[deliverable/linux.git] / drivers / iio / adc / viperboard_adc.c

/*
 *  Nano River Technologies viperboard IIO ADC driver
 *
 *  (C) 2012 by Lemonage GmbH
 *  Author: Lars Poeschel <poeschel@lemonage.de>
 *  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.
 *
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>

#include <linux/usb.h>
#include <linux/iio/iio.h>

#include <linux/mfd/viperboard.h>

#define VPRBRD_ADC_CMD_GET		0x00

struct vprbrd_adc_msg {
	u8 cmd;
	u8 chan;
	u8 val;
} __packed;

struct vprbrd_adc {
	struct vprbrd *vb;
};

#define VPRBRD_ADC_CHANNEL(_index) {			\
	.type = IIO_VOLTAGE,				\
	.indexed = 1,					\
	.channel = _index,				\
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
	.scan_index = _index,				\
	.scan_type = {					\
		.sign = 'u',				\
		.realbits = 8,				\
		.storagebits = 8,			\
	},						\
}

static struct iio_chan_spec const vprbrd_adc_iio_channels[] = {
	VPRBRD_ADC_CHANNEL(0),
	VPRBRD_ADC_CHANNEL(1),
	VPRBRD_ADC_CHANNEL(2),
	VPRBRD_ADC_CHANNEL(3),
};

static int vprbrd_iio_read_raw(struct iio_dev *iio_dev,
				struct iio_chan_spec const *chan,
				int *val,
				int *val2,
				long info)
{
	int ret, error = 0;
	struct vprbrd_adc *adc = iio_priv(iio_dev);
	struct vprbrd *vb = adc->vb;
	struct vprbrd_adc_msg *admsg = (struct vprbrd_adc_msg *)vb->buf;

	switch (info) {
	case IIO_CHAN_INFO_RAW:
		mutex_lock(&vb->lock);

		admsg->cmd = VPRBRD_ADC_CMD_GET;
		admsg->chan = chan->scan_index;
		admsg->val = 0x00;

		ret = usb_control_msg(vb->usb_dev,
			usb_sndctrlpipe(vb->usb_dev, 0), VPRBRD_USB_REQUEST_ADC,
			VPRBRD_USB_TYPE_OUT, 0x0000, 0x0000, admsg,
			sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);
		if (ret != sizeof(struct vprbrd_adc_msg)) {
			dev_err(&iio_dev->dev, "usb send error on adc read\n");
			error = -EREMOTEIO;
		}

		ret = usb_control_msg(vb->usb_dev,
			usb_rcvctrlpipe(vb->usb_dev, 0), VPRBRD_USB_REQUEST_ADC,
			VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, admsg,
			sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);

		*val = admsg->val;

		mutex_unlock(&vb->lock);

		if (ret != sizeof(struct vprbrd_adc_msg)) {
			dev_err(&iio_dev->dev, "usb recv error on adc read\n");
			error = -EREMOTEIO;
		}

		if (error)
			goto error;

		return IIO_VAL_INT;
	default:
		error = -EINVAL;
		break;
	}
error:
	return error;
}

static const struct iio_info vprbrd_adc_iio_info = {
	.read_raw = &vprbrd_iio_read_raw,
	.driver_module = THIS_MODULE,
};

static int vprbrd_adc_probe(struct platform_device *pdev)
{
	struct vprbrd *vb = dev_get_drvdata(pdev->dev.parent);
	struct vprbrd_adc *adc;
	struct iio_dev *indio_dev;
	int ret;

