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path: root/drivers/iio/adc/ti-adc081c.c
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Diffstat (limited to 'drivers/iio/adc/ti-adc081c.c')
-rw-r--r--drivers/iio/adc/ti-adc081c.c118
1 files changed, 106 insertions, 12 deletions
diff --git a/drivers/iio/adc/ti-adc081c.c b/drivers/iio/adc/ti-adc081c.c
index ecbc12138..9fd032d9f 100644
--- a/drivers/iio/adc/ti-adc081c.c
+++ b/drivers/iio/adc/ti-adc081c.c
@@ -1,9 +1,21 @@
/*
+ * TI ADC081C/ADC101C/ADC121C 8/10/12-bit ADC driver
+ *
* Copyright (C) 2012 Avionic Design GmbH
+ * Copyright (C) 2016 Intel
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
+ *
+ * Datasheets:
+ * http://www.ti.com/lit/ds/symlink/adc081c021.pdf
+ * http://www.ti.com/lit/ds/symlink/adc101c021.pdf
+ * http://www.ti.com/lit/ds/symlink/adc121c021.pdf
+ *
+ * The devices have a very similar interface and differ mostly in the number of
+ * bits handled. For the 8-bit and 10-bit models the least-significant 4 or 2
+ * bits of value registers are reserved.
*/
#include <linux/err.h>
@@ -12,11 +24,17 @@
#include <linux/of.h>
#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
#include <linux/regulator/consumer.h>
struct adc081c {
struct i2c_client *i2c;
struct regulator *ref;
+
+ /* 8, 10 or 12 */
+ int bits;
};
#define REG_CONV_RES 0x00
@@ -34,7 +52,7 @@ static int adc081c_read_raw(struct iio_dev *iio,
if (err < 0)
return err;
- *value = (err >> 4) & 0xff;
+ *value = (err & 0xFFF) >> (12 - adc->bits);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
@@ -43,7 +61,7 @@ static int adc081c_read_raw(struct iio_dev *iio,
return err;
*value = err / 1000;
- *shift = 8;
+ *shift = adc->bits;
return IIO_VAL_FRACTIONAL_LOG2;
@@ -54,10 +72,53 @@ static int adc081c_read_raw(struct iio_dev *iio,
return -EINVAL;
}
-static const struct iio_chan_spec adc081c_channel = {
- .type = IIO_VOLTAGE,
- .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+#define ADCxx1C_CHAN(_bits) { \
+ .type = IIO_VOLTAGE, \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = (_bits), \
+ .storagebits = 16, \
+ .shift = 12 - (_bits), \
+ .endianness = IIO_CPU, \
+ }, \
+}
+
+#define DEFINE_ADCxx1C_CHANNELS(_name, _bits) \
+ static const struct iio_chan_spec _name ## _channels[] = { \
+ ADCxx1C_CHAN((_bits)), \
+ IIO_CHAN_SOFT_TIMESTAMP(1), \
+ }; \
+
+#define ADC081C_NUM_CHANNELS 2
+
+struct adcxx1c_model {
+ const struct iio_chan_spec* channels;
+ int bits;
+};
+
+#define ADCxx1C_MODEL(_name, _bits) \
+ { \
+ .channels = _name ## _channels, \
+ .bits = (_bits), \
+ }
+
+DEFINE_ADCxx1C_CHANNELS(adc081c, 8);
+DEFINE_ADCxx1C_CHANNELS(adc101c, 10);
+DEFINE_ADCxx1C_CHANNELS(adc121c, 12);
+
+/* Model ids are indexes in _models array */
+enum adcxx1c_model_id {
+ ADC081C = 0,
+ ADC101C = 1,
+ ADC121C = 2,
+};
+
+static struct adcxx1c_model adcxx1c_models[] = {
+ ADCxx1C_MODEL(adc081c, 8),
+ ADCxx1C_MODEL(adc101c, 10),
+ ADCxx1C_MODEL(adc121c, 12),
};
static const struct iio_info adc081c_info = {
@@ -65,11 +126,30 @@ static const struct iio_info adc081c_info = {
.driver_module = THIS_MODULE,
};
+static irqreturn_t adc081c_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct adc081c *data = iio_priv(indio_dev);
+ u16 buf[8]; /* 2 bytes data + 6 bytes padding + 8 bytes timestamp */
+ int ret;
+
+ ret = i2c_smbus_read_word_swapped(data->i2c, REG_CONV_RES);
+ if (ret < 0)
+ goto out;
+ buf[0] = ret;
+ iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns());
+out:
+ iio_trigger_notify_done(indio_dev->trig);
+ return IRQ_HANDLED;
+}
+
static int adc081c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct iio_dev *iio;
struct adc081c *adc;
+ struct adcxx1c_model *model = &adcxx1c_models[id->driver_data];
int err;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
@@ -81,6 +161,7 @@ static int adc081c_probe(struct i2c_client *client,
adc = iio_priv(iio);
adc->i2c = client;
+ adc->bits = model->bits;
adc->ref = devm_regulator_get(&client->dev, "vref");
if (IS_ERR(adc->ref))
@@ -95,18 +176,26 @@ static int adc081c_probe(struct i2c_client *client,
iio->modes = INDIO_DIRECT_MODE;
iio->info = &adc081c_info;
- iio->channels = &adc081c_channel;
- iio->num_channels = 1;
+ iio->channels = model->channels;
+ iio->num_channels = ADC081C_NUM_CHANNELS;
+
+ err = iio_triggered_buffer_setup(iio, NULL, adc081c_trigger_handler, NULL);
+ if (err < 0) {
+ dev_err(&client->dev, "iio triggered buffer setup failed\n");
+ goto err_regulator_disable;
+ }
err = iio_device_register(iio);
if (err < 0)
- goto regulator_disable;
+ goto err_buffer_cleanup;
i2c_set_clientdata(client, iio);
return 0;
-regulator_disable:
+err_buffer_cleanup:
+ iio_triggered_buffer_cleanup(iio);
+err_regulator_disable:
regulator_disable(adc->ref);
return err;
@@ -118,13 +207,16 @@ static int adc081c_remove(struct i2c_client *client)
struct adc081c *adc = iio_priv(iio);
iio_device_unregister(iio);
+ iio_triggered_buffer_cleanup(iio);
regulator_disable(adc->ref);
return 0;
}
static const struct i2c_device_id adc081c_id[] = {
- { "adc081c", 0 },
+ { "adc081c", ADC081C },
+ { "adc101c", ADC101C },
+ { "adc121c", ADC121C },
{ }
};
MODULE_DEVICE_TABLE(i2c, adc081c_id);
@@ -132,6 +224,8 @@ MODULE_DEVICE_TABLE(i2c, adc081c_id);
#ifdef CONFIG_OF
static const struct of_device_id adc081c_of_match[] = {
{ .compatible = "ti,adc081c" },
+ { .compatible = "ti,adc101c" },
+ { .compatible = "ti,adc121c" },
{ }
};
MODULE_DEVICE_TABLE(of, adc081c_of_match);
@@ -149,5 +243,5 @@ static struct i2c_driver adc081c_driver = {
module_i2c_driver(adc081c_driver);
MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
-MODULE_DESCRIPTION("Texas Instruments ADC081C021/027 driver");
+MODULE_DESCRIPTION("Texas Instruments ADC081C/ADC101C/ADC121C driver");
MODULE_LICENSE("GPL v2");