[media] radio-mr800: add hardware seek support

Added hardware seek support based on information gleaned from the
GPLv2 driver available here:
http://sourceforge.net/projects/av-usbradio/

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/radio/radio-mr800.c

@@ -103,13 +103,17 @@ devices, that would be 76 and 91.  */
  * List isn't full and will be updated with implementation of new functions
  */
 #define AMRADIO_SET_FREQ	0xa4
+#define AMRADIO_GET_READY_FLAG	0xa5
 #define AMRADIO_GET_SIGNAL	0xa7
+#define AMRADIO_GET_FREQ	0xa8
+#define AMRADIO_SET_SEARCH_UP	0xa9
+#define AMRADIO_SET_SEARCH_DOWN	0xaa
 #define AMRADIO_SET_MUTE	0xab
+#define AMRADIO_SET_RIGHT_MUTE	0xac
+#define AMRADIO_SET_LEFT_MUTE	0xad
 #define AMRADIO_SET_MONO	0xae
-
-/* Comfortable defines for amradio_set_mute */
-#define AMRADIO_START		0x00
-#define AMRADIO_STOP		0x01
+#define AMRADIO_SET_SEARCH_LVL	0xb0
+#define AMRADIO_STOP_SEARCH	0xb1
 
 /* Comfortable defines for amradio_set_stereo */
 #define WANT_STEREO		0x00
@@ -129,7 +133,7 @@ struct amradio_device {
 	struct v4l2_device v4l2_dev;
 	struct v4l2_ctrl_handler hdl;
 
-	unsigned char *buffer;
+	u8 *buffer;
 	struct mutex lock;	/* buffer locking */
 	int curfreq;
 	int stereo;
@@ -141,8 +145,8 @@ static inline struct amradio_device *to_amradio_dev(struct v4l2_device *v4l2_dev
 	return container_of(v4l2_dev, struct amradio_device, v4l2_dev);
 }
 
-/* switch on/off the radio. Send 8 bytes to device */
-static int amradio_set_mute(struct amradio_device *radio, char argument)
+static int amradio_send_cmd(struct amradio_device *radio, u8 cmd, u8 arg,
+		u8 *extra, u8 extralen, bool reply)
 {
 	int retval;
 	int size;
@@ -150,117 +154,89 @@ static int amradio_set_mute(struct amradio_device *radio, char argument)
 	radio->buffer[0] = 0x00;
 	radio->buffer[1] = 0x55;
 	radio->buffer[2] = 0xaa;
-	radio->buffer[3] = 0x00;
-	radio->buffer[4] = AMRADIO_SET_MUTE;
-	radio->buffer[5] = argument;
+	radio->buffer[3] = extralen;
+	radio->buffer[4] = cmd;
+	radio->buffer[5] = arg;
 	radio->buffer[6] = 0x00;
-	radio->buffer[7] = 0x00;
+	radio->buffer[7] = extra || reply ? 8 : 0;
 
 	retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
-		(void *) (radio->buffer), BUFFER_LENGTH, &size, USB_TIMEOUT);
+		radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
 
 	if (retval < 0 || size != BUFFER_LENGTH) {
-		amradio_dev_warn(&radio->vdev.dev, "set mute failed\n");
-		return retval < 0 ? retval : -EIO;
+		if (video_is_registered(&radio->vdev))
+			amradio_dev_warn(&radio->vdev.dev,
+					"cmd %02x failed\n", cmd);
+		return retval ? retval : -EIO;
 	}
-	radio->muted = argument;
-	return 0;
+	if (!extra && !reply)
+		return 0;
+
+	if (extra) {
+		memcpy(radio->buffer, extra, extralen);
+		memset(radio->buffer + extralen, 0, 8 - extralen);
+		retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
+			radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
+	} else {
+		memset(radio->buffer, 0, 8);
+		retval = usb_bulk_msg(radio->usbdev, usb_rcvbulkpipe(radio->usbdev, 0x81),
+			radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
+	}
+	if (retval == 0 && size == BUFFER_LENGTH)
+		return 0;
+	if (video_is_registered(&radio->vdev) && cmd != AMRADIO_GET_READY_FLAG)
+		amradio_dev_warn(&radio->vdev.dev, "follow-up to cmd %02x failed\n", cmd);
+	return retval ? retval : -EIO;
+}
+
+/* switch on/off the radio. Send 8 bytes to device */
+static int amradio_set_mute(struct amradio_device *radio, bool mute)
+{
+	int ret = amradio_send_cmd(radio,
+			AMRADIO_SET_MUTE, mute, NULL, 0, false);
+
+	if (!ret)
+		radio->muted = mute;
+	return ret;
 }
 
