usb: dwc3: gadget: use generic map/unmap routines

those routines have everything we need to map/unmap
USB requests and it's better to use them.

In order to achieve that, we had to add a simple
change on how we allocate and use our setup buffer;
we cannot allocate it from coherent anymore otherwise
the generic map/unmap routines won't be able to easily
know that the GetStatus request already has a DMA
address.

Signed-off-by: Felipe Balbi <balbi@ti.com>

4 files changed, 30 insertions, 83 deletions

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 9e57f8e9bf17..a72f42ffbbee 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -572,7 +572,6 @@ struct dwc3_request {
  * @ctrl_req_addr: dma address of ctrl_req
  * @ep0_trb: dma address of ep0_trb
  * @ep0_usb_req: dummy req used while handling STD USB requests
- * @setup_buf_addr: dma address of setup_buf
  * @ep0_bounce_addr: dma address of ep0_bounce
  * @lock: for synchronizing
  * @dev: pointer to our struct device
@@ -609,7 +608,6 @@ struct dwc3 {
         u8                      *setup_buf;
         dma_addr_t              ctrl_req_addr;
         dma_addr_t              ep0_trb_addr;
-        dma_addr_t              setup_buf_addr;
         dma_addr_t              ep0_bounce_addr;
         struct dwc3_request     ep0_usb_req;
         /* device lock */
diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 2f51de57593a..24137d8563c9 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -309,7 +309,7 @@ static int dwc3_ep0_handle_status(struct dwc3 *dwc,
         dep = dwc->eps[0];
         dwc->ep0_usb_req.dep = dep;
         dwc->ep0_usb_req.request.length = sizeof(*response_pkt);
-        dwc->ep0_usb_req.request.dma = dwc->setup_buf_addr;
+        dwc->ep0_usb_req.request.buf = dwc->setup_buf;
         dwc->ep0_usb_req.request.complete = dwc3_ep0_status_cmpl;
 
         return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
@@ -686,7 +686,12 @@ static void dwc3_ep0_do_control_data(struct dwc3 *dwc,
                                 DWC3_TRBCTL_CONTROL_DATA);
         } else if ((req->request.length % dep->endpoint.maxpacket)
                         && (event->endpoint_number == 0)) {
-                dwc3_map_buffer_to_dma(req);
+                ret = usb_gadget_map_request(&dwc->gadget, &req->request,
+                                event->endpoint_number);
+                if (ret) {
+                        dev_dbg(dwc->dev, "failed to map request\n");
+                        return;
+                }
 
                 WARN_ON(req->request.length > dep->endpoint.maxpacket);
 
@@ -701,7 +706,12 @@ static void dwc3_ep0_do_control_data(struct dwc3 *dwc,
                                 dwc->ep0_bounce_addr, dep->endpoint.maxpacket,
                                 DWC3_TRBCTL_CONTROL_DATA);
         } else {
-                dwc3_map_buffer_to_dma(req);
+                ret = usb_gadget_map_request(&dwc->gadget, &req->request,
+                                event->endpoint_number);
+                if (ret) {
+                        dev_dbg(dwc->dev, "failed to map request\n");
+                        return;
+                }
 
                 ret = dwc3_ep0_start_trans(dwc, event->endpoint_number,
                                 req->request.dma, req->request.length,
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index a1a04d00a9e4..1009e7e47a24 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -54,70 +54,6 @@
 #include "gadget.h"
 #include "io.h"
 
-#define DMA_ADDR_INVALID        (~(dma_addr_t)0)
-
-void dwc3_map_buffer_to_dma(struct dwc3_request *req)
-{
-        struct dwc3                     *dwc = req->dep->dwc;
-
-        if (req->request.length == 0) {
-                /* req->request.dma = dwc->setup_buf_addr; */
-                return;
-        }
-
-        if (req->request.num_sgs) {
-                int     mapped;
-
-                mapped = dma_map_sg(dwc->dev, req->request.sg,
-                                req->request.num_sgs,
-                                req->direction ? DMA_TO_DEVICE
-                                : DMA_FROM_DEVICE);
-                if (mapped < 0) {
-                        dev_err(dwc->dev, "failed to map SGs\n");
-                        return;
-                }
-
-                req->request.num_mapped_sgs = mapped;
-                return;
-        }
-
-        if (req->request.dma == DMA_ADDR_INVALID) {
-                req->request.dma = dma_map_single(dwc->dev, req->request.buf,
-                                req->request.length, req->direction
-                                ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
-                req->mapped = true;
-        }
-}
-
-void dwc3_unmap_buffer_from_dma(struct dwc3_request *req)
-{
-        struct dwc3                     *dwc = req->dep->dwc;
-
-        if (req->request.length == 0) {
-                req->request.dma = DMA_ADDR_INVALID;
-                return;
-        }
-
-        if (req->request.num_mapped_sgs) {
-                req->request.dma = DMA_ADDR_INVALID;
-                dma_unmap_sg(dwc->dev, req->request.sg,
-                                req->request.num_sgs,
-                                req->direction ? DMA_TO_DEVICE
-                                : DMA_FROM_DEVICE);
-
-                req->request.num_mapped_sgs = 0;
-                return;
-        }
-
-        if (req->mapped) {
-                dma_unmap_single(dwc->dev, req->request.dma,
-                                req->request.length, req->direction
-                                ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
-                req->mapped = 0;
-                req->request.dma = DMA_ADDR_INVALID;
-        }
-}
-
 void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
                 int status)
 {
@@ -144,14 +80,15 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
         if (req->request.status == -EINPROGRESS)
                 req->request.status = status;
 
