Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

3 files changed, 1562 insertions, 0 deletions

diff --git a/drivers/media/usb/hackrf/Kconfig b/drivers/media/usb/hackrf/Kconfig
new file mode 100644
index 000000000..1cf9b4d3a
--- /dev/null
+++ b/drivers/media/usb/hackrf/Kconfig
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config USB_HACKRF
+	tristate "HackRF"
+	depends on VIDEO_DEV
+	select VIDEOBUF2_VMALLOC
+	help
+	  This is a video4linux2 driver for HackRF SDR device.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called hackrf
+
diff --git a/drivers/media/usb/hackrf/Makefile b/drivers/media/usb/hackrf/Makefile
new file mode 100644
index 000000000..0ac96d0b8
--- /dev/null
+++ b/drivers/media/usb/hackrf/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_USB_HACKRF)              += hackrf.o
diff --git a/drivers/media/usb/hackrf/hackrf.c b/drivers/media/usb/hackrf/hackrf.c
new file mode 100644
index 000000000..a15829a60
--- /dev/null
+++ b/drivers/media/usb/hackrf/hackrf.c
@@ -0,0 +1,1549 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * HackRF driver
+ *
+ * Copyright (C) 2014 Antti Palosaari <crope@iki.fi>
+ */
+
+#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-v4l2.h>
+#include <media/videobuf2-vmalloc.h>
+
+/*
+ * Used Avago MGA-81563 RF amplifier could be destroyed pretty easily with too
+ * strong signal or transmitting to bad antenna.
+ * Set RF gain control to 'grabbed' state by default for sure.
+ */
+static bool hackrf_enable_rf_gain_ctrl;
+module_param_named(enable_rf_gain_ctrl, hackrf_enable_rf_gain_ctrl, bool, 0644);
+MODULE_PARM_DESC(enable_rf_gain_ctrl, "enable RX/TX RF amplifier control (warn: could damage amplifier)");
+
+/* HackRF USB API commands (from HackRF Library) */
+enum {
+	CMD_SET_TRANSCEIVER_MODE           = 0x01,
+	CMD_SAMPLE_RATE_SET                = 0x06,
+	CMD_BASEBAND_FILTER_BANDWIDTH_SET  = 0x07,
+	CMD_BOARD_ID_READ                  = 0x0e,
+	CMD_VERSION_STRING_READ            = 0x0f,
+	CMD_SET_FREQ                       = 0x10,
+	CMD_AMP_ENABLE                     = 0x11,
+	CMD_SET_LNA_GAIN                   = 0x13,
+	CMD_SET_VGA_GAIN                   = 0x14,
+	CMD_SET_TXVGA_GAIN                 = 0x15,
+};
+
+/*
+ *       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_adc_dac[] = {
+	{
+		.tuner = 0,
+		.type = V4L2_TUNER_SDR,
+		.index = 0,
+		.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
+		.rangelow   =   200000,
+		.rangehigh  = 24000000,
+	},
+};
+
+static const struct v4l2_frequency_band bands_rx_tx[] = {
+	{
+		.tuner = 1,
+		.type = V4L2_TUNER_RF,
+		.index = 0,
+		.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
+		.rangelow   =          1,
+		.rangehigh  = 4294967294LL, /* max u32, hw goes over 7GHz */
+	},
+};
+
+/* stream formats */
+struct hackrf_format {
+	u32	pixelformat;
+	u32	buffersize;
+};
+
+/* format descriptions for capture and preview */
+static struct hackrf_format formats[] = {
+	{
+		.pixelformat	= V4L2_SDR_FMT_CS8,
+		.buffersize	= BULK_BUFFER_SIZE,
+	},
+};
+
+static const unsigned int NUM_FORMATS = ARRAY_SIZE(formats);
+
+/* intermediate buffers with raw data from the USB device */
+struct hackrf_buffer {
+	struct vb2_v4l2_buffer vb;
+	struct list_head list;
+};
+
+struct hackrf_dev {
+#define USB_STATE_URB_BUF                1 /* XXX: set manually */
+#define RX_ON                            4
+#define TX_ON                            5
+#define RX_ADC_FREQUENCY                11
+#define TX_DAC_FREQUENCY                12
+#define RX_BANDWIDTH                    13
+#define TX_BANDWIDTH                    14
+#define RX_RF_FREQUENCY                 15
+#define TX_RF_FREQUENCY                 16
+#define RX_RF_GAIN                      17
+#define TX_RF_GAIN                      18
+#define RX_IF_GAIN                      19
+#define RX_LNA_GAIN                     20
+#define TX_LNA_GAIN                     21
+	unsigned long flags;
+
+	struct usb_interface *intf;
+	struct device *dev;
+	struct usb_device *udev;
+	struct video_device rx_vdev;
+	struct video_device tx_vdev;
+	struct v4l2_device v4l2_dev;
+
+	/* videobuf2 queue and queued buffers list */
+	struct vb2_queue rx_vb2_queue;
+	struct vb2_queue tx_vb2_queue;
+	struct list_head rx_buffer_list;
+	struct list_head tx_buffer_list;
+	spinlock_t buffer_list_lock; /* Protects buffer_list */
+	unsigned int sequence;	     /* Buffer sequence counter */
+	unsigned int vb_full;        /* vb is full and packets dropped */
+	unsigned int vb_empty;       /* vb is empty 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 */
+
+	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_dac;
+	unsigned int f_rx;
+	unsigned int f_tx;
+	u32 pixelformat;
+	u32 buffersize;
+
+	/* Controls */
+	struct v4l2_ctrl_handler rx_ctrl_handler;
+	struct v4l2_ctrl *rx_bandwidth_auto;
+	struct v4l2_ctrl *rx_bandwidth;
+	struct v4l2_ctrl *rx_rf_gain;
+	struct v4l2_ctrl *rx_lna_gain;
+	struct v4l2_ctrl *rx_if_gain;
+	struct v4l2_ctrl_handler tx_ctrl_handler;
+	struct v4l2_ctrl *tx_bandwidth_auto;
+	struct v4l2_ctrl *tx_bandwidth;
+	struct v4l2_ctrl *tx_rf_gain;
+	struct v4l2_ctrl *tx_lna_gain;
+
+	/* Sample rate calc */
+	unsigned long jiffies_next;
+	unsigned int sample;
+	unsigned int sample_measured;
+};
+
