root/drivers/media/dvb-frontends/rtl2832_sdr.c 
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Realtek RTL2832U SDR driver
 *
 * Copyright (C) 2013 Antti Palosaari <crope@iki.fi>
 *
 * GNU Radio plugin "gr-kernel" for device usage will be on:
 * https://git.linuxtv.org/anttip/gr-kernel.git
 */

#include "rtl2832_sdr.h"
#include "dvb_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-v4l2.h>
#include <media/videobuf2-vmalloc.h>

#include <linux/platform_device.h>
#include <linux/jiffies.h>
#include <linux/math64.h>
#include <linux/regmap.h>

static bool rtl2832_sdr_emulated_fmt;
module_param_named(emulated_formats, rtl2832_sdr_emulated_fmt, bool, 0644);
MODULE_PARM_DESC(emulated_formats, "enable emulated formats (disappears in future)");

/* Original macro does not contain enough null pointer checks for our need */
#define V4L2_SUBDEV_HAS_OP(sd, o, f) \
        ((sd) && (sd)->ops && (sd)->ops->o && (sd)->ops->o->f)

#define MAX_BULK_BUFS            (10)
#define BULK_BUFFER_SIZE         (128 * 512)

static const struct v4l2_frequency_band bands_adc[] = {
        {
                .tuner = 0,
                .type = V4L2_TUNER_ADC,
                .index = 0,
                .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
                .rangelow   =  300000,
                .rangehigh  =  300000,
        },
        {
                .tuner = 0,
                .type = V4L2_TUNER_ADC,
                .index = 1,
                .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
                .rangelow   =  900001,
                .rangehigh  = 2800000,
        },
        {
                .tuner = 0,
                .type = V4L2_TUNER_ADC,
                .index = 2,
                .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
                .rangelow   = 3200000,
                .rangehigh  = 3200000,
        },
};

static const struct v4l2_frequency_band bands_fm[] = {
        {
                .tuner = 1,
                .type = V4L2_TUNER_RF,
                .index = 0,
                .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
                .rangelow   =    50000000,
                .rangehigh  =  2000000000,
        },
};

/* stream formats */
struct rtl2832_sdr_format {
        char    *name;
        u32     pixelformat;
        u32     buffersize;
};

static struct rtl2832_sdr_format formats[] = {
        {
                .pixelformat    = V4L2_SDR_FMT_CU8,
                .buffersize     = BULK_BUFFER_SIZE,
        }, {
                .pixelformat    = V4L2_SDR_FMT_CU16LE,
                .buffersize     = BULK_BUFFER_SIZE * 2,
        },
};

static const unsigned int NUM_FORMATS = ARRAY_SIZE(formats);

/* intermediate buffers with raw data from the USB device */
struct rtl2832_sdr_frame_buf {
        /* common v4l buffer stuff -- must be first */
        struct vb2_v4l2_buffer vb;
        struct list_head list;
};

struct rtl2832_sdr_dev {
#define POWER_ON           0  /* BIT(0) */
#define URB_BUF            1  /* BIT(1) */
        unsigned long flags;

        struct platform_device *pdev;
        struct regmap *regmap;

        struct video_device vdev;
        struct v4l2_device v4l2_dev;
        struct v4l2_subdev *v4l2_subdev;

        /* 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 */

        /* 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 */

        /* Pointer to our usb_device, will be NULL after unplug */
        struct usb_device *udev; /* Both mutexes most be hold when setting! */

        unsigned int vb_full; /* vb is full and packets dropped */

        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;

        unsigned int f_adc, f_tuner;
        u32 pixelformat;
        u32 buffersize;
        unsigned int num_formats;

        /* Controls */
        struct v4l2_ctrl_handler hdl;
        struct v4l2_ctrl *bandwidth_auto;
        struct v4l2_ctrl *bandwidth;

        /* for sample rate calc */
        unsigned int sample;
        unsigned int sample_measured;
        unsigned long jiffies_next;
};

/* Private functions */
static struct rtl2832_sdr_frame_buf *rtl2832_sdr_get_next_fill_buf(
                struct rtl2832_sdr_dev *dev)
{
        unsigned long flags;
        struct rtl2832_sdr_frame_buf *buf = NULL;

        spin_lock_irqsave(&dev->queued_bufs_lock, flags);
        if (list_empty(&dev->queued_bufs))
                goto leave;

        buf = list_entry(dev->queued_bufs.next,
                        struct rtl2832_sdr_frame_buf, list);
        list_del(&buf->list);
leave:
        spin_unlock_irqrestore(&dev->queued_bufs_lock, flags);
        return buf;
}

static unsigned int rtl2832_sdr_convert_stream(struct rtl2832_sdr_dev *dev,
                void *dst, const u8 *src, unsigned int src_len)
{
        struct platform_device *pdev = dev->pdev;
        unsigned int dst_len;

        if (dev->pixelformat ==  V4L2_SDR_FMT_CU8) {
                /* native stream, no need to convert */
                memcpy(dst, src, src_len);
                dst_len = src_len;
        } else if (dev->pixelformat == V4L2_SDR_FMT_CU16LE) {
                /* convert u8 to u16 */
                unsigned int i;
                u16 *u16dst = dst;

                for (i = 0; i < src_len; i++)
                        *u16dst++ = (src[i] << 8) | (src[i] >> 0);
                dst_len = 2 * src_len;
        } else {
                dst_len = 0;
        }

        /* calculate sample rate and output it in 10 seconds intervals */
        if (unlikely(time_is_before_jiffies(dev->jiffies_next))) {
                #define MSECS 10000UL
                unsigned int msecs = jiffies_to_msecs(jiffies -
                                dev->jiffies_next + msecs_to_jiffies(MSECS));
                unsigned int samples = dev->sample - dev->sample_measured;

                dev->jiffies_next = jiffies + msecs_to_jiffies(MSECS);
                dev->sample_measured = dev->sample;
                dev_dbg(&pdev->dev,
                        "slen=%u samples=%u msecs=%u sample rate=%lu\n",
                        src_len, samples, msecs, samples * 1000UL / msecs);
        }

        /* total number of I+Q pairs */
        dev->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 rtl2832_sdr_urb_complete(struct urb *urb)
{
        struct rtl2832_sdr_dev *dev = urb->context;
        struct platform_device *pdev = dev->pdev;
        struct rtl2832_sdr_frame_buf *fbuf;

        dev_dbg_ratelimited(&pdev->dev, "status=%d length=%d/%d errors=%d\n",
                            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(&pdev->dev, "urb failed=%d\n", urb->status);
                break;
        }

        if (likely(urb->actual_length > 0)) {
                void *ptr;
                unsigned int len;
                /* get free framebuffer */
                fbuf = rtl2832_sdr_get_next_fill_buf(dev);
                if (unlikely(fbuf == NULL)) {
                        dev->vb_full++;
                        dev_notice_ratelimited(&pdev->dev,
                                               "video buffer is full, %d packets dropped\n",
                                               dev->vb_full);
                        goto skip;
                }

