[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: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

5 files changed, 1128 insertions, 0 deletions

diff --git a/drivers/staging/media/Kconfig b/drivers/staging/media/Kconfig
index cd2af3769f7f..5942414d3a04 100644
--- a/drivers/staging/media/Kconfig
+++ b/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"
diff --git a/drivers/staging/media/Makefile b/drivers/staging/media/Makefile
index 2766a3e9e053..730c2659cccd 100644
--- a/drivers/staging/media/Makefile
+++ b/drivers/staging/media/Makefile
@@ -1,3 +1,4 @@
+obj-$(CONFIG_USB_AIRSPY)        += airspy/
 obj-$(CONFIG_DVB_AS102)         += as102/
 obj-$(CONFIG_I2C_BCM2048)       += bcm2048/
 obj-$(CONFIG_DVB_CXD2099)       += cxd2099/
diff --git a/drivers/staging/media/airspy/Kconfig b/drivers/staging/media/airspy/Kconfig
new file mode 100644
index 000000000000..59a829b19e79
--- /dev/null
+++ b/drivers/staging/media/airspy/Kconfig
@@ -0,0 +1,5 @@
+config USB_AIRSPY
+        tristate "AirSpy"
+        depends on USB && VIDEO_DEV && VIDEO_V4L2 && I2C
+        select VIDEOBUF2_VMALLOC
+        default m if !MEDIA_SUBDRV_AUTOSELECT
diff --git a/drivers/staging/media/airspy/Makefile b/drivers/staging/media/airspy/Makefile
new file mode 100644
index 000000000000..8d8e61c1a349
--- /dev/null
+++ b/drivers/staging/media/airspy/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_USB_AIRSPY)              += airspy.o
diff --git a/drivers/staging/media/airspy/airspy.c b/drivers/staging/media/airspy/airspy.c
new file mode 100644
index 000000000000..daecd91bce37
--- /dev/null
+++ b/drivers/staging/media/airspy/airspy.c
@@ -0,0 +1,1120 @@
+/*
+ * 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");