[RFC PATCH v2 10/15] usb:cdns3: Ep0 operations part of the API

[Pawel Laszczak <pawell@cadence.com>]

Patch implements related to default endpoint callback functions
defined in usb_ep_ops object

Signed-off-by: Pawel Laszczak <pawell@cadence.com>
---
 drivers/usb/cdns3/ep0.c    | 191 ++++++++++++++++++++++++++++++++++++-
 drivers/usb/cdns3/gadget.c |   8 ++
 drivers/usb/cdns3/gadget.h |  10 ++
 3 files changed, 207 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/cdns3/ep0.c b/drivers/usb/cdns3/ep0.c
index ca1795467155..d05169e73631 100644
--- a/drivers/usb/cdns3/ep0.c
+++ b/drivers/usb/cdns3/ep0.c
@@ -18,11 +18,185 @@ static struct usb_endpoint_descriptor cdns3_gadget_ep0_desc = {
 	.bmAttributes =	USB_ENDPOINT_XFER_CONTROL,
 };
 
+/**
+ * cdns3_ep0_run_transfer - Do transfer on default endpoint hardware
+ * @priv_dev: extended gadget object
+ * @dma_addr: physical address where data is/will be stored
+ * @length: data length
+ * @erdy: set it to 1 when ERDY packet should be sent -
+ *        exit from flow control state
+ */
+static void cdns3_ep0_run_transfer(struct cdns3_device *priv_dev,
+				   dma_addr_t dma_addr,
+				   unsigned int length, int erdy)
+{
+	struct cdns3_usb_regs __iomem *regs = priv_dev->regs;
+
+	priv_dev->trb_ep0->buffer = TRB_BUFFER(dma_addr);
+	priv_dev->trb_ep0->length = TRB_LEN(length);
+	priv_dev->trb_ep0->control = TRB_CYCLE | TRB_IOC | TRB_TYPE(TRB_NORMAL);
+
+	cdns3_select_ep(priv_dev,
+			priv_dev->ep0_data_dir ? USB_DIR_IN : USB_DIR_OUT);
+
+	writel(EP_STS_TRBERR, &regs->ep_sts);
+	writel(EP_TRADDR_TRADDR(priv_dev->trb_ep0_dma), &regs->ep_traddr);
+
+	dev_dbg(&priv_dev->dev, "//Ding Dong ep0%s\n",
+		priv_dev->ep0_data_dir ? "IN" : "OUT");
+
+	/* TRB should be prepared before starting transfer */
+	writel(EP_CMD_DRDY, &regs->ep_cmd);
+
+	if (erdy)
+		writel(EP_CMD_ERDY, &priv_dev->regs->ep_cmd);
+}
+
 static void cdns3_prepare_setup_packet(struct cdns3_device *priv_dev)
 {
 	//TODO: Implements this function
 }
 
