/*
* 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 = IIO_CHAN_INFO_RAW_SEPARATE_BIT, \
.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");
