151 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			151 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-or-later
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| /*
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|  *  Nano River Technologies viperboard IIO ADC driver
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|  *
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|  *  (C) 2012 by Lemonage GmbH
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|  *  Author: Lars Poeschel <poeschel@lemonage.de>
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|  *  All rights reserved.
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|  */
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| 
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| #include <linux/kernel.h>
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| #include <linux/errno.h>
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| #include <linux/module.h>
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| #include <linux/slab.h>
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| #include <linux/types.h>
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| #include <linux/mutex.h>
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| #include <linux/platform_device.h>
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| 
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| #include <linux/usb.h>
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| #include <linux/iio/iio.h>
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| 
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| #include <linux/mfd/viperboard.h>
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| 
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| #define VPRBRD_ADC_CMD_GET		0x00
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| 
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| struct vprbrd_adc_msg {
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| 	u8 cmd;
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| 	u8 chan;
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| 	u8 val;
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| } __packed;
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| 
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| struct vprbrd_adc {
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| 	struct vprbrd *vb;
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| };
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| 
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| #define VPRBRD_ADC_CHANNEL(_index) {			\
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| 	.type = IIO_VOLTAGE,				\
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| 	.indexed = 1,					\
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| 	.channel = _index,				\
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| 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
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| }
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| 
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| static struct iio_chan_spec const vprbrd_adc_iio_channels[] = {
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| 	VPRBRD_ADC_CHANNEL(0),
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| 	VPRBRD_ADC_CHANNEL(1),
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| 	VPRBRD_ADC_CHANNEL(2),
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| 	VPRBRD_ADC_CHANNEL(3),
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| };
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| 
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| static int vprbrd_iio_read_raw(struct iio_dev *iio_dev,
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| 				struct iio_chan_spec const *chan,
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| 				int *val,
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| 				int *val2,
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| 				long info)
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| {
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| 	int ret, error = 0;
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| 	struct vprbrd_adc *adc = iio_priv(iio_dev);
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| 	struct vprbrd *vb = adc->vb;
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| 	struct vprbrd_adc_msg *admsg = (struct vprbrd_adc_msg *)vb->buf;
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| 
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| 	switch (info) {
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| 	case IIO_CHAN_INFO_RAW:
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| 		mutex_lock(&vb->lock);
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| 
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| 		admsg->cmd = VPRBRD_ADC_CMD_GET;
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| 		admsg->chan = chan->channel;
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| 		admsg->val = 0x00;
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| 
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| 		ret = usb_control_msg(vb->usb_dev,
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| 			usb_sndctrlpipe(vb->usb_dev, 0), VPRBRD_USB_REQUEST_ADC,
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| 			VPRBRD_USB_TYPE_OUT, 0x0000, 0x0000, admsg,
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| 			sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);
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| 		if (ret != sizeof(struct vprbrd_adc_msg)) {
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| 			dev_err(&iio_dev->dev, "usb send error on adc read\n");
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| 			error = -EREMOTEIO;
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| 		}
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| 
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| 		ret = usb_control_msg(vb->usb_dev,
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| 			usb_rcvctrlpipe(vb->usb_dev, 0), VPRBRD_USB_REQUEST_ADC,
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| 			VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, admsg,
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| 			sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);
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| 
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| 		*val = admsg->val;
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| 
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| 		mutex_unlock(&vb->lock);
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| 
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| 		if (ret != sizeof(struct vprbrd_adc_msg)) {
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| 			dev_err(&iio_dev->dev, "usb recv error on adc read\n");
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| 			error = -EREMOTEIO;
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| 		}
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| 
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| 		if (error)
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| 			goto error;
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| 
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| 		return IIO_VAL_INT;
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| 	default:
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| 		error = -EINVAL;
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| 		break;
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| 	}
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| error:
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| 	return error;
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| }
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| 
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| static const struct iio_info vprbrd_adc_iio_info = {
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| 	.read_raw = &vprbrd_iio_read_raw,
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| };
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| 
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| static int vprbrd_adc_probe(struct platform_device *pdev)
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| {
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| 	struct vprbrd *vb = dev_get_drvdata(pdev->dev.parent);
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| 	struct vprbrd_adc *adc;
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| 	struct iio_dev *indio_dev;
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| 	int ret;
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| 
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| 	/* registering iio */
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| 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc));
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| 	if (!indio_dev) {
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| 		dev_err(&pdev->dev, "failed allocating iio device\n");
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| 		return -ENOMEM;
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| 	}
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| 
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| 	adc = iio_priv(indio_dev);
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| 	adc->vb = vb;
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| 	indio_dev->name = "viperboard adc";
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| 	indio_dev->info = &vprbrd_adc_iio_info;
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| 	indio_dev->modes = INDIO_DIRECT_MODE;
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| 	indio_dev->channels = vprbrd_adc_iio_channels;
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| 	indio_dev->num_channels = ARRAY_SIZE(vprbrd_adc_iio_channels);
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| 
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| 	ret = devm_iio_device_register(&pdev->dev, indio_dev);
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| 	if (ret) {
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| 		dev_err(&pdev->dev, "could not register iio (adc)");
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| 		return ret;
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| 	}
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| 
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| 	return 0;
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| }
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| 
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| static struct platform_driver vprbrd_adc_driver = {
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| 	.driver = {
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| 		.name	= "viperboard-adc",
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| 	},
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| 	.probe		= vprbrd_adc_probe,
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| };
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| 
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| module_platform_driver(vprbrd_adc_driver);
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| 
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| MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
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| MODULE_DESCRIPTION("IIO ADC driver for Nano River Techs Viperboard");
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| MODULE_LICENSE("GPL");
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| MODULE_ALIAS("platform:viperboard-adc");
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