drivers: uhc: interrupt transaction handling

Add interrupt and start frame parameters and schedule transaction at
specific frame. Implement for virtual driver only.

Signed-off-by: Johann Fischer <johann.fischer@nordicsemi.no>

Author: jfischer-no

drivers/usb/uhc/uhc_virtual.c

@@ -49,6 +49,7 @@ struct uhc_vrt_data {
 	struct uhc_transfer *last_xfer;
 	struct uhc_vrt_frame frame;
 	struct k_timer sof_timer;
+	uint16_t frame_number;
 	uint8_t req;
 };
 
@@ -224,6 +225,16 @@ static void vrt_assemble_frame(const struct device *dev)
 			continue;
 		}
 
+		if (tmp->interval) {
+			if (tmp->start_frame != priv->frame_number) {
+				continue;
+			}
+
+			tmp->start_frame = priv->frame_number + tmp->interval;
+			LOG_DBG("Interrupt transfer s.f. %u f.n. %u interval %u",
+				tmp->start_frame, priv->frame_number, tmp->interval);
+		}
+
 		bm |= BIT(idx);
 		frame->slots[n].xfer = tmp;
 		sys_dlist_append(&frame->list, &frame->slots[n].node);
@@ -410,6 +421,7 @@ static void xfer_work_handler(struct k_work *work)
 
 		switch (ev->type) {
 		case UHC_VRT_EVT_SOF:
+			priv->frame_number++;
 			vrt_xfer_cleanup_cancelled(dev);
 			vrt_assemble_frame(dev);
 			schedule = true;
@@ -533,6 +545,14 @@ static int uhc_vrt_bus_resume(const struct device *dev)
 static int uhc_vrt_enqueue(const struct device *dev,
 			   struct uhc_transfer *const xfer)
 {
+	struct uhc_vrt_data *priv = uhc_get_private(dev);
+
+	if (xfer->interval) {
+		xfer->start_frame = priv->frame_number + xfer->interval;
+		LOG_DBG("New interrupt transfer s.f. %u f.n. %u interval %u",
+			xfer->start_frame, priv->frame_number, xfer->interval);
+	}
+
 	uhc_xfer_append(dev, xfer);
 
 	return 0;

include/zephyr/drivers/usb/uhc.h

@@ -81,6 +81,10 @@ struct uhc_transfer {
 	uint8_t ep;
 	/** Maximum packet size */
 	uint16_t mps;
+	/** Interval, used for periodic transfers only */
+	uint16_t interval;
+	/** Start frame, used for periodic transfers only */
+	uint16_t start_frame;
 	/** Flag marks request buffer is queued */
 	unsigned int queued : 1;
 	/** Control stage status, up to the driver to use it or not */