                /* fill framebuffer */
                ptr = vb2_plane_vaddr(&fbuf->vb.vb2_buf, 0);
                len = rtl2832_sdr_convert_stream(dev, ptr, urb->transfer_buffer,
                                urb->actual_length);
                vb2_set_plane_payload(&fbuf->vb.vb2_buf, 0, len);
                fbuf->vb.vb2_buf.timestamp = ktime_get_ns();
                fbuf->vb.sequence = dev->sequence++;
                vb2_buffer_done(&fbuf->vb.vb2_buf, VB2_BUF_STATE_DONE);
        }
skip:
        usb_submit_urb(urb, GFP_ATOMIC);
}

static int rtl2832_sdr_kill_urbs(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;
        int i;

        for (i = dev->urbs_submitted - 1; i >= 0; i--) {
                dev_dbg(&pdev->dev, "kill urb=%d\n", i);
                /* stop the URB */
                usb_kill_urb(dev->urb_list[i]);
        }
        dev->urbs_submitted = 0;

        return 0;
}

static int rtl2832_sdr_submit_urbs(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;
        int i, ret;

        for (i = 0; i < dev->urbs_initialized; i++) {
                dev_dbg(&pdev->dev, "submit urb=%d\n", i);
                ret = usb_submit_urb(dev->urb_list[i], GFP_KERNEL);
                if (ret) {
                        dev_err(&pdev->dev,
                                "Could not submit urb no. %d - get them all back\n",
                                i);
                        rtl2832_sdr_kill_urbs(dev);
                        return ret;
                }
                dev->urbs_submitted++;
        }

        return 0;
}

static int rtl2832_sdr_free_stream_bufs(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;

        if (test_bit(URB_BUF, &dev->flags)) {
                while (dev->buf_num) {
                        dev->buf_num--;
                        dev_dbg(&pdev->dev, "free buf=%d\n", dev->buf_num);
                        usb_free_coherent(dev->udev, dev->buf_size,
                                          dev->buf_list[dev->buf_num],
                                          dev->dma_addr[dev->buf_num]);
                }
        }
        clear_bit(URB_BUF, &dev->flags);

        return 0;
}

static int rtl2832_sdr_alloc_stream_bufs(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;

        dev->buf_num = 0;
        dev->buf_size = BULK_BUFFER_SIZE;

        dev_dbg(&pdev->dev, "all in all I will use %u bytes for streaming\n",
                MAX_BULK_BUFS * BULK_BUFFER_SIZE);

        for (dev->buf_num = 0; dev->buf_num < MAX_BULK_BUFS; dev->buf_num++) {
                dev->buf_list[dev->buf_num] = usb_alloc_coherent(dev->udev,
                                BULK_BUFFER_SIZE, GFP_KERNEL,
                                &dev->dma_addr[dev->buf_num]);
                if (!dev->buf_list[dev->buf_num]) {
                        dev_dbg(&pdev->dev, "alloc buf=%d failed\n",
                                dev->buf_num);
                        rtl2832_sdr_free_stream_bufs(dev);
                        return -ENOMEM;
                }

                dev_dbg(&pdev->dev, "alloc buf=%d %p (dma %llu)\n",
                        dev->buf_num, dev->buf_list[dev->buf_num],
                        (long long)dev->dma_addr[dev->buf_num]);
                set_bit(URB_BUF, &dev->flags);
        }

        return 0;
}

static int rtl2832_sdr_free_urbs(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;
        int i;

        rtl2832_sdr_kill_urbs(dev);

        for (i = dev->urbs_initialized - 1; i >= 0; i--) {
                if (dev->urb_list[i]) {
                        dev_dbg(&pdev->dev, "free urb=%d\n", i);
                        /* free the URBs */
                        usb_free_urb(dev->urb_list[i]);
                }
        }
        dev->urbs_initialized = 0;

        return 0;
}

static int rtl2832_sdr_alloc_urbs(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;
        int i, j;

        /* allocate the URBs */
        for (i = 0; i < MAX_BULK_BUFS; i++) {
                dev_dbg(&pdev->dev, "alloc urb=%d\n", i);
                dev->urb_list[i] = usb_alloc_urb(0, GFP_KERNEL);
                if (!dev->urb_list[i]) {
                        for (j = 0; j < i; j++) {
                                usb_free_urb(dev->urb_list[j]);
                                dev->urb_list[j] = NULL;
                        }
                        dev->urbs_initialized = 0;
                        return -ENOMEM;
                }
                usb_fill_bulk_urb(dev->urb_list[i],
                                dev->udev,
                                usb_rcvbulkpipe(dev->udev, 0x81),
                                dev->buf_list[i],
                                BULK_BUFFER_SIZE,
                                rtl2832_sdr_urb_complete, dev);

                dev->urb_list[i]->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
                dev->urb_list[i]->transfer_dma = dev->dma_addr[i];
                dev->urbs_initialized++;
        }

        return 0;
}

/* Must be called with vb_queue_lock hold */
static void rtl2832_sdr_cleanup_queued_bufs(struct rtl2832_sdr_dev *dev,
                                            enum vb2_buffer_state state)
{
        struct platform_device *pdev = dev->pdev;
        unsigned long flags;

        dev_dbg(&pdev->dev, "\n");

        spin_lock_irqsave(&dev->queued_bufs_lock, flags);
        while (!list_empty(&dev->queued_bufs)) {
                struct rtl2832_sdr_frame_buf *buf;

                buf = list_entry(dev->queued_bufs.next,
                                struct rtl2832_sdr_frame_buf, list);
                list_del(&buf->list);
                vb2_buffer_done(&buf->vb.vb2_buf, state);
        }
        spin_unlock_irqrestore(&dev->queued_bufs_lock, flags);
}

static int rtl2832_sdr_querycap(struct file *file, void *fh,
                struct v4l2_capability *cap)
{
        struct rtl2832_sdr_dev *dev = video_drvdata(file);
        struct platform_device *pdev = dev->pdev;

        dev_dbg(&pdev->dev, "\n");

        strscpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
        strscpy(cap->card, dev->vdev.name, sizeof(cap->card));
        usb_make_path(dev->udev, cap->bus_info, sizeof(cap->bus_info));
        return 0;
}

/* Videobuf2 operations */
static int rtl2832_sdr_queue_setup(struct vb2_queue *vq,
                unsigned int *nbuffers,
                unsigned int *nplanes, unsigned int sizes[], struct device *alloc_devs[])
{
        struct rtl2832_sdr_dev *dev = vb2_get_drv_priv(vq);
        struct platform_device *pdev = dev->pdev;
        unsigned int q_num_bufs = vb2_get_num_buffers(vq);

        dev_dbg(&pdev->dev, "nbuffers=%d\n", *nbuffers);

        /* Need at least 8 buffers */
        if (q_num_bufs + *nbuffers < 8)
                *nbuffers = 8 - q_num_bufs;
        *nplanes = 1;
        sizes[0] = PAGE_ALIGN(dev->buffersize);
        dev_dbg(&pdev->dev, "nbuffers=%d sizes[0]=%d\n", *nbuffers, sizes[0]);
        return 0;
}

static int rtl2832_sdr_buf_prepare(struct vb2_buffer *vb)
{
        struct rtl2832_sdr_dev *dev = vb2_get_drv_priv(vb->vb2_queue);

