Add UVC driver and test/example

2 files changed, 669 insertions, 22 deletions

diff --git a/os/hal/src/hal_usbh.c b/os/hal/src/hal_usbh.c
index 457abba..d242086 100644
--- a/os/hal/src/hal_usbh.c
+++ b/os/hal/src/hal_usbh.c
@@ -28,6 +28,7 @@
 #include "usbh/dev/ftdi.h"
 #include "usbh/dev/msd.h"
 #include "usbh/dev/hid.h"
+#include "usbh/dev/uvc.h"
 
 #if USBH_DEBUG_ENABLE_TRACE
 #define udbgf(f, ...)  usbDbgPrintf(f, ##__VA_ARGS__)
@@ -125,6 +126,9 @@ void usbhInit(void) {
 #if HAL_USBH_USE_HID
 	usbhhidInit();
 #endif
+#if HAL_USBH_USE_UVC
+	usbhuvcInit();
+#endif
 #if HAL_USBH_USE_HUB
 	usbhhubInit();
 #endif
@@ -421,7 +425,8 @@ usbh_urbstatus_t usbhControlRequestExtended(usbh_device_t *dev,
 		uint32_t *actual_len,
 		systime_t timeout) {
 
-	_check_dev(dev);
+	if (!dev) return USBH_URBSTATUS_DISCONNECTED;
+
 	osalDbgCheck(req != NULL);
 
 	usbh_urb_t urb;
@@ -1310,6 +1315,9 @@ static const usbh_classdriverinfo_t *usbh_classdrivers_lookup[] = {
 #if HAL_USBH_USE_HID
 	&usbhhidClassDriverInfo,
 #endif
+#if HAL_USBH_USE_UVC
+	&usbhuvcClassDriverInfo,
+#endif
 #if HAL_USBH_USE_HUB
 	&usbhhubClassDriverInfo,
 #endif
@@ -1341,7 +1349,7 @@ static bool _classdriver_load(usbh_device_t *dev, uint8_t class,
 #if HAL_USBH_USE_IAD
 			/* special case: */
 			if (info == &usbhiadClassDriverInfo)
-				return HAL_SUCCESS;
+				goto success; //return HAL_SUCCESS;
 #endif
 
 			if (drv != NULL)
diff --git a/os/hal/src/usbh/hal_usbh_uvc.c b/os/hal/src/usbh/hal_usbh_uvc.c
index 025fbee..72c15c0 100644
--- a/os/hal/src/usbh/hal_usbh_uvc.c
+++ b/os/hal/src/usbh/hal_usbh_uvc.c
@@ -1,22 +1,17 @@
 /*
-    ChibiOS - Copyright (C) 2006..2017 Giovanni Di Sirio
-              Copyright (C) 2015..2017 Diego Ismirlian, (dismirlian (at) google's mail)
-
-    Licensed under the Apache License, Version 2.0 (the "License");
-    you may not use this file except in compliance with the License.
-    You may obtain a copy of the License at
-
-        http://www.apache.org/licenses/LICENSE-2.0
-
-    Unless required by applicable law or agreed to in writing, software
-    distributed under the License is distributed on an "AS IS" BASIS,
-    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-    See the License for the specific language governing permissions and
-    limitations under the License.
-*/
+ * usbh_uvc.c
+ *
+ *  Created on: 14 de set. de 2015
+ *      Author: Diego Ismirlian (dismirlian (at) google's mail (dot) com)
+ *
+ *  License:
+ *
+ *  This file is free for non-commercial use until the company I work for decides what to do.
+ *  If in doubt, please contact me.
+ *
+ */
 
 #include "hal.h"
-#include "hal_usbh.h"
 
 #if HAL_USBH_USE_UVC
 
@@ -28,6 +23,10 @@
 #error "USBHUVC needs HAL_USBH_USE_IAD"
 #endif
 
+#include "usbh/dev/uvc.h"
+#include "usbh/internal.h"
+#include <string.h>
+
 #if USBHUVC_DEBUG_ENABLE_TRACE
 #define udbgf(f, ...)  usbDbgPrintf(f, ##__VA_ARGS__)
 #define udbg(f, ...)  usbDbgPuts(f, ##__VA_ARGS__)
@@ -61,6 +60,9 @@
 #endif
 
 
+USBHUVCDriver USBHUVCD[HAL_USBHUVC_MAX_INSTANCES];
+
+
 static usbh_baseclassdriver_t *uvc_load(usbh_device_t *dev,
 		const uint8_t *descriptor, uint16_t rem);
 static void uvc_unload(usbh_baseclassdriver_t *drv);
@@ -73,16 +75,653 @@ const usbh_classdriverinfo_t usbhuvcClassDriverInfo = {
 	0x0e, 0x03, 0x00, "UVC", &class_driver_vmt
 };
 
