Non-isochronous transfers:
dwc2_gadget_config_nonisoc_xfer_ddma() name is prepended with underscore
and the function is adapted to process descriptors passed from outside
and to handle end of current sg list element differently from handling
the end of the entire buffer. A wrapper for the said function is added
which, for sg mode, iterates over scatterlist elements and for each of
them calls the function mentioned above.
Isochronous transfers:
If the usb request contains a scatterlist, the address from the first
element is used as dma address at dwc2_gadget_fill_isoc_desc() invocations.
Current code for isoc transfers does not allow more than 4096 bytes per
transfer, so it is assumed there is only one element in the scatterlist.
If there are more, a warning is issued. Please see the fragment under
the comment:
/* In DDMA mode for ISOC's don't queue request if length greater
* than descriptor limits.
*/
in dwc2_hsotg_ep_queue() to see the limits for isoc transfers.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@xxxxxxxxxxx>
---
@Minas: I was actually unable to test the isochronous transfers.
drivers/usb/dwc2/gadget.c | 104 ++++++++++++++++++++++++++++++++--------------
1 file changed, 73 insertions(+), 31 deletions(-)
diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index d9bb6cb..90df8f4 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -768,22 +768,13 @@ static u32 dwc2_gadget_get_desc_params(struct dwc2_hsotg_ep *hs_ep, u32 *mask)
return desc_size;
}
-/*
- * dwc2_gadget_config_nonisoc_xfer_ddma - prepare non ISOC DMA desc chain.
- * @hs_ep: The endpoint
- * @dma_buff: DMA address to use
- * @len: Length of the transfer
- *
- * This function will iterate over descriptor chain and fill its entries
- * with corresponding information based on transfer data.
- */
-static void dwc2_gadget_config_nonisoc_xfer_ddma(struct dwc2_hsotg_ep *hs_ep,
+static void _dwc2_gadget_config_nonisoc_xfer_ddma(struct dwc2_hsotg_ep *hs_ep,
+ struct dwc2_dma_desc **desc,
dma_addr_t dma_buff,
- unsigned int len)
+ unsigned int len,
+ bool true_last)
{
- struct dwc2_hsotg *hsotg = hs_ep->parent;
int dir_in = hs_ep->dir_in;
- struct dwc2_dma_desc *desc = hs_ep->desc_list;
u32 mps = hs_ep->ep.maxpacket;
u32 maxsize = 0;
u32 offset = 0;
@@ -798,42 +789,80 @@ static void dwc2_gadget_config_nonisoc_xfer_ddma(struct dwc2_hsotg_ep *hs_ep,
hs_ep->desc_count = 1;
for (i = 0; i < hs_ep->desc_count; ++i) {
- desc->status = 0;
- desc->status |= (DEV_DMA_BUFF_STS_HBUSY
+ (*desc)->status = 0;
+ (*desc)->status |= (DEV_DMA_BUFF_STS_HBUSY
<< DEV_DMA_BUFF_STS_SHIFT);
if (len > maxsize) {
if (!hs_ep->index && !dir_in)
- desc->status |= (DEV_DMA_L | DEV_DMA_IOC);
+ (*desc)->status |= (DEV_DMA_L | DEV_DMA_IOC);
- desc->status |= (maxsize <<
- DEV_DMA_NBYTES_SHIFT & mask);
- desc->buf = dma_buff + offset;
+ (*desc)->status |=
+ maxsize << DEV_DMA_NBYTES_SHIFT & mask;
+ (*desc)->buf = dma_buff + offset;
len -= maxsize;
offset += maxsize;
} else {
- desc->status |= (DEV_DMA_L | DEV_DMA_IOC);
+ if (true_last)
+ (*desc)->status |= (DEV_DMA_L | DEV_DMA_IOC);
if (dir_in)
- desc->status |= (len % mps) ? DEV_DMA_SHORT :
- ((hs_ep->send_zlp) ? DEV_DMA_SHORT : 0);
- if (len > maxsize)
- dev_err(hsotg->dev, "wrong len %d\n", len);
+ (*desc)->status |= (len % mps) ? DEV_DMA_SHORT :
+ ((hs_ep->send_zlp && true_last) ?
