cpia2_usb.c

V4l driver for DVB HD

	if(alt < USBIF_ISO_1 || alt > USBIF_ISO_6)
		return -EINVAL;

	if(alt == cam->params.camera_state.stream_mode)
		return 0;

	cpia2_usb_stream_pause(cam);

	configure_transfer_mode(cam, alt);

	cam->params.camera_state.stream_mode = alt;

	/* Reset the camera to prevent image quality degradation */
	cpia2_reset_camera(cam);

	cpia2_usb_stream_resume(cam);

	return ret;
}

/******************************************************************************
 *
 * set_alternate
 *
 *****************************************************************************/
int set_alternate(struct camera_data *cam, unsigned int alt)
{
	int ret = 0;

	if(alt == cam->cur_alt)
		return 0;

	if (cam->cur_alt != USBIF_CMDONLY) {
		DBG("Changing from alt %d to %d\n", cam->cur_alt, USBIF_CMDONLY);
		ret = usb_set_interface(cam->dev, cam->iface, USBIF_CMDONLY);
		if (ret != 0)
			return ret;
	}
	if (alt != USBIF_CMDONLY) {
		DBG("Changing from alt %d to %d\n", USBIF_CMDONLY, alt);
		ret = usb_set_interface(cam->dev, cam->iface, alt);
		if (ret != 0)
			return ret;
	}

	cam->old_alt = cam->cur_alt;
	cam->cur_alt = alt;

	return ret;
}

/******************************************************************************
 *
 * free_sbufs
 *
 * Free all cam->sbuf[]. All non-NULL .data and .urb members that are non-NULL
 * are assumed to be allocated. Non-NULL .urb members are also assumed to be
 * submitted (and must therefore be killed before they are freed).
 *****************************************************************************/
static void free_sbufs(struct camera_data *cam)
{
	int i;

	for (i = 0; i < NUM_SBUF; i++) {
		if(cam->sbuf[i].urb) {
			usb_kill_urb(cam->sbuf[i].urb);
			usb_free_urb(cam->sbuf[i].urb);
			cam->sbuf[i].urb = NULL;
		}
		if(cam->sbuf[i].data) {
			kfree(cam->sbuf[i].data);
			cam->sbuf[i].data = NULL;
		}
	}
}

/*******
* Convenience functions
*******/
/****************************************************************************
 *
 *  write_packet
 *
 ***************************************************************************/
static int write_packet(struct usb_device *udev,
			u8 request, u8 * registers, u16 start, size_t size)
{
	if (!registers || size <= 0)
		return -EINVAL;

	return usb_control_msg(udev,
			       usb_sndctrlpipe(udev, 0),
			       request,
			       USB_TYPE_VENDOR | USB_RECIP_DEVICE,
			       start,	/* value */
			       0,	/* index */
			       registers,	/* buffer */
			       size,
			       HZ);
}

/****************************************************************************
 *
 *  read_packet
 *
 ***************************************************************************/
static int read_packet(struct usb_device *udev,
		       u8 request, u8 * registers, u16 start, size_t size)
{
	if (!registers || size <= 0)
		return -EINVAL;

	return usb_control_msg(udev,
			       usb_rcvctrlpipe(udev, 0),
			       request,
			       USB_DIR_IN|USB_TYPE_VENDOR|USB_RECIP_DEVICE,
			       start,	/* value */
			       0,	/* index */
			       registers,	/* buffer */
			       size,
			       HZ);
}

/******************************************************************************
 *
 *  cpia2_usb_transfer_cmd
 *
 *****************************************************************************/
int cpia2_usb_transfer_cmd(struct camera_data *cam,
			   void *registers,
			   u8 request, u8 start, u8 count, u8 direction)
{
	int err = 0;
	struct usb_device *udev = cam->dev;

	if (!udev) {
		ERR("%s: Internal driver error: udev is NULL\n", __func__);
		return -EINVAL;
	}

	if (!registers) {
		ERR("%s: Internal driver error: register array is NULL\n", __func__);
		return -EINVAL;
	}

	if (direction == TRANSFER_READ) {
		err = read_packet(udev, request, (u8 *)registers, start, count);
		if (err > 0)
			err = 0;
	} else if (direction == TRANSFER_WRITE) {
		err =write_packet(udev, request, (u8 *)registers, start, count);
		if (err < 0) {
			LOG("Control message failed, err val = %d\n", err);
			LOG("Message: request = 0x%0X, start = 0x%0X\n",
			    request, start);
			LOG("Message: count = %d, register[0] = 0x%0X\n",
			    count, ((unsigned char *) registers)[0]);
		} else
			err=0;
	} else {
		LOG("Unexpected first byte of direction: %d\n",
		       direction);
		return -EINVAL;
	}