+static bool _request(USBHUVCDriver *uvcdp,
+		uint8_t bRequest, uint8_t entity, uint8_t control,
+		uint16_t wLength, uint8_t *data, uint8_t interf) {
+
+	usbh_urbstatus_t res;
+
+	if (bRequest & 0x80) {
+		res = usbhControlRequest(uvcdp->dev,
+				USBH_REQTYPE_CLASSIN(USBH_REQTYPE_RECIP_INTERFACE),
+				bRequest,
+				((control) << 8),
+				(interf) | ((entity) << 8),
+				wLength, data);
+	} else {
+		res = usbhControlRequest(uvcdp->dev,
+				USBH_REQTYPE_CLASSOUT(USBH_REQTYPE_RECIP_INTERFACE),
+				bRequest,
+				((control) << 8),
+				(interf) | ((entity) << 8),
+				wLength, data);
+	}
+
+	if (res != USBH_URBSTATUS_OK)
+		return HAL_FAILED;
+
+	 return HAL_SUCCESS;
+}
+
+bool usbhuvcVCRequest(USBHUVCDriver *uvcdp,
+		uint8_t bRequest, uint8_t entity, uint8_t control,
+		uint16_t wLength, uint8_t *data) {
+	return _request(uvcdp, bRequest, entity, control, wLength, data, if_get(&uvcdp->ivc)->bInterfaceNumber);
+}
+
+bool usbhuvcVSRequest(USBHUVCDriver *uvcdp,
+		uint8_t bRequest, uint8_t control,
+		uint16_t wLength, uint8_t *data) {
+
+	return _request(uvcdp, bRequest, 0, control, wLength, data, if_get(&uvcdp->ivs)->bInterfaceNumber);
+}
+
+static bool _set_vs_alternate(USBHUVCDriver *uvcdp, uint16_t min_ep_size) {
+
+	if (min_ep_size == 0) {
+		uinfo("Selecting Alternate setting 0");
+		return usbhStdReqSetInterface(uvcdp->dev, if_get(&uvcdp->ivs)->bInterfaceNumber, 0);
+	}
+
+	if_iterator_t iif = uvcdp->ivs;
+	generic_iterator_t iep;
+	const usbh_endpoint_descriptor_t *ep = NULL;
+	uint8_t alt = 0;
+	uint16_t sz = 0xffff;
+
+	uinfof("Searching alternate setting with min_ep_size=%d", min_ep_size);
+
+	for (; iif.valid; if_iter_next(&iif)) {
+		const usbh_interface_descriptor_t *const ifdesc = if_get(&iif);
+
+		if ((ifdesc->bInterfaceClass != UVC_CC_VIDEO)
+				|| (ifdesc->bInterfaceSubClass != UVC_SC_VIDEOSTREAMING))
+			continue;
+
+		uinfof("\tScanning alternate setting=%d", ifdesc->bAlternateSetting);
+
+		if (ifdesc->bNumEndpoints == 0)
+			continue;
+
+		for (ep_iter_init(&iep, &iif); iep.valid; ep_iter_next(&iep)) {
+			const usbh_endpoint_descriptor_t *const epdesc = ep_get(&iep);
+			if (((epdesc->bmAttributes & 0x03) == USBH_EPTYPE_ISO)
+					&& ((epdesc->bEndpointAddress & 0x80) ==  USBH_EPDIR_IN)) {
+
+				uinfof("\t  Endpoint wMaxPacketSize = %d", epdesc->wMaxPacketSize);
+
+				if (epdesc->wMaxPacketSize >= min_ep_size) {
+					if (epdesc->wMaxPacketSize < sz) {
+						uinfo("\t    Found new optimal alternate setting");
+						sz = epdesc->wMaxPacketSize;
+						alt = ifdesc->bAlternateSetting;
+						ep = epdesc;
+					}
+				}
+			}
+		}
+	}
+
+	if (ep && alt) {
+		uinfof("\tSelecting Alternate setting %d", alt);