+#define hackrf_dbg_usb_control_msg(_dev, _r, _t, _v, _i, _b, _l) { \
+	char *_direction; \
+	if (_t & USB_DIR_IN) \
+		_direction = "<<<"; \
+	else \
+		_direction = ">>>"; \
+	dev_dbg(_dev, "%02x %02x %02x %02x %02x %02x %02x %02x %s %*ph\n", \
+			_t, _r, _v & 0xff, _v >> 8, _i & 0xff, \
+			_i >> 8, _l & 0xff, _l >> 8, _direction, _l, _b); \
+}
+
+/* execute firmware command */
+static int hackrf_ctrl_msg(struct hackrf_dev *dev, u8 request, u16 value,
+		u16 index, u8 *data, u16 size)
+{
+	int ret;
+	unsigned int pipe;
+	u8 requesttype;
+
+	switch (request) {
+	case CMD_SET_TRANSCEIVER_MODE:
+	case CMD_SET_FREQ:
+	case CMD_AMP_ENABLE:
+	case CMD_SAMPLE_RATE_SET:
+	case CMD_BASEBAND_FILTER_BANDWIDTH_SET:
+		pipe = usb_sndctrlpipe(dev->udev, 0);
+		requesttype = (USB_TYPE_VENDOR | USB_DIR_OUT);
+		break;
+	case CMD_BOARD_ID_READ:
+	case CMD_VERSION_STRING_READ:
+	case CMD_SET_LNA_GAIN:
+	case CMD_SET_VGA_GAIN:
+	case CMD_SET_TXVGA_GAIN:
+		pipe = usb_rcvctrlpipe(dev->udev, 0);
+		requesttype = (USB_TYPE_VENDOR | USB_DIR_IN);
+		break;
+	default:
+		dev_err(dev->dev, "Unknown command %02x\n", request);
+		ret = -EINVAL;
+		goto err;
+	}
+
+	/* write request */
+	if (!(requesttype & USB_DIR_IN))
+		memcpy(dev->buf, data, size);
+
+	ret = usb_control_msg(dev->udev, pipe, request, requesttype, value,
+			index, dev->buf, size, 1000);
+	hackrf_dbg_usb_control_msg(dev->dev, request, requesttype, value,
+			index, dev->buf, size);
+	if (ret < 0) {
+		dev_err(dev->dev, "usb_control_msg() failed %d request %02x\n",
+				ret, request);
+		goto err;
+	}
+
+	/* read request */
+	if (requesttype & USB_DIR_IN)
+		memcpy(data, dev->buf, size);
+
+	return 0;
+err:
+	return ret;
+}
+
+static int hackrf_set_params(struct hackrf_dev *dev)
+{
+	struct usb_interface *intf = dev->intf;
+	int ret, i;
+	u8 buf[8], u8tmp;
+	unsigned int uitmp, uitmp1, uitmp2;
+	const bool rx = test_bit(RX_ON, &dev->flags);
+	const bool tx = test_bit(TX_ON, &dev->flags);
+	static const struct {
+		u32 freq;
+	} bandwidth_lut[] = {
+		{ 1750000}, /*  1.75 MHz */
+		{ 2500000}, /*  2.5  MHz */
+		{ 3500000}, /*  3.5  MHz */
+		{ 5000000}, /*  5    MHz */
+		{ 5500000}, /*  5.5  MHz */
+		{ 6000000}, /*  6    MHz */
+		{ 7000000}, /*  7    MHz */
+		{ 8000000}, /*  8    MHz */
+		{ 9000000}, /*  9    MHz */
+		{10000000}, /* 10    MHz */
+		{12000000}, /* 12    MHz */
+		{14000000}, /* 14    MHz */
+		{15000000}, /* 15    MHz */
+		{20000000}, /* 20    MHz */
+		{24000000}, /* 24    MHz */
+		{28000000}, /* 28    MHz */
+	};
+
+	if (!rx && !tx) {
+		dev_dbg(&intf->dev, "device is sleeping\n");
+		return 0;
+	}
+
+	/* ADC / DAC frequency */
+	if (rx && test_and_clear_bit(RX_ADC_FREQUENCY, &dev->flags)) {
+		dev_dbg(&intf->dev, "RX ADC frequency=%u Hz\n", dev->f_adc);
+		uitmp1 = dev->f_adc;
+		uitmp2 = 1;
+		set_bit(TX_DAC_FREQUENCY, &dev->flags);
+	} else if (tx && test_and_clear_bit(TX_DAC_FREQUENCY, &dev->flags)) {
+		dev_dbg(&intf->dev, "TX DAC frequency=%u Hz\n", dev->f_dac);
+		uitmp1 = dev->f_dac;
+		uitmp2 = 1;
+		set_bit(RX_ADC_FREQUENCY, &dev->flags);
+	} else {
+		uitmp1 = uitmp2 = 0;
+	}
+	if (uitmp1 || uitmp2) {
+		buf[0] = (uitmp1 >>  0) & 0xff;
+		buf[1] = (uitmp1 >>  8) & 0xff;
+		buf[2] = (uitmp1 >> 16) & 0xff;
+		buf[3] = (uitmp1 >> 24) & 0xff;
+		buf[4] = (uitmp2 >>  0) & 0xff;
+		buf[5] = (uitmp2 >>  8) & 0xff;
+		buf[6] = (uitmp2 >> 16) & 0xff;
+		buf[7] = (uitmp2 >> 24) & 0xff;
+		ret = hackrf_ctrl_msg(dev, CMD_SAMPLE_RATE_SET, 0, 0, buf, 8);
+		if (ret)
+			goto err;
+	}
+
+	/* bandwidth */
+	if (rx && test_and_clear_bit(RX_BANDWIDTH, &dev->flags)) {
+		if (dev->rx_bandwidth_auto->val == true)
+			uitmp = dev->f_adc;
+		else
+			uitmp = dev->rx_bandwidth->val;
+
+		for (i = 0; i < ARRAY_SIZE(bandwidth_lut); i++) {
+			if (uitmp <= bandwidth_lut[i].freq) {
+				uitmp = bandwidth_lut[i].freq;
+				break;
+			}
+		}
+		dev->rx_bandwidth->val = uitmp;
+		dev->rx_bandwidth->cur.val = uitmp;
+		dev_dbg(&intf->dev, "RX bandwidth selected=%u\n", uitmp);
+		set_bit(TX_BANDWIDTH, &dev->flags);
+	} else if (tx && test_and_clear_bit(TX_BANDWIDTH, &dev->flags)) {
+		if (dev->tx_bandwidth_auto->val == true)
+			uitmp = dev->f_dac;
+		else
+			uitmp = dev->tx_bandwidth->val;
+
+		for (i = 0; i < ARRAY_SIZE(bandwidth_lut); i++) {
+			if (uitmp <= bandwidth_lut[i].freq) {
+				uitmp = bandwidth_lut[i].freq;
+				break;
+			}
+		}
+		dev->tx_bandwidth->val = uitmp;
+		dev->tx_bandwidth->cur.val = uitmp;
+		dev_dbg(&intf->dev, "TX bandwidth selected=%u\n", uitmp);
+		set_bit(RX_BANDWIDTH, &dev->flags);
+	} else {
+		uitmp = 0;
+	}
+	if (uitmp) {
+		uitmp1 = uitmp2 = 0;
+		uitmp1 |= ((uitmp >>  0) & 0xff) << 0;
+		uitmp1 |= ((uitmp >>  8) & 0xff) << 8;
+		uitmp2 |= ((uitmp >> 16) & 0xff) << 0;
+		uitmp2 |= ((uitmp >> 24) & 0xff) << 8;
+		ret = hackrf_ctrl_msg(dev, CMD_BASEBAND_FILTER_BANDWIDTH_SET,
+				      uitmp1, uitmp2, NULL, 0);
+		if (ret)
+			goto err;
+	}
+
+	/* RX / TX RF frequency */
+	if (rx && test_and_clear_bit(RX_RF_FREQUENCY, &dev->flags)) {
+		dev_dbg(&intf->dev, "RX RF frequency=%u Hz\n", dev->f_rx);
+		uitmp1 = dev->f_rx / 1000000;
+		uitmp2 = dev->f_rx % 1000000;
+		set_bit(TX_RF_FREQUENCY, &dev->flags);
+	} else if (tx && test_and_clear_bit(TX_RF_FREQUENCY, &dev->flags)) {
