[media] airspy: AirSpy SDR driver

AirSpy SDR driver.

Thanks to Youssef Touil and Benjamin Vernoux for support, help and
hardware!
http://airspy.com/Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

drivers/staging/media/Kconfig

@@ -19,6 +19,7 @@ menuconfig STAGING_MEDIA
 if STAGING_MEDIA
 
 # Please keep them in alphabetic order
+source "drivers/staging/media/airspy/Kconfig"
 source "drivers/staging/media/as102/Kconfig"
 
 source "drivers/staging/media/bcm2048/Kconfig"

drivers/staging/media/Makefile

+obj-$(CONFIG_USB_AIRSPY)	+= airspy/
 obj-$(CONFIG_DVB_AS102)		+= as102/
 obj-$(CONFIG_I2C_BCM2048)	+= bcm2048/
 obj-$(CONFIG_DVB_CXD2099)	+= cxd2099/

drivers/staging/media/airspy/Kconfig

+config USB_AIRSPY
+	tristate "AirSpy"
+	depends on USB && VIDEO_DEV && VIDEO_V4L2 && I2C
+	select VIDEOBUF2_VMALLOC
+	default m if !MEDIA_SUBDRV_AUTOSELECT

drivers/staging/media/airspy/Makefile

+obj-$(CONFIG_USB_AIRSPY)              += airspy.o

drivers/staging/media/airspy/airspy.c

+/*
+ * AirSpy SDR driver
+ *
+ * Copyright (C) 2014 Antti Palosaari <crope@iki.fi>
+ *
+ *    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.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-event.h>
+#include <media/videobuf2-vmalloc.h>
+
+/* AirSpy USB API commands (from AirSpy Library) */
+enum {
+	CMD_INVALID                       = 0x00,
+	CMD_RECEIVER_MODE                 = 0x01,
+	CMD_SI5351C_WRITE                 = 0x02,
+	CMD_SI5351C_READ                  = 0x03,
+	CMD_R820T_WRITE                   = 0x04,
+	CMD_R820T_READ                    = 0x05,
+	CMD_SPIFLASH_ERASE                = 0x06,
+	CMD_SPIFLASH_WRITE                = 0x07,
+	CMD_SPIFLASH_READ                 = 0x08,
+	CMD_BOARD_ID_READ                 = 0x09,
+	CMD_VERSION_STRING_READ           = 0x0a,
+	CMD_BOARD_PARTID_SERIALNO_READ    = 0x0b,
+	CMD_SET_SAMPLE_RATE               = 0x0c,
+	CMD_SET_FREQ                      = 0x0d,
+	CMD_SET_LNA_GAIN                  = 0x0e,
+	CMD_SET_MIXER_GAIN                = 0x0f,
+	CMD_SET_VGA_GAIN                  = 0x10,
+	CMD_SET_LNA_AGC                   = 0x11,
+	CMD_SET_MIXER_AGC                 = 0x12,
+	CMD_SET_PACKING                   = 0x13,
+};
+
+/*
+ *       bEndpointAddress     0x81  EP 1 IN
+ *         Transfer Type            Bulk
+ *       wMaxPacketSize     0x0200  1x 512 bytes
+ */
+#define MAX_BULK_BUFS            (6)
+#define BULK_BUFFER_SIZE         (128 * 512)
+
+static const struct v4l2_frequency_band bands[] = {
+	{
+		.tuner = 0,
+		.type = V4L2_TUNER_ADC,
+		.index = 0,
+		.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
+		.rangelow   = 20000000,
+		.rangehigh  = 20000001, /* FIXME: make v4l2-compliance happy */
+	},
+};
+
+static const struct v4l2_frequency_band bands_rf[] = {
+	{
+		.tuner = 1,
+		.type = V4L2_TUNER_RF,
+		.index = 0,
+		.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
+		.rangelow   =   24000000,
+		.rangehigh  = 1750000000,
+	},
+};
+
+/* stream formats */
+struct airspy_format {
+	char	*name;
+	u32	pixelformat;
+};
+
+/* format descriptions for capture and preview */
+static struct airspy_format formats[] = {
+	{
+		.name		= "Real U12LE",
+		.pixelformat	=  V4L2_SDR_FMT_RU12LE,
+	},
+};
+
+static const unsigned int NUM_FORMATS = ARRAY_SIZE(formats);
+
+/* intermediate buffers with raw data from the USB device */
+struct airspy_frame_buf {
+	struct vb2_buffer vb;   /* common v4l buffer stuff -- must be first */
+	struct list_head list;
+};
+
+struct airspy {
+#define POWER_ON           (1 << 1)
+#define URB_BUF            (1 << 2)
+#define USB_STATE_URB_BUF  (1 << 3)
+	unsigned long flags;
+
+	struct usb_device *udev;
+	struct video_device vdev;
+	struct v4l2_device v4l2_dev;
+
+	/* videobuf2 queue and queued buffers list */
+	struct vb2_queue vb_queue;
+	struct list_head queued_bufs;
+	spinlock_t queued_bufs_lock; /* Protects queued_bufs */
+	unsigned sequence;	     /* Buffer sequence counter */
+	unsigned int vb_full;        /* vb is full and packets dropped */
+
+	/* Note if taking both locks v4l2_lock must always be locked first! */