+		if (usbhStdReqSetInterface(uvcdp->dev, if_get(&uvcdp->ivs)->bInterfaceNumber, alt) == HAL_SUCCESS) {
+			usbhEPObjectInit(&uvcdp->ep_iso, uvcdp->dev, ep);
+			usbhEPSetName(&uvcdp->ep_iso, "UVC[ISO ]");
+			return HAL_SUCCESS;
+		}
+	}
+
+	return HAL_FAILED;
+}
+
+#if	USBH_DEBUG_ENABLE && USBHUVC_DEBUG_ENABLE_INFO
+void usbhuvcPrintProbeCommit(const usbh_uvc_ctrl_vs_probecommit_data_t *pc) {
+
+	//uinfof("UVC: probe/commit data:");
+	uinfof("\tbmHint=%04x", pc->bmHint);
+	uinfof("\tbFormatIndex=%d, bFrameIndex=%d, dwFrameInterval=%u",
+			pc->bFormatIndex, pc->bFrameIndex, pc->dwFrameInterval);
+	uinfof("\twKeyFrameRate=%d, wPFrameRate=%d, wCompQuality=%u, wCompWindowSize=%u",
+			pc->wKeyFrameRate, pc->wPFrameRate, pc->wCompQuality, pc->wCompWindowSize);
+	uinfof("\twDelay=%d", pc->wDelay);
+	uinfof("\tdwMaxVideoFrameSize=%u", pc->dwMaxVideoFrameSize);
+	uinfof("\tdwMaxPayloadTransferSize=%u", pc->dwMaxPayloadTransferSize);
+/*	uinfof("\tdwClockFrequency=%u", pc->dwClockFrequency);
+	uinfof("\tbmFramingInfo=%02x", pc->bmFramingInfo);
+	uinfof("\tbPreferedVersion=%d, bMinVersion=%d, bMaxVersion=%d",
+			pc->bPreferedVersion, pc->bMinVersion, pc->bMaxVersion); */
+}
+#endif
+
+static void _post(USBHUVCDriver *uvcdp, usbh_urb_t *urb, memory_pool_t *mp, uint16_t type) {
+	usbhuvc_message_base_t *const msg = (usbhuvc_message_base_t *)urb->buff - 1;
+	msg->timestamp = osalOsGetSystemTimeX();
+
+	usbhuvc_message_base_t *const new_msg = (usbhuvc_message_base_t *)chPoolAllocI(mp);
+	if (new_msg != NULL) {
+		/* allocated the new buffer, now try to post the message to the mailbox */
+		if (chMBPostI(&uvcdp->mb, (msg_t)msg) == MSG_OK) {
+			/* everything OK, complete the missing fields */
+			msg->type = type;
+			msg->length = urb->actualLength;
+
+			/* change the URB's buffer to the newly allocated one */
+			urb->buff = (uint8_t *)(new_msg + 1);
+		} else {
+			/* couldn't post the message, free the newly allocated buffer */
+			uerr("UVC: error, mailbox overrun");
+			chPoolFreeI(&uvcdp->mp_status, new_msg);
+		}
+	} else {
+		uerrf("UVC: error, %s pool overrun", mp == &uvcdp->mp_data ? "data" : "status");
+	}
+}
+
+static void _cb_int(usbh_urb_t *urb) {
+	USBHUVCDriver *uvcdp = (USBHUVCDriver *)urb->userData;
+
+	switch (urb->status) {
+	case USBH_URBSTATUS_OK:
+		if (urb->actualLength >= 2) {
+			_post(uvcdp, urb, &uvcdp->mp_status, USBHUVC_MESSAGETYPE_STATUS);
+		} else {
+			uerrf("UVC: INT IN, actualLength=%d", urb->actualLength);
+		}
+		break;
+	case USBH_URBSTATUS_TIMEOUT:	/* the device NAKed */
+		udbg("UVC: INT IN no info");
+		break;
+	case USBH_URBSTATUS_DISCONNECTED:
+	case USBH_URBSTATUS_CANCELLED:
+		uwarn("UVC: INT IN status = DISCONNECTED/CANCELLED, aborting");
+		return;
+	default:
+		uerrf("UVC: INT IN error, unexpected status = %d", urb->status);