+		dev_dbg(&intf->dev, "TX RF frequency=%u Hz\n", dev->f_tx);
+		uitmp1 = dev->f_tx / 1000000;
+		uitmp2 = dev->f_tx % 1000000;
+		set_bit(RX_RF_FREQUENCY, &dev->flags);
+	} else {
+		uitmp1 = uitmp2 = 0;
+	}
+	if (uitmp1 || uitmp2) {
+		buf[0] = (uitmp1 >>  0) & 0xff;
+		buf[1] = (uitmp1 >>  8) & 0xff;
+		buf[2] = (uitmp1 >> 16) & 0xff;
+		buf[3] = (uitmp1 >> 24) & 0xff;
+		buf[4] = (uitmp2 >>  0) & 0xff;
+		buf[5] = (uitmp2 >>  8) & 0xff;
+		buf[6] = (uitmp2 >> 16) & 0xff;
+		buf[7] = (uitmp2 >> 24) & 0xff;
+		ret = hackrf_ctrl_msg(dev, CMD_SET_FREQ, 0, 0, buf, 8);
+		if (ret)
+			goto err;
+	}
+
+	/* RX RF gain */
+	if (rx && test_and_clear_bit(RX_RF_GAIN, &dev->flags)) {
+		dev_dbg(&intf->dev, "RX RF gain val=%d->%d\n",
+			dev->rx_rf_gain->cur.val, dev->rx_rf_gain->val);
+
+		u8tmp = (dev->rx_rf_gain->val) ? 1 : 0;
+		ret = hackrf_ctrl_msg(dev, CMD_AMP_ENABLE, u8tmp, 0, NULL, 0);
+		if (ret)
+			goto err;
+		set_bit(TX_RF_GAIN, &dev->flags);
+	}
+
+	/* TX RF gain */
+	if (tx && test_and_clear_bit(TX_RF_GAIN, &dev->flags)) {
+		dev_dbg(&intf->dev, "TX RF gain val=%d->%d\n",
+			dev->tx_rf_gain->cur.val, dev->tx_rf_gain->val);
+
+		u8tmp = (dev->tx_rf_gain->val) ? 1 : 0;
+		ret = hackrf_ctrl_msg(dev, CMD_AMP_ENABLE, u8tmp, 0, NULL, 0);
+		if (ret)
+			goto err;
+		set_bit(RX_RF_GAIN, &dev->flags);
+	}
+
+	/* RX LNA gain */
+	if (rx && test_and_clear_bit(RX_LNA_GAIN, &dev->flags)) {
+		dev_dbg(dev->dev, "RX LNA gain val=%d->%d\n",
+			dev->rx_lna_gain->cur.val, dev->rx_lna_gain->val);
+
+		ret = hackrf_ctrl_msg(dev, CMD_SET_LNA_GAIN, 0,
+				      dev->rx_lna_gain->val, &u8tmp, 1);
+		if (ret)
+			goto err;
+	}
+
+	/* RX IF gain */
+	if (rx && test_and_clear_bit(RX_IF_GAIN, &dev->flags)) {
+		dev_dbg(&intf->dev, "IF gain val=%d->%d\n",
+			dev->rx_if_gain->cur.val, dev->rx_if_gain->val);
+
+		ret = hackrf_ctrl_msg(dev, CMD_SET_VGA_GAIN, 0,
+				      dev->rx_if_gain->val, &u8tmp, 1);
+		if (ret)
+			goto err;
+	}
+
+	/* TX LNA gain */
+	if (tx && test_and_clear_bit(TX_LNA_GAIN, &dev->flags)) {
+		dev_dbg(&intf->dev, "TX LNA gain val=%d->%d\n",
+			dev->tx_lna_gain->cur.val, dev->tx_lna_gain->val);
+
+		ret = hackrf_ctrl_msg(dev, CMD_SET_TXVGA_GAIN, 0,
+				      dev->tx_lna_gain->val, &u8tmp, 1);
+		if (ret)
+			goto err;
+	}
+
+	return 0;
+err:
+	dev_dbg(&intf->dev, "failed=%d\n", ret);
+	return ret;
+}
+
+/* Private functions */
+static struct hackrf_buffer *hackrf_get_next_buffer(struct hackrf_dev *dev,
+						    struct list_head *buffer_list)
+{
+	unsigned long flags;
+	struct hackrf_buffer *buffer = NULL;
+
+	spin_lock_irqsave(&dev->buffer_list_lock, flags);
+	if (list_empty(buffer_list))
+		goto leave;
+
+	buffer = list_entry(buffer_list->next, struct hackrf_buffer, list);
+	list_del(&buffer->list);
+leave:
+	spin_unlock_irqrestore(&dev->buffer_list_lock, flags);
+	return buffer;
+}
+
+static void hackrf_copy_stream(struct hackrf_dev *dev, void *dst, void *src,
+			       unsigned int src_len)
+{
+	memcpy(dst, src, src_len);
+
+	/* 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(dev->dev, "slen=%u samples=%u msecs=%u sample rate=%lu\n",
+				src_len, samples, msecs,
+				samples * 1000UL / msecs);
+	}
+
+	/* total number of samples */
+	dev->sample += src_len / 2;
+}
+
+/*
+ * 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 hackrf_urb_complete_in(struct urb *urb)
+{
+	struct hackrf_dev *dev = urb->context;
+	struct usb_interface *intf = dev->intf;
+	struct hackrf_buffer *buffer;
+	unsigned int len;
+
+	dev_dbg_ratelimited(&intf->dev, "status=%d length=%u/%u\n", urb->status,
+			    urb->actual_length, urb->transfer_buffer_length);
+
+	switch (urb->status) {
+	case 0:             /* success */
+	case -ETIMEDOUT:    /* NAK */
+		break;
+	case -ECONNRESET:   /* kill */
+	case -ENOENT:
+	case -ESHUTDOWN:
+		return;
+	default:            /* error */
+		dev_err_ratelimited(&intf->dev, "URB failed %d\n", urb->status);
+		goto exit_usb_submit_urb;
+	}
+
+	/* get buffer to write */
+	buffer = hackrf_get_next_buffer(dev, &dev->rx_buffer_list);
+	if (unlikely(buffer == NULL)) {
+		dev->vb_full++;
+		dev_notice_ratelimited(&intf->dev,
+				       "buffer is full - %u packets dropped\n",
+				       dev->vb_full);
+		goto exit_usb_submit_urb;
+	}
+
+	len = min_t(unsigned long, vb2_plane_size(&buffer->vb.vb2_buf, 0),
+		    urb->actual_length);
+	hackrf_copy_stream(dev, vb2_plane_vaddr(&buffer->vb.vb2_buf, 0),
+		    urb->transfer_buffer, len);
+	vb2_set_plane_payload(&buffer->vb.vb2_buf, 0, len);
+	buffer->vb.sequence = dev->sequence++;
+	buffer->vb.vb2_buf.timestamp = ktime_get_ns();
+	vb2_buffer_done(&buffer->vb.vb2_buf, VB2_BUF_STATE_DONE);
+exit_usb_submit_urb:
+	usb_submit_urb(urb, GFP_ATOMIC);
+}
+
+static void hackrf_urb_complete_out(struct urb *urb)
+{
+	struct hackrf_dev *dev = urb->context;
+	struct usb_interface *intf = dev->intf;
+	struct hackrf_buffer *buffer;
+	unsigned int len;
+
+	dev_dbg_ratelimited(&intf->dev, "status=%d length=%u/%u\n", urb->status,
+			    urb->actual_length, urb->transfer_buffer_length);
+
+	switch (urb->status) {
+	case 0:             /* success */
+	case -ETIMEDOUT:    /* NAK */
+		break;
+	case -ECONNRESET:   /* kill */
+	case -ENOENT:
+	case -ESHUTDOWN:
+		return;
+	default:            /* error */
+		dev_err_ratelimited(&intf->dev, "URB failed %d\n", urb->status);