	if(err != 0)
		LOG("Unexpected error: %d\n", err);
	return err;
}


/******************************************************************************
 *
 *  submit_urbs
 *
 *****************************************************************************/
static int submit_urbs(struct camera_data *cam)
{
	struct urb *urb;
	int fx, err, i;

	for(i=0; i<NUM_SBUF; ++i) {
		if (cam->sbuf[i].data)
			continue;
		cam->sbuf[i].data =
		    kmalloc(FRAMES_PER_DESC * FRAME_SIZE_PER_DESC, GFP_KERNEL);
		if (!cam->sbuf[i].data) {
			return -ENOMEM;
		}
	}

	/* We double buffer the Isoc lists, and also know the polling
	 * interval is every frame (1 == (1 << (bInterval -1))).
	 */
	for(i=0; i<NUM_SBUF; ++i) {
		if(cam->sbuf[i].urb) {
			continue;
		}
		urb = usb_alloc_urb(FRAMES_PER_DESC, GFP_KERNEL);
		if (!urb) {
			return -ENOMEM;
		}

		cam->sbuf[i].urb = urb;
		urb->dev = cam->dev;
		urb->context = cam;
		urb->pipe = usb_rcvisocpipe(cam->dev, 1 /*ISOC endpoint*/);
		urb->transfer_flags = URB_ISO_ASAP;
		urb->transfer_buffer = cam->sbuf[i].data;
		urb->complete = cpia2_usb_complete;
		urb->number_of_packets = FRAMES_PER_DESC;
		urb->interval = 1;
		urb->transfer_buffer_length =
			FRAME_SIZE_PER_DESC * FRAMES_PER_DESC;

		for (fx = 0; fx < FRAMES_PER_DESC; fx++) {
			urb->iso_frame_desc[fx].offset =
				FRAME_SIZE_PER_DESC * fx;
			urb->iso_frame_desc[fx].length = FRAME_SIZE_PER_DESC;
		}
	}


	/* Queue the ISO urbs, and resubmit in the completion handler */
	for(i=0; i<NUM_SBUF; ++i) {
		err = usb_submit_urb(cam->sbuf[i].urb, GFP_KERNEL);
		if (err) {
			ERR("usb_submit_urb[%d]() = %d\n", i, err);
			return err;
		}
	}

	return 0;
}

/******************************************************************************
 *
 *  cpia2_usb_stream_start
 *
 *****************************************************************************/
int cpia2_usb_stream_start(struct camera_data *cam, unsigned int alternate)
{
	int ret;
	int old_alt;

	if(cam->streaming)
		return 0;

	if (cam->flush) {
		int i;
		DBG("Flushing buffers\n");
		for(i=0; i<cam->num_frames; ++i) {
			cam->buffers[i].status = FRAME_EMPTY;
			cam->buffers[i].length = 0;
		}
		cam->curbuff = &cam->buffers[0];
		cam->workbuff = cam->curbuff->next;
		cam->flush = false;
	}

	old_alt = cam->params.camera_state.stream_mode;
	cam->params.camera_state.stream_mode = 0;
	ret = cpia2_usb_change_streaming_alternate(cam, alternate);
	if (ret < 0) {
		int ret2;
		ERR("cpia2_usb_change_streaming_alternate() = %d!\n", ret);
		cam->params.camera_state.stream_mode = old_alt;
		ret2 = set_alternate(cam, USBIF_CMDONLY);
		if (ret2 < 0) {
			ERR("cpia2_usb_change_streaming_alternate(%d) =%d has already "
			    "failed. Then tried to call "
			    "set_alternate(USBIF_CMDONLY) = %d.\n",
			    alternate, ret, ret2);
		}
	} else {
		cam->frame_count = 0;
		cam->streaming = 1;
		ret = cpia2_usb_stream_resume(cam);
	}
	return ret;
}

/******************************************************************************
 *
 *  cpia2_usb_stream_pause
 *
 *****************************************************************************/
int cpia2_usb_stream_pause(struct camera_data *cam)
{
	int ret = 0;
	if(cam->streaming) {
		ret = set_alternate(cam, USBIF_CMDONLY);
		free_sbufs(cam);
	}
	return ret;
}