        /* Don't allow queueing new buffers after device disconnection */
        if (!dev->udev)
                return -ENODEV;

        return 0;
}

static void rtl2832_sdr_buf_queue(struct vb2_buffer *vb)
{
        struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
        struct rtl2832_sdr_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
        struct rtl2832_sdr_frame_buf *buf =
                        container_of(vbuf, struct rtl2832_sdr_frame_buf, vb);
        unsigned long flags;

        /* Check the device has not disconnected between prep and queuing */
        if (!dev->udev) {
                vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
                return;
        }

        spin_lock_irqsave(&dev->queued_bufs_lock, flags);
        list_add_tail(&buf->list, &dev->queued_bufs);
        spin_unlock_irqrestore(&dev->queued_bufs_lock, flags);
}

static int rtl2832_sdr_set_adc(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;
        struct rtl2832_sdr_platform_data *pdata = pdev->dev.platform_data;
        struct dvb_frontend *fe = pdata->dvb_frontend;
        int ret;
        unsigned int f_sr, f_if;
        u8 buf[4], u8tmp1, u8tmp2;
        u64 u64tmp;
        u32 u32tmp;

        dev_dbg(&pdev->dev, "f_adc=%u\n", dev->f_adc);

        if (!test_bit(POWER_ON, &dev->flags))
                return 0;

        if (dev->f_adc == 0)
                return 0;

        f_sr = dev->f_adc;

        ret = regmap_bulk_write(dev->regmap, 0x13e, "\x00\x00", 2);
        if (ret)
                goto err;

        ret = regmap_bulk_write(dev->regmap, 0x115, "\x00\x00\x00\x00", 4);
        if (ret)
                goto err;

        /* get IF from tuner */
        if (fe->ops.tuner_ops.get_if_frequency)
                ret = fe->ops.tuner_ops.get_if_frequency(fe, &f_if);
        else
                ret = -EINVAL;

        if (ret)
                goto err;

        /* program IF */
        u64tmp = f_if % pdata->clk;
        u64tmp *= 0x400000;
        u64tmp = div_u64(u64tmp, pdata->clk);
        u64tmp = -u64tmp;
        u32tmp = u64tmp & 0x3fffff;

        dev_dbg(&pdev->dev, "f_if=%u if_ctl=%08x\n", f_if, u32tmp);

        buf[0] = (u32tmp >> 16) & 0xff;
        buf[1] = (u32tmp >>  8) & 0xff;
        buf[2] = (u32tmp >>  0) & 0xff;

        ret = regmap_bulk_write(dev->regmap, 0x119, buf, 3);
        if (ret)
                goto err;

        /* BB / IF mode */
        /* POR: 0x1b1=0x1f, 0x008=0x0d, 0x006=0x80 */
        if (f_if) {
                u8tmp1 = 0x1a; /* disable Zero-IF */
                u8tmp2 = 0x8d; /* enable ADC I */
        } else {
                u8tmp1 = 0x1b; /* enable Zero-IF, DC, IQ */
                u8tmp2 = 0xcd; /* enable ADC I, ADC Q */
        }

        ret = regmap_write(dev->regmap, 0x1b1, u8tmp1);
        if (ret)
                goto err;

        ret = regmap_write(dev->regmap, 0x008, u8tmp2);
        if (ret)
                goto err;

        ret = regmap_write(dev->regmap, 0x006, 0x80);
        if (ret)
                goto err;

        /* program sampling rate (resampling down) */
        u32tmp = div_u64(pdata->clk * 0x400000ULL, f_sr * 4U);
        u32tmp <<= 2;
        buf[0] = (u32tmp >> 24) & 0xff;
        buf[1] = (u32tmp >> 16) & 0xff;
        buf[2] = (u32tmp >>  8) & 0xff;
        buf[3] = (u32tmp >>  0) & 0xff;
        ret = regmap_bulk_write(dev->regmap, 0x19f, buf, 4);
        if (ret)
                goto err;

        /* low-pass filter */
        ret = regmap_bulk_write(dev->regmap, 0x11c,
                                "\xca\xdc\xd7\xd8\xe0\xf2\x0e\x35\x06\x50\x9c\x0d\x71\x11\x14\x71\x74\x19\x41\xa5",
                                20);
        if (ret)
                goto err;

        ret = regmap_bulk_write(dev->regmap, 0x017, "\x11\x10", 2);
        if (ret)
                goto err;

        /* mode */
        ret = regmap_write(dev->regmap, 0x019, 0x05);
        if (ret)
                goto err;

        ret = regmap_bulk_write(dev->regmap, 0x01a,
                                "\x1b\x16\x0d\x06\x01\xff", 6);
        if (ret)
                goto err;

        /* FSM */
        ret = regmap_bulk_write(dev->regmap, 0x192, "\x00\xf0\x0f", 3);
        if (ret)
                goto err;

        /* PID filter */
        ret = regmap_write(dev->regmap, 0x061, 0x60);
        if (ret)
                goto err;