+	}
+
+	/* get buffer to read */
+	buffer = hackrf_get_next_buffer(dev, &dev->tx_buffer_list);
+	if (unlikely(buffer == NULL)) {
+		dev->vb_empty++;
+		dev_notice_ratelimited(&intf->dev,
+				       "buffer is empty - %u packets dropped\n",
+				       dev->vb_empty);
+		urb->actual_length = 0;
+		goto exit_usb_submit_urb;
+	}
+
+	len = min_t(unsigned long, urb->transfer_buffer_length,
+		    vb2_get_plane_payload(&buffer->vb.vb2_buf, 0));
+	hackrf_copy_stream(dev, urb->transfer_buffer,
+			   vb2_plane_vaddr(&buffer->vb.vb2_buf, 0), len);
+	urb->actual_length = len;
+	buffer->vb.sequence = dev->sequence++;
+	buffer->vb.vb2_buf.timestamp = ktime_get_ns();
+	vb2_buffer_done(&buffer->vb.vb2_buf, VB2_BUF_STATE_DONE);
+exit_usb_submit_urb:
+	usb_submit_urb(urb, GFP_ATOMIC);
+}
+
+static int hackrf_kill_urbs(struct hackrf_dev *dev)
+{
+	int i;
+
+	for (i = dev->urbs_submitted - 1; i >= 0; i--) {
+		dev_dbg(dev->dev, "kill urb=%d\n", i);
+		/* stop the URB */
+		usb_kill_urb(dev->urb_list[i]);
+	}
+	dev->urbs_submitted = 0;
+
+	return 0;
+}
+
+static int hackrf_submit_urbs(struct hackrf_dev *dev)
+{
+	int i, ret;
+
+	for (i = 0; i < dev->urbs_initialized; i++) {
+		dev_dbg(dev->dev, "submit urb=%d\n", i);
+		ret = usb_submit_urb(dev->urb_list[i], GFP_KERNEL);
+		if (ret) {
+			dev_err(dev->dev, "Could not submit URB no. %d - get them all back\n",
+					i);
+			hackrf_kill_urbs(dev);
+			return ret;
+		}
+		dev->urbs_submitted++;
+	}
+
+	return 0;
+}
+
+static int hackrf_free_stream_bufs(struct hackrf_dev *dev)
+{
+	if (dev->flags & USB_STATE_URB_BUF) {
+		while (dev->buf_num) {
+			dev->buf_num--;
+			dev_dbg(dev->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]);
+		}
+	}
+	dev->flags &= ~USB_STATE_URB_BUF;
+
+	return 0;
+}
+
+static int hackrf_alloc_stream_bufs(struct hackrf_dev *dev)
+{
+	dev->buf_num = 0;
+	dev->buf_size = BULK_BUFFER_SIZE;
+
+	dev_dbg(dev->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(dev->dev, "alloc buf=%d failed\n",
+					dev->buf_num);
+			hackrf_free_stream_bufs(dev);
+			return -ENOMEM;
+		}
+
+		dev_dbg(dev->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]);
+		dev->flags |= USB_STATE_URB_BUF;
+	}
+
+	return 0;
+}
+
+static int hackrf_free_urbs(struct hackrf_dev *dev)
+{
+	int i;
+
+	hackrf_kill_urbs(dev);
+
+	for (i = dev->urbs_initialized - 1; i >= 0; i--) {
+		if (dev->urb_list[i]) {
+			dev_dbg(dev->dev, "free urb=%d\n", i);
+			/* free the URBs */
+			usb_free_urb(dev->urb_list[i]);
+		}
+	}
+	dev->urbs_initialized = 0;
+
+	return 0;
+}
+
+static int hackrf_alloc_urbs(struct hackrf_dev *dev, bool rcv)
+{
+	int i, j;
+	unsigned int pipe;
+	usb_complete_t complete;
+
+	if (rcv) {
+		pipe = usb_rcvbulkpipe(dev->udev, 0x81);
+		complete = &hackrf_urb_complete_in;
+	} else {
+		pipe = usb_sndbulkpipe(dev->udev, 0x02);
+		complete = &hackrf_urb_complete_out;
+	}
+
+	/* allocate the URBs */
+	for (i = 0; i < MAX_BULK_BUFS; i++) {
+		dev_dbg(dev->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]);
+			return -ENOMEM;
+		}
+		usb_fill_bulk_urb(dev->urb_list[i],
+				dev->udev,
+				pipe,
+				dev->buf_list[i],
+				BULK_BUFFER_SIZE,
+				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;
+}
+
+/* The user yanked out the cable... */
+static void hackrf_disconnect(struct usb_interface *intf)
+{
+	struct v4l2_device *v = usb_get_intfdata(intf);
+	struct hackrf_dev *dev = container_of(v, struct hackrf_dev, v4l2_dev);
+
+	dev_dbg(dev->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->tx_vdev);
+	video_unregister_device(&dev->rx_vdev);
+	mutex_unlock(&dev->v4l2_lock);
+	mutex_unlock(&dev->vb_queue_lock);
+
+	v4l2_device_put(&dev->v4l2_dev);
+}
+
+/* Videobuf2 operations */
+static void hackrf_return_all_buffers(struct vb2_queue *vq,
+				      enum vb2_buffer_state state)
+{
+	struct hackrf_dev *dev = vb2_get_drv_priv(vq);
+	struct usb_interface *intf = dev->intf;
+	struct hackrf_buffer *buffer, *node;
+	struct list_head *buffer_list;
+	unsigned long flags;
+
+	dev_dbg(&intf->dev, "\n");
+
+	if (vq->type == V4L2_BUF_TYPE_SDR_CAPTURE)
+		buffer_list = &dev->rx_buffer_list;
+	else
+		buffer_list = &dev->tx_buffer_list;
+
+	spin_lock_irqsave(&dev->buffer_list_lock, flags);
+	list_for_each_entry_safe(buffer, node, buffer_list, list) {
+		dev_dbg(&intf->dev, "list_for_each_entry_safe\n");
+		vb2_buffer_done(&buffer->vb.vb2_buf, state);
+		list_del(&buffer->list);
+	}
+	spin_unlock_irqrestore(&dev->buffer_list_lock, flags);
+}
+
+static int hackrf_queue_setup(struct vb2_queue *vq,
+		unsigned int *nbuffers,
+		unsigned int *nplanes, unsigned int sizes[], struct device *alloc_devs[])
+{
+	struct hackrf_dev *dev = vb2_get_drv_priv(vq);
+	unsigned int q_num_bufs = vb2_get_num_buffers(vq);
+
+	dev_dbg(dev->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(dev->dev, "nbuffers=%d sizes[0]=%d\n", *nbuffers, sizes[0]);
+	return 0;
+}
+
+static void hackrf_buf_queue(struct vb2_buffer *vb)
+{
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct vb2_queue *vq = vb->vb2_queue;
+	struct hackrf_dev *dev = vb2_get_drv_priv(vq);
+	struct hackrf_buffer *buffer = container_of(vbuf, struct hackrf_buffer, vb);
+	struct list_head *buffer_list;
+	unsigned long flags;
+
+	dev_dbg_ratelimited(&dev->intf->dev, "\n");