+	struct mutex v4l2_lock;      /* Protects everything else */
+	struct mutex vb_queue_lock;  /* Protects vb_queue and capt_file */
+
+	struct urb     *urb_list[MAX_BULK_BUFS];
+	int            buf_num;
+	unsigned long  buf_size;
+	u8             *buf_list[MAX_BULK_BUFS];
+	dma_addr_t     dma_addr[MAX_BULK_BUFS];
+	int            urbs_initialized;
+	int            urbs_submitted;
+
+	/* USB control message buffer */
+	#define BUF_SIZE 24
+	u8 buf[BUF_SIZE];
+
+	/* Current configuration */
+	unsigned int f_adc;
+	unsigned int f_rf;
+	u32 pixelformat;
+
+	/* Controls */
+	struct v4l2_ctrl_handler hdl;
+	struct v4l2_ctrl *lna_gain_auto;
+	struct v4l2_ctrl *lna_gain;
+	struct v4l2_ctrl *mixer_gain_auto;
+	struct v4l2_ctrl *mixer_gain;
+	struct v4l2_ctrl *if_gain;
+
+	/* Sample rate calc */
+	unsigned long jiffies_next;
+	unsigned int sample;
+	unsigned int sample_measured;
+};
+
+#define airspy_dbg_usb_control_msg(_udev, _r, _t, _v, _i, _b, _l) { \
+	char *_direction; \
+	if (_t & USB_DIR_IN) \
+		_direction = "<<<"; \
+	else \
+		_direction = ">>>"; \
+	dev_dbg(&_udev->dev, "%s: %02x %02x %02x %02x %02x %02x %02x %02x " \
+			"%s %*ph\n",  __func__, _t, _r, _v & 0xff, _v >> 8, \
+			_i & 0xff, _i >> 8, _l & 0xff, _l >> 8, _direction, \
+			_l, _b); \
+}
+
+/* execute firmware command */
+static int airspy_ctrl_msg(struct airspy *s, u8 request, u16 value, u16 index,
+		u8 *data, u16 size)
+{
+	int ret;
+	unsigned int pipe;
+	u8 requesttype;
+
+	switch (request) {
+	case CMD_RECEIVER_MODE:
+	case CMD_SET_FREQ:
+		pipe = usb_sndctrlpipe(s->udev, 0);
+		requesttype = (USB_TYPE_VENDOR | USB_DIR_OUT);
+		break;
+	case CMD_BOARD_ID_READ:
+	case CMD_VERSION_STRING_READ:
+	case CMD_BOARD_PARTID_SERIALNO_READ:
+	case CMD_SET_LNA_GAIN:
+	case CMD_SET_MIXER_GAIN:
+	case CMD_SET_VGA_GAIN:
+	case CMD_SET_LNA_AGC:
+	case CMD_SET_MIXER_AGC:
+		pipe = usb_rcvctrlpipe(s->udev, 0);
+		requesttype = (USB_TYPE_VENDOR | USB_DIR_IN);
+		break;
+	default:
+		dev_err(&s->udev->dev, "Unknown command %02x\n", request);
+		ret = -EINVAL;
+		goto err;
+	}
+
+	/* write request */
+	if (!(requesttype & USB_DIR_IN))
+		memcpy(s->buf, data, size);
+
+	ret = usb_control_msg(s->udev, pipe, request, requesttype, value,
+			index, s->buf, size, 1000);
+	airspy_dbg_usb_control_msg(s->udev, request, requesttype, value,
+			index, s->buf, size);
+	if (ret < 0) {
+		dev_err(&s->udev->dev,
+				"usb_control_msg() failed %d request %02x\n",
+				ret, request);
+		goto err;
+	}
+
+	/* read request */
+	if (requesttype & USB_DIR_IN)
+		memcpy(data, s->buf, size);
+
+	return 0;
+err:
+	return ret;
+}
+
+/* Private functions */
+static struct airspy_frame_buf *airspy_get_next_fill_buf(struct airspy *s)
+{
+	unsigned long flags = 0;
+	struct airspy_frame_buf *buf = NULL;
+
+	spin_lock_irqsave(&s->queued_bufs_lock, flags);
+	if (list_empty(&s->queued_bufs))
+		goto leave;
+
+	buf = list_entry(s->queued_bufs.next,
+			struct airspy_frame_buf, list);
+	list_del(&buf->list);
+leave:
+	spin_unlock_irqrestore(&s->queued_bufs_lock, flags);
+	return buf;
+}
+
+static unsigned int airspy_convert_stream(struct airspy *s,
+		void *dst, void *src, unsigned int src_len)
+{
+	unsigned int dst_len;
+
+	if (s->pixelformat == V4L2_SDR_FMT_RU12LE) {
+		memcpy(dst, src, src_len);
+		dst_len = src_len;
+	} else {
+		dst_len = 0;
+	}
+
+	/* calculate samping rate and output it in 10 seconds intervals */
+	if (unlikely(time_is_before_jiffies(s->jiffies_next))) {
+		#define MSECS 10000UL
+		unsigned int samples = s->sample - s->sample_measured;
+		s->jiffies_next = jiffies + msecs_to_jiffies(MSECS);
+		s->sample_measured = s->sample;
+		dev_dbg(&s->udev->dev,
+				"slen=%d samples=%u msecs=%lu sample rate=%lu\n",
+				src_len, samples, MSECS,
+				samples * 1000UL / MSECS);
+	}
+
+	/* total number of samples */
+	s->sample += src_len / 2;
+
+	return dst_len;
+}
+
+/*
+ * This gets called for the bulk stream pipe. This is done in interrupt
+ * time, so it has to be fast, not crash, and not stall. Neat.
