iio: temperature: tmp006: add triggered buffer support

Add support for continuous data capture using triggered buffers for the
tmp006 sensor. The device features a "data ready" interrupt line which
is pulled down once a new measurement is ready to be read.

Signed-off-by: Antoni Pokusinski <apokusinski01@gmail.com>
Link: https://patch.msgid.link/20240908172153.177406-2-apokusinski01@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/temperature/Kconfig b/drivers/iio/temperature/Kconfig
index ed0e4963362f96a0d79e001efd490e03b5a6bd5c..1244d8e17d504ab23425f0c33f5f2d06dadba663 100644 (file)
--- a/drivers/iio/temperature/Kconfig
+++ b/drivers/iio/temperature/Kconfig
@@ -91,6 +91,8 @@ config MLX90635
 config TMP006
        tristate "TMP006 infrared thermopile sensor"
        depends on I2C
+       select IIO_BUFFER
+       select IIO_TRIGGERED_BUFFER
        help
          If you say yes here you get support for the Texas Instruments
          TMP006 infrared thermopile sensor.

diff --git a/drivers/iio/temperature/tmp006.c b/drivers/iio/temperature/tmp006.c
index 6d8d661f0c82aa7e610ae28bc7823143a2381cfa..0c844137d7aa907429a125687f1c91f697d1b878 100644 (file)
--- a/drivers/iio/temperature/tmp006.c
+++ b/drivers/iio/temperature/tmp006.c
@@ -7,8 +7,6 @@
  * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
  *
  * (7-bit I2C slave address 0x40, changeable via ADR pins)
- *
- * TODO: data ready irq
  */
 
 #include <linux/err.h>
@@ -21,6 +19,9 @@
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
 
 #define TMP006_VOBJECT 0x00
 #define TMP006_TAMBIENT 0x01
@@ -45,6 +46,7 @@
 struct tmp006_data {
        struct i2c_client *client;
        u16 config;
+       struct iio_trigger *drdy_trig;
 };
 
 static int tmp006_read_measurement(struct tmp006_data *data, u8 reg)
@@ -83,15 +85,19 @@ static int tmp006_read_raw(struct iio_dev *indio_dev,
        case IIO_CHAN_INFO_RAW:
                if (channel->type == IIO_VOLTAGE) {
                        /* LSB is 156.25 nV */
-                       ret = tmp006_read_measurement(data, TMP006_VOBJECT);
-                       if (ret < 0)
-                               return ret;
+                       iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
+                               ret = tmp006_read_measurement(data, TMP006_VOBJECT);
+                               if (ret < 0)
+                                       return ret;
+                       }
                        *val = sign_extend32(ret, 15);
                } else if (channel->type == IIO_TEMP) {
                        /* LSB is 0.03125 degrees Celsius */
-                       ret = tmp006_read_measurement(data, TMP006_TAMBIENT);
-                       if (ret < 0)
-                               return ret;
+                       iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
+                               ret = tmp006_read_measurement(data, TMP006_TAMBIENT);
+                               if (ret < 0)
+                                       return ret;
+                       }
                        *val = sign_extend32(ret, 15) >> TMP006_TAMBIENT_SHIFT;
                } else {
                        break;
@@ -128,7 +134,7 @@ static int tmp006_write_raw(struct iio_dev *indio_dev,
                            long mask)
 {
        struct tmp006_data *data = iio_priv(indio_dev);
-       int i;
+       int ret, i;
 
        if (mask != IIO_CHAN_INFO_SAMP_FREQ)
                return -EINVAL;
@@ -136,13 +142,19 @@ static int tmp006_write_raw(struct iio_dev *indio_dev,
        for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++)
                if ((val == tmp006_freqs[i][0]) &&
                    (val2 == tmp006_freqs[i][1])) {
+                       ret = iio_device_claim_direct_mode(indio_dev);
+                       if (ret)
+                               return ret;
+
                        data->config &= ~TMP006_CONFIG_CR_MASK;
                        data->config |= i << TMP006_CONFIG_CR_SHIFT;
 
-                       return i2c_smbus_write_word_swapped(data->client,
-                                                           TMP006_CONFIG,
-                                                           data->config);
+                       ret = i2c_smbus_write_word_swapped(data->client,
+                                                          TMP006_CONFIG,
+                                                          data->config);
 