+
+	if (vq->type == V4L2_BUF_TYPE_SDR_CAPTURE)
+		buffer_list = &dev->rx_buffer_list;
+	else
+		buffer_list = &dev->tx_buffer_list;
+
+	spin_lock_irqsave(&dev->buffer_list_lock, flags);
+	list_add_tail(&buffer->list, buffer_list);
+	spin_unlock_irqrestore(&dev->buffer_list_lock, flags);
+}
+
+static int hackrf_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+	struct hackrf_dev *dev = vb2_get_drv_priv(vq);
+	struct usb_interface *intf = dev->intf;
+	int ret;
+	unsigned int mode;
+
+	dev_dbg(&intf->dev, "count=%i\n", count);
+
+	mutex_lock(&dev->v4l2_lock);
+
+	/* Allow only RX or TX, not both same time */
+	if (vq->type == V4L2_BUF_TYPE_SDR_CAPTURE) {
+		if (test_bit(TX_ON, &dev->flags)) {
+			ret = -EBUSY;
+			goto err_hackrf_return_all_buffers;
+		}
+
+		mode = 1;
+		set_bit(RX_ON, &dev->flags);
+	} else {
+		if (test_bit(RX_ON, &dev->flags)) {
+			ret = -EBUSY;
+			goto err_hackrf_return_all_buffers;
+		}
+
+		mode = 2;
+		set_bit(TX_ON, &dev->flags);
+	}
+
+	dev->sequence = 0;
+
+	ret = hackrf_alloc_stream_bufs(dev);
+	if (ret)
+		goto err;
+
+	ret = hackrf_alloc_urbs(dev, (mode == 1));
+	if (ret)
+		goto err;
+
+	ret = hackrf_submit_urbs(dev);
+	if (ret)
+		goto err;
+
+	ret = hackrf_set_params(dev);
+	if (ret)
+		goto err;
+
+	/* start hardware streaming */
+	ret = hackrf_ctrl_msg(dev, CMD_SET_TRANSCEIVER_MODE, mode, 0, NULL, 0);
+	if (ret)
+		goto err;
+
+	mutex_unlock(&dev->v4l2_lock);
+
+	return 0;
+err:
+	hackrf_kill_urbs(dev);
+	hackrf_free_urbs(dev);
+	hackrf_free_stream_bufs(dev);
+	clear_bit(RX_ON, &dev->flags);
+	clear_bit(TX_ON, &dev->flags);
+err_hackrf_return_all_buffers:
+	hackrf_return_all_buffers(vq, VB2_BUF_STATE_QUEUED);
+	mutex_unlock(&dev->v4l2_lock);
+	dev_dbg(&intf->dev, "failed=%d\n", ret);
+	return ret;
+}
+
+static void hackrf_stop_streaming(struct vb2_queue *vq)
+{
+	struct hackrf_dev *dev = vb2_get_drv_priv(vq);
+	struct usb_interface *intf = dev->intf;
+
+	dev_dbg(&intf->dev, "\n");
+
+	mutex_lock(&dev->v4l2_lock);
+
+	/* stop hardware streaming */
+	hackrf_ctrl_msg(dev, CMD_SET_TRANSCEIVER_MODE, 0, 0, NULL, 0);
+
+	hackrf_kill_urbs(dev);
+	hackrf_free_urbs(dev);
+	hackrf_free_stream_bufs(dev);
+
+	hackrf_return_all_buffers(vq, VB2_BUF_STATE_ERROR);
+
+	if (vq->type == V4L2_BUF_TYPE_SDR_CAPTURE)
+		clear_bit(RX_ON, &dev->flags);
+	else
+		clear_bit(TX_ON, &dev->flags);
+
+	mutex_unlock(&dev->v4l2_lock);
+}
+
+static const struct vb2_ops hackrf_vb2_ops = {
+	.queue_setup            = hackrf_queue_setup,
+	.buf_queue              = hackrf_buf_queue,
+	.start_streaming        = hackrf_start_streaming,
+	.stop_streaming         = hackrf_stop_streaming,
+};
+
+static int hackrf_querycap(struct file *file, void *fh,
+		struct v4l2_capability *cap)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+	struct usb_interface *intf = dev->intf;
+
+	dev_dbg(&intf->dev, "\n");
+
+	cap->capabilities = V4L2_CAP_SDR_CAPTURE | V4L2_CAP_TUNER |
+			    V4L2_CAP_SDR_OUTPUT | V4L2_CAP_MODULATOR |
+			    V4L2_CAP_STREAMING | V4L2_CAP_READWRITE |
+			    V4L2_CAP_DEVICE_CAPS;
+	strscpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
+	strscpy(cap->card, dev->rx_vdev.name, sizeof(cap->card));
+	usb_make_path(dev->udev, cap->bus_info, sizeof(cap->bus_info));
+
+	return 0;
+}
+
+static int hackrf_s_fmt_sdr(struct file *file, void *priv,
+			    struct v4l2_format *f)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+	struct video_device *vdev = video_devdata(file);
+	struct vb2_queue *q;
+	int i;
+
+	dev_dbg(dev->dev, "pixelformat fourcc %4.4s\n",
+			(char *)&f->fmt.sdr.pixelformat);
+
+	if (vdev->vfl_dir == VFL_DIR_RX)
+		q = &dev->rx_vb2_queue;
+	else
+		q = &dev->tx_vb2_queue;
+
+	if (vb2_is_busy(q))
+		return -EBUSY;
+
+	for (i = 0; i < NUM_FORMATS; i++) {
+		if (f->fmt.sdr.pixelformat == formats[i].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 hackrf_g_fmt_sdr(struct file *file, void *priv,
+			    struct v4l2_format *f)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+
+	dev_dbg(dev->dev, "pixelformat fourcc %4.4s\n",
+			(char *)&dev->pixelformat);
+
+	f->fmt.sdr.pixelformat = dev->pixelformat;
+	f->fmt.sdr.buffersize = dev->buffersize;
+
+	return 0;
+}
+
+static int hackrf_try_fmt_sdr(struct file *file, void *priv,
+			      struct v4l2_format *f)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+	int i;
+
+	dev_dbg(dev->dev, "pixelformat fourcc %4.4s\n",
+			(char *)&f->fmt.sdr.pixelformat);
+
+	for (i = 0; i < 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 int hackrf_enum_fmt_sdr(struct file *file, void *priv,
+			       struct v4l2_fmtdesc *f)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+
+	dev_dbg(dev->dev, "index=%d\n", f->index);
+
+	if (f->index >= NUM_FORMATS)
+		return -EINVAL;
+
+	f->pixelformat = formats[f->index].pixelformat;
+
+	return 0;
+}
+
+static int hackrf_s_tuner(struct file *file, void *priv,
+		const struct v4l2_tuner *v)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+	int ret;
+
+	dev_dbg(dev->dev, "index=%d\n", v->index);
+
+	if (v->index == 0)
+		ret = 0;
+	else if (v->index == 1)
+		ret = 0;
+	else
+		ret = -EINVAL;
+
+	return ret;
+}
+
+static int hackrf_g_tuner(struct file *file, void *priv, struct v4l2_tuner *v)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+	int ret;