+static void cdns3_set_hw_configuration(struct cdns3_device *priv_dev)
+{
+	struct cdns3_endpoint *priv_ep;
+	struct usb_request *request;
+	struct usb_ep *ep;
+	int result = 0;
+
+	if (priv_dev->hw_configured_flag)
+		return;
+
+	writel(USB_CONF_CFGSET, &priv_dev->regs->usb_conf);
+	writel(EP_CMD_ERDY | EP_CMD_REQ_CMPL, &priv_dev->regs->ep_cmd);
+
+	cdns3_set_register_bit(&priv_dev->regs->usb_conf,
+			       USB_CONF_U1EN | USB_CONF_U2EN);
+
+	/* wait until configuration set */
+	result = cdns3_handshake(&priv_dev->regs->usb_sts,
+				 USB_STS_CFGSTS_MASK, 1, 100);
+
+	priv_dev->hw_configured_flag = 1;
+	cdns3_enable_l1(priv_dev, 1);
+
+	list_for_each_entry(ep, &priv_dev->gadget.ep_list, ep_list) {
+		if (ep->enabled) {
+			priv_ep = ep_to_cdns3_ep(ep);
+			request = cdns3_next_request(&priv_ep->request_list);
+			if (request)
+				cdns3_ep_run_transfer(priv_ep, request);
+		}
+	}
+}
+
+/**
+ * cdns3_gadget_ep0_enable
+ * Function shouldn't be called by gadget driver,
+ * endpoint 0 is allways active
+ */
+static int cdns3_gadget_ep0_enable(struct usb_ep *ep,
+				   const struct usb_endpoint_descriptor *desc)
+{
+	return -EINVAL;
+}
+
+/**
+ * cdns3_gadget_ep0_disable
+ * Function shouldn't be called by gadget driver,
+ * endpoint 0 is allways active
+ */
+static int cdns3_gadget_ep0_disable(struct usb_ep *ep)
+{
+	return -EINVAL;
+}
+
+/**
+ * cdns3_gadget_ep0_set_halt
+ * @ep: pointer to endpoint zero object
+ * @value: 1 for set stall, 0 for clear stall
+ *
+ * Returns 0
+ */
+static int cdns3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
+{
+	/* TODO */
+	return 0;
+}
+
+/**
+ * cdns3_gadget_ep0_queue Transfer data on endpoint zero
+ * @ep: pointer to endpoint zero object
+ * @request: pointer to request object
+ * @gfp_flags: gfp flags
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_gadget_ep0_queue(struct usb_ep *ep,
+				  struct usb_request *request,
+				  gfp_t gfp_flags)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	unsigned long flags;
+	int erdy_sent = 0;
+	int ret = 0;
+
+	dev_dbg(&priv_dev->dev, "Queue to Ep0%s L: %d\n",
+		priv_dev->ep0_data_dir ? "IN" : "OUT",
+		request->length);
+
+	/* send STATUS stage */
+	if (request->length == 0 && request->zero == 0) {
+		spin_lock_irqsave(&priv_dev->lock, flags);
+		cdns3_select_ep(priv_dev, 0x00);
+
+		erdy_sent = !priv_dev->hw_configured_flag;
+		cdns3_set_hw_configuration(priv_dev);
+
+		if (!erdy_sent)
+			writel(EP_CMD_ERDY | EP_CMD_REQ_CMPL,
+			       &priv_dev->regs->ep_cmd);
+
+		cdns3_prepare_setup_packet(priv_dev);
+		request->actual = 0;
+		priv_dev->status_completion_no_call = true;
+		priv_dev->pending_status_request = request;
+		spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+		/*
+		 * Since there is no completion interrupt for status stage,
+		 * it needs to call ->completion in software after
+		 * ep0_queue is back.
+		 */
+		queue_work(system_freezable_wq, &priv_dev->pending_status_wq);
+		return 0;
+	}
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	if (!list_empty(&priv_ep->request_list)) {
+		dev_err(&priv_dev->dev,
+			"can't handle multiple requests for ep0\n");
+		spin_unlock_irqrestore(&priv_dev->lock, flags);
+		return -EOPNOTSUPP;
+	}
+
+	ret = usb_gadget_map_request_by_dev(priv_dev->sysdev, request,
+					    priv_dev->ep0_data_dir);
+	if (ret) {
+		spin_unlock_irqrestore(&priv_dev->lock, flags);
+		dev_err(&priv_dev->dev, "failed to map request\n");
+		return -EINVAL;
+	}
+
+	priv_dev->ep0_request = request;
+	list_add_tail(&request->list, &priv_ep->request_list);
+	cdns3_ep0_run_transfer(priv_dev, request->dma, request->length, 1);
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+	return ret;
+}
+
 /**
  * cdns3_gadget_ep_set_wedge Set wedge on selected endpoint
  * @ep: endpoint object
@@ -41,6 +215,17 @@ int cdns3_gadget_ep_set_wedge(struct usb_ep *ep)
 	return 0;
 }
 