	/* registering iio */
	indio_dev = iio_device_alloc(sizeof(*adc));
	if (!indio_dev) {
		dev_err(&pdev->dev, "failed allocating iio device\n");
		return -ENOMEM;
	}

	adc = iio_priv(indio_dev);
	adc->vb = vb;
	indio_dev->name = "viperboard adc";
	indio_dev->dev.parent = &pdev->dev;
	indio_dev->info = &vprbrd_adc_iio_info;
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->channels = vprbrd_adc_iio_channels;
	indio_dev->num_channels = ARRAY_SIZE(vprbrd_adc_iio_channels);

	ret = iio_device_register(indio_dev);
	if (ret) {
		dev_err(&pdev->dev, "could not register iio (adc)");
		goto error;
	}

	platform_set_drvdata(pdev, indio_dev);

	return 0;

error:
	iio_device_free(indio_dev);
	return ret;
}

static int vprbrd_adc_remove(struct platform_device *pdev)
{
	struct iio_dev *indio_dev = platform_get_drvdata(pdev);

	iio_device_unregister(indio_dev);
	iio_device_free(indio_dev);

	return 0;
}

static struct platform_driver vprbrd_adc_driver = {
	.driver = {
		.name	= "viperboard-adc",
		.owner	= THIS_MODULE,
	},
	.probe		= vprbrd_adc_probe,
	.remove		= vprbrd_adc_remove,
};

module_platform_driver(vprbrd_adc_driver);

MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
MODULE_DESCRIPTION("IIO ADC driver for Nano River Techs Viperboard");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:viperboard-adc");
Commit	Line	Data
ffd8a6e7 LP	1	/*
	2	* Nano River Technologies viperboard IIO ADC driver
	3	*
	4	* (C) 2012 by Lemonage GmbH
	5	* Author: Lars Poeschel <poeschel@lemonage.de>
	6	* All rights reserved.
	7	*
	8	* This program is free software; you can redistribute it and/or modify it
	9	* under the terms of the GNU General Public License as published by the
	10	* Free Software Foundation; either version 2 of the License, or (at your
	11	* option) any later version.
	12	*
	13	*/
	14
	15	#include <linux/kernel.h>
	16	#include <linux/errno.h>
	17	#include <linux/module.h>
	18	#include <linux/slab.h>
	19	#include <linux/types.h>
	20	#include <linux/mutex.h>
	21	#include <linux/platform_device.h>
	22
	23	#include <linux/usb.h>
	24	#include <linux/iio/iio.h>
	25
	26	#include <linux/mfd/viperboard.h>
	27
	28	#define VPRBRD_ADC_CMD_GET 0x00
	29
	30	struct vprbrd_adc_msg {
	31	u8 cmd;
	32	u8 chan;
	33	u8 val;
	34	} __packed;
	35
	36	struct vprbrd_adc {
	37	struct vprbrd *vb;
	38	};
	39
	40	#define VPRBRD_ADC_CHANNEL(_index) { \
	41	.type = IIO_VOLTAGE, \
	42	.indexed = 1, \
	43	.channel = _index, \
91239722	44	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
ffd8a6e7 LP	45	.scan_index = _index, \
	46	.scan_type = { \
	47	.sign = 'u', \
	48	.realbits = 8, \
	49	.storagebits = 8, \
	50	}, \
	51	}
	52
	53	static struct iio_chan_spec const vprbrd_adc_iio_channels[] = {
	54	VPRBRD_ADC_CHANNEL(0),
	55	VPRBRD_ADC_CHANNEL(1),
	56	VPRBRD_ADC_CHANNEL(2),
	57	VPRBRD_ADC_CHANNEL(3),
	58	};
	59
	60	static int vprbrd_iio_read_raw(struct iio_dev *iio_dev,
	61	struct iio_chan_spec const *chan,
	62	int *val,
	63	int *val2,
	64	long info)
	65	{
	66	int ret, error = 0;
	67	struct vprbrd_adc *adc = iio_priv(iio_dev);
	68	struct vprbrd *vb = adc->vb;
	69	struct vprbrd_adc_msg admsg = (struct vprbrd_adc_msg )vb->buf;
	70
	71	switch (info) {
	72	case IIO_CHAN_INFO_RAW:
	73	mutex_lock(&vb->lock);
	74
	75	admsg->cmd = VPRBRD_ADC_CMD_GET;
	76	admsg->chan = chan->scan_index;
	77	admsg->val = 0x00;
	78
	79	ret = usb_control_msg(vb->usb_dev,
	80	usb_sndctrlpipe(vb->usb_dev, 0), VPRBRD_USB_REQUEST_ADC,
	81	VPRBRD_USB_TYPE_OUT, 0x0000, 0x0000, admsg,
	82	sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);
	83	if (ret != sizeof(struct vprbrd_adc_msg)) {
	84	dev_err(&iio_dev->dev, "usb send error on adc read\n");
	85	error = -EREMOTEIO;
	86	}
	87
	88	ret = usb_control_msg(vb->usb_dev,
	89	usb_rcvctrlpipe(vb->usb_dev, 0), VPRBRD_USB_REQUEST_ADC,
	90	VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, admsg,
	91	sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);
	92
	93	*val = admsg->val;
	94
	95	mutex_unlock(&vb->lock);
	96
	97	if (ret != sizeof(struct vprbrd_adc_msg)) {
	98	dev_err(&iio_dev->dev, "usb recv error on adc read\n");
	99	error = -EREMOTEIO;
	100	}
	101
	102	if (error)
	103	goto error;
	104
	105	return IIO_VAL_INT;
	106	default:
	107	error = -EINVAL;
	108	break;
109	}
110	error:
111	return error;
112	}
113
114	static const struct iio_info vprbrd_adc_iio_info = {
115	.read_raw = &vprbrd_iio_read_raw,
116	.driver_module = THIS_MODULE,
117	};
118
fc52692c	119	static int vprbrd_adc_probe(struct platform_device *pdev)
ffd8a6e7 LP	120	{
	121	struct vprbrd *vb = dev_get_drvdata(pdev->dev.parent);
	122	struct vprbrd_adc *adc;
	123	struct iio_dev *indio_dev;
	124	int ret;
	125
	126	/* registering iio */
	127	indio_dev = iio_device_alloc(sizeof(*adc));
	128	if (!indio_dev) {
	129	dev_err(&pdev->dev, "failed allocating iio device\n");
	130	return -ENOMEM;
	131	}
	132
	133	adc = iio_priv(indio_dev);
	134	adc->vb = vb;
	135	indio_dev->name = "viperboard adc";
	136	indio_dev->dev.parent = &pdev->dev;
	137	indio_dev->info = &vprbrd_adc_iio_info;
	138	indio_dev->modes = INDIO_DIRECT_MODE;
	139	indio_dev->channels = vprbrd_adc_iio_channels;
	140	indio_dev->num_channels = ARRAY_SIZE(vprbrd_adc_iio_channels);
	141
	142	ret = iio_device_register(indio_dev);
	143	if (ret) {
	144	dev_err(&pdev->dev, "could not register iio (adc)");
	145	goto error;
	146	}
	147
	148	platform_set_drvdata(pdev, indio_dev);
	149
	150	return 0;
	151
	152	error:
	153	iio_device_free(indio_dev);
	154	return ret;
	155	}
	156
fc52692c	157	static int vprbrd_adc_remove(struct platform_device *pdev)
ffd8a6e7 LP	158	{
	159	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
	160
	161	iio_device_unregister(indio_dev);
	162	iio_device_free(indio_dev);
	163
	164	return 0;
	165	}
	166
	167	static struct platform_driver vprbrd_adc_driver = {
	168	.driver = {
	169	.name = "viperboard-adc",
	170	.owner = THIS_MODULE,
	171	},
	172	.probe = vprbrd_adc_probe,
fc52692c	173	.remove = vprbrd_adc_remove,
ffd8a6e7 LP	174	};
	175
	176	module_platform_driver(vprbrd_adc_driver);
	177
	178	MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
	179	MODULE_DESCRIPTION("IIO ADC driver for Nano River Techs Viperboard");
	180	MODULE_LICENSE("GPL");
	181	MODULE_ALIAS("platform:viperboard-adc");