+
+	dev_dbg(dev->dev, "index=%d\n", v->index);
+
+	if (v->index == 0) {
+		strscpy(v->name, "HackRF ADC", sizeof(v->name));
+		v->type = V4L2_TUNER_SDR;
+		v->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
+		v->rangelow  = bands_adc_dac[0].rangelow;
+		v->rangehigh = bands_adc_dac[0].rangehigh;
+		ret = 0;
+	} else if (v->index == 1) {
+		strscpy(v->name, "HackRF RF", sizeof(v->name));
+		v->type = V4L2_TUNER_RF;
+		v->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
+		v->rangelow  = bands_rx_tx[0].rangelow;
+		v->rangehigh = bands_rx_tx[0].rangehigh;
+		ret = 0;
+	} else {
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int hackrf_s_modulator(struct file *file, void *fh,
+			      const struct v4l2_modulator *a)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+
+	dev_dbg(dev->dev, "index=%d\n", a->index);
+
+	return a->index > 1 ? -EINVAL : 0;
+}
+
+static int hackrf_g_modulator(struct file *file, void *fh,
+			      struct v4l2_modulator *a)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+	int ret;
+
+	dev_dbg(dev->dev, "index=%d\n", a->index);
+
+	if (a->index == 0) {
+		strscpy(a->name, "HackRF DAC", sizeof(a->name));
+		a->type = V4L2_TUNER_SDR;
+		a->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
+		a->rangelow  = bands_adc_dac[0].rangelow;
+		a->rangehigh = bands_adc_dac[0].rangehigh;
+		ret = 0;
+	} else if (a->index == 1) {
+		strscpy(a->name, "HackRF RF", sizeof(a->name));
+		a->type = V4L2_TUNER_RF;
+		a->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
+		a->rangelow  = bands_rx_tx[0].rangelow;
+		a->rangehigh = bands_rx_tx[0].rangehigh;
+		ret = 0;
+	} else {
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int hackrf_s_frequency(struct file *file, void *priv,
+		const struct v4l2_frequency *f)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+	struct usb_interface *intf = dev->intf;
+	struct video_device *vdev = video_devdata(file);
+	int ret;
+	unsigned int uitmp;
+
+	dev_dbg(&intf->dev, "tuner=%d type=%d frequency=%u\n",
+			f->tuner, f->type, f->frequency);
+
+	if (f->tuner == 0) {
+		uitmp = clamp(f->frequency, bands_adc_dac[0].rangelow,
+			      bands_adc_dac[0].rangehigh);
+		if (vdev->vfl_dir == VFL_DIR_RX) {
+			dev->f_adc = uitmp;
+			set_bit(RX_ADC_FREQUENCY, &dev->flags);
+		} else {
+			dev->f_dac = uitmp;
+			set_bit(TX_DAC_FREQUENCY, &dev->flags);
+		}
+	} else if (f->tuner == 1) {
+		uitmp = clamp(f->frequency, bands_rx_tx[0].rangelow,
+			      bands_rx_tx[0].rangehigh);
+		if (vdev->vfl_dir == VFL_DIR_RX) {
+			dev->f_rx = uitmp;
+			set_bit(RX_RF_FREQUENCY, &dev->flags);
+		} else {
+			dev->f_tx = uitmp;
+			set_bit(TX_RF_FREQUENCY, &dev->flags);
+		}
+	} else {
+		ret = -EINVAL;
+		goto err;
+	}
+
+	ret = hackrf_set_params(dev);
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	dev_dbg(&intf->dev, "failed=%d\n", ret);
+	return ret;
+}
+
+static int hackrf_g_frequency(struct file *file, void *priv,
+		struct v4l2_frequency *f)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+	struct usb_interface *intf = dev->intf;
+	struct video_device *vdev = video_devdata(file);
+	int ret;
+
+	dev_dbg(dev->dev, "tuner=%d type=%d\n", f->tuner, f->type);
+
+	if (f->tuner == 0) {
+		f->type = V4L2_TUNER_SDR;
+		if (vdev->vfl_dir == VFL_DIR_RX)
+			f->frequency = dev->f_adc;
+		else
+			f->frequency = dev->f_dac;
+	} else if (f->tuner == 1) {
+		f->type = V4L2_TUNER_RF;
+		if (vdev->vfl_dir == VFL_DIR_RX)
+			f->frequency = dev->f_rx;
+		else
+			f->frequency = dev->f_tx;
+	} else {
+		ret = -EINVAL;
+		goto err;
+	}
+
+	return 0;
+err:
+	dev_dbg(&intf->dev, "failed=%d\n", ret);
+	return ret;
+}
+
+static int hackrf_enum_freq_bands(struct file *file, void *priv,
+		struct v4l2_frequency_band *band)
+{
+	struct hackrf_dev *dev = video_drvdata(file);
+	int ret;
+
+	dev_dbg(dev->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_dac)) {
+			ret = -EINVAL;
+		} else {
+			*band = bands_adc_dac[band->index];
+			ret = 0;
+		}
+	} else if (band->tuner == 1) {
+		if (band->index >= ARRAY_SIZE(bands_rx_tx)) {
+			ret = -EINVAL;
+		} else {
+			*band = bands_rx_tx[band->index];
+			ret = 0;
+		}
+	} else {
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static const struct v4l2_ioctl_ops hackrf_ioctl_ops = {
+	.vidioc_querycap          = hackrf_querycap,
+
+	.vidioc_s_fmt_sdr_cap     = hackrf_s_fmt_sdr,
+	.vidioc_g_fmt_sdr_cap     = hackrf_g_fmt_sdr,
+	.vidioc_enum_fmt_sdr_cap  = hackrf_enum_fmt_sdr,
+	.vidioc_try_fmt_sdr_cap   = hackrf_try_fmt_sdr,
+
+	.vidioc_s_fmt_sdr_out     = hackrf_s_fmt_sdr,
+	.vidioc_g_fmt_sdr_out     = hackrf_g_fmt_sdr,
+	.vidioc_enum_fmt_sdr_out  = hackrf_enum_fmt_sdr,
+	.vidioc_try_fmt_sdr_out   = hackrf_try_fmt_sdr,
+
+	.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_expbuf            = vb2_ioctl_expbuf,
+
+	.vidioc_streamon          = vb2_ioctl_streamon,
+	.vidioc_streamoff         = vb2_ioctl_streamoff,
+
+	.vidioc_s_tuner           = hackrf_s_tuner,
+	.vidioc_g_tuner           = hackrf_g_tuner,
+
+	.vidioc_s_modulator       = hackrf_s_modulator,
+	.vidioc_g_modulator       = hackrf_g_modulator,
+
+	.vidioc_s_frequency       = hackrf_s_frequency,
+	.vidioc_g_frequency       = hackrf_g_frequency,