+		break;
+	}
+
+	usbhURBObjectResetI(urb);
+	usbhURBSubmitI(urb);
+}
+
+static void _cb_iso(usbh_urb_t *urb) {
+	USBHUVCDriver *uvcdp = (USBHUVCDriver *)urb->userData;
+
+	if ((urb->status == USBH_URBSTATUS_DISCONNECTED)
+			|| (urb->status == USBH_URBSTATUS_CANCELLED)) {
+		uwarn("UVC: ISO IN status = DISCONNECTED/CANCELLED, aborting");
+		return;
+	}
+
+	if (urb->status != USBH_URBSTATUS_OK) {
+		uerrf("UVC: ISO IN error, unexpected status = %d", urb->status);
+	} else if (urb->actualLength >= 2) {
+		const uint8_t *const buff = (const uint8_t *)urb->buff;
+		if (buff[0] < 2) {
+			uerrf("UVC: ISO IN, bHeaderLength=%d", buff[0]);
+		} else if (buff[0] > urb->actualLength) {
+			uerrf("UVC: ISO IN, bHeaderLength=%d > actualLength=%d", buff[0], urb->actualLength);
+		} else {
+			udbgf("UVC: ISO IN len=%d, hdr=%d, FID=%d, EOF=%d, ERR=%d, EOH=%d",
+						urb->actualLength,
+						buff[0],
+						buff[1] & UVC_HDR_FID,
+						buff[1] & UVC_HDR_EOF,
+						buff[1] & UVC_HDR_ERR,
+						buff[1] & UVC_HDR_EOH);
+
+			if ((urb->actualLength > buff[0])
+					|| (buff[1] & (UVC_HDR_EOF | UVC_HDR_ERR))) {
+				_post(uvcdp, urb, &uvcdp->mp_data, USBHUVC_MESSAGETYPE_DATA);
+			} else {
+				udbgf("UVC: ISO IN skip: len=%d, hdr=%d, FID=%d, EOF=%d, ERR=%d, EOH=%d",
+						urb->actualLength,
+						buff[0],
+						buff[1] & UVC_HDR_FID,
+						buff[1] & UVC_HDR_EOF,
+						buff[1] & UVC_HDR_ERR,
+						buff[1] & UVC_HDR_EOH);
+			}
+		}
+	} else if (urb->actualLength > 0) {
+		uerrf("UVC: ISO IN, actualLength=%d", urb->actualLength);
+	}
+
+	usbhURBObjectResetI(urb);
+	usbhURBSubmitI(urb);
+}
+
+
+bool usbhuvcStreamStart(USBHUVCDriver *uvcdp, uint16_t min_ep_sz) {
+	bool ret = HAL_FAILED;
+	osalSysLock();
+	osalDbgCheck(uvcdp && (uvcdp->state != USBHUVC_STATE_UNINITIALIZED) &&
+					(uvcdp->state != USBHUVC_STATE_BUSY));
+	if (uvcdp->state == USBHUVC_STATE_STREAMING) {
+		osalSysUnlock();
+		return HAL_SUCCESS;
+	}
+	if (uvcdp->state != USBHUVC_STATE_READY) {
+		osalSysUnlock();
+		return HAL_FAILED;
+	}
+	uvcdp->state = USBHUVC_STATE_BUSY;
+	osalSysUnlock();
+
+	//set the alternate setting
+	if (_set_vs_alternate(uvcdp, min_ep_sz) != HAL_SUCCESS)
+		goto exit;
+
+	//reserve working RAM
+	uint32_t datapackets;
+	uint32_t data_sz = (uvcdp->ep_iso.wMaxPacketSize + sizeof(usbhuvc_message_data_t) + 3) & ~3;
+
+	datapackets = HAL_USBHUVC_WORK_RAM_SIZE / data_sz;
+	if (datapackets == 0) {
+		uerr("Not enough work RAM");
+		goto failed;
+	}
+
+	uint32_t workramsz = datapackets * data_sz;
+	uinfof("Reserving %u bytes of RAM (%d data packets of %d bytes)", workramsz, datapackets, data_sz);
+	if (datapackets > (HAL_USBHUVC_MAX_MAILBOX_SZ - HAL_USBHUVC_STATUS_PACKETS_COUNT)) {