        /* used RF tuner based settings */
        switch (pdata->tuner) {
        case RTL2832_SDR_TUNER_E4000:
                ret = regmap_write(dev->regmap, 0x112, 0x5a);
                ret = regmap_write(dev->regmap, 0x102, 0x40);
                ret = regmap_write(dev->regmap, 0x103, 0x5a);
                ret = regmap_write(dev->regmap, 0x1c7, 0x30);
                ret = regmap_write(dev->regmap, 0x104, 0xd0);
                ret = regmap_write(dev->regmap, 0x105, 0xbe);
                ret = regmap_write(dev->regmap, 0x1c8, 0x18);
                ret = regmap_write(dev->regmap, 0x106, 0x35);
                ret = regmap_write(dev->regmap, 0x1c9, 0x21);
                ret = regmap_write(dev->regmap, 0x1ca, 0x21);
                ret = regmap_write(dev->regmap, 0x1cb, 0x00);
                ret = regmap_write(dev->regmap, 0x107, 0x40);
                ret = regmap_write(dev->regmap, 0x1cd, 0x10);
                ret = regmap_write(dev->regmap, 0x1ce, 0x10);
                ret = regmap_write(dev->regmap, 0x108, 0x80);
                ret = regmap_write(dev->regmap, 0x109, 0x7f);
                ret = regmap_write(dev->regmap, 0x10a, 0x80);
                ret = regmap_write(dev->regmap, 0x10b, 0x7f);
                ret = regmap_write(dev->regmap, 0x00e, 0xfc);
                ret = regmap_write(dev->regmap, 0x00e, 0xfc);
                ret = regmap_write(dev->regmap, 0x011, 0xd4);
                ret = regmap_write(dev->regmap, 0x1e5, 0xf0);
                ret = regmap_write(dev->regmap, 0x1d9, 0x00);
                ret = regmap_write(dev->regmap, 0x1db, 0x00);
                ret = regmap_write(dev->regmap, 0x1dd, 0x14);
                ret = regmap_write(dev->regmap, 0x1de, 0xec);
                ret = regmap_write(dev->regmap, 0x1d8, 0x0c);
                ret = regmap_write(dev->regmap, 0x1e6, 0x02);
                ret = regmap_write(dev->regmap, 0x1d7, 0x09);
                ret = regmap_write(dev->regmap, 0x00d, 0x83);
                ret = regmap_write(dev->regmap, 0x010, 0x49);
                ret = regmap_write(dev->regmap, 0x00d, 0x87);
                ret = regmap_write(dev->regmap, 0x00d, 0x85);
                ret = regmap_write(dev->regmap, 0x013, 0x02);
                break;
        case RTL2832_SDR_TUNER_FC0012:
        case RTL2832_SDR_TUNER_FC0013:
                ret = regmap_write(dev->regmap, 0x112, 0x5a);
                ret = regmap_write(dev->regmap, 0x102, 0x40);
                ret = regmap_write(dev->regmap, 0x103, 0x5a);
                ret = regmap_write(dev->regmap, 0x1c7, 0x2c);
                ret = regmap_write(dev->regmap, 0x104, 0xcc);
                ret = regmap_write(dev->regmap, 0x105, 0xbe);
                ret = regmap_write(dev->regmap, 0x1c8, 0x16);
                ret = regmap_write(dev->regmap, 0x106, 0x35);
                ret = regmap_write(dev->regmap, 0x1c9, 0x21);
                ret = regmap_write(dev->regmap, 0x1ca, 0x21);
                ret = regmap_write(dev->regmap, 0x1cb, 0x00);
                ret = regmap_write(dev->regmap, 0x107, 0x40);
                ret = regmap_write(dev->regmap, 0x1cd, 0x10);
                ret = regmap_write(dev->regmap, 0x1ce, 0x10);
                ret = regmap_write(dev->regmap, 0x108, 0x80);
                ret = regmap_write(dev->regmap, 0x109, 0x7f);
                ret = regmap_write(dev->regmap, 0x10a, 0x80);
                ret = regmap_write(dev->regmap, 0x10b, 0x7f);
                ret = regmap_write(dev->regmap, 0x00e, 0xfc);
                ret = regmap_write(dev->regmap, 0x00e, 0xfc);
                ret = regmap_bulk_write(dev->regmap, 0x011, "\xe9\xbf", 2);
                ret = regmap_write(dev->regmap, 0x1e5, 0xf0);
                ret = regmap_write(dev->regmap, 0x1d9, 0x00);
                ret = regmap_write(dev->regmap, 0x1db, 0x00);
                ret = regmap_write(dev->regmap, 0x1dd, 0x11);
                ret = regmap_write(dev->regmap, 0x1de, 0xef);
                ret = regmap_write(dev->regmap, 0x1d8, 0x0c);
                ret = regmap_write(dev->regmap, 0x1e6, 0x02);
                ret = regmap_write(dev->regmap, 0x1d7, 0x09);
                break;
        case RTL2832_SDR_TUNER_R820T:
        case RTL2832_SDR_TUNER_R828D:
                ret = regmap_write(dev->regmap, 0x112, 0x5a);
                ret = regmap_write(dev->regmap, 0x102, 0x40);
                ret = regmap_write(dev->regmap, 0x115, 0x01);
                ret = regmap_write(dev->regmap, 0x103, 0x80);
                ret = regmap_write(dev->regmap, 0x1c7, 0x24);
                ret = regmap_write(dev->regmap, 0x104, 0xcc);
                ret = regmap_write(dev->regmap, 0x105, 0xbe);
                ret = regmap_write(dev->regmap, 0x1c8, 0x14);
                ret = regmap_write(dev->regmap, 0x106, 0x35);
                ret = regmap_write(dev->regmap, 0x1c9, 0x21);
                ret = regmap_write(dev->regmap, 0x1ca, 0x21);
                ret = regmap_write(dev->regmap, 0x1cb, 0x00);
                ret = regmap_write(dev->regmap, 0x107, 0x40);
                ret = regmap_write(dev->regmap, 0x1cd, 0x10);
                ret = regmap_write(dev->regmap, 0x1ce, 0x10);
                ret = regmap_write(dev->regmap, 0x108, 0x80);
                ret = regmap_write(dev->regmap, 0x109, 0x7f);
                ret = regmap_write(dev->regmap, 0x10a, 0x80);
                ret = regmap_write(dev->regmap, 0x10b, 0x7f);
                ret = regmap_write(dev->regmap, 0x00e, 0xfc);
                ret = regmap_write(dev->regmap, 0x00e, 0xfc);
                ret = regmap_write(dev->regmap, 0x011, 0xf4);
                break;
        case RTL2832_SDR_TUNER_FC2580:
                ret = regmap_write(dev->regmap, 0x112, 0x39);
                ret = regmap_write(dev->regmap, 0x102, 0x40);
                ret = regmap_write(dev->regmap, 0x103, 0x5a);
                ret = regmap_write(dev->regmap, 0x1c7, 0x2c);
                ret = regmap_write(dev->regmap, 0x104, 0xcc);
                ret = regmap_write(dev->regmap, 0x105, 0xbe);
                ret = regmap_write(dev->regmap, 0x1c8, 0x16);
                ret = regmap_write(dev->regmap, 0x106, 0x35);
                ret = regmap_write(dev->regmap, 0x1c9, 0x21);
                ret = regmap_write(dev->regmap, 0x1ca, 0x21);
                ret = regmap_write(dev->regmap, 0x1cb, 0x00);
                ret = regmap_write(dev->regmap, 0x107, 0x40);
                ret = regmap_write(dev->regmap, 0x1cd, 0x10);
                ret = regmap_write(dev->regmap, 0x1ce, 0x10);
                ret = regmap_write(dev->regmap, 0x108, 0x80);
                ret = regmap_write(dev->regmap, 0x109, 0x7f);
                ret = regmap_write(dev->regmap, 0x10a, 0x9c);
                ret = regmap_write(dev->regmap, 0x10b, 0x7f);
                ret = regmap_write(dev->regmap, 0x00e, 0xfc);
                ret = regmap_write(dev->regmap, 0x00e, 0xfc);
                ret = regmap_bulk_write(dev->regmap, 0x011, "\xe9\xf4", 2);
                break;
        default:
                dev_notice(&pdev->dev, "Unsupported tuner\n");
        }

        /* software reset */
        ret = regmap_update_bits(dev->regmap, 0x101, 0x04, 0x04);
        if (ret)
                goto err;

        ret = regmap_update_bits(dev->regmap, 0x101, 0x04, 0x00);
        if (ret)
                goto err;
err:
        return ret;
};

static void rtl2832_sdr_unset_adc(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;
        int ret;

        dev_dbg(&pdev->dev, "\n");

        /* PID filter */
        ret = regmap_write(dev->regmap, 0x061, 0xe0);
        if (ret)
                goto err;

        /* mode */
        ret = regmap_write(dev->regmap, 0x019, 0x20);
        if (ret)
                goto err;

        ret = regmap_bulk_write(dev->regmap, 0x017, "\x11\x10", 2);
        if (ret)
                goto err;

