Add data ready trigger for hardware interrupts that notify us when
new measurement samples are available.
Signed-off-by: Narcisa Ana Maria Vasile <narcisaanamaria12@xxxxxxxxx>
---
Note: This patch depends on:
[PATCH v2] iio: chemical: ccs811: Add triggered buffer support
drivers/iio/chemical/ccs811.c | 93 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 92 insertions(+), 1 deletion(-)
diff --git a/drivers/iio/chemical/ccs811.c b/drivers/iio/chemical/ccs811.c
index b59994d..0fd617a 100644
--- a/drivers/iio/chemical/ccs811.c
+++ b/drivers/iio/chemical/ccs811.c
@@ -23,6 +23,7 @@
#include <linux/i2c.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/module.h>
@@ -60,8 +61,13 @@
#define CCS811_MODE_IAQ_60SEC 0x30
#define CCS811_MODE_RAW_DATA 0x40
+#define CCS811_MEAS_MODE_THRESH BIT(2)
+#define CCS811_MEAS_MODE_INTERRUPT BIT(3)
+
#define CCS811_VOLTAGE_MASK 0x3FF
+#define CCS811_IRQ_NAME "ccs811_irq"
+
struct ccs811_reading {
__be16 co2;
__be16 voc;
@@ -74,6 +80,7 @@ struct ccs811_data {
struct i2c_client *client;
struct mutex lock; /* Protect readings */
struct ccs811_reading buffer;
+ struct iio_trigger *drdy_trig;
};
static const struct iio_chan_spec ccs811_channels[] = {
@@ -274,6 +281,54 @@ static int ccs811_read_raw(struct iio_dev *indio_dev,
.driver_module = THIS_MODULE,
};
+static int ccs811_set_trigger_state(struct iio_trigger *trig,
+ bool state)
+{
+ struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+ struct ccs811_data *data = iio_priv(indio_dev);
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(data->client, CCS811_MEAS_MODE);
+ if (ret < 0)
+ return ret;
+
+ if (state)
+ ret |= CCS811_MEAS_MODE_INTERRUPT;
+ else
+ ret &= ~CCS811_MEAS_MODE_INTERRUPT;
+
+ if (data->drdy_trig == trig)
+ ret &= ~CCS811_MEAS_MODE_THRESH;
+
+ return i2c_smbus_write_byte_data(data->client, CCS811_MEAS_MODE, ret);
+}
+
+static const struct iio_trigger_ops ccs811_trigger_ops = {
+ .set_trigger_state = ccs811_set_trigger_state,
+ .owner = THIS_MODULE,
+};
+
+static irqreturn_t ccs811_interrupt_handler(int irq, void *p)
+{
+ struct iio_dev *indio_dev = p;
+ struct ccs811_data *data = iio_priv(indio_dev);
+ u16 buf[8]; /* u16 eCO2 + u16 TVOC + padding + 8 byte timestamp */
+ int ret;
+
+ ret = i2c_smbus_read_i2c_block_data(data->client,
+ CCS811_ALG_RESULT_DATA, 4,
+ (u8 *)&buf);
+ if (ret != 4) {
+ dev_err(&data->client->dev, "cannot read sensor data\n");
+ goto err;
+ }
+
+ iio_push_to_buffers_with_timestamp(indio_dev, buf,
+ iio_get_time_ns(indio_dev));
+err:
+ return IRQ_HANDLED;
+}
+
static irqreturn_t ccs811_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
@@ -347,16 +402,48 @@ static int ccs811_probe(struct i2c_client *client,
indio_dev->dev.parent = &client->dev;
indio_dev->name = id->name;
indio_dev->info = &ccs811_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = ccs811_channels;
indio_dev->num_channels = ARRAY_SIZE(ccs811_channels);
+ if (client->irq > 0) {
+ ret = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL,
+ ccs811_interrupt_handler,
+ IRQF_TRIGGER_FALLING |
+ IRQF_ONESHOT,
+ CCS811_IRQ_NAME, indio_dev);
+ if (ret) {
+ dev_err(&client->dev, "irq request error %d\n", -ret);
+ goto err_poweroff;
+ }
+
+ data->drdy_trig = devm_iio_trigger_alloc(&client->dev,
+ "%s-dev%d",
+ indio_dev->name,
+ indio_dev->id);
+ if (!data->drdy_trig) {
+ ret = -ENOMEM;
+ goto err_poweroff;
+ }
+
+ data->drdy_trig->dev.parent = &client->dev;
+ data->drdy_trig->ops = &ccs811_trigger_ops;
+ iio_trigger_set_drvdata(data->drdy_trig, indio_dev);
+ indio_dev->trig = data->drdy_trig;
+ iio_trigger_get(indio_dev->trig);
+ ret = iio_trigger_register(data->drdy_trig);
+ if (ret)
+ goto err_poweroff;
+ }
+
ret = iio_triggered_buffer_setup(indio_dev, NULL,
ccs811_trigger_handler, NULL);
if (ret < 0) {
dev_err(&client->dev, "triggered buffer setup failed\n");
- goto err_poweroff;
+ goto err_trigger_unregister;
}
ret = iio_device_register(indio_dev);
@@ -368,6 +455,8 @@ static int ccs811_probe(struct i2c_client *client,
err_buffer_cleanup:
iio_triggered_buffer_cleanup(indio_dev);
+err_trigger_unregister:
+ iio_trigger_unregister(data->drdy_trig);
err_poweroff:
i2c_smbus_write_byte_data(client, CCS811_MEAS_MODE, CCS811_MODE_IDLE);
@@ -377,9 +466,11 @@ static int ccs811_probe(struct i2c_client *client,
static int ccs811_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ struct ccs811_data *data = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
+ iio_trigger_unregister(data->drdy_trig);
return i2c_smbus_write_byte_data(client, CCS811_MEAS_MODE,
CCS811_MODE_IDLE);
--
1.9.1
--
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