+		uwarn("Mailbox may overflow, use a larger HAL_USBHUVC_MAX_MAILBOX_SZ. UVC will under-utilize the assigned work RAM.");
+	}
+	chMBResumeX(&uvcdp->mb);
+
+	uvcdp->mp_data_buffer = chHeapAlloc(NULL, workramsz);
+	if (uvcdp->mp_data_buffer == NULL) {
+		uerr("Couldn't reserve RAM");
+		goto failed;
+	}
+
+	//initialize the mempool
+	const uint8_t *elem = (const uint8_t *)uvcdp->mp_data_buffer;
+	chPoolObjectInit(&uvcdp->mp_data, data_sz, NULL);
+	while (datapackets--) {
+		chPoolFree(&uvcdp->mp_data, (void *)elem);
+		elem += data_sz;
+	}
+
+	//open the endpoint
+	usbhEPOpen(&uvcdp->ep_iso);
+
+	//allocate 1 buffer and submit the first transfer
+	usbhuvc_message_data_t *const msg = (usbhuvc_message_data_t *)chPoolAlloc(&uvcdp->mp_data);
+	osalDbgCheck(msg);
+	usbhURBObjectInit(&uvcdp->urb_iso, &uvcdp->ep_iso, _cb_iso, uvcdp, msg->data, uvcdp->ep_iso.wMaxPacketSize);
+	osalSysLock();
+	usbhURBSubmitI(&uvcdp->urb_iso);
+	osalOsRescheduleS();
+	osalSysUnlock();
+
+	ret = HAL_SUCCESS;
+	goto exit;
+
+failed:
+	_set_vs_alternate(uvcdp, 0);
+	if (uvcdp->mp_data_buffer)
+		chHeapFree(uvcdp->mp_data_buffer);
+
+exit:
+	osalSysLock();
+	if (ret == HAL_SUCCESS)
+		uvcdp->state = USBHUVC_STATE_STREAMING;
+	else
+		uvcdp->state = USBHUVC_STATE_READY;
+	osalSysUnlock();
+	return ret;
+}
+
+bool usbhuvcStreamStop(USBHUVCDriver *uvcdp) {
+	osalSysLock();
+	osalDbgCheck(uvcdp && (uvcdp->state != USBHUVC_STATE_UNINITIALIZED) &&
+					(uvcdp->state != USBHUVC_STATE_BUSY));
+	if (uvcdp->state != USBHUVC_STATE_STREAMING) {
+		osalSysUnlock();
+		return HAL_SUCCESS;
+	}
+	uvcdp->state = USBHUVC_STATE_BUSY;
+
+	//close the ISO endpoint
+	usbhEPCloseS(&uvcdp->ep_iso);
+
+	//purge the mailbox
+	chMBResetI(&uvcdp->mb);		//TODO: the status messages are lost!!
+	chMtxLockS(&uvcdp->mtx);
+	osalSysUnlock();
+
+	//free the working memory
+	chHeapFree(uvcdp->mp_data_buffer);
+	uvcdp->mp_data_buffer = 0;
+
+	//set alternate setting to 0
+	_set_vs_alternate(uvcdp, 0);
+
+	osalSysLock();
+	uvcdp->state = USBHUVC_STATE_READY;
+	chMtxUnlockS(&uvcdp->mtx);
+	osalSysUnlock();
+	return HAL_SUCCESS;
+}
+
+bool usbhuvcFindVSDescriptor(USBHUVCDriver *uvcdp,
+		generic_iterator_t *ics,
+		uint8_t bDescriptorSubtype,
+		bool start) {
+
+	if (start)
+		cs_iter_init(ics, (generic_iterator_t *)&uvcdp->ivs);
+	else
+		cs_iter_next(ics);
+
+	for (; ics->valid; cs_iter_next(ics)) {
+		if (ics->curr[1] != UVC_CS_INTERFACE)
+			break;
+		if (ics->curr[2] == bDescriptorSubtype)
+			return HAL_SUCCESS;
+		if (!start)
+			break;
+	}
+	return HAL_FAILED;
+}
+
+void usbhuvcResetPC(USBHUVCDriver *uvcdp) {
+	memset(&uvcdp->pc, 0, sizeof(uvcdp->pc));
+}
+
+bool usbhuvcProbe(USBHUVCDriver *uvcdp) {
+//	memset(&uvcdp->pc_min, 0, sizeof(uvcdp->pc_min));
