usb: musb: avoid null pointer dereference in debug logging

[deliverable/linux.git] / drivers / usb / musb / musb_gadget.c

diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c
index 0414bc19d0095258ab5e646858ce342a740f92c8..b7b8b2bc4ee9de02bb7e65cd2245b7e9460af537 100644 (file)
--- a/drivers/usb/musb/musb_gadget.c
+++ b/drivers/usb/musb/musb_gadget.c
@@ -76,13 +76,21 @@ static inline void map_dma_buffer(struct musb_request *request,
                return;
 
        if (request->request.dma == DMA_ADDR_INVALID) {
-               request->request.dma = dma_map_single(
+               dma_addr_t dma_addr;
+               int ret;
+
+               dma_addr = dma_map_single(
                                musb->controller,
                                request->request.buf,
                                request->request.length,
                                request->tx
                                        ? DMA_TO_DEVICE
                                        : DMA_FROM_DEVICE);
+               ret = dma_mapping_error(musb->controller, dma_addr);
+               if (ret)
+                       return;
+
+               request->request.dma = dma_addr;
                request->map_state = MUSB_MAPPED;
        } else {
                dma_sync_single_for_device(musb->controller,
@@ -357,47 +365,49 @@ static void txstate(struct musb *musb, struct musb_request *req)
                        }
                }
 
-#elif defined(CONFIG_USB_TI_CPPI_DMA)
-               /* program endpoint CSR first, then setup DMA */
-               csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
-               csr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_DMAMODE |
-                      MUSB_TXCSR_MODE;
-               musb_writew(epio, MUSB_TXCSR,
-                       (MUSB_TXCSR_P_WZC_BITS & ~MUSB_TXCSR_P_UNDERRUN)
-                               | csr);
-
-               /* ensure writebuffer is empty */
-               csr = musb_readw(epio, MUSB_TXCSR);
-
-               /* NOTE host side sets DMAENAB later than this; both are
-                * OK since the transfer dma glue (between CPPI and Mentor
-                * fifos) just tells CPPI it could start.  Data only moves
-                * to the USB TX fifo when both fifos are ready.
-                */
-
-               /* "mode" is irrelevant here; handle terminating ZLPs like
-                * PIO does, since the hardware RNDIS mode seems unreliable
-                * except for the last-packet-is-already-short case.
-                */
-               use_dma = use_dma && c->channel_program(
-                               musb_ep->dma, musb_ep->packet_sz,
-                               0,
-                               request->dma + request->actual,
-                               request_size);
-               if (!use_dma) {
-                       c->channel_release(musb_ep->dma);
-                       musb_ep->dma = NULL;
-                       csr &= ~MUSB_TXCSR_DMAENAB;
-                       musb_writew(epio, MUSB_TXCSR, csr);
-                       /* invariant: prequest->buf is non-null */
-               }
-#elif defined(CONFIG_USB_TUSB_OMAP_DMA)
-               use_dma = use_dma && c->channel_program(
-                               musb_ep->dma, musb_ep->packet_sz,
-                               request->zero,
-                               request->dma + request->actual,
-                               request_size);
 #endif
+               if (is_cppi_enabled()) {
+                       /* program endpoint CSR first, then setup DMA */
+                       csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
+                       csr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_DMAMODE |
+                               MUSB_TXCSR_MODE;
+                       musb_writew(epio, MUSB_TXCSR, (MUSB_TXCSR_P_WZC_BITS &
+                                               ~MUSB_TXCSR_P_UNDERRUN) | csr);
+
+                       /* ensure writebuffer is empty */
+                       csr = musb_readw(epio, MUSB_TXCSR);
+
+                       /*
+                        * NOTE host side sets DMAENAB later than this; both are
+                        * OK since the transfer dma glue (between CPPI and
+                        * Mentor fifos) just tells CPPI it could start. Data
+                        * only moves to the USB TX fifo when both fifos are
+                        * ready.
+                        */
+                       /*
+                        * "mode" is irrelevant here; handle terminating ZLPs
+                        * like PIO does, since the hardware RNDIS mode seems
+                        * unreliable except for the
+                        * last-packet-is-already-short case.
+                        */
+                       use_dma = use_dma && c->channel_program(
+                                       musb_ep->dma, musb_ep->packet_sz,
+                                       0,
+                                       request->dma + request->actual,
+                                       request_size);
+                       if (!use_dma) {
+                               c->channel_release(musb_ep->dma);
+                               musb_ep->dma = NULL;
+                               csr &= ~MUSB_TXCSR_DMAENAB;
+                               musb_writew(epio, MUSB_TXCSR, csr);
+                               /* invariant: prequest->buf is non-null */
+                       }
+               } else if (tusb_dma_omap())
+                       use_dma = use_dma && c->channel_program(
+                                       musb_ep->dma, musb_ep->packet_sz,
+                                       request->zero,
+                                       request->dma + request->actual,
+                                       request_size);
        }
 #endif
 
@@ -1266,7 +1276,8 @@ static int musb_gadget_queue(struct usb_ep *ep, struct usb_request *req,
                dev_dbg(musb->controller, "req %p queued to %s while ep %s\n",
                                req, ep->name, "disabled");
                status = -ESHUTDOWN;
-               goto cleanup;
+               unmap_dma_buffer(request, musb);
+               goto unlock;
        }
 
        /* add request to the list */
@@ -1276,7 +1287,7 @@ static int musb_gadget_queue(struct usb_ep *ep, struct usb_request *req,
        if (!musb_ep->busy && &request->list == musb_ep->req_list.next)
                musb_ep_restart(musb, request);
 
-cleanup:
+unlock:
        spin_unlock_irqrestore(&musb->lock, lockflags);
        return status;
 }
@@ -1926,7 +1937,8 @@ static int musb_gadget_stop(struct usb_gadget *g,
        stop_activity(musb, driver);
        otg_set_peripheral(musb->xceiv->otg, NULL);
 
-       dev_dbg(musb->controller, "unregistering driver %s\n", driver->function);
+       dev_dbg(musb->controller, "unregistering driver %s\n",
+                                 driver ? driver->function : "(removed)");
 
        musb->is_active = 0;
        musb->gadget_driver = NULL;