Re: [PATCH v3 5/5] iio: common: ssp_sensors: Add sensorhub gyroscope sensor

[Jonathan Cameron <jic23@kernel.org>]

On 05/12/14 19:54, Karol Wrona wrote:
> This patch adds gyroscope iio driver which uses sensorhub as data
> provider.
> 
> Change-Id: Ia16bc92159d062a29957de8e62ea3fefdcd7985a
> Signed-off-by: Karol Wrona <k.wrona@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
hmm.  This is obviously very similar to the accelerometer driver so same
comments (I haven't read it ;)
> ---
>  drivers/iio/gyro/Makefile          |    2 +
>  drivers/iio/gyro/ssp_gyro_sensor.c |  202 ++++++++++++++++++++++++++++++++++++
>  2 files changed, 204 insertions(+)
>  create mode 100644 drivers/iio/gyro/ssp_gyro_sensor.c
> 
> diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
> index 36a3877..68f1437 100644
> --- a/drivers/iio/gyro/Makefile
> +++ b/drivers/iio/gyro/Makefile
> @@ -16,6 +16,8 @@ itg3200-y               := itg3200_core.o
>  itg3200-$(CONFIG_IIO_BUFFER) += itg3200_buffer.o
>  obj-$(CONFIG_ITG3200)   += itg3200.o
>  
> +obj-$(CONFIG_IIO_SSP_SENSOR) += ssp_gyro_sensor.o
> +
>  obj-$(CONFIG_IIO_ST_GYRO_3AXIS) += st_gyro.o
>  st_gyro-y := st_gyro_core.o
>  st_gyro-$(CONFIG_IIO_BUFFER) += st_gyro_buffer.o
> diff --git a/drivers/iio/gyro/ssp_gyro_sensor.c b/drivers/iio/gyro/ssp_gyro_sensor.c
> new file mode 100644
> index 0000000..5820a43
> --- /dev/null
> +++ b/drivers/iio/gyro/ssp_gyro_sensor.c
> @@ -0,0 +1,202 @@
> +/*
> + *  Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
> + *
> + *  This program is free software; you can redistribute it and/or modify
> + *  it under the terms of the GNU General Public License as published by
> + *  the Free Software Foundation; either version 2 of the License, or
> + *  (at your option) any later version.
> + *
> + *  This program is distributed in the hope that it will be useful,
> + *  but WITHOUT ANY WARRANTY; without even the implied warranty of
> + *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + *  GNU General Public License for more details.
> + *
> + */
> +
> +#include <linux/iio/common/ssp_sensors.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/kfifo_buf.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include "../common/ssp_sensors/ssp_iio_sensor.h"
> +
> +#define SSP_CHANNEL_COUNT 3
> +
> +#define SSP_GYROSCOPE_NAME "ssp-gyroscope"
> +static const char ssp_gyro_name[] = SSP_GYROSCOPE_NAME;
> +
> +enum ssp_gyro_3d_channel {
> +	SSP_CHANNEL_SCAN_INDEX_X,
> +	SSP_CHANNEL_SCAN_INDEX_Y,
> +	SSP_CHANNEL_SCAN_INDEX_Z,
> +	SSP_CHANNEL_SCAN_INDEX_TIME,
> +	GYRO_3D_CHANNEL_MAX,
> +};
> +
> +static int ssp_gyro_read_raw(struct iio_dev *indio_dev,
> +			     struct iio_chan_spec const *chan, int *val,
> +			     int *val2, long mask)
> +{
> +	u32 t;
> +	struct ssp_data *data = dev_get_drvdata(indio_dev->dev.parent->parent);
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		t = ssp_get_sensor_delay(data, SSP_GYROSCOPE_SENSOR);
> +		ssp_convert_to_freq(t, val, val2);
> +		return IIO_VAL_INT_PLUS_MICRO;
> +	default:
> +		break;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int ssp_gyro_write_raw(struct iio_dev *indio_dev,
> +			      struct iio_chan_spec const *chan, int val,
> +			      int val2, long mask)
> +{
> +	int ret;
> +	struct ssp_data *data = dev_get_drvdata(indio_dev->dev.parent->parent);
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		ret = ssp_convert_to_time(val, val2);
> +		ret = ssp_change_delay(data, SSP_GYROSCOPE_SENSOR, ret);
