1 files changed, 150 insertions, 0 deletions
diff --git a/drivers/iio/adc/viperboard_adc.c b/drivers/iio/adc/viperboard_adc.c
new file mode 100644
index 000000000..1028b101c
--- /dev/null
+++ b/drivers/iio/adc/viperboard_adc.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Nano River Technologies viperboard IIO ADC driver
+ *
+ *  (C) 2012 by Lemonage GmbH
+ *  Author: Lars Poeschel <poeschel@lemonage.de>
+ *  All rights reserved.
+ */
+
+#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),	\
+}
+
+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->channel;
+		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,
+};
+
+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 = devm_iio_device_alloc(&pdev->dev, 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->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 = devm_iio_device_register(&pdev->dev, indio_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "could not register iio (adc)");
+		return ret;
+	}
+
+	return 0;
+}
+
+static struct platform_driver vprbrd_adc_driver = {
+	.driver = {
+		.name	= "viperboard-adc",
+	},
+	.probe		= vprbrd_adc_probe,
+};
+
+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");