+	.vidioc_enum_freq_bands   = hackrf_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 hackrf_fops = {
+	.owner                    = THIS_MODULE,
+	.open                     = v4l2_fh_open,
+	.release                  = vb2_fop_release,
+	.read                     = vb2_fop_read,
+	.write                    = vb2_fop_write,
+	.poll                     = vb2_fop_poll,
+	.mmap                     = vb2_fop_mmap,
+	.unlocked_ioctl           = video_ioctl2,
+};
+
+static const struct video_device hackrf_template = {
+	.name                     = "HackRF One",
+	.release                  = video_device_release_empty,
+	.fops                     = &hackrf_fops,
+	.ioctl_ops                = &hackrf_ioctl_ops,
+};
+
+static void hackrf_video_release(struct v4l2_device *v)
+{
+	struct hackrf_dev *dev = container_of(v, struct hackrf_dev, v4l2_dev);
+
+	dev_dbg(dev->dev, "\n");
+
+	v4l2_ctrl_handler_free(&dev->rx_ctrl_handler);
+	v4l2_ctrl_handler_free(&dev->tx_ctrl_handler);
+	v4l2_device_unregister(&dev->v4l2_dev);
+	kfree(dev);
+}
+
+static int hackrf_s_ctrl_rx(struct v4l2_ctrl *ctrl)
+{
+	struct hackrf_dev *dev = container_of(ctrl->handler,
+			struct hackrf_dev, rx_ctrl_handler);
+	struct usb_interface *intf = dev->intf;
+	int ret;
+
+	switch (ctrl->id) {
+	case V4L2_CID_RF_TUNER_BANDWIDTH_AUTO:
+	case V4L2_CID_RF_TUNER_BANDWIDTH:
+		set_bit(RX_BANDWIDTH, &dev->flags);
+		break;
+	case  V4L2_CID_RF_TUNER_RF_GAIN:
+		set_bit(RX_RF_GAIN, &dev->flags);
+		break;
+	case  V4L2_CID_RF_TUNER_LNA_GAIN:
+		set_bit(RX_LNA_GAIN, &dev->flags);
+		break;
+	case  V4L2_CID_RF_TUNER_IF_GAIN:
+		set_bit(RX_IF_GAIN, &dev->flags);
+		break;
+	default:
+		dev_dbg(&intf->dev, "unknown ctrl: id=%d name=%s\n",
+			ctrl->id, ctrl->name);
+		ret = -EINVAL;
+		goto err;
+	}
+
+	ret = hackrf_set_params(dev);
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	dev_dbg(&intf->dev, "failed=%d\n", ret);
+	return ret;
+}
+
+static int hackrf_s_ctrl_tx(struct v4l2_ctrl *ctrl)
+{
+	struct hackrf_dev *dev = container_of(ctrl->handler,
+			struct hackrf_dev, tx_ctrl_handler);
+	struct usb_interface *intf = dev->intf;
+	int ret;
+
+	switch (ctrl->id) {
+	case V4L2_CID_RF_TUNER_BANDWIDTH_AUTO:
+	case V4L2_CID_RF_TUNER_BANDWIDTH:
+		set_bit(TX_BANDWIDTH, &dev->flags);
+		break;
+	case  V4L2_CID_RF_TUNER_LNA_GAIN:
+		set_bit(TX_LNA_GAIN, &dev->flags);
+		break;
+	case  V4L2_CID_RF_TUNER_RF_GAIN:
+		set_bit(TX_RF_GAIN, &dev->flags);
+		break;
+	default:
+		dev_dbg(&intf->dev, "unknown ctrl: id=%d name=%s\n",
+			ctrl->id, ctrl->name);
+		ret = -EINVAL;
+		goto err;
+	}
+
+	ret = hackrf_set_params(dev);
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	dev_dbg(&intf->dev, "failed=%d\n", ret);
+	return ret;
+}
+
+static const struct v4l2_ctrl_ops hackrf_ctrl_ops_rx = {
+	.s_ctrl = hackrf_s_ctrl_rx,
+};
+
+static const struct v4l2_ctrl_ops hackrf_ctrl_ops_tx = {
+	.s_ctrl = hackrf_s_ctrl_tx,
+};
+
+static int hackrf_probe(struct usb_interface *intf,
+		const struct usb_device_id *id)
+{
+	struct hackrf_dev *dev;
+	int ret;
+	u8 u8tmp, buf[BUF_SIZE];
+
+	dev = kzalloc_obj(*dev);
+	if (!dev) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	mutex_init(&dev->v4l2_lock);
+	mutex_init(&dev->vb_queue_lock);
+	spin_lock_init(&dev->buffer_list_lock);
+	INIT_LIST_HEAD(&dev->rx_buffer_list);
+	INIT_LIST_HEAD(&dev->tx_buffer_list);
+	dev->intf = intf;
+	dev->dev = &intf->dev;
+	dev->udev = interface_to_usbdev(intf);
+	dev->pixelformat = formats[0].pixelformat;
+	dev->buffersize = formats[0].buffersize;
+	dev->f_adc = bands_adc_dac[0].rangelow;
+	dev->f_dac = bands_adc_dac[0].rangelow;
+	dev->f_rx = bands_rx_tx[0].rangelow;
+	dev->f_tx = bands_rx_tx[0].rangelow;
+	set_bit(RX_ADC_FREQUENCY, &dev->flags);
+	set_bit(TX_DAC_FREQUENCY, &dev->flags);
+	set_bit(RX_RF_FREQUENCY, &dev->flags);
+	set_bit(TX_RF_FREQUENCY, &dev->flags);
+
+	/* Detect device */
+	ret = hackrf_ctrl_msg(dev, CMD_BOARD_ID_READ, 0, 0, &u8tmp, 1);
+	if (ret == 0)
+		ret = hackrf_ctrl_msg(dev, CMD_VERSION_STRING_READ, 0, 0,
+				buf, BUF_SIZE);
+	if (ret) {
+		dev_err(dev->dev, "Could not detect board\n");
+		goto err_kfree;
+	}
+
+	buf[BUF_SIZE - 1] = '\0';
+	dev_info(dev->dev, "Board ID: %02x\n", u8tmp);
+	dev_info(dev->dev, "Firmware version: %s\n", buf);
+
+	/* Init vb2 queue structure for receiver */
+	dev->rx_vb2_queue.type = V4L2_BUF_TYPE_SDR_CAPTURE;
+	dev->rx_vb2_queue.io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF |
+				     VB2_READ;
+	dev->rx_vb2_queue.ops = &hackrf_vb2_ops;
+	dev->rx_vb2_queue.mem_ops = &vb2_vmalloc_memops;
+	dev->rx_vb2_queue.drv_priv = dev;
+	dev->rx_vb2_queue.buf_struct_size = sizeof(struct hackrf_buffer);
+	dev->rx_vb2_queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+	dev->rx_vb2_queue.lock = &dev->vb_queue_lock;
+	ret = vb2_queue_init(&dev->rx_vb2_queue);
+	if (ret) {
+		dev_err(dev->dev, "Could not initialize rx vb2 queue\n");
+		goto err_kfree;
+	}
+
+	/* Init vb2 queue structure for transmitter */
+	dev->tx_vb2_queue.type = V4L2_BUF_TYPE_SDR_OUTPUT;
+	dev->tx_vb2_queue.io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF |
+				     VB2_WRITE;
+	dev->tx_vb2_queue.ops = &hackrf_vb2_ops;
+	dev->tx_vb2_queue.mem_ops = &vb2_vmalloc_memops;
+	dev->tx_vb2_queue.drv_priv = dev;
+	dev->tx_vb2_queue.buf_struct_size = sizeof(struct hackrf_buffer);