        /* FSM */
        ret = regmap_bulk_write(dev->regmap, 0x192, "\x00\x0f\xff", 3);
        if (ret)
                goto err;

        ret = regmap_bulk_write(dev->regmap, 0x13e, "\x40\x00", 2);
        if (ret)
                goto err;

        ret = regmap_bulk_write(dev->regmap, 0x115, "\x06\x3f\xce\xcc", 4);
        if (ret)
                goto err;
err:
        return;
};

static int rtl2832_sdr_set_tuner_freq(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;
        struct rtl2832_sdr_platform_data *pdata = pdev->dev.platform_data;
        struct dvb_frontend *fe = pdata->dvb_frontend;
        struct dtv_frontend_properties *c = &fe->dtv_property_cache;
        struct v4l2_ctrl *bandwidth_auto;
        struct v4l2_ctrl *bandwidth;

        /*
         * tuner RF (Hz)
         */
        if (dev->f_tuner == 0)
                return 0;

        /*
         * bandwidth (Hz)
         */
        bandwidth_auto = v4l2_ctrl_find(&dev->hdl,
                                        V4L2_CID_RF_TUNER_BANDWIDTH_AUTO);
        bandwidth = v4l2_ctrl_find(&dev->hdl, V4L2_CID_RF_TUNER_BANDWIDTH);
        if (v4l2_ctrl_g_ctrl(bandwidth_auto)) {
                c->bandwidth_hz = dev->f_adc;
                v4l2_ctrl_s_ctrl(bandwidth, dev->f_adc);
        } else {
                c->bandwidth_hz = v4l2_ctrl_g_ctrl(bandwidth);
        }

        c->frequency = dev->f_tuner;
        c->delivery_system = SYS_DVBT;

        dev_dbg(&pdev->dev, "frequency=%u bandwidth=%d\n",
                c->frequency, c->bandwidth_hz);

        if (!test_bit(POWER_ON, &dev->flags))
                return 0;

        if (!V4L2_SUBDEV_HAS_OP(dev->v4l2_subdev, tuner, s_frequency)) {
                if (fe->ops.tuner_ops.set_params)
                        fe->ops.tuner_ops.set_params(fe);
        }

        return 0;
};

static int rtl2832_sdr_set_tuner(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;
        struct rtl2832_sdr_platform_data *pdata = pdev->dev.platform_data;
        struct dvb_frontend *fe = pdata->dvb_frontend;

        dev_dbg(&pdev->dev, "\n");

        if (fe->ops.tuner_ops.init)
                fe->ops.tuner_ops.init(fe);

        return 0;
};

static void rtl2832_sdr_unset_tuner(struct rtl2832_sdr_dev *dev)
{
        struct platform_device *pdev = dev->pdev;
        struct rtl2832_sdr_platform_data *pdata = pdev->dev.platform_data;
        struct dvb_frontend *fe = pdata->dvb_frontend;

        dev_dbg(&pdev->dev, "\n");

        if (fe->ops.tuner_ops.sleep)
                fe->ops.tuner_ops.sleep(fe);

        return;
};

static int rtl2832_sdr_start_streaming(struct vb2_queue *vq, unsigned int count)
{
        struct rtl2832_sdr_dev *dev = vb2_get_drv_priv(vq);
        struct platform_device *pdev = dev->pdev;
        struct rtl2832_sdr_platform_data *pdata = pdev->dev.platform_data;
        struct dvb_usb_device *d = pdata->dvb_usb_device;
        int ret;

        dev_dbg(&pdev->dev, "\n");

        if (!dev->udev) {
                rtl2832_sdr_cleanup_queued_bufs(dev, VB2_BUF_STATE_QUEUED);
                return -ENODEV;
        }

        if (mutex_lock_interruptible(&dev->v4l2_lock)) {
                rtl2832_sdr_cleanup_queued_bufs(dev, VB2_BUF_STATE_QUEUED);
                return -ERESTARTSYS;
        }

        if (d->props->power_ctrl)
                d->props->power_ctrl(d, 1);

        /* enable ADC */
        if (d->props->frontend_ctrl)
                d->props->frontend_ctrl(pdata->dvb_frontend, 1);

        set_bit(POWER_ON, &dev->flags);

        /* wake-up tuner */
        if (V4L2_SUBDEV_HAS_OP(dev->v4l2_subdev, core, s_power))
                ret = v4l2_subdev_call(dev->v4l2_subdev, core, s_power, 1);
        else
                ret = rtl2832_sdr_set_tuner(dev);
        if (ret)
                goto err;

        ret = rtl2832_sdr_set_tuner_freq(dev);
        if (ret)
                goto err;

        ret = rtl2832_sdr_set_adc(dev);
        if (ret)
                goto err;

        ret = rtl2832_sdr_alloc_stream_bufs(dev);
        if (ret)
                goto err;

        ret = rtl2832_sdr_alloc_urbs(dev);
        if (ret)
                goto err;

        dev->sequence = 0;

        ret = rtl2832_sdr_submit_urbs(dev);
        if (ret)
                goto err;

        mutex_unlock(&dev->v4l2_lock);
        return 0;

err:
        rtl2832_sdr_cleanup_queued_bufs(dev, VB2_BUF_STATE_QUEUED);
        mutex_unlock(&dev->v4l2_lock);

        return ret;
}

static void rtl2832_sdr_stop_streaming(struct vb2_queue *vq)
{
        struct rtl2832_sdr_dev *dev = vb2_get_drv_priv(vq);
        struct platform_device *pdev = dev->pdev;
        struct rtl2832_sdr_platform_data *pdata = pdev->dev.platform_data;
        struct dvb_usb_device *d = pdata->dvb_usb_device;

        dev_dbg(&pdev->dev, "\n");

        mutex_lock(&dev->v4l2_lock);

        rtl2832_sdr_kill_urbs(dev);
        rtl2832_sdr_free_urbs(dev);
        rtl2832_sdr_free_stream_bufs(dev);
        rtl2832_sdr_cleanup_queued_bufs(dev, VB2_BUF_STATE_ERROR);
        rtl2832_sdr_unset_adc(dev);

        /* sleep tuner */
        if (V4L2_SUBDEV_HAS_OP(dev->v4l2_subdev, core, s_power))
                v4l2_subdev_call(dev->v4l2_subdev, core, s_power, 0);
        else
                rtl2832_sdr_unset_tuner(dev);

        clear_bit(POWER_ON, &dev->flags);

