diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/staging/iio/dds/ad5930.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/drivers/staging/iio/dds/ad5930.c b/drivers/staging/iio/dds/ad5930.c new file mode 100644 index 000000000000..f80039c5d539 --- /dev/null +++ b/drivers/staging/iio/dds/ad5930.c @@ -0,0 +1,170 @@ +/* + * Driver for ADI Direct Digital Synthesis ad5930 + * + * 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 "../iio.h" +#include "../sysfs.h" + +#define DRV_NAME "ad5930" + +#define value_mask (u16)0xf000 +#define addr_shift 12 + +/* Register format: 4 bits addr + 12 bits value */ +struct ad5903_config { + u16 control; + u16 incnum; + u16 frqdelt[2]; + u16 incitvl; + u16 buritvl; + u16 strtfrq[2]; +}; + +struct ad5930_state { + struct mutex lock; + struct iio_dev *idev; + struct spi_device *sdev; +}; + +static ssize_t ad5930_set_parameter(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct spi_message msg; + struct spi_transfer xfer; + int ret; + struct ad5903_config *config = (struct ad5903_config *)buf; + struct iio_dev *idev = dev_get_drvdata(dev); + struct ad5930_state *st = idev->dev_data; + + config->control = (config->control & ~value_mask); + config->incnum = (config->control & ~value_mask) | (1 << addr_shift); + config->frqdelt[0] = (config->control & ~value_mask) | (2 << addr_shift); + config->frqdelt[1] = (config->control & ~value_mask) | 3 << addr_shift; + config->incitvl = (config->control & ~value_mask) | 4 << addr_shift; + config->buritvl = (config->control & ~value_mask) | 8 << addr_shift; + config->strtfrq[0] = (config->control & ~value_mask) | 0xc << addr_shift; + config->strtfrq[1] = (config->control & ~value_mask) | 0xd << addr_shift; + + xfer.len = len; + xfer.tx_buf = config; + mutex_lock(&st->lock); + + spi_message_init(&msg); + spi_message_add_tail(&xfer, &msg); + ret = spi_sync(st->sdev, &msg); + if (ret) + goto error_ret; +error_ret: + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +static IIO_DEVICE_ATTR(dds, S_IWUSR, NULL, ad5930_set_parameter, 0); + +static struct attribute *ad5930_attributes[] = { + &iio_dev_attr_dds.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ad5930_attribute_group = { + .name = DRV_NAME, + .attrs = ad5930_attributes, +}; + +static int __devinit ad5930_probe(struct spi_device *spi) +{ + struct ad5930_state *st; + int ret = 0; + + st = kzalloc(sizeof(*st), GFP_KERNEL); + if (st == NULL) { + ret = -ENOMEM; + goto error_ret; + } + spi_set_drvdata(spi, st); + + mutex_init(&st->lock); + st->sdev = spi; + + st->idev = iio_allocate_device(); + if (st->idev == NULL) { + ret = -ENOMEM; + goto error_free_st; + } + st->idev->dev.parent = &spi->dev; + st->idev->num_interrupt_lines = 0; + st->idev->event_attrs = NULL; + + st->idev->attrs = &ad5930_attribute_group; + st->idev->dev_data = (void *)(st); + st->idev->driver_module = THIS_MODULE; + st->idev->modes = INDIO_DIRECT_MODE; + + ret = iio_device_register(st->idev); + if (ret) + goto error_free_dev; + spi->max_speed_hz = 2000000; + spi->mode = SPI_MODE_3; + spi->bits_per_word = 16; + spi_setup(spi); + + return 0; + +error_free_dev: + iio_free_device(st->idev); +error_free_st: + kfree(st); +error_ret: + return ret; +} + +static int __devexit ad5930_remove(struct spi_device *spi) +{ + struct ad5930_state *st = spi_get_drvdata(spi); + + iio_device_unregister(st->idev); + kfree(st); + + return 0; +} + +static struct spi_driver ad5930_driver = { + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + }, + .probe = ad5930_probe, + .remove = __devexit_p(ad5930_remove), +}; + +static __init int ad5930_spi_init(void) +{ + return spi_register_driver(&ad5930_driver); +} +module_init(ad5930_spi_init); + +static __exit void ad5930_spi_exit(void) +{ + spi_unregister_driver(&ad5930_driver); +} +module_exit(ad5930_spi_exit); + +MODULE_AUTHOR("Cliff Cai"); +MODULE_DESCRIPTION("Analog Devices ad5930 driver"); +MODULE_LICENSE("GPL v2"); |