> +		if (ret < 0)
> +			dev_err(&indio_dev->dev, "gyro sensor enable fail\n");
> +
> +		return ret;
> +	default:
> +		break;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static struct iio_info ssp_gyro_iio_info = {
> +	.read_raw = &ssp_gyro_read_raw,
> +	.write_raw = &ssp_gyro_write_raw,
> +};
> +
> +static const struct iio_chan_spec ssp_gyro_channels[] = {
> +	SSP_CHANNEL_AG(IIO_ANGL_VEL, IIO_MOD_X, SSP_CHANNEL_SCAN_INDEX_X),
> +	SSP_CHANNEL_AG(IIO_ANGL_VEL, IIO_MOD_Y, SSP_CHANNEL_SCAN_INDEX_Y),
> +	SSP_CHANNEL_AG(IIO_ANGL_VEL, IIO_MOD_Z, SSP_CHANNEL_SCAN_INDEX_Z),
> +	IIO_CHAN_SOFT_TIMESTAMP(SSP_CHANNEL_SCAN_INDEX_TIME),
> +};
> +
> +static int ssp_process_gyro_data(struct iio_dev *indio_dev, void *buf,
> +				 int64_t timestamp)
> +{
> +	__le32 time;
> +	const int len = SSP_GYROSCOPE_SIZE;
> +	int64_t calculated_time;
> +	char *data;
> +	int ret;
> +
> +	if (indio_dev->scan_bytes == 0)
> +		return 0;
> +
> +	data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	memcpy(data, buf, len);
> +
> +	if (indio_dev->scan_timestamp) {
> +		memcpy(&time, &((char *)buf)[len], SSP_TIME_SIZE);
> +		calculated_time =
> +			timestamp + (int64_t)le32_to_cpu(time) * 1000000;
> +	}
> +
> +	ret = iio_push_to_buffers_with_timestamp(indio_dev, data,
> +						 calculated_time);
> +
> +	kfree(data);
> +
> +	return ret;
> +}
> +
> +static const struct iio_buffer_setup_ops ssp_gyro_buffer_ops = {
> +	.postenable = &ssp_common_buffer_postenable,
> +	.predisable = &ssp_common_buffer_predisable,
> +};
> +
> +static int ssp_gyro_probe(struct platform_device *pdev)
> +{
> +	int ret;
> +	struct iio_dev *indio_dev;
> +	struct ssp_sensor_data *spd;
> +
> +	indio_dev = iio_device_alloc(sizeof(*spd));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	spd = iio_priv(indio_dev);
> +
> +	spd->process_data = ssp_process_gyro_data;
> +	spd->type = SSP_GYROSCOPE_SENSOR;
> +
> +	indio_dev->name = ssp_gyro_name;
> +	indio_dev->dev.parent = &pdev->dev;
> +	indio_dev->info = &ssp_gyro_iio_info;
> +	indio_dev->modes = INDIO_BUFFER_HARDWARE;
> +	indio_dev->channels = ssp_gyro_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(ssp_gyro_channels);
> +
> +	ret = ssp_common_setup_buffer(indio_dev, &ssp_gyro_buffer_ops);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "Buffer setup fail\n");
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, indio_dev);
> +
> +	ret = iio_device_register(indio_dev);
> +	if (ret < 0) {
> +		iio_buffer_unregister(indio_dev);
> +		iio_kfifo_free(indio_dev->buffer);
> +		return ret;
> +	};
> +
> +	/* similar to accel */
> +	ssp_register_consumer(indio_dev, SSP_GYROSCOPE_SENSOR);
> +
> +	return 0;
> +}
> +
> +static int ssp_gyro_remove(struct platform_device *pdev)
> +{
> +	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
> +
> +	iio_device_unregister(indio_dev);
> +	iio_buffer_unregister(indio_dev);
> +	iio_kfifo_free(indio_dev->buffer);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id ssp_gyro_id_table[] = {
> +	{
> +		.compatible = "samsung,mpu6500-gyro",
> +	},
> +	{},
> +};
> +
> +static struct platform_driver ssp_gyro_driver = {
> +	.driver = {
> +		.owner = THIS_MODULE,
> +		.name = SSP_GYROSCOPE_NAME,
> +		.of_match_table = ssp_gyro_id_table,
> +	},
> +	.probe = ssp_gyro_probe,
> +	.remove = ssp_gyro_remove,
> +};
> +
> +module_platform_driver(ssp_gyro_driver);
> +
> +MODULE_AUTHOR("Karol Wrona <k.wrona@samsung.com>");
> +MODULE_DESCRIPTION("Samsung sensorhub gyroscopes driver");
> +MODULE_LICENSE("GPL");
>