        /* disable ADC */
        if (d->props->frontend_ctrl)
                d->props->frontend_ctrl(pdata->dvb_frontend, 0);

        if (d->props->power_ctrl)
                d->props->power_ctrl(d, 0);

        mutex_unlock(&dev->v4l2_lock);
}

static const struct vb2_ops rtl2832_sdr_vb2_ops = {
        .queue_setup            = rtl2832_sdr_queue_setup,
        .buf_prepare            = rtl2832_sdr_buf_prepare,
        .buf_queue              = rtl2832_sdr_buf_queue,
        .start_streaming        = rtl2832_sdr_start_streaming,
        .stop_streaming         = rtl2832_sdr_stop_streaming,
};

static int rtl2832_sdr_g_tuner(struct file *file, void *priv,
                struct v4l2_tuner *v)
{
        struct rtl2832_sdr_dev *dev = video_drvdata(file);
        struct platform_device *pdev = dev->pdev;
        int ret;

        dev_dbg(&pdev->dev, "index=%d type=%d\n", v->index, v->type);

        if (v->index == 0) {
                strscpy(v->name, "ADC: Realtek RTL2832", sizeof(v->name));
                v->type = V4L2_TUNER_ADC;
                v->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
                v->rangelow =   300000;
                v->rangehigh = 3200000;
                ret = 0;
        } else if (v->index == 1 &&
                   V4L2_SUBDEV_HAS_OP(dev->v4l2_subdev, tuner, g_tuner)) {
                ret = v4l2_subdev_call(dev->v4l2_subdev, tuner, g_tuner, v);
        } else if (v->index == 1) {
                strscpy(v->name, "RF: <unknown>", sizeof(v->name));
                v->type = V4L2_TUNER_RF;
                v->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
                v->rangelow =    50000000;
                v->rangehigh = 2000000000;
                ret = 0;
        } else {
                ret = -EINVAL;
        }
        return ret;
}

static int rtl2832_sdr_s_tuner(struct file *file, void *priv,
                const struct v4l2_tuner *v)
{
        struct rtl2832_sdr_dev *dev = video_drvdata(file);
        struct platform_device *pdev = dev->pdev;
        int ret;

        dev_dbg(&pdev->dev, "\n");

        if (v->index == 0) {
                ret = 0;
        } else if (v->index == 1 &&
                   V4L2_SUBDEV_HAS_OP(dev->v4l2_subdev, tuner, s_tuner)) {
                ret = v4l2_subdev_call(dev->v4l2_subdev, tuner, s_tuner, v);
        } else if (v->index == 1) {
                ret = 0;
        } else {
                ret = -EINVAL;
        }
        return ret;
}

static int rtl2832_sdr_enum_freq_bands(struct file *file, void *priv,
                struct v4l2_frequency_band *band)
{
        struct rtl2832_sdr_dev *dev = video_drvdata(file);
        struct platform_device *pdev = dev->pdev;
        int ret;

        dev_dbg(&pdev->dev, "tuner=%d type=%d index=%d\n",
                band->tuner, band->type, band->index);

        if (band->tuner == 0) {
                if (band->index >= ARRAY_SIZE(bands_adc))
                        return -EINVAL;

                *band = bands_adc[band->index];
                ret = 0;
        } else if (band->tuner == 1 &&
                   V4L2_SUBDEV_HAS_OP(dev->v4l2_subdev, tuner, enum_freq_bands)) {
                ret = v4l2_subdev_call(dev->v4l2_subdev, tuner, enum_freq_bands, band);
        } else if (band->tuner == 1) {
                if (band->index >= ARRAY_SIZE(bands_fm))
                        return -EINVAL;

                *band = bands_fm[band->index];
                ret = 0;
        } else {
                ret = -EINVAL;
        }
        return ret;
}

static int rtl2832_sdr_g_frequency(struct file *file, void *priv,
                struct v4l2_frequency *f)
{
        struct rtl2832_sdr_dev *dev = video_drvdata(file);
        struct platform_device *pdev = dev->pdev;
        int ret;

        dev_dbg(&pdev->dev, "tuner=%d type=%d\n", f->tuner, f->type);

        if (f->tuner == 0) {
                f->frequency = dev->f_adc;
                f->type = V4L2_TUNER_ADC;
                ret = 0;
        } else if (f->tuner == 1 &&
                   V4L2_SUBDEV_HAS_OP(dev->v4l2_subdev, tuner, g_frequency)) {
                f->type = V4L2_TUNER_RF;
                ret = v4l2_subdev_call(dev->v4l2_subdev, tuner, g_frequency, f);
        } else if (f->tuner == 1) {
                f->frequency = dev->f_tuner;
                f->type = V4L2_TUNER_RF;
                ret = 0;
        } else {
                ret = -EINVAL;
        }
        return ret;
}

static int rtl2832_sdr_s_frequency(struct file *file, void *priv,
                const struct v4l2_frequency *f)
{
        struct rtl2832_sdr_dev *dev = video_drvdata(file);
        struct platform_device *pdev = dev->pdev;
        int ret, band;

        dev_dbg(&pdev->dev, "tuner=%d type=%d frequency=%u\n",
                f->tuner, f->type, f->frequency);

        /* ADC band midpoints */
        #define BAND_ADC_0 ((bands_adc[0].rangehigh + bands_adc[1].rangelow) / 2)
        #define BAND_ADC_1 ((bands_adc[1].rangehigh + bands_adc[2].rangelow) / 2)

        if (f->tuner == 0 && f->type == V4L2_TUNER_ADC) {
                if (f->frequency < BAND_ADC_0)
                        band = 0;
                else if (f->frequency < BAND_ADC_1)
                        band = 1;
                else
                        band = 2;

                dev->f_adc = clamp_t(unsigned int, f->frequency,
                                     bands_adc[band].rangelow,
                                     bands_adc[band].rangehigh);

                dev_dbg(&pdev->dev, "ADC frequency=%u Hz\n", dev->f_adc);
                ret = rtl2832_sdr_set_adc(dev);
        } else if (f->tuner == 1 &&
                   V4L2_SUBDEV_HAS_OP(dev->v4l2_subdev, tuner, s_frequency)) {
                ret = v4l2_subdev_call(dev->v4l2_subdev, tuner, s_frequency, f);
        } else if (f->tuner == 1) {
                dev->f_tuner = clamp_t(unsigned int, f->frequency,
                                bands_fm[0].rangelow,
                                bands_fm[0].rangehigh);
                dev_dbg(&pdev->dev, "RF frequency=%u Hz\n", f->frequency);

                ret = rtl2832_sdr_set_tuner_freq(dev);
        } else {
                ret = -EINVAL;
        }
        return ret;
}

static int rtl2832_sdr_enum_fmt_sdr_cap(struct file *file, void *priv,
                struct v4l2_fmtdesc *f)
{
        struct rtl2832_sdr_dev *dev = video_drvdata(file);
        struct platform_device *pdev = dev->pdev;

        dev_dbg(&pdev->dev, "\n");

        if (f->index >= dev->num_formats)
                return -EINVAL;

        f->pixelformat = formats[f->index].pixelformat;

        return 0;
}

static int rtl2832_sdr_g_fmt_sdr_cap(struct file *file, void *priv,
                struct v4l2_format *f)
{
        struct rtl2832_sdr_dev *dev = video_drvdata(file);
        struct platform_device *pdev = dev->pdev;

        dev_dbg(&pdev->dev, "\n");

        f->fmt.sdr.pixelformat = dev->pixelformat;
        f->fmt.sdr.buffersize = dev->buffersize;

