*
* Issue has been fixed in DEV_VER_V3 version of controller.
*
+ * Work around 2:
+ * Controller for OUT endpoints has shared on-chip buffers for all incoming
+ * packets, including ep0out. It's FIFO buffer, so packets must be handle by DMA
+ * in correct order. If the first packet in the buffer will not be handled,
+ * then the following packets directed for other endpoints and functions
+ * will be blocked.
+ * Additionally the packets directed to one endpoint can block entire on-chip
+ * buffers. In this case transfer to other endpoints also will blocked.
+ *
+ * To resolve this issue after raising the descriptor missing interrupt
+ * driver prepares internal usb_request object and use it to arm DMA transfer.
+ *
+ * The problematic situation was observed in case when endpoint has been enabled
+ * but no usb_request were queued. Driver try detects such endpoints and will
+ * use this workaround only for these endpoint.
+ *
+ * Driver use limited number of buffer. This number can be set by macro
+ * CDNS3_WA2_NUM_BUFFERS.
+ *
+ * Such blocking situation was observed on ACM gadget. For this function
+ * host send OUT data packet but ACM function is not prepared for this packet.
+ * It's cause that buffer placed in on chip memory block transfer to other
+ * endpoints.
+ *
+ * Issue has been fixed in DEV_VER_V2 version of controller.
+ *
*/
#include <linux/dma-mapping.h>
}
/**
+ * cdns3_next_priv_request - returns next request from list
+ * @list: list containing requests
+ *
+ * Returns request or NULL if no requests in list
+ */
+struct cdns3_request *cdns3_next_priv_request(struct list_head *list)
+{
+ return list_first_entry_or_null(list, struct cdns3_request, list);
+}
+
+/**
* select_ep - selects endpoint
* @priv_dev: extended gadget object
* @ep: endpoint address
return ret;
}
+/*
+ * WA2: Set flag for all not ISOC OUT endpoints. If this flag is set
+ * driver try to detect whether endpoint need additional internal
+ * buffer for unblocking on-chip FIFO buffer. This flag will be cleared
+ * if before first DESCMISS interrupt the DMA will be armed.
+ */
+#define cdns3_wa2_enable_detection(priv_dev, ep_priv, reg) do { \
+ if (!priv_ep->dir && priv_ep->type != USB_ENDPOINT_XFER_ISOC) { \
+ priv_ep->flags |= EP_QUIRK_EXTRA_BUF_DET; \
+ (reg) |= EP_STS_EN_DESCMISEN; \
+ } } while (0)
+
+/**
+ * cdns3_wa2_descmiss_copy_data copy data from internal requests to
+ * request queued by class driver.
+ * @priv_ep: extended endpoint object
+ * @request: request object
+ */
+static void cdns3_wa2_descmiss_copy_data(struct cdns3_endpoint *priv_ep,
+ struct usb_request *request)
+{
+ struct usb_request *descmiss_req;
+ struct cdns3_request *descmiss_priv_req;
+
+ while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+ int chunk_end;
+ int length;
+
+ descmiss_priv_req =
+ cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+ descmiss_req = &descmiss_priv_req->request;
+
+ /* driver can't touch pending request */
+ if (descmiss_priv_req->flags & REQUEST_PENDING)
+ break;
+
+ chunk_end = descmiss_priv_req->flags & REQUEST_INTERNAL_CH;
+ length = request->actual + descmiss_req->actual;
+
+ request->status = descmiss_req->status;
+
+ if (length <= request->length) {
+ memcpy(&((u8 *)request->buf)[request->actual],
+ descmiss_req->buf,
+ descmiss_req->actual);
+ request->actual = length;
+ } else {
+ /* It should never occures */
+ request->status = -ENOMEM;
+ }
+
+ list_del_init(&descmiss_priv_req->list);
+
+ kfree(descmiss_req->buf);
+ cdns3_gadget_ep_free_request(&priv_ep->endpoint, descmiss_req);
+ --priv_ep->wa2_counter;
+
+ if (!chunk_end)
+ break;
+ }
+}
+
+struct usb_request *cdns3_wa2_gadget_giveback(struct cdns3_device *priv_dev,
+ struct cdns3_endpoint *priv_ep,
+ struct cdns3_request *priv_req)
+{
+ if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN &&
+ priv_req->flags & REQUEST_INTERNAL) {
+ struct usb_request *req;
+
+ req = cdns3_next_request(&priv_ep->deferred_req_list);
+
+ priv_ep->descmis_req = NULL;
+
+ if (!req)
+ return NULL;
+
+ cdns3_wa2_descmiss_copy_data(priv_ep, req);
+ if (!(priv_ep->flags & EP_QUIRK_END_TRANSFER) &&
+ req->length != req->actual) {
+ /* wait for next part of transfer */
+ return NULL;
+ }
+
+ if (req->status == -EINPROGRESS)
+ req->status = 0;
+
+ list_del_init(&req->list);
+ cdns3_start_all_request(priv_dev, priv_ep);
+ return req;
+ }
+
+ return &priv_req->request;
+}
+
+int cdns3_wa2_gadget_ep_queue(struct cdns3_device *priv_dev,
+ struct cdns3_endpoint *priv_ep,
+ struct cdns3_request *priv_req)
+{
+ int deferred = 0;
+
+ /*
+ * If transfer was queued before DESCMISS appear than we
+ * can disable handling of DESCMISS interrupt. Driver assumes that it
+ * can disable special treatment for this endpoint.