+ */
+static void airspy_urb_complete(struct urb *urb)
+{
+	struct airspy *s = urb->context;
+	struct airspy_frame_buf *fbuf;
+
+	dev_dbg_ratelimited(&s->udev->dev,
+			"%s: status=%d length=%d/%d errors=%d\n",
+			__func__, urb->status, urb->actual_length,
+			urb->transfer_buffer_length, urb->error_count);
+
+	switch (urb->status) {
+	case 0:             /* success */
+	case -ETIMEDOUT:    /* NAK */
+		break;
+	case -ECONNRESET:   /* kill */
+	case -ENOENT:
+	case -ESHUTDOWN:
+		return;
+	default:            /* error */
+		dev_err_ratelimited(&s->udev->dev, "URB failed %d\n",
+				urb->status);
+		break;
+	}
+
+	if (likely(urb->actual_length > 0)) {
+		void *ptr;
+		unsigned int len;
+		/* get free framebuffer */
+		fbuf = airspy_get_next_fill_buf(s);
+		if (unlikely(fbuf == NULL)) {
+			s->vb_full++;
+			dev_notice_ratelimited(&s->udev->dev,
+					"videobuf is full, %d packets dropped\n",
+					s->vb_full);
+			goto skip;
+		}
+
+		/* fill framebuffer */
+		ptr = vb2_plane_vaddr(&fbuf->vb, 0);
+		len = airspy_convert_stream(s, ptr, urb->transfer_buffer,
+				urb->actual_length);
+		vb2_set_plane_payload(&fbuf->vb, 0, len);
+		v4l2_get_timestamp(&fbuf->vb.v4l2_buf.timestamp);
+		fbuf->vb.v4l2_buf.sequence = s->sequence++;
+		vb2_buffer_done(&fbuf->vb, VB2_BUF_STATE_DONE);
+	}
+skip:
+	usb_submit_urb(urb, GFP_ATOMIC);
+}
+
+static int airspy_kill_urbs(struct airspy *s)
+{
+	int i;
+
+	for (i = s->urbs_submitted - 1; i >= 0; i--) {
+		dev_dbg(&s->udev->dev, "%s: kill urb=%d\n", __func__, i);
+		/* stop the URB */
+		usb_kill_urb(s->urb_list[i]);
+	}
+	s->urbs_submitted = 0;
+
+	return 0;
+}
+
+static int airspy_submit_urbs(struct airspy *s)
+{
+	int i, ret;
+
+	for (i = 0; i < s->urbs_initialized; i++) {
+		dev_dbg(&s->udev->dev, "%s: submit urb=%d\n", __func__, i);
+		ret = usb_submit_urb(s->urb_list[i], GFP_ATOMIC);
+		if (ret) {
+			dev_err(&s->udev->dev,
+					"Could not submit URB no. %d - get them all back\n",
+					i);
+			airspy_kill_urbs(s);
+			return ret;
+		}
+		s->urbs_submitted++;
+	}
+
+	return 0;
+}
+
+static int airspy_free_stream_bufs(struct airspy *s)
+{
+	if (s->flags & USB_STATE_URB_BUF) {
+		while (s->buf_num) {
+			s->buf_num--;
+			dev_dbg(&s->udev->dev, "%s: free buf=%d\n",
+					__func__, s->buf_num);
+			usb_free_coherent(s->udev, s->buf_size,
+					  s->buf_list[s->buf_num],
+					  s->dma_addr[s->buf_num]);
+		}
+	}
+	s->flags &= ~USB_STATE_URB_BUF;
+
+	return 0;
+}
+
+static int airspy_alloc_stream_bufs(struct airspy *s)
+{
+	s->buf_num = 0;
+	s->buf_size = BULK_BUFFER_SIZE;
+
+	dev_dbg(&s->udev->dev,
+			"%s: all in all I will use %u bytes for streaming\n",
+			__func__,  MAX_BULK_BUFS * BULK_BUFFER_SIZE);
+
+	for (s->buf_num = 0; s->buf_num < MAX_BULK_BUFS; s->buf_num++) {
+		s->buf_list[s->buf_num] = usb_alloc_coherent(s->udev,
+				BULK_BUFFER_SIZE, GFP_ATOMIC,
+				&s->dma_addr[s->buf_num]);
+		if (!s->buf_list[s->buf_num]) {
+			dev_dbg(&s->udev->dev, "%s: alloc buf=%d failed\n",
+					__func__, s->buf_num);
+			airspy_free_stream_bufs(s);
+			return -ENOMEM;
+		}
+
+		dev_dbg(&s->udev->dev, "%s: alloc buf=%d %p (dma %llu)\n",
+				__func__, s->buf_num,
+				s->buf_list[s->buf_num],
+				(long long)s->dma_addr[s->buf_num]);
+		s->flags |= USB_STATE_URB_BUF;
+	}
+
+	return 0;
+}
+
+static int airspy_free_urbs(struct airspy *s)
+{
+	int i;
+
+	airspy_kill_urbs(s);
+
+	for (i = s->urbs_initialized - 1; i >= 0; i--) {
+		if (s->urb_list[i]) {
+			dev_dbg(&s->udev->dev, "%s: free urb=%d\n",
+					__func__, i);
+			/* free the URBs */
+			usb_free_urb(s->urb_list[i]);
+		}
+	}
+	s->urbs_initialized = 0;
+
+	return 0;
+}
+
+static int airspy_alloc_urbs(struct airspy *s)
+{
+	int i, j;
+
+	/* allocate the URBs */
+	for (i = 0; i < MAX_BULK_BUFS; i++) {