+const struct usb_ep_ops cdns3_gadget_ep0_ops = {
+	.enable = cdns3_gadget_ep0_enable,
+	.disable = cdns3_gadget_ep0_disable,
+	.alloc_request = cdns3_gadget_ep_alloc_request,
+	.free_request = cdns3_gadget_ep_free_request,
+	.queue = cdns3_gadget_ep0_queue,
+	.dequeue = cdns3_gadget_ep_dequeue,
+	.set_halt = cdns3_gadget_ep0_set_halt,
+	.set_wedge = cdns3_gadget_ep_set_wedge,
+};
+
 /**
  * cdns3_ep0_config - Configures default endpoint
  * @priv_dev: extended gadget object
@@ -62,6 +247,9 @@ void cdns3_ep0_config(struct cdns3_device *priv_dev)
 		priv_dev->ep0_request = NULL;
 	}
 
+	priv_dev->u1_allowed = 0;
+	priv_dev->u2_allowed = 0;
+
 	priv_dev->gadget.ep0->maxpacket = max_packet_size;
 	cdns3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(max_packet_size);
 
@@ -106,8 +294,7 @@ int cdns3_init_ep0(struct cdns3_device *priv_dev)
 	sprintf(ep0->name, "ep0");
 
 	/* fill linux fields */
-	//TODO: implements cdns3_gadget_ep0_ops object
-	//ep0->endpoint.ops = &cdns3_gadget_ep0_ops;
+	ep0->endpoint.ops = &cdns3_gadget_ep0_ops;
 	ep0->endpoint.maxburst = 1;
 	usb_ep_set_maxpacket_limit(&ep0->endpoint, ENDPOINT0_MAX_PACKET_LIMIT);
 	ep0->endpoint.address = 0;
diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
index 1f2a434486dc..c965da16c0c8 100644
--- a/drivers/usb/cdns3/gadget.c
+++ b/drivers/usb/cdns3/gadget.c
@@ -188,6 +188,14 @@ static void cdns3_ep_stall_flush(struct cdns3_endpoint *priv_ep)
 	priv_ep->flags |= EP_STALL;
 }
 
+void cdns3_enable_l1(struct cdns3_device *priv_dev, int enable)
+{
+	if (enable)
+		writel(USB_CONF_L1EN, &priv_dev->regs->usb_conf);
+	else
+		writel(USB_CONF_L1DS, &priv_dev->regs->usb_conf);
+}
+
 /**
  * cdns3_gadget_giveback - call struct usb_request's ->complete callback
  * @priv_ep: The endpoint to whom the request belongs to
diff --git a/drivers/usb/cdns3/gadget.h b/drivers/usb/cdns3/gadget.h
index a4be288b34cb..224f6b830bc9 100644
--- a/drivers/usb/cdns3/gadget.h
+++ b/drivers/usb/cdns3/gadget.h
@@ -1068,11 +1068,21 @@ struct cdns3_device {
 	struct usb_request		*pending_status_request;
 };
 
+int cdns3_handshake(void __iomem *ptr, u32 mask, u32 done, int usec);
 void cdns3_set_register_bit(void __iomem *ptr, u32 mask);
 int cdns3_init_ep0(struct cdns3_device *priv_dev);
 void cdns3_ep0_config(struct cdns3_device *priv_dev);
 void cdns3_select_ep(struct cdns3_device *priv_dev, u32 ep);
+void cdns3_enable_l1(struct cdns3_device *priv_dev, int enable);
+struct usb_request *cdns3_next_request(struct list_head *list);
+int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
+			  struct usb_request *request);
 int cdns3_gadget_ep_set_wedge(struct usb_ep *ep);
 int cdns3_gadget_ep_set_halt(struct usb_ep *ep, int value);
+struct usb_request *cdns3_gadget_ep_alloc_request(struct usb_ep *ep,
+						  gfp_t gfp_flags);
+void cdns3_gadget_ep_free_request(struct usb_ep *ep,
+				  struct usb_request *request);
+int cdns3_gadget_ep_dequeue(struct usb_ep *ep, struct usb_request *request);
 
 #endif /* __LINUX_CDNS3_GADGET */
-- 
2.17.1