+ */
+ if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET) {
+ u32 reg;
+
+ cdns3_select_ep(priv_dev, priv_ep->num | priv_ep->dir);
+ priv_ep->flags &= ~EP_QUIRK_EXTRA_BUF_DET;
+ reg = readl(&priv_dev->regs->ep_sts_en);
+ reg &= ~EP_STS_EN_DESCMISEN;
+ writel(reg, &priv_dev->regs->ep_sts_en);
+ }
+
+ if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN) {
+ u8 pending_empty = list_empty(&priv_ep->pending_req_list);
+ u8 descmiss_empty = list_empty(&priv_ep->wa2_descmiss_req_list);
+
+ /*
+ * DESCMISS transfer has been finished, so data will be
+ * directly copied from internal allocated usb_request
+ * objects.
+ */
+ if (pending_empty && !descmiss_empty &&
+ !(priv_req->flags & REQUEST_INTERNAL)) {
+ cdns3_wa2_descmiss_copy_data(priv_ep,
+ &priv_req->request);
+ list_add_tail(&priv_req->request.list,
+ &priv_ep->pending_req_list);
+ cdns3_gadget_giveback(priv_ep, priv_req,
+ priv_req->request.status);
+
+ /*
+ * Intentionally driver returns positive value as
+ * correct value. It informs that transfer has
+ * been finished.
+ */
+ return EINPROGRESS;
+ }
+
+ /*
+ * Driver will wait for completion DESCMISS transfer,
+ * before starts new, not DESCMISS transfer.
+ */
+ if (!pending_empty && !descmiss_empty)
+ deferred = 1;
+
+ if (priv_req->flags & REQUEST_INTERNAL)
+ list_add_tail(&priv_req->list,
+ &priv_ep->wa2_descmiss_req_list);
+ }
+
+ return deferred;
+}
+
+static void cdsn3_wa2_remove_old_request(struct cdns3_endpoint *priv_ep)
+{
+ struct cdns3_request *priv_req;
+
+ while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+ u8 chain;
+
+ priv_req = cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+ chain = !!(priv_req->flags & REQUEST_INTERNAL_CH);
+
+ kfree(priv_req->request.buf);
+ cdns3_gadget_ep_free_request(&priv_ep->endpoint,
+ &priv_req->request);
+ list_del_init(&priv_req->list);
+ --priv_ep->wa2_counter;
+
+ if (!chain)
+ break;
+ }
+}
+
+/**
+ * cdns3_wa2_descmissing_packet - handles descriptor missing event.
+ * @priv_dev: extended gadget object
+ *
+ * This function is used only for WA2. For more information see Work around 2
+ * description.
+ */
+static void cdns3_wa2_descmissing_packet(struct cdns3_endpoint *priv_ep)
+{
+ struct cdns3_request *priv_req;
+ struct usb_request *request;
+
+ if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET) {
+ priv_ep->flags &= ~EP_QUIRK_EXTRA_BUF_DET;
+ priv_ep->flags |= EP_QUIRK_EXTRA_BUF_EN;
+ }
+
+ cdns3_dbg(priv_ep->cdns3_dev, "WA2: Description Missing detected\n");
+
+ if (priv_ep->wa2_counter >= CDNS3_WA2_NUM_BUFFERS)
+ cdsn3_wa2_remove_old_request(priv_ep);
+
+ request = cdns3_gadget_ep_alloc_request(&priv_ep->endpoint,
+ GFP_ATOMIC);
+ if (!request)
+ goto err;
+
+ priv_req = to_cdns3_request(request);
+ priv_req->flags |= REQUEST_INTERNAL;
+
+ /* if this field is still assigned it indicate that transfer related
+ * with this request has not been finished yet. Driver in this
+ * case simply allocate next request and assign flag REQUEST_INTERNAL_CH
+ * flag to previous one. It will indicate that current request is
+ * part of the previous one.