+		dev_dbg(&s->udev->dev, "%s: alloc urb=%d\n", __func__, i);
+		s->urb_list[i] = usb_alloc_urb(0, GFP_ATOMIC);
+		if (!s->urb_list[i]) {
+			dev_dbg(&s->udev->dev, "%s: failed\n", __func__);
+			for (j = 0; j < i; j++)
+				usb_free_urb(s->urb_list[j]);
+			return -ENOMEM;
+		}
+		usb_fill_bulk_urb(s->urb_list[i],
+				s->udev,
+				usb_rcvbulkpipe(s->udev, 0x81),
+				s->buf_list[i],
+				BULK_BUFFER_SIZE,
+				airspy_urb_complete, s);
+
+		s->urb_list[i]->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
+		s->urb_list[i]->transfer_dma = s->dma_addr[i];
+		s->urbs_initialized++;
+	}
+
+	return 0;
+}
+
+/* Must be called with vb_queue_lock hold */
+static void airspy_cleanup_queued_bufs(struct airspy *s)
+{
+	unsigned long flags = 0;
+
+	dev_dbg(&s->udev->dev, "%s:\n", __func__);
+
+	spin_lock_irqsave(&s->queued_bufs_lock, flags);
+	while (!list_empty(&s->queued_bufs)) {
+		struct airspy_frame_buf *buf;
+		buf = list_entry(s->queued_bufs.next,
+				struct airspy_frame_buf, list);
+		list_del(&buf->list);
+		vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
+	}
+	spin_unlock_irqrestore(&s->queued_bufs_lock, flags);
+}
+
+/* The user yanked out the cable... */
+static void airspy_disconnect(struct usb_interface *intf)
+{
+	struct v4l2_device *v = usb_get_intfdata(intf);
+	struct airspy *s = container_of(v, struct airspy, v4l2_dev);
+
+	dev_dbg(&s->udev->dev, "%s:\n", __func__);
+
+	mutex_lock(&s->vb_queue_lock);
+	mutex_lock(&s->v4l2_lock);
+	/* No need to keep the urbs around after disconnection */
+	s->udev = NULL;
+	v4l2_device_disconnect(&s->v4l2_dev);
+	video_unregister_device(&s->vdev);
+	mutex_unlock(&s->v4l2_lock);
+	mutex_unlock(&s->vb_queue_lock);
+
+	v4l2_device_put(&s->v4l2_dev);
+}
+
+/* Videobuf2 operations */
+static int airspy_queue_setup(struct vb2_queue *vq,
+		const struct v4l2_format *fmt, unsigned int *nbuffers,
+		unsigned int *nplanes, unsigned int sizes[], void *alloc_ctxs[])
+{
+	struct airspy *s = vb2_get_drv_priv(vq);
+
+	dev_dbg(&s->udev->dev, "%s: *nbuffers=%d\n", __func__, *nbuffers);
+
+	/* Need at least 8 buffers */
+	if (vq->num_buffers + *nbuffers < 8)
+		*nbuffers = 8 - vq->num_buffers;
+	*nplanes = 1;
+	sizes[0] = PAGE_ALIGN(BULK_BUFFER_SIZE);
+
+	dev_dbg(&s->udev->dev, "%s: nbuffers=%d sizes[0]=%d\n",
+			__func__, *nbuffers, sizes[0]);
+	return 0;
+}
+
+static void airspy_buf_queue(struct vb2_buffer *vb)
+{
+	struct airspy *s = vb2_get_drv_priv(vb->vb2_queue);
+	struct airspy_frame_buf *buf =
+			container_of(vb, struct airspy_frame_buf, vb);
+	unsigned long flags = 0;
+
+	/* Check the device has not disconnected between prep and queuing */
+	if (unlikely(!s->udev)) {
+		vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
+		return;
+	}
+
+	spin_lock_irqsave(&s->queued_bufs_lock, flags);
+	list_add_tail(&buf->list, &s->queued_bufs);
+	spin_unlock_irqrestore(&s->queued_bufs_lock, flags);
+}
+
+static int airspy_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+	struct airspy *s = vb2_get_drv_priv(vq);
+	int ret;
+
+	dev_dbg(&s->udev->dev, "%s:\n", __func__);
+
+	if (!s->udev)
+		return -ENODEV;
+
+	mutex_lock(&s->v4l2_lock);
+
+	set_bit(POWER_ON, &s->flags);
+
+	s->sequence = 0;
+
+	ret = airspy_alloc_stream_bufs(s);
+	if (ret)
+		goto err;
+
+	ret = airspy_alloc_urbs(s);
+	if (ret)
+		goto err;
+
+	ret = airspy_submit_urbs(s);
+	if (ret)
+		goto err;
+
+	/* start hardware streaming */
+	ret = airspy_ctrl_msg(s, CMD_RECEIVER_MODE, 1, 0, NULL, 0);
+	if (ret)
+		goto err;
+err:
+	mutex_unlock(&s->v4l2_lock);
+
+	return ret;
+}
+
+static void airspy_stop_streaming(struct vb2_queue *vq)
+{
+	struct airspy *s = vb2_get_drv_priv(vq);
+	int ret;
+
+	dev_dbg(&s->udev->dev, "%s:\n", __func__);
+