-        dwc3_unmap_buffer_from_dma(req);
+        usb_gadget_unmap_request(&dwc->gadget, &req->request,
+                        req->direction);
 
         dev_dbg(dwc->dev, "request %p from %s completed %d/%d ===> %d\n",
                         req, dep->name, req->request.actual,
                         req->request.length, status);
 
         spin_unlock(&dwc->lock);
-        req->request.complete(&req->dep->endpoint, &req->request);
+        req->request.complete(&dep->endpoint, &req->request);
         spin_lock(&dwc->lock);
 }
 
@@ -563,7 +500,6 @@ static struct usb_request *dwc3_gadget_ep_alloc_request(struct usb_ep *ep,
 
         req->epnum      = dep->number;
         req->dep        = dep;
-        req->request.dma = DMA_ADDR_INVALID;
 
         return &req->request;
 }
@@ -822,7 +758,8 @@ static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep, u16 cmd_param,
                  * here and stop, unmap, free and del each of the linked
                  * requests instead of we do now.
                  */
-                dwc3_unmap_buffer_from_dma(req);
+                usb_gadget_unmap_request(&dwc->gadget, &req->request,
+                                req->direction);
                 list_del(&req->list);
                 return ret;
         }
@@ -838,6 +775,9 @@ static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep, u16 cmd_param,
 
 static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
 {
+        struct dwc3             *dwc = dep->dwc;
+        int                     ret;
+
         req->request.actual     = 0;
         req->request.status     = -EINPROGRESS;
         req->direction          = dep->direction;
@@ -855,7 +795,11 @@ static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
          * This will also avoid Host cancelling URBs due to too
          * many NACKs.
          */
-        dwc3_map_buffer_to_dma(req);
+        ret = usb_gadget_map_request(&dwc->gadget, &req->request,
+                        dep->direction);
+        if (ret)
+                return ret;
+
         list_add_tail(&req->list, &dep->request_list);
 
         /*
@@ -2150,9 +2094,8 @@ int __devinit dwc3_gadget_init(struct dwc3 *dwc)
                 goto err1;
         }
 
-        dwc->setup_buf = dma_alloc_coherent(dwc->dev,
-                        sizeof(*dwc->setup_buf) * 2,
-                        &dwc->setup_buf_addr, GFP_KERNEL);
+        dwc->setup_buf = kzalloc(sizeof(*dwc->setup_buf) * 2,
+                        GFP_KERNEL);
         if (!dwc->setup_buf) {
                 dev_err(dwc->dev, "failed to allocate setup buffer\n");
                 ret = -ENOMEM;
@@ -2243,8 +2186,7 @@ err4:
                         dwc->ep0_bounce_addr);
 
 err3:
-        dma_free_coherent(dwc->dev, sizeof(*dwc->setup_buf) * 2,
-                        dwc->setup_buf, dwc->setup_buf_addr);
+        kfree(dwc->setup_buf);
 
 err2:
         dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
@@ -2273,8 +2215,7 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
         dma_free_coherent(dwc->dev, 512, dwc->ep0_bounce,
                         dwc->ep0_bounce_addr);
 
-        dma_free_coherent(dwc->dev, sizeof(*dwc->setup_buf) * 2,
-                        dwc->setup_buf, dwc->setup_buf_addr);
+        kfree(dwc->setup_buf);
 
         dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
                         dwc->ep0_trb, dwc->ep0_trb_addr);
diff --git a/drivers/usb/dwc3/gadget.h b/drivers/usb/dwc3/gadget.h
index d97f467d41cc..12f1e104977f 100644
--- a/drivers/usb/dwc3/gadget.h
+++ b/drivers/usb/dwc3/gadget.h
@@ -108,8 +108,6 @@ int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
 int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value);
 int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
                 unsigned cmd, struct dwc3_gadget_ep_cmd_params *params);
-void dwc3_map_buffer_to_dma(struct dwc3_request *req);
-void dwc3_unmap_buffer_from_dma(struct dwc3_request *req);
 
 /**
  * dwc3_gadget_ep_get_transfer_index - Gets transfer index from HW