+//	memset(&uvcdp->pc_max, 0, sizeof(uvcdp->pc_max));
+
+	if (usbhuvcVSRequest(uvcdp, UVC_SET_CUR, UVC_CTRL_VS_PROBE_CONTROL, sizeof(uvcdp->pc), (uint8_t *)&uvcdp->pc) != HAL_SUCCESS)
+		return HAL_FAILED;
+	if (usbhuvcVSRequest(uvcdp, UVC_GET_CUR, UVC_CTRL_VS_PROBE_CONTROL, sizeof(uvcdp->pc), (uint8_t *)&uvcdp->pc) != HAL_SUCCESS)
+		return HAL_FAILED;
+	if (usbhuvcVSRequest(uvcdp, UVC_GET_MAX, UVC_CTRL_VS_PROBE_CONTROL, sizeof(uvcdp->pc_max), (uint8_t *)&uvcdp->pc_max) != HAL_SUCCESS)
+		return HAL_FAILED;
+	if (usbhuvcVSRequest(uvcdp, UVC_GET_MIN, UVC_CTRL_VS_PROBE_CONTROL, sizeof(uvcdp->pc_min), (uint8_t *)&uvcdp->pc_min) != HAL_SUCCESS)
+		return HAL_FAILED;
+	return HAL_SUCCESS;
+}
+
+bool usbhuvcCommit(USBHUVCDriver *uvcdp) {
+	if (usbhuvcVSRequest(uvcdp, UVC_SET_CUR, UVC_CTRL_VS_COMMIT_CONTROL, sizeof(uvcdp->pc), (uint8_t *)&uvcdp->pc) != HAL_SUCCESS)
+		return HAL_FAILED;
+
+	osalSysLock();
+	if (uvcdp->state == USBHUVC_STATE_ACTIVE)
+		uvcdp->state = USBHUVC_STATE_READY;
+	osalSysUnlock();
+	return HAL_SUCCESS;
+}
+
+uint32_t usbhuvcEstimateRequiredEPSize(USBHUVCDriver *uvcdp, const uint8_t *formatdesc,
+		const uint8_t *framedesc, uint32_t dwFrameInterval) {
+
+	osalDbgCheck(framedesc);
+	osalDbgCheck(framedesc[0] > 3);
+	osalDbgCheck(framedesc[1] == UVC_CS_INTERFACE);
+	osalDbgCheck(formatdesc);
+	osalDbgCheck(formatdesc[0] > 3);
+	osalDbgCheck(formatdesc[1] == UVC_CS_INTERFACE);
+
+	uint16_t w, h, div, mul;
+	uint8_t bpp;
+
+	switch (framedesc[2]) {
+	case UVC_VS_FRAME_MJPEG: {
+		const usbh_uvc_frame_mjpeg_t *frame = (const usbh_uvc_frame_mjpeg_t *)framedesc;
+		//const usbh_uvc_format_mjpeg_t *fmt = (const usbh_uvc_format_mjpeg_t *)formatdesc;
+		w = frame->wWidth;
+		h = frame->wHeight;
+		bpp = 16;	//TODO: check this!!
+		mul = 1;
+		div = 5;	//TODO: check this estimate
+	}	break;
+	case UVC_VS_FRAME_UNCOMPRESSED: {
+		const usbh_uvc_frame_uncompressed_t *frame = (const usbh_uvc_frame_uncompressed_t *)framedesc;
+		const usbh_uvc_format_uncompressed *fmt = (const usbh_uvc_format_uncompressed *)formatdesc;
+		w = frame->wWidth;
+		h = frame->wHeight;
+		bpp = fmt->bBitsPerPixel;
+		mul = div = 1;
+	}	break;
+	default:
+		uwarn("Unsupported format");
+		return 0xffffffff;
+	}
+
+	uint32_t sz = w * h / 8 * bpp;
+	sz *= 10000000UL / dwFrameInterval;
+	sz /= 1000;
+
+	if (uvcdp->dev->speed == USBH_DEVSPEED_HIGH)
+		div *= 8;
+
+	return (sz * mul) / div + 12;
+}
+
+void usbhuvcObjectInit(USBHUVCDriver *uvcdp) {
+	osalDbgCheck(uvcdp != NULL);
+	memset(uvcdp, 0, sizeof(*uvcdp));
+	uvcdp->info = &usbhuvcClassDriverInfo;
+	chMBObjectInit(&uvcdp->mb, uvcdp->mb_buff, HAL_USBHUVC_MAX_MAILBOX_SZ);
+	chMtxObjectInit(&uvcdp->mtx);
+	uvcdp->state = USBHUVC_STATE_STOP;
+}
+
 
