iio: imu: adis16400: move burst logic to ADIS lib

This change has been done separately, so that it's easier to visualize the
changed logic in the adis_scan_update() function.

Most of the function in this `adis16400_update_scan_mode()` that deals with
burst-mode will be re-used in the ADIS16480, but with different parameters.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/imu/Makefile

@@ -5,7 +5,6 @@
 
 # When adding new entries keep the list in alphabetical order
 adis16400-y             := adis16400_core.o
-adis16400-$(CONFIG_IIO_BUFFER) += adis16400_buffer.o
 obj-$(CONFIG_ADIS16400) += adis16400.o
 obj-$(CONFIG_ADIS16480) += adis16480.o
 

drivers/iio/imu/adis16400.h

@@ -194,20 +194,4 @@ enum {
 	ADIS16400_SCAN_TIMESTAMP,
 };
 
-#ifdef CONFIG_IIO_BUFFER
-
-ssize_t adis16400_read_data_from_ring(struct device *dev,
-				      struct device_attribute *attr,
-				      char *buf);
-
-
-int adis16400_update_scan_mode(struct iio_dev *indio_dev,
-	const unsigned long *scan_mask);
-
-#else /* CONFIG_IIO_BUFFER */
-
-#define adis16400_update_scan_mode NULL
-
-#endif /* CONFIG_IIO_BUFFER */
-
 #endif /* SPI_ADIS16400_H_ */

drivers/iio/imu/adis16400_buffer.c

-// SPDX-License-Identifier: GPL-2.0
-#include <linux/interrupt.h>
-#include <linux/mutex.h>
-#include <linux/kernel.h>
-#include <linux/spi/spi.h>
-#include <linux/slab.h>
-#include <linux/bitops.h>
-#include <linux/export.h>
-
-#include <linux/iio/iio.h>
-#include <linux/iio/buffer.h>
-#include <linux/iio/triggered_buffer.h>
-#include <linux/iio/trigger_consumer.h>
-
-#include "adis16400.h"
-
-int adis16400_update_scan_mode(struct iio_dev *indio_dev,
-	const unsigned long *scan_mask)
-{
-	struct adis16400_state *st = iio_priv(indio_dev);
-	struct adis *adis = &st->adis;
-	unsigned int burst_length;
-	u8 *tx;
-
-	if (!adis->burst || !adis->burst->en)
-		return adis_update_scan_mode(indio_dev, scan_mask);
-
-	kfree(adis->xfer);
-	kfree(adis->buffer);
-
-	/* All but the timestamp channel */
-	burst_length = (indio_dev->num_channels - 1) * sizeof(u16);
-	burst_length += adis->burst->extra_len;
-
-	adis->xfer = kcalloc(2, sizeof(*adis->xfer), GFP_KERNEL);
-	if (!adis->xfer)
-		return -ENOMEM;
-
-	adis->buffer = kzalloc(burst_length + sizeof(u16), GFP_KERNEL);
-	if (!adis->buffer)
-		return -ENOMEM;
-
-	tx = adis->buffer + burst_length;
-	tx[0] = ADIS_READ_REG(adis->burst->reg_cmd);
-	tx[1] = 0;
-
-	adis->xfer[0].tx_buf = tx;
-	adis->xfer[0].bits_per_word = 8;
-	adis->xfer[0].len = 2;
-	adis->xfer[1].rx_buf = adis->buffer;
-	adis->xfer[1].bits_per_word = 8;
-	adis->xfer[1].len = burst_length;
-
-	spi_message_init(&adis->msg);
-	spi_message_add_tail(&adis->xfer[0], &adis->msg);
-	spi_message_add_tail(&adis->xfer[1], &adis->msg);
-
-	return 0;
-}

drivers/iio/imu/adis16400_core.c

@@ -886,7 +886,7 @@ static struct adis16400_chip_info adis16400_chips[] = {
 static const struct iio_info adis16400_info = {
 	.read_raw = &adis16400_read_raw,
 	.write_raw = &adis16400_write_raw,
-	.update_scan_mode = adis16400_update_scan_mode,
+	.update_scan_mode = adis_update_scan_mode,
 	.debugfs_reg_access = adis_debugfs_reg_access,
 };
 

drivers/iio/imu/adis_buffer.c

@@ -20,6 +20,43 @@
 #include <linux/iio/triggered_buffer.h>
 #include <linux/iio/imu/adis.h>
 
+static int adis_update_scan_mode_burst(struct iio_dev *indio_dev,
+	const unsigned long *scan_mask)
+{
+	struct adis *adis = iio_device_get_drvdata(indio_dev);
+	unsigned int burst_length;
+	u8 *tx;
+
+	/* All but the timestamp channel */
+	burst_length = (indio_dev->num_channels - 1) * sizeof(u16);
+	burst_length += adis->burst->extra_len;
+
+	adis->xfer = kcalloc(2, sizeof(*adis->xfer), GFP_KERNEL);
+	if (!adis->xfer)
+		return -ENOMEM;
+
+	adis->buffer = kzalloc(burst_length + sizeof(u16), GFP_KERNEL);
+	if (!adis->buffer)
+		return -ENOMEM;
+
+	tx = adis->buffer + burst_length;
+	tx[0] = ADIS_READ_REG(adis->burst->reg_cmd);
+	tx[1] = 0;
+
+	adis->xfer[0].tx_buf = tx;
+	adis->xfer[0].bits_per_word = 8;
+	adis->xfer[0].len = 2;
+	adis->xfer[1].rx_buf = adis->buffer;
+	adis->xfer[1].bits_per_word = 8;
+	adis->xfer[1].len = burst_length;
+
+	spi_message_init(&adis->msg);
+	spi_message_add_tail(&adis->xfer[0], &adis->msg);
+	spi_message_add_tail(&adis->xfer[1], &adis->msg);
+
+	return 0;
+}
+
 int adis_update_scan_mode(struct iio_dev *indio_dev,
 	const unsigned long *scan_mask)
 {
@@ -32,6 +69,9 @@ int adis_update_scan_mode(struct iio_dev *indio_dev,
 	kfree(adis->xfer);
 	kfree(adis->buffer);
 
+	if (adis->burst && adis->burst->en)
+		return adis_update_scan_mode_burst(indio_dev, scan_mask);
+
 	scan_count = indio_dev->scan_bytes / 2;
 
 	adis->xfer = kcalloc(scan_count + 1, sizeof(*adis->xfer), GFP_KERNEL);