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path: root/drivers/iio/adc/viperboard_adc.c
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Diffstat (limited to 'drivers/iio/adc/viperboard_adc.c')
-rw-r--r--drivers/iio/adc/viperboard_adc.c157
1 files changed, 157 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..3be2e3572
--- /dev/null
+++ b/drivers/iio/adc/viperboard_adc.c
@@ -0,0 +1,157 @@
+/*
+ * 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), \
+}
+
+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,
+ .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 = 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->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 = 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");