| /* |
| * Driver for ADI Direct Digital Synthesis ad9850 |
| * |
| * Copyright (c) 2010-2010 Analog Devices Inc. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| */ |
| #include <linux/types.h> |
| #include <linux/mutex.h> |
| #include <linux/device.h> |
| #include <linux/spi/spi.h> |
| #include <linux/slab.h> |
| #include <linux/sysfs.h> |
| #include <linux/module.h> |
| |
| #include <linux/iio/iio.h> |
| #include <linux/iio/sysfs.h> |
| |
| #define DRV_NAME "ad9850" |
| |
| #define value_mask (u16)0xf000 |
| #define addr_shift 12 |
| |
| /* Register format: 4 bits addr + 12 bits value */ |
| struct ad9850_config { |
| u8 control[5]; |
| }; |
| |
| struct ad9850_state { |
| struct mutex lock; |
| struct spi_device *sdev; |
| }; |
| |
| static ssize_t ad9850_set_parameter(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t len) |
| { |
| struct spi_transfer xfer; |
| int ret; |
| struct ad9850_config *config = (struct ad9850_config *)buf; |
| struct iio_dev *idev = dev_to_iio_dev(dev); |
| struct ad9850_state *st = iio_priv(idev); |
| |
| xfer.len = len; |
| xfer.tx_buf = config; |
| mutex_lock(&st->lock); |
| |
| ret = spi_sync_transfer(st->sdev, &xfer, 1); |
| if (ret) |
| goto error_ret; |
| error_ret: |
| mutex_unlock(&st->lock); |
| |
| return ret ? ret : len; |
| } |
| |
| static IIO_DEVICE_ATTR(dds, S_IWUSR, NULL, ad9850_set_parameter, 0); |
| |
| static struct attribute *ad9850_attributes[] = { |
| &iio_dev_attr_dds.dev_attr.attr, |
| NULL, |
| }; |
| |
| static const struct attribute_group ad9850_attribute_group = { |
| .attrs = ad9850_attributes, |
| }; |
| |
| static const struct iio_info ad9850_info = { |
| .attrs = &ad9850_attribute_group, |
| .driver_module = THIS_MODULE, |
| }; |
| |
| static int ad9850_probe(struct spi_device *spi) |
| { |
| struct ad9850_state *st; |
| struct iio_dev *idev; |
| int ret = 0; |
| |
| idev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); |
| if (!idev) |
| return -ENOMEM; |
| spi_set_drvdata(spi, idev); |
| st = iio_priv(idev); |
| mutex_init(&st->lock); |
| st->sdev = spi; |
| |
| idev->dev.parent = &spi->dev; |
| idev->info = &ad9850_info; |
| idev->modes = INDIO_DIRECT_MODE; |
| |
| ret = iio_device_register(idev); |
| if (ret) |
| return ret; |
| spi->max_speed_hz = 2000000; |
| spi->mode = SPI_MODE_3; |
| spi->bits_per_word = 16; |
| spi_setup(spi); |
| |
| return 0; |
| } |
| |
| static int ad9850_remove(struct spi_device *spi) |
| { |
| iio_device_unregister(spi_get_drvdata(spi)); |
| |
| return 0; |
| } |
| |
| static struct spi_driver ad9850_driver = { |
| .driver = { |
| .name = DRV_NAME, |
| .owner = THIS_MODULE, |
| }, |
| .probe = ad9850_probe, |
| .remove = ad9850_remove, |
| }; |
| module_spi_driver(ad9850_driver); |
| |
| MODULE_AUTHOR("Cliff Cai"); |
| MODULE_DESCRIPTION("Analog Devices ad9850 driver"); |
| MODULE_LICENSE("GPL v2"); |
| MODULE_ALIAS("spi:" DRV_NAME); |