 static usbh_baseclassdriver_t *uvc_load(usbh_device_t *dev, const uint8_t *descriptor, uint16_t rem) {
-	(void)dev;
-	(void)descriptor;
-	(void)rem;
+
+	USBHUVCDriver *uvcdp;
+	uint8_t i;
+
+	if (descriptor[1] != USBH_DT_INTERFACE_ASSOCIATION)
+		return NULL;
+
+	/* alloc driver */
+	for (i = 0; i < HAL_USBHUVC_MAX_INSTANCES; i++) {
+		if (USBHUVCD[i].dev == NULL) {
+			uvcdp = &USBHUVCD[i];
+			goto alloc_ok;
+		}
+	}
+
+	uwarn("Can't alloc UVC driver");
+
+	/* can't alloc */
 	return NULL;
+
+alloc_ok:
+	/* initialize the driver's variables */
+	uvcdp->ivc.curr = uvcdp->ivs.curr = NULL;
+
+	usbhEPSetName(&dev->ctrl, "UVC[CTRL]");
+
+	const usbh_ia_descriptor_t *iad = (const usbh_ia_descriptor_t *)descriptor;
+	if_iterator_t iif;
+	generic_iterator_t ics;
+	generic_iterator_t iep;
+
+	iif.iad = iad;
+	iif.curr = descriptor;
+	iif.rem = rem;
+
+	for (if_iter_next(&iif); iif.valid; if_iter_next(&iif)) {
+		if (iif.iad != iad) break;
+
+		const usbh_interface_descriptor_t *const ifdesc = if_get(&iif);
+		if (ifdesc->bInterfaceClass != UVC_CC_VIDEO) {
+			uwarnf("Skipping Interface %d (class != UVC_CC_VIDEO)",
+					ifdesc->bInterfaceNumber);
+			continue;
+		}
+
+		uinfof("Interface %d, Alt=%d, Class=UVC_CC_VIDEO, Subclass=%02x",
+				ifdesc->bInterfaceNumber,
+				ifdesc->bAlternateSetting,
+				ifdesc->bInterfaceSubClass);
+
+		switch (ifdesc->bInterfaceSubClass) {
+		case UVC_SC_VIDEOCONTROL:
+			if (uvcdp->ivc.curr == NULL) {
+				uvcdp->ivc = iif;
+			}
+			for (cs_iter_init(&ics, (generic_iterator_t *)&iif); ics.valid; cs_iter_next(&ics)) {
+				if (ics.curr[1] != UVC_CS_INTERFACE) {
+					uwarnf("Unknown descriptor=%02X", ics.curr[1]);
+					continue;
+				}
+				switch (ics.curr[2]) {
+				case UVC_VC_HEADER:
+					uinfo("  VC_HEADER"); break;
+				case UVC_VC_INPUT_TERMINAL:
+					uinfof("    VC_INPUT_TERMINAL, ID=%d", ics.curr[3]); break;
+				case UVC_VC_OUTPUT_TERMINAL:
+					uinfof("    VC_OUTPUT_TERMINAL, ID=%d", ics.curr[3]); break;
+				case UVC_VC_SELECTOR_UNIT:
+					uinfof("    VC_SELECTOR_UNIT, ID=%d", ics.curr[3]); break;
+				case UVC_VC_PROCESSING_UNIT:
+					uinfof("    VC_PROCESSING_UNIT, ID=%d", ics.curr[3]); break;
+				case UVC_VC_EXTENSION_UNIT:
+					uinfof("    VC_EXTENSION_UNIT, ID=%d", ics.curr[3]); break;
+				default:
+					uwarnf("Unknown video bDescriptorSubtype=%02x", ics.curr[2]);
+					break;
+				}
+			}
+			break;
+		case UVC_SC_VIDEOSTREAMING:
+			if (uvcdp->ivs.curr == NULL) {
+				uvcdp->ivs = iif;
+			}
+			for (cs_iter_init(&ics, (generic_iterator_t *)&iif); ics.valid; cs_iter_next(&ics)) {
+				if (ics.curr[1] != UVC_CS_INTERFACE) {
+					uwarnf("Unknown descriptor=%02X", ics.curr[1]);
+					continue;
+				}
+				switch (ics.curr[2]) {
+				case UVC_VS_INPUT_HEADER:
+					uinfo("  VS_INPUT_HEADER"); break;
+				case UVC_VS_OUTPUT_HEADER:
+					uinfo("  VS_OUTPUT_HEADER"); break;
+				case UVC_VS_STILL_IMAGE_FRAME:
+					uinfo("    VS_STILL_IMAGE_FRAME"); break;
+
+				case UVC_VS_FORMAT_UNCOMPRESSED:
+					uinfof("    VS_FORMAT_UNCOMPRESSED, bFormatIndex=%d", ics.curr[3]); break;
+				case UVC_VS_FORMAT_MPEG2TS:
+					uinfof("    VS_FORMAT_MPEG2TS, bFormatIndex=%d", ics.curr[3]); break;
+				case UVC_VS_FORMAT_DV:
+					uinfof("    VS_FORMAT_DV, bFormatIndex=%d", ics.curr[3]); break;
+				case UVC_VS_FORMAT_MJPEG:
+					uinfof("    VS_FORMAT_MJPEG, bFormatIndex=%d", ics.curr[3]); break;
+				case UVC_VS_FORMAT_FRAME_BASED:
+					uinfof("    VS_FORMAT_FRAME_BASED, bFormatIndex=%d", ics.curr[3]); break;
