Commit ae6d9ce0 authored by Martin Fuzzey's avatar Martin Fuzzey Committed by Jonathan Cameron
Browse files

iio: mma8452: Add support for interrupt driven triggers. 



Implement interrupt driven trigger for data ready.
This allows more efficient access to the sample data.

Signed-off-by: default avatarMartin Fuzzey <mfuzzey@parkeon.com>
Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
parent 1e79841a

drivers/iio/accel/mma8452.c

+91 −6
Original line number Diff line number Diff line
@@ -18,6 +18,8 @@ 
#include <linux/iio/sysfs.h>

#include <linux/iio/trigger_consumer.h>

#include <linux/iio/buffer.h>

#include <linux/iio/trigger.h>

#include <linux/iio/trigger_consumer.h>

#include <linux/iio/triggered_buffer.h>

#include <linux/iio/events.h>

#include <linux/delay.h>
@@ -66,6 +68,7 @@ 
#define MMA8452_DATA_CFG_FS_8G 2

#define MMA8452_DATA_CFG_HPF_MASK BIT(4)



#define MMA8452_INT_DRDY	BIT(0)

#define MMA8452_INT_TRANS	BIT(5)



#define MMA8452_DEVICE_ID 0x2a
@@ -577,18 +580,24 @@ static irqreturn_t mma8452_interrupt(int irq, void *p) 
{

	struct iio_dev *indio_dev = p;

	struct mma8452_data *data = iio_priv(indio_dev);

	int ret = IRQ_NONE;

	int src;



	src = i2c_smbus_read_byte_data(data->client, MMA8452_INT_SRC);

	if (src < 0)

		return IRQ_NONE;



	if (src & MMA8452_INT_DRDY) {

		iio_trigger_poll_chained(indio_dev->trig);

		ret = IRQ_HANDLED;

	}



	if (src & MMA8452_INT_TRANS) {

		mma8452_transient_interrupt(indio_dev);

		return IRQ_HANDLED;

		ret = IRQ_HANDLED;

	}



	return IRQ_NONE;

	return ret;

}



static irqreturn_t mma8452_trigger_handler(int irq, void *p)
@@ -714,6 +723,72 @@ static const struct iio_info mma8452_info = { 


static const unsigned long mma8452_scan_masks[] = {0x7, 0};



static int mma8452_data_rdy_trigger_set_state(struct iio_trigger *trig,

					      bool state)

{

	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);

	struct mma8452_data *data = iio_priv(indio_dev);

	int reg;



	reg = i2c_smbus_read_byte_data(data->client, MMA8452_CTRL_REG4);

	if (reg < 0)

		return reg;



	if (state)

		reg |= MMA8452_INT_DRDY;

	else

		reg &= ~MMA8452_INT_DRDY;



	return mma8452_change_config(data, MMA8452_CTRL_REG4, reg);

}



static int mma8452_validate_device(struct iio_trigger *trig,

				   struct iio_dev *indio_dev)

{

	struct iio_dev *indio = iio_trigger_get_drvdata(trig);



	if (indio != indio_dev)

		return -EINVAL;



	return 0;

}



static const struct iio_trigger_ops mma8452_trigger_ops = {

	.set_trigger_state = mma8452_data_rdy_trigger_set_state,

	.validate_device = mma8452_validate_device,

	.owner = THIS_MODULE,

};



static int mma8452_trigger_setup(struct iio_dev *indio_dev)

{

	struct mma8452_data *data = iio_priv(indio_dev);

	struct iio_trigger *trig;

	int ret;



	trig = devm_iio_trigger_alloc(&data->client->dev, "%s-dev%d",

				      indio_dev->name,

				      indio_dev->id);

	if (!trig)

		return -ENOMEM;



	trig->dev.parent = &data->client->dev;

	trig->ops = &mma8452_trigger_ops;

	iio_trigger_set_drvdata(trig, indio_dev);



	ret = iio_trigger_register(trig);

	if (ret)

		return ret;



	indio_dev->trig = trig;

	return 0;

}



static void mma8452_trigger_cleanup(struct iio_dev *indio_dev)

{

	if (indio_dev->trig)

		iio_trigger_unregister(indio_dev->trig);

}



static int mma8452_reset(struct i2c_client *client)

{

	int i;
@@ -794,7 +869,8 @@ static int mma8452_probe(struct i2c_client *client, 
		 * enabled until userspace asks for it by

		 * mma8452_write_event_config()

		 */

		int supported_interrupts = MMA8452_INT_TRANS;

		int supported_interrupts = MMA8452_INT_DRDY | MMA8452_INT_TRANS;

		int enabled_interrupts = MMA8452_INT_TRANS;



		/* Assume wired to INT1 pin */

		ret = i2c_smbus_write_byte_data(client,
@@ -805,7 +881,11 @@ static int mma8452_probe(struct i2c_client *client, 


		ret = i2c_smbus_write_byte_data(client,

						MMA8452_CTRL_REG4,

						supported_interrupts);

						enabled_interrupts);

		if (ret < 0)

			return ret;



		ret = mma8452_trigger_setup(indio_dev);

		if (ret < 0)

			return ret;

	}
@@ -815,12 +895,12 @@ static int mma8452_probe(struct i2c_client *client, 
	ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG1,

					data->ctrl_reg1);

	if (ret < 0)

		return ret;

		goto trigger_cleanup;



	ret = iio_triggered_buffer_setup(indio_dev, NULL,

		mma8452_trigger_handler, NULL);

	if (ret < 0)

		return ret;

		goto trigger_cleanup;



	if (client->irq) {

		ret = devm_request_threaded_irq(&client->dev,
@@ -840,6 +920,10 @@ static int mma8452_probe(struct i2c_client *client, 


buffer_cleanup:

	iio_triggered_buffer_cleanup(indio_dev);



trigger_cleanup:

	mma8452_trigger_cleanup(indio_dev);



	return ret;

}
@@ -849,6 +933,7 @@ static int mma8452_remove(struct i2c_client *client) 


	iio_device_unregister(indio_dev);

	iio_triggered_buffer_cleanup(indio_dev);

	mma8452_trigger_cleanup(indio_dev);

	mma8452_standby(iio_priv(indio_dev));



	return 0;