+	mutex_lock(&s->v4l2_lock);
+
+	/* stop hardware streaming */
+	ret = airspy_ctrl_msg(s, CMD_RECEIVER_MODE, 0, 0, NULL, 0);
+
+	airspy_kill_urbs(s);
+	airspy_free_urbs(s);
+	airspy_free_stream_bufs(s);
+
+	airspy_cleanup_queued_bufs(s);
+
+	clear_bit(POWER_ON, &s->flags);
+
+	mutex_unlock(&s->v4l2_lock);
+}
+
+static struct vb2_ops airspy_vb2_ops = {
+	.queue_setup            = airspy_queue_setup,
+	.buf_queue              = airspy_buf_queue,
+	.start_streaming        = airspy_start_streaming,
+	.stop_streaming         = airspy_stop_streaming,
+	.wait_prepare           = vb2_ops_wait_prepare,
+	.wait_finish            = vb2_ops_wait_finish,
+};
+
+static int airspy_querycap(struct file *file, void *fh,
+		struct v4l2_capability *cap)
+{
+	struct airspy *s = video_drvdata(file);
+
+	dev_dbg(&s->udev->dev, "%s:\n", __func__);
+
+	strlcpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
+	strlcpy(cap->card, s->vdev.name, sizeof(cap->card));
+	usb_make_path(s->udev, cap->bus_info, sizeof(cap->bus_info));
+	cap->device_caps = V4L2_CAP_SDR_CAPTURE | V4L2_CAP_STREAMING |
+			V4L2_CAP_READWRITE | V4L2_CAP_TUNER;
+	cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
+
+	return 0;
+}
+
+static int airspy_enum_fmt_sdr_cap(struct file *file, void *priv,
+		struct v4l2_fmtdesc *f)
+{
+	struct airspy *s = video_drvdata(file);
+
+	dev_dbg(&s->udev->dev, "%s: index=%d\n", __func__, f->index);
+
+	if (f->index >= NUM_FORMATS)
+		return -EINVAL;
+
+	strlcpy(f->description, formats[f->index].name, sizeof(f->description));
+	f->pixelformat = formats[f->index].pixelformat;
+
+	return 0;
+}
+
+static int airspy_g_fmt_sdr_cap(struct file *file, void *priv,
+		struct v4l2_format *f)
+{
+	struct airspy *s = video_drvdata(file);
+
+	dev_dbg(&s->udev->dev, "%s: pixelformat fourcc %4.4s\n", __func__,
+			(char *)&s->pixelformat);
+
+	memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
+	f->fmt.sdr.pixelformat = s->pixelformat;
+
+	return 0;
+}
+
+static int airspy_s_fmt_sdr_cap(struct file *file, void *priv,
+		struct v4l2_format *f)
+{
+	struct airspy *s = video_drvdata(file);
+	struct vb2_queue *q = &s->vb_queue;
+	int i;
+
+	dev_dbg(&s->udev->dev, "%s: pixelformat fourcc %4.4s\n", __func__,
+			(char *)&f->fmt.sdr.pixelformat);
+
+	if (vb2_is_busy(q))
+		return -EBUSY;
+
+	memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
+	for (i = 0; i < NUM_FORMATS; i++) {
+		if (formats[i].pixelformat == f->fmt.sdr.pixelformat) {
+			s->pixelformat = f->fmt.sdr.pixelformat;
+			return 0;
+		}
+	}
+
+	f->fmt.sdr.pixelformat = formats[0].pixelformat;
+	s->pixelformat = formats[0].pixelformat;
+
+	return 0;
+}
+
+static int airspy_try_fmt_sdr_cap(struct file *file, void *priv,
+		struct v4l2_format *f)
+{
+	struct airspy *s = video_drvdata(file);
+	int i;
+
+	dev_dbg(&s->udev->dev, "%s: pixelformat fourcc %4.4s\n", __func__,
+			(char *)&f->fmt.sdr.pixelformat);
+
+	memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
+	for (i = 0; i < NUM_FORMATS; i++) {
+		if (formats[i].pixelformat == f->fmt.sdr.pixelformat)
+			return 0;
+	}
+
+	f->fmt.sdr.pixelformat = formats[0].pixelformat;
+
+	return 0;
+}
+
+static int airspy_s_tuner(struct file *file, void *priv,
+		const struct v4l2_tuner *v)
+{
+	struct airspy *s = video_drvdata(file);
+	int ret;
+
+	dev_dbg(&s->udev->dev, "%s: index=%d\n", __func__, v->index);
+
+	if (v->index == 0)
+		ret = 0;
+	else if (v->index == 1)
+		ret = 0;
+	else
+		ret = -EINVAL;
+
+	return ret;
+}
+
+static int airspy_g_tuner(struct file *file, void *priv, struct v4l2_tuner *v)
+{
+	struct airspy *s = video_drvdata(file);
+	int ret;
+
+	dev_dbg(&s->udev->dev, "%s: index=%d\n", __func__, v->index);
+
+	if (v->index == 0) {
+		strlcpy(v->name, "AirSpy ADC", sizeof(v->name));