+	dev->tx_vb2_queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+	dev->tx_vb2_queue.lock = &dev->vb_queue_lock;
+	ret = vb2_queue_init(&dev->tx_vb2_queue);
+	if (ret) {
+		dev_err(dev->dev, "Could not initialize tx vb2 queue\n");
+		goto err_kfree;
+	}
+
+	/* Register controls for receiver */
+	v4l2_ctrl_handler_init(&dev->rx_ctrl_handler, 5);
+	dev->rx_bandwidth_auto = v4l2_ctrl_new_std(&dev->rx_ctrl_handler,
+		&hackrf_ctrl_ops_rx, V4L2_CID_RF_TUNER_BANDWIDTH_AUTO,
+		0, 1, 0, 1);
+	dev->rx_bandwidth = v4l2_ctrl_new_std(&dev->rx_ctrl_handler,
+		&hackrf_ctrl_ops_rx, V4L2_CID_RF_TUNER_BANDWIDTH,
+		1750000, 28000000, 50000, 1750000);
+	v4l2_ctrl_auto_cluster(2, &dev->rx_bandwidth_auto, 0, false);
+	dev->rx_rf_gain = v4l2_ctrl_new_std(&dev->rx_ctrl_handler,
+		&hackrf_ctrl_ops_rx, V4L2_CID_RF_TUNER_RF_GAIN, 0, 12, 12, 0);
+	dev->rx_lna_gain = v4l2_ctrl_new_std(&dev->rx_ctrl_handler,
+		&hackrf_ctrl_ops_rx, V4L2_CID_RF_TUNER_LNA_GAIN, 0, 40, 8, 0);
+	dev->rx_if_gain = v4l2_ctrl_new_std(&dev->rx_ctrl_handler,
+		&hackrf_ctrl_ops_rx, V4L2_CID_RF_TUNER_IF_GAIN, 0, 62, 2, 0);
+	if (dev->rx_ctrl_handler.error) {
+		ret = dev->rx_ctrl_handler.error;
+		dev_err(dev->dev, "Could not initialize controls\n");
+		goto err_v4l2_ctrl_handler_free_rx;
+	}
+	v4l2_ctrl_grab(dev->rx_rf_gain, !hackrf_enable_rf_gain_ctrl);
+	v4l2_ctrl_handler_setup(&dev->rx_ctrl_handler);
+
+	/* Register controls for transmitter */
+	v4l2_ctrl_handler_init(&dev->tx_ctrl_handler, 4);
+	dev->tx_bandwidth_auto = v4l2_ctrl_new_std(&dev->tx_ctrl_handler,
+		&hackrf_ctrl_ops_tx, V4L2_CID_RF_TUNER_BANDWIDTH_AUTO,
+		0, 1, 0, 1);
+	dev->tx_bandwidth = v4l2_ctrl_new_std(&dev->tx_ctrl_handler,
+		&hackrf_ctrl_ops_tx, V4L2_CID_RF_TUNER_BANDWIDTH,
+		1750000, 28000000, 50000, 1750000);
+	v4l2_ctrl_auto_cluster(2, &dev->tx_bandwidth_auto, 0, false);
+	dev->tx_lna_gain = v4l2_ctrl_new_std(&dev->tx_ctrl_handler,
+		&hackrf_ctrl_ops_tx, V4L2_CID_RF_TUNER_LNA_GAIN, 0, 47, 1, 0);
+	dev->tx_rf_gain = v4l2_ctrl_new_std(&dev->tx_ctrl_handler,
+		&hackrf_ctrl_ops_tx, V4L2_CID_RF_TUNER_RF_GAIN, 0, 15, 15, 0);
+	if (dev->tx_ctrl_handler.error) {
+		ret = dev->tx_ctrl_handler.error;
+		dev_err(dev->dev, "Could not initialize controls\n");
+		goto err_v4l2_ctrl_handler_free_tx;
+	}
+	v4l2_ctrl_grab(dev->tx_rf_gain, !hackrf_enable_rf_gain_ctrl);
+	v4l2_ctrl_handler_setup(&dev->tx_ctrl_handler);
+
+	/* Register the v4l2_device structure */
+	dev->v4l2_dev.release = hackrf_video_release;
+	ret = v4l2_device_register(&intf->dev, &dev->v4l2_dev);
+	if (ret) {
+		dev_err(dev->dev, "Failed to register v4l2-device (%d)\n", ret);
+		goto err_v4l2_ctrl_handler_free_tx;
+	}
+
+	/* Init video_device structure for receiver */
+	dev->rx_vdev = hackrf_template;
+	dev->rx_vdev.queue = &dev->rx_vb2_queue;
+	dev->rx_vdev.v4l2_dev = &dev->v4l2_dev;
+	dev->rx_vdev.ctrl_handler = &dev->rx_ctrl_handler;
+	dev->rx_vdev.lock = &dev->v4l2_lock;
+	dev->rx_vdev.vfl_dir = VFL_DIR_RX;
+	dev->rx_vdev.device_caps = V4L2_CAP_STREAMING | V4L2_CAP_READWRITE |
+				   V4L2_CAP_SDR_CAPTURE | V4L2_CAP_TUNER;
+	video_set_drvdata(&dev->rx_vdev, dev);
+	ret = video_register_device(&dev->rx_vdev, VFL_TYPE_SDR, -1);
+	if (ret) {
+		dev_err(dev->dev,
+			"Failed to register as video device (%d)\n", ret);
+		goto err_v4l2_device_put;
+	}
+	dev_info(dev->dev, "Registered as %s\n",
+		 video_device_node_name(&dev->rx_vdev));
+
+	/* Init video_device structure for transmitter */
+	dev->tx_vdev = hackrf_template;
+	dev->tx_vdev.queue = &dev->tx_vb2_queue;
+	dev->tx_vdev.v4l2_dev = &dev->v4l2_dev;
+	dev->tx_vdev.ctrl_handler = &dev->tx_ctrl_handler;
+	dev->tx_vdev.lock = &dev->v4l2_lock;
+	dev->tx_vdev.vfl_dir = VFL_DIR_TX;
+	dev->tx_vdev.device_caps = V4L2_CAP_STREAMING | V4L2_CAP_READWRITE |
+				   V4L2_CAP_SDR_OUTPUT | V4L2_CAP_MODULATOR;
+	video_set_drvdata(&dev->tx_vdev, dev);
+	ret = video_register_device(&dev->tx_vdev, VFL_TYPE_SDR, -1);
+	if (ret) {
+		dev_err(dev->dev,
+			"Failed to register as video device (%d)\n", ret);
+		goto err_video_unregister_device_rx;
+	}
+	dev_info(dev->dev, "Registered as %s\n",
+		 video_device_node_name(&dev->tx_vdev));
+
+	dev_notice(dev->dev, "SDR API is still slightly experimental and functionality changes may follow\n");
+	return 0;
+err_video_unregister_device_rx:
+	video_unregister_device(&dev->rx_vdev);
+err_v4l2_device_put:
+	v4l2_device_put(&dev->v4l2_dev);
+	return ret;
+err_v4l2_ctrl_handler_free_tx:
+	v4l2_ctrl_handler_free(&dev->tx_ctrl_handler);
+err_v4l2_ctrl_handler_free_rx:
+	v4l2_ctrl_handler_free(&dev->rx_ctrl_handler);
+err_kfree:
+	kfree(dev);
+err:
+	dev_dbg(&intf->dev, "failed=%d\n", ret);
+	return ret;
+}
+
+/* USB device ID list */
+static const struct usb_device_id hackrf_id_table[] = {
+	{ USB_DEVICE(0x1d50, 0x6089) }, /* HackRF One */
+	{ }
+};
+MODULE_DEVICE_TABLE(usb, hackrf_id_table);
+
+/* USB subsystem interface */
+static struct usb_driver hackrf_driver = {
+	.name                     = KBUILD_MODNAME,
+	.probe                    = hackrf_probe,
+	.disconnect               = hackrf_disconnect,
+	.id_table                 = hackrf_id_table,
+};
+
+module_usb_driver(hackrf_driver);
+
+MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
+MODULE_DESCRIPTION("HackRF");
+MODULE_LICENSE("GPL");