        return 0;
}

static int rtl2832_sdr_s_fmt_sdr_cap(struct file *file, void *priv,
                struct v4l2_format *f)
{
        struct rtl2832_sdr_dev *dev = video_drvdata(file);
        struct platform_device *pdev = dev->pdev;
        struct vb2_queue *q = &dev->vb_queue;
        int i;

        dev_dbg(&pdev->dev, "pixelformat fourcc %4.4s\n",
                (char *)&f->fmt.sdr.pixelformat);

        if (vb2_is_busy(q))
                return -EBUSY;

        for (i = 0; i < dev->num_formats; i++) {
                if (formats[i].pixelformat == f->fmt.sdr.pixelformat) {
                        dev->pixelformat = formats[i].pixelformat;
                        dev->buffersize = formats[i].buffersize;
                        f->fmt.sdr.buffersize = formats[i].buffersize;
                        return 0;
                }
        }

        dev->pixelformat = formats[0].pixelformat;
        dev->buffersize = formats[0].buffersize;
        f->fmt.sdr.pixelformat = formats[0].pixelformat;
        f->fmt.sdr.buffersize = formats[0].buffersize;

        return 0;
}

static int rtl2832_sdr_try_fmt_sdr_cap(struct file *file, void *priv,
                struct v4l2_format *f)
{
        struct rtl2832_sdr_dev *dev = video_drvdata(file);
        struct platform_device *pdev = dev->pdev;
        int i;

        dev_dbg(&pdev->dev, "pixelformat fourcc %4.4s\n",
                (char *)&f->fmt.sdr.pixelformat);

        for (i = 0; i < dev->num_formats; i++) {
                if (formats[i].pixelformat == f->fmt.sdr.pixelformat) {
                        f->fmt.sdr.buffersize = formats[i].buffersize;
                        return 0;
                }
        }

        f->fmt.sdr.pixelformat = formats[0].pixelformat;
        f->fmt.sdr.buffersize = formats[0].buffersize;

        return 0;
}

static const struct v4l2_ioctl_ops rtl2832_sdr_ioctl_ops = {
        .vidioc_querycap          = rtl2832_sdr_querycap,

        .vidioc_enum_fmt_sdr_cap  = rtl2832_sdr_enum_fmt_sdr_cap,
        .vidioc_g_fmt_sdr_cap     = rtl2832_sdr_g_fmt_sdr_cap,
        .vidioc_s_fmt_sdr_cap     = rtl2832_sdr_s_fmt_sdr_cap,
        .vidioc_try_fmt_sdr_cap   = rtl2832_sdr_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           = rtl2832_sdr_g_tuner,
        .vidioc_s_tuner           = rtl2832_sdr_s_tuner,

        .vidioc_enum_freq_bands   = rtl2832_sdr_enum_freq_bands,
        .vidioc_g_frequency       = rtl2832_sdr_g_frequency,
        .vidioc_s_frequency       = rtl2832_sdr_s_frequency,

        .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 rtl2832_sdr_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 rtl2832_sdr_template = {
        .name                     = "Realtek RTL2832 SDR",
        .release                  = video_device_release_empty,
        .fops                     = &rtl2832_sdr_fops,
        .ioctl_ops                = &rtl2832_sdr_ioctl_ops,
        .device_caps              = V4L2_CAP_SDR_CAPTURE | V4L2_CAP_STREAMING |
                                    V4L2_CAP_READWRITE | V4L2_CAP_TUNER,
};

static int rtl2832_sdr_s_ctrl(struct v4l2_ctrl *ctrl)
{
        struct rtl2832_sdr_dev *dev =
                        container_of(ctrl->handler, struct rtl2832_sdr_dev,
                                        hdl);
        struct platform_device *pdev = dev->pdev;
        struct rtl2832_sdr_platform_data *pdata = pdev->dev.platform_data;
        struct dvb_frontend *fe = pdata->dvb_frontend;
        struct dtv_frontend_properties *c = &fe->dtv_property_cache;
        int ret;

        dev_dbg(&pdev->dev, "id=%d name=%s val=%d min=%lld max=%lld step=%lld\n",
                ctrl->id, ctrl->name, ctrl->val, ctrl->minimum, ctrl->maximum,
                ctrl->step);

        switch (ctrl->id) {
        case V4L2_CID_RF_TUNER_BANDWIDTH_AUTO:
        case V4L2_CID_RF_TUNER_BANDWIDTH:
                /* TODO: these controls should be moved to tuner drivers */
                if (dev->bandwidth_auto->val) {
                        /* Round towards the closest legal value */
                        s32 val = dev->f_adc + div_u64(dev->bandwidth->step, 2);
                        u32 offset;

                        val = clamp_t(s32, val, dev->bandwidth->minimum,
                                      dev->bandwidth->maximum);
                        offset = val - dev->bandwidth->minimum;
                        offset = dev->bandwidth->step *
                                div_u64(offset, dev->bandwidth->step);
                        dev->bandwidth->val = dev->bandwidth->minimum + offset;
                }
                c->bandwidth_hz = dev->bandwidth->val;

                if (!test_bit(POWER_ON, &dev->flags))
                        return 0;

                if (fe->ops.tuner_ops.set_params)
                        ret = fe->ops.tuner_ops.set_params(fe);
                else
                        ret = 0;
                break;
        default:
                ret = -EINVAL;
        }

        return ret;
}

static const struct v4l2_ctrl_ops rtl2832_sdr_ctrl_ops = {
        .s_ctrl = rtl2832_sdr_s_ctrl,
};

static void rtl2832_sdr_video_release(struct v4l2_device *v)
{
        struct rtl2832_sdr_dev *dev =
                        container_of(v, struct rtl2832_sdr_dev, v4l2_dev);
        struct platform_device *pdev = dev->pdev;

        dev_dbg(&pdev->dev, "\n");

        v4l2_ctrl_handler_free(&dev->hdl);
        v4l2_device_unregister(&dev->v4l2_dev);
        kfree(dev);
}

/* Platform driver interface */
static int rtl2832_sdr_probe(struct platform_device *pdev)
{
        struct rtl2832_sdr_dev *dev;
        struct rtl2832_sdr_platform_data *pdata = pdev->dev.platform_data;
        const struct v4l2_ctrl_ops *ops = &rtl2832_sdr_ctrl_ops;
        struct v4l2_subdev *subdev;
        int ret;

        dev_dbg(&pdev->dev, "\n");

        if (!pdata) {
                dev_err(&pdev->dev, "Cannot proceed without platform data\n");
                ret = -EINVAL;
                goto err;
        }
        if (!pdev->dev.parent->driver) {
                dev_dbg(&pdev->dev, "No parent device\n");
                ret = -EINVAL;
                goto err;
        }
        /* try to refcount host drv since we are the consumer */
        if (!try_module_get(pdev->dev.parent->driver->owner)) {
                dev_err(&pdev->dev, "Refcount fail");
                ret = -EINVAL;
                goto err;
        }
        dev = kzalloc_obj(*dev);
        if (dev == NULL) {
                ret = -ENOMEM;
                goto err_module_put;
        }