+		v->type = V4L2_TUNER_ADC;
+		v->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
+		v->rangelow  = bands[0].rangelow;
+		v->rangehigh = bands[0].rangehigh;
+		ret = 0;
+	} else if (v->index == 1) {
+		strlcpy(v->name, "AirSpy RF", sizeof(v->name));
+		v->type = V4L2_TUNER_RF;
+		v->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
+		v->rangelow  = bands_rf[0].rangelow;
+		v->rangehigh = bands_rf[0].rangehigh;
+		ret = 0;
+	} else {
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int airspy_g_frequency(struct file *file, void *priv,
+		struct v4l2_frequency *f)
+{
+	struct airspy *s = video_drvdata(file);
+	int ret  = 0;
+	dev_dbg(&s->udev->dev, "%s: tuner=%d type=%d\n",
+			__func__, f->tuner, f->type);
+
+	if (f->tuner == 0) {
+		f->type = V4L2_TUNER_ADC;
+		f->frequency = s->f_adc;
+		ret = 0;
+	} else if (f->tuner == 1) {
+		f->type = V4L2_TUNER_RF;
+		f->frequency = s->f_rf;
+	} else {
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int airspy_s_frequency(struct file *file, void *priv,
+		const struct v4l2_frequency *f)
+{
+	struct airspy *s = video_drvdata(file);
+	int ret;
+	u8 buf[4];
+
+	dev_dbg(&s->udev->dev, "%s: tuner=%d type=%d frequency=%u\n",
+			__func__, f->tuner, f->type, f->frequency);
+
+	if (f->tuner == 0) {
+		s->f_adc = clamp_t(unsigned int, f->frequency,
+				bands[0].rangelow,
+				bands[0].rangehigh);
+		dev_dbg(&s->udev->dev, "%s: ADC frequency=%u Hz\n",
+				__func__, s->f_adc);
+		ret = 0;
+	} else if (f->tuner == 1) {
+		s->f_rf = clamp_t(unsigned int, f->frequency,
+				bands_rf[0].rangelow,
+				bands_rf[0].rangehigh);
+		dev_dbg(&s->udev->dev, "%s: RF frequency=%u Hz\n",
+				__func__, s->f_rf);
+		buf[0] = (s->f_rf >>  0) & 0xff;
+		buf[1] = (s->f_rf >>  8) & 0xff;
+		buf[2] = (s->f_rf >> 16) & 0xff;
+		buf[3] = (s->f_rf >> 24) & 0xff;
+		ret = airspy_ctrl_msg(s, CMD_SET_FREQ, 0, 0, buf, 4);
+	} else {
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int airspy_enum_freq_bands(struct file *file, void *priv,
+		struct v4l2_frequency_band *band)
+{
+	struct airspy *s = video_drvdata(file);
+	int ret;
+	dev_dbg(&s->udev->dev, "%s: tuner=%d type=%d index=%d\n",
+			__func__, band->tuner, band->type, band->index);
+
+	if (band->tuner == 0) {
+		if (band->index >= ARRAY_SIZE(bands)) {
+			ret = -EINVAL;
+		} else {
+			*band = bands[band->index];
+			ret = 0;
+		}
+	} else if (band->tuner == 1) {
+		if (band->index >= ARRAY_SIZE(bands_rf)) {
+			ret = -EINVAL;
+		} else {
+			*band = bands_rf[band->index];
+			ret = 0;
+		}
+	} else {
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static const struct v4l2_ioctl_ops airspy_ioctl_ops = {
+	.vidioc_querycap          = airspy_querycap,
+
+	.vidioc_enum_fmt_sdr_cap  = airspy_enum_fmt_sdr_cap,
+	.vidioc_g_fmt_sdr_cap     = airspy_g_fmt_sdr_cap,
+	.vidioc_s_fmt_sdr_cap     = airspy_s_fmt_sdr_cap,
+	.vidioc_try_fmt_sdr_cap   = airspy_try_fmt_sdr_cap,
+
+	.vidioc_reqbufs           = vb2_ioctl_reqbufs,
+	.vidioc_create_bufs       = vb2_ioctl_create_bufs,
+	.vidioc_prepare_buf       = vb2_ioctl_prepare_buf,
+	.vidioc_querybuf          = vb2_ioctl_querybuf,
+	.vidioc_qbuf              = vb2_ioctl_qbuf,
+	.vidioc_dqbuf             = vb2_ioctl_dqbuf,
+
+	.vidioc_streamon          = vb2_ioctl_streamon,
+	.vidioc_streamoff         = vb2_ioctl_streamoff,
+
+	.vidioc_g_tuner           = airspy_g_tuner,
+	.vidioc_s_tuner           = airspy_s_tuner,
+
+	.vidioc_g_frequency       = airspy_g_frequency,
+	.vidioc_s_frequency       = airspy_s_frequency,
+	.vidioc_enum_freq_bands   = airspy_enum_freq_bands,
+
+	.vidioc_subscribe_event   = v4l2_ctrl_subscribe_event,
+	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
+	.vidioc_log_status        = v4l2_ctrl_log_status,