+				case UVC_VS_FORMAT_STREAM_BASED:
+					uinfof("    VS_FORMAT_STREAM_BASED, bFormatIndex=%d", ics.curr[3]); break;
+
+				case UVC_VS_FRAME_UNCOMPRESSED:
+					uinfof("      VS_FRAME_UNCOMPRESSED, bFrameIndex=%d", ics.curr[3]); break;
+				case UVC_VS_FRAME_MJPEG:
+					uinfof("      VS_FRAME_MJPEG, bFrameIndex=%d", ics.curr[3]); break;
+				case UVC_VS_FRAME_FRAME_BASED:
+					uinfof("      VS_FRAME_FRAME_BASED, bFrameIndex=%d", ics.curr[3]); break;
+
+				case UVC_VS_COLOR_FORMAT:
+					uinfo("      VS_COLOR_FORMAT"); break;
+				default:
+					uwarnf("Unknown video bDescriptorSubtype=%02x", ics.curr[2]);
+					break;
+				}
+			}
+			break;
+		default:
+			uwarnf("Unknown video bInterfaceSubClass=%02x", ifdesc->bInterfaceSubClass);
+			break;
+		}
+
+		for (ep_iter_init(&iep, &iif); iep.valid; ep_iter_next(&iep)) {
+			const usbh_endpoint_descriptor_t *const epdesc = ep_get(&iep);
+
+			if ((ifdesc->bInterfaceSubClass == UVC_SC_VIDEOCONTROL)
+					&& ((epdesc->bmAttributes & 0x03) == USBH_EPTYPE_INT)
+					&& ((epdesc->bEndpointAddress & 0x80) ==  USBH_EPDIR_IN)) {
+				/* found VC interrupt endpoint */
+				uinfof("  VC Interrupt endpoint; %02x, bInterval=%d",
+						epdesc->bEndpointAddress, epdesc->bInterval);
+				usbhEPObjectInit(&uvcdp->ep_int, dev, epdesc);
+				usbhEPSetName(&uvcdp->ep_int, "UVC[INT ]");
+			} else if ((ifdesc->bInterfaceSubClass == UVC_SC_VIDEOSTREAMING)
+					&& ((epdesc->bmAttributes & 0x03) == USBH_EPTYPE_ISO)
+					&& ((epdesc->bEndpointAddress & 0x80) ==  USBH_EPDIR_IN)) {
+				/* found VS isochronous endpoint */
+				uinfof("  VS Isochronous endpoint; %02x, bInterval=%d, bmAttributes=%02x",
+						epdesc->bEndpointAddress, epdesc->bInterval, epdesc->bmAttributes);
+			} else {
+				/* unknown EP */
+				uwarnf("  <unknown endpoint>, bEndpointAddress=%02x, bmAttributes=%02x",
+									epdesc->bEndpointAddress, epdesc->bmAttributes);
+			}
+
+			for (cs_iter_init(&ics, &iep); ics.valid; cs_iter_next(&ics)) {
+				uinfof("    CS_ENDPOINT bLength=%d, bDescriptorType=%02X",
+						ics.curr[0], ics.curr[1]);
+			}
+		}
+	}
+
+	if ((uvcdp->ivc.curr == NULL) || (uvcdp->ivs.curr == NULL)) {
+		return NULL;
+	}
+
+//	uvcdp->dev = dev;
+
+	_set_vs_alternate(uvcdp, 0);
+
+	/* initialize the INT endpoint */
+	chPoolObjectInit(&uvcdp->mp_status, sizeof(usbhuvc_message_status_t), NULL);
+	for(i = 0; i < HAL_USBHUVC_STATUS_PACKETS_COUNT; i++)
+		chPoolFree(&uvcdp->mp_status, &uvcdp->mp_status_buffer[i]);
+
+	usbhEPOpen(&uvcdp->ep_int);
+
+	usbhuvc_message_status_t *const msg = (usbhuvc_message_status_t *)chPoolAlloc(&uvcdp->mp_status);
+	osalDbgCheck(msg);
+	usbhURBObjectInit(&uvcdp->urb_int, &uvcdp->ep_int, _cb_int, uvcdp, msg->data, USBHUVC_MAX_STATUS_PACKET_SZ);
+	osalSysLock();
+	usbhURBSubmitI(&uvcdp->urb_int);
+	uvcdp->state = USBHUVC_STATE_ACTIVE;
+	osalOsRescheduleS();
+	osalSysUnlock();
+
+	dev->keepFullCfgDesc++;
+	return (usbh_baseclassdriver_t *)uvcdp;
 }
 
 static void uvc_unload(usbh_baseclassdriver_t *drv) {
-	(void)drv;
+	USBHUVCDriver *const uvcdp = (USBHUVCDriver *)drv;
+
+	usbhuvcStreamStop(uvcdp);
+
+	usbhEPClose(&uvcdp->ep_int);
+
+	//TODO: free
+
+	if (drv->dev->keepFullCfgDesc)
+		drv->dev->keepFullCfgDesc--;
+
+	osalSysLock();
+	uvcdp->state = USBHUVC_STATE_STOP;
+	osalSysUnlock();
+}
+
+void usbhuvcInit(void) {
+	uint8_t i;
+	for (i = 0; i < HAL_USBHUVC_MAX_INSTANCES; i++) {
+		usbhuvcObjectInit(&USBHUVCD[i]);
+	}
 }
 
 #endif