+                       iio_device_release_direct_mode(indio_dev);
+                       return ret;
                }
        return -EINVAL;
 }
@@ -164,13 +176,29 @@ static const struct iio_chan_spec tmp006_channels[] = {
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
                        BIT(IIO_CHAN_INFO_SCALE),
                .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
+               .scan_index = 0,
+               .scan_type = {
+                       .sign = 's',
+                       .realbits = 16,
+                       .storagebits = 16,
+                       .endianness = IIO_BE,
+               }
        },
        {
                .type = IIO_TEMP,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
                        BIT(IIO_CHAN_INFO_SCALE),
                .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
-       }
+               .scan_index = 1,
+               .scan_type = {
+                       .sign = 's',
+                       .realbits = 14,
+                       .storagebits = 16,
+                       .shift = TMP006_TAMBIENT_SHIFT,
+                       .endianness = IIO_BE,
+               }
+       },
+       IIO_CHAN_SOFT_TIMESTAMP(2),
 };
 
 static const struct iio_info tmp006_info = {
@@ -213,6 +241,54 @@ static void tmp006_powerdown_cleanup(void *dev)
        tmp006_power(dev, false);
 }
 
+static irqreturn_t tmp006_trigger_handler(int irq, void *p)
+{
+       struct iio_poll_func *pf = p;
+       struct iio_dev *indio_dev = pf->indio_dev;
+       struct tmp006_data *data = iio_priv(indio_dev);
+       struct {
+               s16 channels[2];
+               s64 ts __aligned(8);
+       } scan;
+       s32 ret;
+
+       ret = i2c_smbus_read_word_data(data->client, TMP006_VOBJECT);
+       if (ret < 0)
+               goto err;
+       scan.channels[0] = ret;
+
+       ret = i2c_smbus_read_word_data(data->client, TMP006_TAMBIENT);
+       if (ret < 0)
+               goto err;
+       scan.channels[1] = ret;
+
+       iio_push_to_buffers_with_timestamp(indio_dev, &scan,
+                                          iio_get_time_ns(indio_dev));
+err:
+       iio_trigger_notify_done(indio_dev->trig);
+       return IRQ_HANDLED;
+}
+
+static int tmp006_set_trigger_state(struct iio_trigger *trig, bool state)
+{
+       struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+       struct tmp006_data *data = iio_priv(indio_dev);
+
+       if (state)
+               data->config |= TMP006_CONFIG_DRDY_EN;
+       else
+               data->config &= ~TMP006_CONFIG_DRDY_EN;
+
+       return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
+                                           data->config);
+}
+
+static const struct iio_trigger_ops tmp006_trigger_ops = {
+       .set_trigger_state = tmp006_set_trigger_state,
+};
+
+static const unsigned long tmp006_scan_masks[] = { 0x3, 0 };
+
 static int tmp006_probe(struct i2c_client *client)
 {
        struct iio_dev *indio_dev;
@@ -241,6 +317,7 @@ static int tmp006_probe(struct i2c_client *client)
 
        indio_dev->channels = tmp006_channels;
        indio_dev->num_channels = ARRAY_SIZE(tmp006_channels);
+       indio_dev->available_scan_masks = tmp006_scan_masks;
 
        ret = i2c_smbus_read_word_swapped(data->client, TMP006_CONFIG);
        if (ret < 0)
@@ -258,6 +335,37 @@ static int tmp006_probe(struct i2c_client *client)
        if (ret < 0)
                return ret;
 
+       if (client->irq > 0) {
+               data->drdy_trig = devm_iio_trigger_alloc(&client->dev,
+                                                        "%s-dev%d",
+                                                        indio_dev->name,
+                                                        iio_device_id(indio_dev));
+               if (!data->drdy_trig)
+                       return -ENOMEM;
+
+               data->drdy_trig->ops = &tmp006_trigger_ops;
+               iio_trigger_set_drvdata(data->drdy_trig, indio_dev);
+               ret = iio_trigger_register(data->drdy_trig);
+               if (ret)
+                       return ret;
+
+               indio_dev->trig = iio_trigger_get(data->drdy_trig);
+
+               ret = devm_request_threaded_irq(&client->dev, client->irq,
+                                               iio_trigger_generic_data_rdy_poll,
+                                               NULL,
+                                               IRQF_ONESHOT,
+                                               "tmp006_irq",
+                                               data->drdy_trig);
+               if (ret < 0)
+                       return ret;
+       }
+
+       ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
+                                             tmp006_trigger_handler, NULL);
+       if (ret < 0)
+               return ret;
+
        return devm_iio_device_register(&client->dev, indio_dev);
 }