+};
+
+static const struct v4l2_file_operations airspy_fops = {
+	.owner                    = THIS_MODULE,
+	.open                     = v4l2_fh_open,
+	.release                  = vb2_fop_release,
+	.read                     = vb2_fop_read,
+	.poll                     = vb2_fop_poll,
+	.mmap                     = vb2_fop_mmap,
+	.unlocked_ioctl           = video_ioctl2,
+};
+
+static struct video_device airspy_template = {
+	.name                     = "AirSpy SDR",
+	.release                  = video_device_release_empty,
+	.fops                     = &airspy_fops,
+	.ioctl_ops                = &airspy_ioctl_ops,
+};
+
+static void airspy_video_release(struct v4l2_device *v)
+{
+	struct airspy *s = container_of(v, struct airspy, v4l2_dev);
+
+	v4l2_ctrl_handler_free(&s->hdl);
+	v4l2_device_unregister(&s->v4l2_dev);
+	kfree(s);
+}
+
+static int airspy_set_lna_gain(struct airspy *s)
+{
+	int ret;
+	u8 u8tmp;
+
+	dev_dbg(&s->udev->dev, "%s: lna auto=%d->%d val=%d->%d\n",
+			__func__, s->lna_gain_auto->cur.val,
+			s->lna_gain_auto->val, s->lna_gain->cur.val,
+			s->lna_gain->val);
+
+	ret = airspy_ctrl_msg(s, CMD_SET_LNA_AGC, 0, s->lna_gain_auto->val,
+			&u8tmp, 1);
+	if (ret)
+		goto err;
+
+	if (s->lna_gain_auto->val == false) {
+		ret = airspy_ctrl_msg(s, CMD_SET_LNA_GAIN, 0, s->lna_gain->val,
+				&u8tmp, 1);
+		if (ret)
+			goto err;
+	}
+err:
+	if (ret)
+		dev_dbg(&s->udev->dev, "%s: failed=%d\n", __func__, ret);
+
+	return ret;
+}
+
+static int airspy_set_mixer_gain(struct airspy *s)
+{
+	int ret;
+	u8 u8tmp;
+
+	dev_dbg(&s->udev->dev, "%s: mixer auto=%d->%d val=%d->%d\n",
+			__func__, s->mixer_gain_auto->cur.val,
+			s->mixer_gain_auto->val, s->mixer_gain->cur.val,
+			s->mixer_gain->val);
+
+	ret = airspy_ctrl_msg(s, CMD_SET_MIXER_AGC, 0, s->mixer_gain_auto->val,
+			&u8tmp, 1);
+	if (ret)
+		goto err;
+
+	if (s->mixer_gain_auto->val == false) {
+		ret = airspy_ctrl_msg(s, CMD_SET_MIXER_GAIN, 0,
+				s->mixer_gain->val, &u8tmp, 1);
+		if (ret)
+			goto err;
+	}
+err:
+	if (ret)
+		dev_dbg(&s->udev->dev, "%s: failed=%d\n", __func__, ret);
+
+	return ret;
+}
+
+static int airspy_set_if_gain(struct airspy *s)
+{
+	int ret;
+	u8 u8tmp;
+
+	dev_dbg(&s->udev->dev, "%s: val=%d->%d\n",
+			__func__, s->if_gain->cur.val, s->if_gain->val);
+
+	ret = airspy_ctrl_msg(s, CMD_SET_VGA_GAIN, 0, s->if_gain->val,
+			&u8tmp, 1);
+	if (ret)
+		goto err;
+err:
+	if (ret)
+		dev_dbg(&s->udev->dev, "%s: failed=%d\n", __func__, ret);
+
+	return ret;
+}
+
+static int airspy_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct airspy *s = container_of(ctrl->handler, struct airspy, hdl);
+	int ret;
+
+	switch (ctrl->id) {
+	case  V4L2_CID_RF_TUNER_LNA_GAIN_AUTO:
+	case  V4L2_CID_RF_TUNER_LNA_GAIN:
+		ret = airspy_set_lna_gain(s);
+		break;
+	case  V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO:
+	case  V4L2_CID_RF_TUNER_MIXER_GAIN:
+		ret = airspy_set_mixer_gain(s);
+		break;
+	case  V4L2_CID_RF_TUNER_IF_GAIN:
+		ret = airspy_set_if_gain(s);
+		break;
+	default:
+		dev_dbg(&s->udev->dev, "%s: unknown ctrl: id=%d name=%s\n",
+				__func__, ctrl->id, ctrl->name);
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static const struct v4l2_ctrl_ops airspy_ctrl_ops = {
+	.s_ctrl = airspy_s_ctrl,
+};
+
+static int airspy_probe(struct usb_interface *intf,
+		const struct usb_device_id *id)
+{
+	struct usb_device *udev = interface_to_usbdev(intf);
+	struct airspy *s = NULL;
+	int ret;
+	u8 u8tmp, buf[BUF_SIZE];
+
+	s = kzalloc(sizeof(struct airspy), GFP_KERNEL);
+	if (s == NULL) {
+		dev_err(&udev->dev,
+				"Could not allocate memory for airspy state\n");
+		return -ENOMEM;
+	}
+
+	mutex_init(&s->v4l2_lock);
+	mutex_init(&s->vb_queue_lock);
+	spin_lock_init(&s->queued_bufs_lock);
