staging: iio: dds: new driver for AD9951 devices

Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/dds/Kconfig

@@ -37,3 +37,10 @@ config AD9910
 	help
 	  Say yes here to build support for Analog Devices DDS chip
 	  ad9910, provides direct access via sysfs.
+
+config AD9951
+	tristate "Analog Devices ad9951 driver"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices DDS chip
+	  ad9951, provides direct access via sysfs.

drivers/staging/iio/dds/Makefile

@@ -7,3 +7,4 @@ obj-$(CONFIG_AD9832) += ad9832.o
 obj-$(CONFIG_AD9850) += ad9850.o
 obj-$(CONFIG_AD9852) += ad9852.o
 obj-$(CONFIG_AD9910) += ad9910.o
+obj-$(CONFIG_AD9951) += ad9951.o

drivers/staging/iio/dds/ad9951.c

@@ -0,0 +1,254 @@
+/*
+ * Driver for ADI Direct Digital Synthesis ad9951
+ *
+ * Copyright (c) 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 "ad9951"
+
+#define CFR1 0x0
+#define CFR2 0x1
+
+#define AUTO_OSK	(1)
+#define OSKEN		(1 << 1)
+#define LOAD_ARR	(1 << 2)
+
+#define AUTO_SYNC	(1 << 7)
+
+#define LSB_FST		(1)
+#define SDIO_IPT	(1 << 1)
+#define CLR_PHA		(1 << 2)
+#define SINE_OPT	(1 << 4)
+#define ACLR_PHA	(1 << 5)
+
+#define VCO_RANGE	(1 << 2)
+
+#define CRS_OPT		(1 << 1)
+#define HMANU_SYNC	(1 << 2)
+#define HSPD_SYNC	(1 << 3)
+
+/* Register format: 1 byte addr + value */
+struct ad9951_config {
+	u8 asf[3];
+	u8 arr[2];
+	u8 ftw0[5];
+	u8 ftw1[3];
+};
+
+struct ad9951_state {
+	struct mutex lock;
+	struct iio_dev *idev;
+	struct spi_device *sdev;
+};
+
+static ssize_t ad9951_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 ad9951_config *config = (struct ad9951_config *)buf;
+	struct iio_dev *idev = dev_get_drvdata(dev);
+	struct ad9951_state *st = idev->dev_data;
+
+	xfer.len = 3;
+	xfer.tx_buf = &config->asf[0];
+	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;
+
+	xfer.len = 2;
+	xfer.tx_buf = &config->arr[0];
+	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;
+
+	xfer.len = 5;
+	xfer.tx_buf = &config->ftw0[0];
+	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;
+
+	xfer.len = 3;
+	xfer.tx_buf = &config->ftw1[0];
+	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, ad9951_set_parameter, 0);
+
+static void ad9951_init(struct ad9951_state *st)
+{
+	struct spi_message msg;
+	struct spi_transfer xfer;
+	int ret;
+	u8 cfr[5];
+
+	cfr[0] = CFR1;
+	cfr[1] = 0;
+	cfr[2] = LSB_FST | CLR_PHA | SINE_OPT | ACLR_PHA;
+	cfr[3] = AUTO_OSK | OSKEN | LOAD_ARR;
+	cfr[4] = 0;
+
+	mutex_lock(&st->lock);
+
+	xfer.len = 5;
+	xfer.tx_buf = &cfr;
+
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer, &msg);
+	ret = spi_sync(st->sdev, &msg);
+	if (ret)
+		goto error_ret;
+
+	cfr[0] = CFR2;
+	cfr[1] = VCO_RANGE;
+	cfr[2] = HSPD_SYNC;
+	cfr[3] = 0;
+
+	mutex_lock(&st->lock);
+
+	xfer.len = 4;
+	xfer.tx_buf = &cfr;
+
+	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);
+
+
+
+}
+
+static struct attribute *ad9951_attributes[] = {
+	&iio_dev_attr_dds.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ad9951_attribute_group = {
+	.name = DRV_NAME,
+	.attrs = ad9951_attributes,
+};
+
+static int __devinit ad9951_probe(struct spi_device *spi)
+{
+	struct ad9951_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 = &ad9951_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 = 8;
+	spi_setup(spi);
+	ad9951_init(st);
+	return 0;
+
+error_free_dev:
+	iio_free_device(st->idev);
+error_free_st:
+	kfree(st);
+error_ret:
+	return ret;
+}
+
+static int __devexit ad9951_remove(struct spi_device *spi)
+{
+	struct ad9951_state *st = spi_get_drvdata(spi);
+
+	iio_device_unregister(st->idev);
+	kfree(st);
+
+	return 0;
+}
+
+static struct spi_driver ad9951_driver = {
+	.driver = {
+		.name = DRV_NAME,
+		.owner = THIS_MODULE,
+	},
+	.probe = ad9951_probe,
+	.remove = __devexit_p(ad9951_remove),
+};
+
+static __init int ad9951_spi_init(void)
+{
+	return spi_register_driver(&ad9951_driver);
+}
+module_init(ad9951_spi_init);
+
+static __exit void ad9951_spi_exit(void)
+{
+	spi_unregister_driver(&ad9951_driver);
+}
+module_exit(ad9951_spi_exit);
+
+MODULE_AUTHOR("Cliff Cai");
+MODULE_DESCRIPTION("Analog Devices ad9951 driver");
+MODULE_LICENSE("GPL v2");