 /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
-static int amradio_setfreq(struct amradio_device *radio, int freq)
+static int amradio_set_freq(struct amradio_device *radio, int freq)
 {
 	unsigned short freq_send = 0x10 + (freq >> 3) / 25;
+	u8 buf[3];
 	int retval;
-	int size;
-
-	radio->buffer[0] = 0x00;
-	radio->buffer[1] = 0x55;
-	radio->buffer[2] = 0xaa;
-	radio->buffer[3] = 0x03;
-	radio->buffer[4] = AMRADIO_SET_FREQ;
-	radio->buffer[5] = 0x00;
-	radio->buffer[6] = 0x00;
-	radio->buffer[7] = 0x08;
-
-	retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
-		(void *) (radio->buffer), BUFFER_LENGTH, &size, USB_TIMEOUT);
-
-	if (retval < 0 || size != BUFFER_LENGTH)
-		goto out;
 
 	/* frequency is calculated from freq_send and placed in first 2 bytes */
-	radio->buffer[0] = (freq_send >> 8) & 0xff;
-	radio->buffer[1] = freq_send & 0xff;
-	radio->buffer[2] = 0x01;
-	radio->buffer[3] = 0x00;
-	radio->buffer[4] = 0x00;
-	/* 5 and 6 bytes of buffer already = 0x00 */
-	radio->buffer[7] = 0x00;
-
-	retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
-		(void *) (radio->buffer), BUFFER_LENGTH, &size, USB_TIMEOUT);
+	buf[0] = (freq_send >> 8) & 0xff;
+	buf[1] = freq_send & 0xff;
+	buf[2] = 0x01;
 
-	if (retval >= 0 && size == BUFFER_LENGTH) {
-		radio->curfreq = freq;
-		return 0;
-	}
-
-out:
-	amradio_dev_warn(&radio->vdev.dev, "set frequency failed\n");
-	return retval < 0 ? retval : -EIO;
+	retval = amradio_send_cmd(radio, AMRADIO_SET_FREQ, 0, buf, 3, false);
+	if (retval)
+		return retval;
+	radio->curfreq = freq;
+	msleep(40);
+	return 0;
 }
 
-static int amradio_set_stereo(struct amradio_device *radio, char argument)
+static int amradio_set_stereo(struct amradio_device *radio, bool stereo)
 {
-	int retval;
-	int size;
-
-	radio->buffer[0] = 0x00;
-	radio->buffer[1] = 0x55;
-	radio->buffer[2] = 0xaa;
-	radio->buffer[3] = 0x00;
-	radio->buffer[4] = AMRADIO_SET_MONO;
-	radio->buffer[5] = argument;
-	radio->buffer[6] = 0x00;
-	radio->buffer[7] = 0x00;
+	int ret = amradio_send_cmd(radio,
+			AMRADIO_SET_MONO, !stereo, NULL, 0, false);
 