+	INIT_LIST_HEAD(&s->queued_bufs);
+	s->udev = udev;
+	s->f_adc = bands[0].rangelow;
+	s->f_rf = bands_rf[0].rangelow;
+	s->pixelformat = V4L2_SDR_FMT_RU12LE;
+
+	/* Detect device */
+	ret = airspy_ctrl_msg(s, CMD_BOARD_ID_READ, 0, 0, &u8tmp, 1);
+	if (ret == 0)
+		ret = airspy_ctrl_msg(s, CMD_VERSION_STRING_READ, 0, 0,
+				buf, BUF_SIZE);
+	if (ret) {
+		dev_err(&s->udev->dev, "Could not detect board\n");
+		goto err_free_mem;
+	}
+
+	buf[BUF_SIZE - 1] = '\0';
+
+	dev_info(&s->udev->dev, "Board ID: %02x\n", u8tmp);
+	dev_info(&s->udev->dev, "Firmware version: %s\n", buf);
+
+	/* Init videobuf2 queue structure */
+	s->vb_queue.type = V4L2_BUF_TYPE_SDR_CAPTURE;
+	s->vb_queue.io_modes = VB2_MMAP | VB2_USERPTR | VB2_READ;
+	s->vb_queue.drv_priv = s;
+	s->vb_queue.buf_struct_size = sizeof(struct airspy_frame_buf);
+	s->vb_queue.ops = &airspy_vb2_ops;
+	s->vb_queue.mem_ops = &vb2_vmalloc_memops;
+	s->vb_queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+	ret = vb2_queue_init(&s->vb_queue);
+	if (ret) {
+		dev_err(&s->udev->dev, "Could not initialize vb2 queue\n");
+		goto err_free_mem;
+	}
+
+	/* Init video_device structure */
+	s->vdev = airspy_template;
+	s->vdev.queue = &s->vb_queue;
+	s->vdev.queue->lock = &s->vb_queue_lock;
+	set_bit(V4L2_FL_USE_FH_PRIO, &s->vdev.flags);
+	video_set_drvdata(&s->vdev, s);
+
+	/* Register the v4l2_device structure */
+	s->v4l2_dev.release = airspy_video_release;
+	ret = v4l2_device_register(&intf->dev, &s->v4l2_dev);
+	if (ret) {
+		dev_err(&s->udev->dev,
+				"Failed to register v4l2-device (%d)\n", ret);
+		goto err_free_mem;
+	}
+
+	/* Register controls */
+	v4l2_ctrl_handler_init(&s->hdl, 5);
+	s->lna_gain_auto = v4l2_ctrl_new_std(&s->hdl, &airspy_ctrl_ops,
+			V4L2_CID_RF_TUNER_LNA_GAIN_AUTO, 0, 1, 1, 0);
+	s->lna_gain = v4l2_ctrl_new_std(&s->hdl, &airspy_ctrl_ops,
+			V4L2_CID_RF_TUNER_LNA_GAIN, 0, 14, 1, 8);
+	v4l2_ctrl_auto_cluster(2, &s->lna_gain_auto, 0, false);
+	s->mixer_gain_auto = v4l2_ctrl_new_std(&s->hdl, &airspy_ctrl_ops,
+			V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO, 0, 1, 1, 0);
+	s->mixer_gain = v4l2_ctrl_new_std(&s->hdl, &airspy_ctrl_ops,
+			V4L2_CID_RF_TUNER_MIXER_GAIN, 0, 15, 1, 8);
+	v4l2_ctrl_auto_cluster(2, &s->mixer_gain_auto, 0, false);
+	s->if_gain = v4l2_ctrl_new_std(&s->hdl, &airspy_ctrl_ops,
+			V4L2_CID_RF_TUNER_IF_GAIN, 0, 15, 1, 0);
+	if (s->hdl.error) {
+		ret = s->hdl.error;
+		dev_err(&s->udev->dev, "Could not initialize controls\n");
+		goto err_free_controls;
+	}
+
+	v4l2_ctrl_handler_setup(&s->hdl);
+
+	s->v4l2_dev.ctrl_handler = &s->hdl;
+	s->vdev.v4l2_dev = &s->v4l2_dev;
+	s->vdev.lock = &s->v4l2_lock;
+
+	ret = video_register_device(&s->vdev, VFL_TYPE_SDR, -1);
+	if (ret) {
+		dev_err(&s->udev->dev,
+				"Failed to register as video device (%d)\n",
+				ret);
+		goto err_unregister_v4l2_dev;
+	}
+	dev_info(&s->udev->dev, "Registered as %s\n",
+			video_device_node_name(&s->vdev));
+
+	return 0;
+
+err_free_controls:
+	v4l2_ctrl_handler_free(&s->hdl);
+err_unregister_v4l2_dev:
+	v4l2_device_unregister(&s->v4l2_dev);
+err_free_mem:
+	kfree(s);
+	return ret;
+}
+
+/* USB device ID list */
+static struct usb_device_id airspy_id_table[] = {
+	{ USB_DEVICE(0x1d50, 0x60a1) }, /* AirSpy */
+	{ }
+};
+MODULE_DEVICE_TABLE(usb, airspy_id_table);
+
+/* USB subsystem interface */
+static struct usb_driver airspy_driver = {
+	.name                     = KBUILD_MODNAME,
+	.probe                    = airspy_probe,
+	.disconnect               = airspy_disconnect,
+	.id_table                 = airspy_id_table,
+};
+
+module_usb_driver(airspy_driver);
+
+MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
+MODULE_DESCRIPTION("AirSpy SDR");
+MODULE_LICENSE("GPL");