diff options
Diffstat (limited to 'drivers/iio/adc/viperboard_adc.c')
| -rw-r--r-- | drivers/iio/adc/viperboard_adc.c | 157 |
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"); |