-	retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
-		(void *) (radio->buffer), BUFFER_LENGTH, &size, USB_TIMEOUT);
-
-	if (retval < 0 || size != BUFFER_LENGTH) {
-		amradio_dev_warn(&radio->vdev.dev, "set stereo failed\n");
-		return retval < 0 ? retval : -EIO;
-	}
-
-	radio->stereo = (argument == WANT_STEREO);
-	return 0;
+	if (!ret)
+		radio->stereo = stereo;
+	return ret;
 }
 
 static int amradio_get_stat(struct amradio_device *radio, bool *is_stereo, u32 *signal)
 {
-	int retval;
-	int size;
-
-	radio->buffer[0] = 0x00;
-	radio->buffer[1] = 0x55;
-	radio->buffer[2] = 0xaa;
-	radio->buffer[3] = 0x00;
-	radio->buffer[4] = AMRADIO_GET_SIGNAL;
-	radio->buffer[5] = 0x00;
-	radio->buffer[6] = 0x00;
-	radio->buffer[7] = 0x08;
-
-	retval = usb_bulk_msg(radio->usbdev, usb_sndbulkpipe(radio->usbdev, 0x02),
-		radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
-	if (!retval)
-		retval = usb_bulk_msg(radio->usbdev, usb_rcvbulkpipe(radio->usbdev, 0x81),
-			radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
+	int ret = amradio_send_cmd(radio,
+			AMRADIO_GET_SIGNAL, 0, NULL, 0, true);
 
-	if (retval || size != BUFFER_LENGTH) {
-		amradio_dev_warn(&radio->vdev.dev, "get stat failed\n");
-		return retval;
-	}
+	if (ret)
+		return ret;
 	*is_stereo = radio->buffer[2] >> 7;
 	*signal = (radio->buffer[3] & 0xf0) << 8;
 	return 0;
@@ -276,8 +252,9 @@ static void usb_amradio_disconnect(struct usb_interface *intf)
 	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
 
 	mutex_lock(&radio->lock);
-	usb_set_intfdata(intf, NULL);
 	video_unregister_device(&radio->vdev);
+	amradio_set_mute(radio, true);
+	usb_set_intfdata(intf, NULL);
 	v4l2_device_disconnect(&radio->v4l2_dev);
 	mutex_unlock(&radio->lock);
 	v4l2_device_put(&radio->v4l2_dev);
@@ -292,7 +269,8 @@ static int vidioc_querycap(struct file *file, void *priv,
 	strlcpy(v->driver, "radio-mr800", sizeof(v->driver));
 	strlcpy(v->card, "AverMedia MR 800 USB FM Radio", sizeof(v->card));
 	usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
-	v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER;
+	v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER |
+					V4L2_CAP_HW_FREQ_SEEK;
 	v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
 	return 0;
 }
@@ -350,7 +328,7 @@ static int vidioc_s_frequency(struct file *file, void *priv,
 
 	if (f->tuner != 0)
 		return -EINVAL;
-	return amradio_setfreq(radio, clamp_t(unsigned, f->frequency,
+	return amradio_set_freq(radio, clamp_t(unsigned, f->frequency,
 				FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL));
 }
 
@@ -368,6 +346,59 @@ static int vidioc_g_frequency(struct file *file, void *priv,
 	return 0;
 }
 
