vref) {
+ st->vref = devm_regulator_get_optional(&client->dev, "vref");
+ ret = PTR_ERR_OR_ZERO(st->vref);
+ if (ret) {
+ if (ret != -ENODEV)
+ goto error_disable_reg;
+ st->vref = NULL;
+ dev_info(&client->dev, "Using VCC reference voltage\n");
+ }
+
+ if (st->vref) {
+ dev_info(&client->dev, "Using external reference voltage\n");
+ extra_config |= AD7991_REF_SEL;
+ ret = regulator_enable(st->vref);
+ if (ret)
+ goto error_disable_reg;
+ }
}
- ret = regulator_enable(st->vref);
- if (ret)
- goto error_disable_reg;
st->client = client;
@@ -815,7 +843,7 @@ 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_update_config(st, st->chip_config->default_config);
+ ret = ad799x_update_config(st, st->chip_config->default_config | extra_config);
if (ret)
goto error_disable_vref;
@@ -836,6 +864,9 @@ static int ad799x_probe(struct i2c_client *client,
if (ret)
goto error_cleanup_ring;
}
+
+ mutex_init(&st->lock);
+
ret = iio_device_register(indio_dev);
if (ret)
goto error_cleanup_ring;
@@ -845,14 +876,15 @@ static int ad799x_probe(struct i2c_client *client,
error_cleanup_ring:
iio_triggered_buffer_cleanup(indio_dev);
error_disable_vref:
- regulator_disable(st->vref);
+ if (st->vref)
+ regulator_disable(st->vref);
error_disable_reg:
regulator_disable(st->reg);
return ret;
}
-static int ad799x_remove(struct i2c_client *client)
+static void ad799x_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct ad799x_state *st = iio_priv(indio_dev);
@@ -860,25 +892,25 @@ static int ad799x_remove(struct i2c_client *client)
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
- regulator_disable(st->vref);
+ if (st->vref)
+ regulator_disable(st->vref);
regulator_disable(st->reg);
kfree(st->rx_buf);
-
- return 0;
}
-static int __maybe_unused ad799x_suspend(struct device *dev)
+static int ad799x_suspend(struct device *dev)
{
struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
struct ad799x_state *st = iio_priv(indio_dev);
- regulator_disable(st->vref);
+ if (st->vref)
+ regulator_disable(st->vref);
regulator_disable(st->reg);
return 0;
}
-static int __maybe_unused ad799x_resume(struct device *dev)
+static int ad799x_resume(struct device *dev)
{
struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
struct ad799x_state *st = iio_priv(indio_dev);
@@ -889,17 +921,21 @@ static int __maybe_unused ad799x_resume(struct device *dev)
dev_err(dev, "Unable to enable vcc regulator\n");
return ret;
}
- ret = regulator_enable(st->vref);
- if (ret) {
- regulator_disable(st->reg);
- dev_err(dev, "Unable to enable vref regulator\n");
- return ret;
+
+ if (st->vref) {
+ ret = regulator_enable(st->vref);
+ if (ret) {
+ regulator_disable(st->reg);
+ dev_err(dev, "Unable to enable vref regulator\n");
+ return ret;
+ }
}
/* resync config */
ret = ad799x_update_config(st, st->config);
if (ret) {
- regulator_disable(st->vref);
+ if (st->vref)
+ regulator_disable(st->vref);
regulator_disable(st->reg);
return ret;
}
@@ -907,7 +943,7 @@ static int __maybe_unused ad799x_resume(struct device *dev)
return 0;
}
-static SIMPLE_DEV_PM_OPS(ad799x_pm_ops, ad799x_suspend, ad799x_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(ad799x_pm_ops, ad799x_suspend, ad799x_resume);
static const struct i2c_device_id ad799x_id[] = {
{ "ad7991", ad7991 },
@@ -918,7 +954,7 @@ static const struct i2c_device_id ad799x_id[] = {
{ "ad7994", ad7994 },
{ "ad7997", ad7997 },
{ "ad7998", ad7998 },
- {}
+ { }
};
MODULE_DEVICE_TABLE(i2c, ad799x_id);
@@ -926,7 +962,7 @@ MODULE_DEVICE_TABLE(i2c, ad799x_id);
static struct i2c_driver ad799x_driver = {
.driver = {
.name = "ad799x",
- .pm = &ad799x_pm_ops,
+ .pm = pm_sleep_ptr(&ad799x_pm_ops),
},
.probe = ad799x_probe,
.remove = ad799x_remove,
generated by cgit (git 2.34.1) at 2025-12-25 04:08:37 +0000