+ DEV_DMA_SHORT : 0);
- desc->status |=
+ (*desc)->status |=
len << DEV_DMA_NBYTES_SHIFT & mask;
- desc->buf = dma_buff + offset;
+ (*desc)->buf = dma_buff + offset;
}
- desc->status &= ~DEV_DMA_BUFF_STS_MASK;
- desc->status |= (DEV_DMA_BUFF_STS_HREADY
+ (*desc)->status &= ~DEV_DMA_BUFF_STS_MASK;
+ (*desc)->status |= (DEV_DMA_BUFF_STS_HREADY
<< DEV_DMA_BUFF_STS_SHIFT);
- desc++;
+ (*desc)++;
}
}
/*
+ * dwc2_gadget_config_nonisoc_xfer_ddma - prepare non ISOC DMA desc chain.
+ * @hs_ep: The endpoint
+ * @dma_buff: DMA address to use
+ * @len: Length of the transfer
+ *
+ * This function will iterate over descriptor chain and fill its entries
+ * with corresponding information based on transfer data.
+ */
+static void dwc2_gadget_config_nonisoc_xfer_ddma(struct dwc2_hsotg_ep *hs_ep,
+ dma_addr_t dma_buff,
+ unsigned int len)
+{
+ struct usb_request *ureq = &hs_ep->req->req;
+ struct dwc2_dma_desc *desc = hs_ep->desc_list;
+ struct scatterlist *sg;
+ int i;
+ u8 desc_count = 0;
+
+ /* non-DMA sg buffer */
+ if (!ureq->num_sgs) {
+ _dwc2_gadget_config_nonisoc_xfer_ddma(hs_ep, &desc,
+ dma_buff, len, true);
+
+ return;
+ }
+
+ /* DMA sg buffer */
+ for_each_sg(ureq->sg, sg, ureq->num_sgs, i) {
+ _dwc2_gadget_config_nonisoc_xfer_ddma(hs_ep, &desc,
+ sg_dma_address(sg) + sg->offset, sg_dma_len(sg),
+ sg_is_last(sg));
+ desc_count += hs_ep->desc_count;
+ }
+
+ hs_ep->desc_count = desc_count;
+}
+
+/*
* dwc2_gadget_fill_isoc_desc - fills next isochronous descriptor in chain.
* @hs_ep: The isochronous endpoint.
* @dma_buff: usb requests dma buffer.
@@ -944,7 +973,13 @@ static void dwc2_gadget_start_isoc_ddma(struct dwc2_hsotg_ep *hs_ep)
hs_ep->next_desc = 0;
list_for_each_entry_safe(hs_req, treq, &hs_ep->queue, queue) {
- ret = dwc2_gadget_fill_isoc_desc(hs_ep, hs_req->req.dma,
+ dma_addr_t dma_addr = hs_req->req.dma;
+
+ if (hs_req->req.num_sgs) {
+ WARN_ON(hs_req->req.num_sgs > 1);
+ dma_addr = sg_dma_address(hs_req->req.sg);
+ }
+ ret = dwc2_gadget_fill_isoc_desc(hs_ep, dma_addr,
hs_req->req.length);
if (ret)
break;
@@ -1399,7 +1434,13 @@ static int dwc2_hsotg_ep_queue(struct usb_ep *ep, struct usb_request *req,
*/
if (using_desc_dma(hs) && hs_ep->isochronous) {
if (hs_ep->target_frame != TARGET_FRAME_INITIAL) {
- dwc2_gadget_fill_isoc_desc(hs_ep, hs_req->req.dma,
+ dma_addr_t dma_addr = hs_req->req.dma;
+
+ if (hs_req->req.num_sgs) {
+ WARN_ON(hs_req->req.num_sgs > 1);
+ dma_addr = sg_dma_address(hs_req->req.sg);
+ }
+ dwc2_gadget_fill_isoc_desc(hs_ep, dma_addr,
hs_req->req.length);
}
return 0;
@@ -4364,6 +4405,7 @@ static int dwc2_hsotg_udc_start(struct usb_gadget *gadget,
hsotg->enabled = 0;
spin_unlock_irqrestore(&hsotg->lock, flags);
+ gadget->sg_supported = true;
dev_info(hsotg->dev, "bound driver %s\n", driver->driver.name);
return 0;
--
2.7.4