+static int vidioc_s_hw_freq_seek(struct file *file, void *priv,
+		struct v4l2_hw_freq_seek *seek)
+{
+	static u8 buf[8] = {
+		0x3d, 0x32, 0x0f, 0x08, 0x3d, 0x32, 0x0f, 0x08
+	};
+	struct amradio_device *radio = video_drvdata(file);
+	unsigned long timeout;
+	int retval;
+
+	if (seek->tuner != 0 || !seek->wrap_around)
+		return -EINVAL;
+
+	retval = amradio_send_cmd(radio,
+			AMRADIO_SET_SEARCH_LVL, 0, buf, 8, false);
+	if (retval)
+		return retval;
+	amradio_set_freq(radio, radio->curfreq);
+	retval = amradio_send_cmd(radio,
+		seek->seek_upward ? AMRADIO_SET_SEARCH_UP : AMRADIO_SET_SEARCH_DOWN,
+		0, NULL, 0, false);
+	if (retval)
+		return retval;
+	timeout = jiffies + msecs_to_jiffies(30000);
+	for (;;) {
+		if (time_after(jiffies, timeout)) {
+			retval = -EAGAIN;
+			break;
+		}
+		if (schedule_timeout_interruptible(msecs_to_jiffies(10))) {
+			retval = -ERESTARTSYS;
+			break;
+		}
+		retval = amradio_send_cmd(radio, AMRADIO_GET_READY_FLAG,
+				0, NULL, 0, true);
+		if (retval)
+			continue;
+		amradio_send_cmd(radio, AMRADIO_GET_FREQ, 0, NULL, 0, true);
+		if (radio->buffer[1] || radio->buffer[2]) {
+			radio->curfreq = (radio->buffer[1] << 8) | radio->buffer[2];
+			radio->curfreq = (radio->curfreq - 0x10) * 200;
+			amradio_send_cmd(radio, AMRADIO_STOP_SEARCH,
+					0, NULL, 0, false);
+			amradio_set_freq(radio, radio->curfreq);
+			retval = 0;
+			break;
+		}
+	}
+	amradio_send_cmd(radio, AMRADIO_STOP_SEARCH, 0, NULL, 0, false);
+	amradio_set_freq(radio, radio->curfreq);
+	return retval;
+}
+
 static int usb_amradio_s_ctrl(struct v4l2_ctrl *ctrl)
 {
 	struct amradio_device *radio =
@@ -375,8 +406,7 @@ static int usb_amradio_s_ctrl(struct v4l2_ctrl *ctrl)
 
 	switch (ctrl->id) {
 	case V4L2_CID_AUDIO_MUTE:
-		return amradio_set_mute(radio,
-				ctrl->val ? AMRADIO_STOP : AMRADIO_START);
+		return amradio_set_mute(radio, ctrl->val);
 	}
 
 	return -EINVAL;
@@ -386,19 +416,19 @@ static int usb_amradio_init(struct amradio_device *radio)
 {
 	int retval;
 
-	retval = amradio_set_mute(radio, AMRADIO_STOP);
+	retval = amradio_set_mute(radio, true);
 	if (retval)
 		goto out_err;
-
-	retval = amradio_set_stereo(radio, WANT_STEREO);
+	retval = amradio_set_stereo(radio, true);
 	if (retval)
 		goto out_err;
-
-	goto out;
+	retval = amradio_set_freq(radio, radio->curfreq);
+	if (retval)
+		goto out_err;
+	return 0;
 
 out_err:
 	amradio_dev_err(&radio->vdev.dev, "initialization failed\n");
-out:
 	return retval;
 }
 
@@ -409,8 +439,8 @@ static int usb_amradio_suspend(struct usb_interface *intf, pm_message_t message)
 
 	mutex_lock(&radio->lock);
 	if (!radio->muted) {
-		amradio_set_mute(radio, AMRADIO_STOP);
-		radio->muted = 0;
+		amradio_set_mute(radio, true);
+		radio->muted = false;
 	}
 	mutex_unlock(&radio->lock);
 
@@ -424,15 +454,11 @@ static int usb_amradio_resume(struct usb_interface *intf)
 	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
 
 	mutex_lock(&radio->lock);
-	if (radio->stereo)
-		amradio_set_stereo(radio, WANT_STEREO);
-	else
-		amradio_set_stereo(radio, WANT_MONO);
-
-	amradio_setfreq(radio, radio->curfreq);
+	amradio_set_stereo(radio, radio->stereo);
+	amradio_set_freq(radio, radio->curfreq);
 
 	if (!radio->muted)
-		amradio_set_mute(radio, AMRADIO_START);
+		amradio_set_mute(radio, false);
 
 	mutex_unlock(&radio->lock);
 
@@ -459,6 +485,7 @@ static const struct v4l2_ioctl_ops usb_amradio_ioctl_ops = {
 	.vidioc_s_tuner     = vidioc_s_tuner,
 	.vidioc_g_frequency = vidioc_g_frequency,
 	.vidioc_s_frequency = vidioc_s_frequency,
+	.vidioc_s_hw_freq_seek = vidioc_s_hw_freq_seek,
 	.vidioc_log_status  = v4l2_ctrl_log_status,
 	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,