        /* setup the state */
        subdev = pdata->v4l2_subdev;
        dev->v4l2_subdev = pdata->v4l2_subdev;
        dev->pdev = pdev;
        dev->regmap = pdata->regmap;
        dev->udev = pdata->dvb_usb_device->udev;
        dev->f_adc = bands_adc[0].rangelow;
        dev->f_tuner = bands_fm[0].rangelow;
        dev->pixelformat = formats[0].pixelformat;
        dev->buffersize = formats[0].buffersize;
        dev->num_formats = NUM_FORMATS;
        if (!rtl2832_sdr_emulated_fmt)
                dev->num_formats -= 1;

        mutex_init(&dev->v4l2_lock);
        mutex_init(&dev->vb_queue_lock);
        spin_lock_init(&dev->queued_bufs_lock);
        INIT_LIST_HEAD(&dev->queued_bufs);

        /* Init videobuf2 queue structure */
        dev->vb_queue.type = V4L2_BUF_TYPE_SDR_CAPTURE;
        dev->vb_queue.io_modes = VB2_MMAP | VB2_USERPTR | VB2_READ;
        dev->vb_queue.drv_priv = dev;
        dev->vb_queue.buf_struct_size = sizeof(struct rtl2832_sdr_frame_buf);
        dev->vb_queue.ops = &rtl2832_sdr_vb2_ops;
        dev->vb_queue.mem_ops = &vb2_vmalloc_memops;
        dev->vb_queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
        dev->vb_queue.lock = &dev->vb_queue_lock;
        ret = vb2_queue_init(&dev->vb_queue);
        if (ret) {
                dev_err(&pdev->dev, "Could not initialize vb2 queue\n");
                goto err_kfree;
        }

        /* Register controls */
        switch (pdata->tuner) {
        case RTL2832_SDR_TUNER_E4000:
                v4l2_ctrl_handler_init(&dev->hdl, 9);
                if (subdev)
                        v4l2_ctrl_add_handler(&dev->hdl, subdev->ctrl_handler,
                                              NULL, true);
                break;
        case RTL2832_SDR_TUNER_R820T:
        case RTL2832_SDR_TUNER_R828D:
                v4l2_ctrl_handler_init(&dev->hdl, 2);
                dev->bandwidth_auto = v4l2_ctrl_new_std(&dev->hdl, ops,
                                                        V4L2_CID_RF_TUNER_BANDWIDTH_AUTO,
                                                        0, 1, 1, 1);
                dev->bandwidth = v4l2_ctrl_new_std(&dev->hdl, ops,
                                                   V4L2_CID_RF_TUNER_BANDWIDTH,
                                                   0, 8000000, 100000, 0);
                v4l2_ctrl_auto_cluster(2, &dev->bandwidth_auto, 0, false);
                break;
        case RTL2832_SDR_TUNER_FC0012:
        case RTL2832_SDR_TUNER_FC0013:
                v4l2_ctrl_handler_init(&dev->hdl, 2);
                dev->bandwidth_auto = v4l2_ctrl_new_std(&dev->hdl, ops,
                                                        V4L2_CID_RF_TUNER_BANDWIDTH_AUTO,
                                                        0, 1, 1, 1);
                dev->bandwidth = v4l2_ctrl_new_std(&dev->hdl, ops,
                                                   V4L2_CID_RF_TUNER_BANDWIDTH,
                                                   6000000, 8000000, 1000000,
                                                   6000000);
                v4l2_ctrl_auto_cluster(2, &dev->bandwidth_auto, 0, false);
                break;
        case RTL2832_SDR_TUNER_FC2580:
                v4l2_ctrl_handler_init(&dev->hdl, 2);
                if (subdev)
                        v4l2_ctrl_add_handler(&dev->hdl, subdev->ctrl_handler,
                                              NULL, true);
                break;
        default:
                v4l2_ctrl_handler_init(&dev->hdl, 0);
                dev_err(&pdev->dev, "Unsupported tuner\n");
                ret = -ENODEV;
                goto err_v4l2_ctrl_handler_free;
        }
        if (dev->hdl.error) {
                ret = dev->hdl.error;
                dev_err(&pdev->dev, "Could not initialize controls\n");
                goto err_v4l2_ctrl_handler_free;
        }

        /* Init video_device structure */
        dev->vdev = rtl2832_sdr_template;
        dev->vdev.queue = &dev->vb_queue;
        video_set_drvdata(&dev->vdev, dev);

        /* Register the v4l2_device structure */
        dev->v4l2_dev.release = rtl2832_sdr_video_release;
        ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
        if (ret) {
                dev_err(&pdev->dev, "Failed to register v4l2-device %d\n", ret);
                goto err_v4l2_ctrl_handler_free;
        }

        dev->v4l2_dev.ctrl_handler = &dev->hdl;
        dev->vdev.v4l2_dev = &dev->v4l2_dev;
        dev->vdev.lock = &dev->v4l2_lock;
        dev->vdev.vfl_dir = VFL_DIR_RX;

        ret = video_register_device(&dev->vdev, VFL_TYPE_SDR, -1);
        if (ret) {
                dev_err(&pdev->dev, "Failed to register as video device %d\n",
                        ret);
                goto err_v4l2_device_unregister;
        }
        dev_info(&pdev->dev, "Registered as %s\n",
                 video_device_node_name(&dev->vdev));
        dev_info(&pdev->dev, "Realtek RTL2832 SDR attached\n");
        dev_notice(&pdev->dev,
                   "SDR API is still slightly experimental and functionality changes may follow\n");
        platform_set_drvdata(pdev, dev);
        return 0;
err_v4l2_device_unregister:
        v4l2_device_unregister(&dev->v4l2_dev);
err_v4l2_ctrl_handler_free:
        v4l2_ctrl_handler_free(&dev->hdl);
err_kfree:
        kfree(dev);
err_module_put:
        module_put(pdev->dev.parent->driver->owner);
err:
        return ret;
}

static void rtl2832_sdr_remove(struct platform_device *pdev)
{
        struct rtl2832_sdr_dev *dev = platform_get_drvdata(pdev);

        dev_dbg(&pdev->dev, "\n");

        mutex_lock(&dev->vb_queue_lock);
        mutex_lock(&dev->v4l2_lock);
        /* No need to keep the urbs around after disconnection */
        dev->udev = NULL;
        v4l2_device_disconnect(&dev->v4l2_dev);
        video_unregister_device(&dev->vdev);
        mutex_unlock(&dev->v4l2_lock);
        mutex_unlock(&dev->vb_queue_lock);
        v4l2_device_put(&dev->v4l2_dev);
        module_put(pdev->dev.parent->driver->owner);
}

static struct platform_driver rtl2832_sdr_driver = {
        .driver = {
                .name   = "rtl2832_sdr",
        },
        .probe          = rtl2832_sdr_probe,
        .remove         = rtl2832_sdr_remove,
};
module_platform_driver(rtl2832_sdr_driver);

MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
MODULE_DESCRIPTION("Realtek RTL2832 SDR driver");
MODULE_LICENSE("GPL");