+ */
+ if (priv_ep->descmis_req)
+ priv_ep->descmis_req->flags |= REQUEST_INTERNAL_CH;
+
+ priv_req->request.buf = kzalloc(CDNS3_DESCMIS_BUF_SIZE,
+ GFP_ATOMIC);
+ priv_ep->wa2_counter++;
+
+ if (!priv_req->request.buf) {
+ cdns3_gadget_ep_free_request(&priv_ep->endpoint, request);
+ goto err;
+ }
+
+ priv_req->request.length = CDNS3_DESCMIS_BUF_SIZE;
+ priv_ep->descmis_req = priv_req;
+
+ __cdns3_gadget_ep_queue(&priv_ep->endpoint,
+ &priv_ep->descmis_req->request,
+ GFP_ATOMIC);
+
+ return;
+
+err:
+ dev_err(priv_ep->cdns3_dev->dev,
+ "Failed: No sufficient memory for DESCMIS\n");
+}
+
/**
* cdns3_gadget_giveback - call struct usb_request's ->complete callback
* @priv_ep: The endpoint to whom the request belongs to
priv_req->flags &= ~(REQUEST_PENDING | REQUEST_UNALIGNED);
trace_cdns3_gadget_giveback(priv_req);
+ if (priv_dev->dev_ver < DEV_VER_V2) {
+ request = cdns3_wa2_gadget_giveback(priv_dev, priv_ep,
+ priv_req);
+ if (!request)
+ return;
+ }
+
if (request->complete) {
spin_unlock(&priv_dev->lock);
usb_gadget_giveback_request(&priv_ep->endpoint,
}
}
- if ((ep_sts_reg & EP_STS_IOC) || (ep_sts_reg & EP_STS_ISP))
+ if ((ep_sts_reg & EP_STS_IOC) || (ep_sts_reg & EP_STS_ISP)) {
+ if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN) {
+ if (ep_sts_reg & EP_STS_ISP)
+ priv_ep->flags |= EP_QUIRK_END_TRANSFER;
+ else
+ priv_ep->flags &= ~EP_QUIRK_END_TRANSFER;
+ }
+
cdns3_transfer_completed(priv_dev, priv_ep);
+ }
+
+ /*
+ * WA2: this condition should only be meet when
+ * priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET or
+ * priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN.
+ * In other cases this interrupt will be disabled/
+ */
+ if (ep_sts_reg & EP_STS_DESCMIS && priv_dev->dev_ver < DEV_VER_V2)
+ cdns3_wa2_descmissing_packet(priv_ep);
return 0;
}
cdns3_set_register_bit(&priv_dev->regs->ep_ien,
BIT(cdns3_ep_addr_to_index(bEndpointAddress)));
+ if (priv_dev->dev_ver < DEV_VER_V2)
+ cdns3_wa2_enable_detection(priv_dev, priv_ep, reg);
+
writel(reg, &priv_dev->regs->ep_sts_en);
/*
ep->desc = desc;
priv_ep->flags &= ~(EP_PENDING_REQUEST | EP_STALL |
- EP_QUIRK_ISO_OUT_EN);
+ EP_QUIRK_ISO_OUT_EN | EP_QUIRK_EXTRA_BUF_EN);
priv_ep->flags |= EP_ENABLED | EP_UPDATE_EP_TRBADDR;
priv_ep->wa1_set = 0;
priv_ep->enqueue = 0;
static int cdns3_gadget_ep_disable(struct usb_ep *ep)
{
struct cdns3_endpoint *priv_ep;
+ struct cdns3_request *priv_req;
struct cdns3_device *priv_dev;
struct usb_request *request;
unsigned long flags;
-ESHUTDOWN);
}
+ while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+ priv_req = cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+
+ kfree(priv_req->request.buf);
+ cdns3_gadget_ep_free_request(&priv_ep->endpoint,
+ &priv_req->request);
+ list_del_init(&priv_req->list);
+ --priv_ep->wa2_counter;
+ }
+
while (!list_empty(&priv_ep->deferred_req_list)) {
request = cdns3_next_request(&priv_ep->deferred_req_list);
-ESHUTDOWN);
}
+ priv_ep->descmis_req = NULL;
+
ep->desc = NULL;
priv_ep->flags &= ~EP_ENABLED;
priv_req = to_cdns3_request(request);
trace_cdns3_ep_queue(priv_req);
+ if (priv_dev->dev_ver < DEV_VER_V2) {
+ ret = cdns3_wa2_gadget_ep_queue(priv_dev, priv_ep,
+ priv_req);
+
+ if (ret == EINPROGRESS)
+ return 0;
+ }
+
ret = cdns3_prepare_aligned_request_buf(priv_req);
if (ret < 0)
return ret;
INIT_LIST_HEAD(&priv_ep->pending_req_list);
INIT_LIST_HEAD(&priv_ep->deferred_req_list);
+ INIT_LIST_HEAD(&priv_ep->wa2_descmiss_req_list);
}
return 0;