iio: pressure: ms5611: Add triggered buffer support

This will be used together with an external trigger (e.g hrtimer
based software trigger).
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/pressure/Kconfig

@@ -69,6 +69,7 @@ config MPL3115
 
 config MS5611
 	tristate "Measurement Specialties MS5611 pressure sensor driver"
+	select IIO_TRIGGERED_BUFFER
 	help
 	  Say Y here to build support for the Measurement Specialties
 	  MS5611, MS5607 pressure and temperature sensors.

drivers/iio/pressure/ms5611.h

@@ -52,5 +52,6 @@ struct ms5611_state {
 };
 
 int ms5611_probe(struct iio_dev *indio_dev, struct device *dev, int type);
+int ms5611_remove(struct iio_dev *indio_dev);
 
 #endif /* _MS5611_H */

drivers/iio/pressure/ms5611_core.c

@@ -17,6 +17,9 @@
 #include <linux/iio/iio.h>
 #include <linux/delay.h>
 
+#include <linux/iio/buffer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
 #include "ms5611.h"
 
 static bool ms5611_prom_is_valid(u16 *prom, size_t len)
@@ -173,6 +176,28 @@ static int ms5611_reset(struct iio_dev *indio_dev)
 	return 0;
 }
 
+static irqreturn_t ms5611_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct ms5611_state *st = iio_priv(indio_dev);
+	s32 buf[4]; /* s32 (pressure) + s32 (temp) + 2 * s32 (timestamp) */
+	int ret;
+
+	mutex_lock(&st->lock);
+	ret = ms5611_read_temp_and_pressure(indio_dev, &buf[1], &buf[0]);
+	mutex_unlock(&st->lock);
+	if (ret < 0)
+		goto err;
+
+	iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns());
+
+err:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
 static int ms5611_read_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan,
 			   int *val, int *val2, long mask)
@@ -218,6 +243,8 @@ static int ms5611_read_raw(struct iio_dev *indio_dev,
 	return -EINVAL;
 }
 
+static const unsigned long ms5611_scan_masks[] = {0x3, 0};
+
 static struct ms5611_chip_info chip_info_tbl[] = {
 	[MS5611] = {
 		.temp_and_pressure_compensate = ms5611_temp_and_pressure_compensate,
@@ -232,12 +259,27 @@ static const struct iio_chan_spec ms5611_channels[] = {
 		.type = IIO_PRESSURE,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
 			BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = 0,
+		.scan_type = {
+			.sign = 's',
+			.realbits = 32,
+			.storagebits = 32,
+			.endianness = IIO_CPU,
+		},
 	},
 	{
 		.type = IIO_TEMP,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
 			BIT(IIO_CHAN_INFO_SCALE),
-	}
+		.scan_index = 1,
+		.scan_type = {
+			.sign = 's',
+			.realbits = 32,
+			.storagebits = 32,
+			.endianness = IIO_CPU,
+		},
+	},
+	IIO_CHAN_SOFT_TIMESTAMP(2),
 };
 
 static const struct iio_info ms5611_info = {
@@ -269,15 +311,43 @@ int ms5611_probe(struct iio_dev *indio_dev, struct device *dev, int type)
 	indio_dev->channels = ms5611_channels;
 	indio_dev->num_channels = ARRAY_SIZE(ms5611_channels);
 	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->available_scan_masks = ms5611_scan_masks;
 
 	ret = ms5611_init(indio_dev);
 	if (ret < 0)
 		return ret;
 
-	return devm_iio_device_register(dev, indio_dev);
+	ret = iio_triggered_buffer_setup(indio_dev, NULL,
+					 ms5611_trigger_handler, NULL);
+	if (ret < 0) {
+		dev_err(dev, "iio triggered buffer setup failed\n");
+		return ret;
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(dev, "unable to register iio device\n");
+		goto err_buffer_cleanup;
+	}
+
+	return 0;
+
+err_buffer_cleanup:
+	iio_triggered_buffer_cleanup(indio_dev);
+
+	return ret;
 }
 EXPORT_SYMBOL(ms5611_probe);
 
+int ms5611_remove(struct iio_dev *indio_dev)
+{
+	iio_device_unregister(indio_dev);
+	iio_triggered_buffer_cleanup(indio_dev);
+
+	return 0;
+}
+EXPORT_SYMBOL(ms5611_remove);
+
 MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
 MODULE_DESCRIPTION("MS5611 core driver");
 MODULE_LICENSE("GPL v2");

drivers/iio/pressure/ms5611_i2c.c

@@ -99,6 +99,7 @@ static int ms5611_i2c_probe(struct i2c_client *client,
 		return -ENOMEM;
 
 	st = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
 	st->reset = ms5611_i2c_reset;
 	st->read_prom_word = ms5611_i2c_read_prom_word;
 	st->read_adc_temp_and_pressure = ms5611_i2c_read_adc_temp_and_pressure;
@@ -107,6 +108,11 @@ static int ms5611_i2c_probe(struct i2c_client *client,
 	return ms5611_probe(indio_dev, &client->dev, id->driver_data);
 }
 
+static int ms5611_i2c_remove(struct i2c_client *client)
+{
+	return ms5611_remove(i2c_get_clientdata(client));
+}
+
 static const struct i2c_device_id ms5611_id[] = {
 	{ "ms5611", MS5611 },
 	{ "ms5607", MS5607 },
@@ -120,6 +126,7 @@ static struct i2c_driver ms5611_driver = {
 	},
 	.id_table = ms5611_id,
 	.probe = ms5611_i2c_probe,
+	.remove = ms5611_i2c_remove,
 };
 module_i2c_driver(ms5611_driver);
 

drivers/iio/pressure/ms5611_spi.c

@@ -90,6 +90,8 @@ static int ms5611_spi_probe(struct spi_device *spi)
 	if (!indio_dev)
 		return -ENOMEM;
 
+	spi_set_drvdata(spi, indio_dev);
+
 	spi->mode = SPI_MODE_0;
 	spi->max_speed_hz = 20000000;
 	spi->bits_per_word = 8;
@@ -107,6 +109,11 @@ static int ms5611_spi_probe(struct spi_device *spi)
 			    spi_get_device_id(spi)->driver_data);
 }
 
+static int ms5611_spi_remove(struct spi_device *spi)
+{
+	return ms5611_remove(spi_get_drvdata(spi));
+}
+
 static const struct spi_device_id ms5611_id[] = {
 	{ "ms5611", MS5611 },
 	{ "ms5607", MS5607 },
@@ -120,6 +127,7 @@ static struct spi_driver ms5611_driver = {
 	},
 	.id_table = ms5611_id,
 	.probe = ms5611_spi_probe,
+	.remove = ms5611_spi_remove,
 };
 module_spi_driver(ms5611_driver);