/******************************************************************************
 *
 *  cpia2_usb_stream_resume
 *
 *****************************************************************************/
int cpia2_usb_stream_resume(struct camera_data *cam)
{
	int ret = 0;
	if(cam->streaming) {
		cam->first_image_seen = 0;
		ret = set_alternate(cam, cam->params.camera_state.stream_mode);
		if(ret == 0) {
			ret = submit_urbs(cam);
		}
	}
	return ret;
}

/******************************************************************************
 *
 *  cpia2_usb_stream_stop
 *
 *****************************************************************************/
int cpia2_usb_stream_stop(struct camera_data *cam)
{
	int ret;
	ret = cpia2_usb_stream_pause(cam);
	cam->streaming = 0;
	configure_transfer_mode(cam, 0);
	return ret;
}

/******************************************************************************
 *
 *  cpia2_usb_probe
 *
 *  Probe and initialize.
 *****************************************************************************/
static int cpia2_usb_probe(struct usb_interface *intf,
			   const struct usb_device_id *id)
{
	struct usb_device *udev = interface_to_usbdev(intf);
	struct usb_interface_descriptor *interface;
	struct camera_data *cam;
	int ret;

	/* A multi-config CPiA2 camera? */
	if (udev->descriptor.bNumConfigurations != 1)
		return -ENODEV;
	interface = &intf->cur_altsetting->desc;

	/* If we get to this point, we found a CPiA2 camera */
	LOG("CPiA2 USB camera found\n");

	if((cam = cpia2_init_camera_struct()) == NULL)
		return -ENOMEM;

	cam->dev = udev;
	cam->iface = interface->bInterfaceNumber;

	ret = set_alternate(cam, USBIF_CMDONLY);
	if (ret < 0) {
		ERR("%s: usb_set_interface error (ret = %d)\n", __func__, ret);
		kfree(cam);
		return ret;
	}

	if ((ret = cpia2_register_camera(cam)) < 0) {
		ERR("%s: Failed to register cpia2 camera (ret = %d)\n", __func__, ret);
		kfree(cam);
		return ret;
	}


	if((ret = cpia2_init_camera(cam)) < 0) {
		ERR("%s: failed to initialize cpia2 camera (ret = %d)\n", __func__, ret);
		cpia2_unregister_camera(cam);
		kfree(cam);
		return ret;
	}
	LOG("  CPiA Version: %d.%02d (%d.%d)\n",
	       cam->params.version.firmware_revision_hi,
	       cam->params.version.firmware_revision_lo,
	       cam->params.version.asic_id,
	       cam->params.version.asic_rev);
	LOG("  CPiA PnP-ID: %04x:%04x:%04x\n",
	       cam->params.pnp_id.vendor,
	       cam->params.pnp_id.product,
	       cam->params.pnp_id.device_revision);
	LOG("  SensorID: %d.(version %d)\n",
	       cam->params.version.sensor_flags,
	       cam->params.version.sensor_rev);

	usb_set_intfdata(intf, cam);

	return 0;
}

/******************************************************************************
 *
 *  cpia2_disconnect
 *
 *****************************************************************************/
static void cpia2_usb_disconnect(struct usb_interface *intf)
{
	struct camera_data *cam = usb_get_intfdata(intf);
	usb_set_intfdata(intf, NULL);
	cam->present = 0;

	DBG("Stopping stream\n");
	cpia2_usb_stream_stop(cam);

	DBG("Unregistering camera\n");
	cpia2_unregister_camera(cam);

	if(cam->buffers) {
		DBG("Wakeup waiting processes\n");
		cam->curbuff->status = FRAME_READY;
		cam->curbuff->length = 0;
		if (waitqueue_active(&cam->wq_stream))
			wake_up_interruptible(&cam->wq_stream);
	}

	DBG("Releasing interface\n");
	usb_driver_release_interface(&cpia2_driver, intf);

	if (cam->open_count == 0) {
		DBG("Freeing camera structure\n");
		kfree(cam);
	}

	LOG("CPiA2 camera disconnected.\n");
}


/******************************************************************************
 *
 *  usb_cpia2_init
 *
 *****************************************************************************/
int cpia2_usb_init(void)
{
	return usb_register(&cpia2_driver);
}

/******************************************************************************
 *
 *  usb_cpia_cleanup
 *
 *****************************************************************************/
void cpia2_usb_cleanup(void)
{
	schedule_timeout(2 * HZ);
	usb_deregister(&cpia2_driver);
}