diff options
Diffstat (limited to 'drivers/usb/core/message.c')
-rw-r--r-- | drivers/usb/core/message.c | 41 |
1 files changed, 27 insertions, 14 deletions
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 25f63f1..b6bd05e 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -18,9 +18,17 @@ #include "hcd.h" /* for usbcore internals */ #include "usb.h" +struct api_context { + struct completion done; + int status; +}; + static void usb_api_blocking_completion(struct urb *urb) { - complete((struct completion *)urb->context); + struct api_context *ctx = urb->context; + + ctx->status = urb->status; + complete(&ctx->done); } @@ -32,20 +40,21 @@ static void usb_api_blocking_completion(struct urb *urb) */ static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length) { - struct completion done; + struct api_context ctx; unsigned long expire; int retval; - int status = urb->status; - init_completion(&done); - urb->context = &done; + init_completion(&ctx.done); + urb->context = &ctx; urb->actual_length = 0; retval = usb_submit_urb(urb, GFP_NOIO); if (unlikely(retval)) goto out; expire = timeout ? msecs_to_jiffies(timeout) : MAX_SCHEDULE_TIMEOUT; - if (!wait_for_completion_timeout(&done, expire)) { + if (!wait_for_completion_timeout(&ctx.done, expire)) { + usb_kill_urb(urb); + retval = (ctx.status == -ENOENT ? -ETIMEDOUT : ctx.status); dev_dbg(&urb->dev->dev, "%s timed out on ep%d%s len=%d/%d\n", @@ -54,11 +63,8 @@ static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length) usb_pipein(urb->pipe) ? "in" : "out", urb->actual_length, urb->transfer_buffer_length); - - usb_kill_urb(urb); - retval = status == -ENOENT ? -ETIMEDOUT : status; } else - retval = status; + retval = ctx.status; out: if (actual_length) *actual_length = urb->actual_length; @@ -411,15 +417,22 @@ int usb_sg_init ( * Some systems need to revert to PIO when DMA is temporarily * unavailable. For their sakes, both transfer_buffer and * transfer_dma are set when possible. However this can only - * work on systems without HIGHMEM, since DMA buffers located - * in high memory are not directly addressable by the CPU for - * PIO ... so when HIGHMEM is in use, transfer_buffer is NULL + * work on systems without: + * + * - HIGHMEM, since DMA buffers located in high memory are + * not directly addressable by the CPU for PIO; + * + * - IOMMU, since dma_map_sg() is allowed to use an IOMMU to + * make virtually discontiguous buffers be "dma-contiguous" + * so that PIO and DMA need diferent numbers of URBs. + * + * So when HIGHMEM or IOMMU are in use, transfer_buffer is NULL * to prevent stale pointers and to help spot bugs. */ if (dma) { io->urbs [i]->transfer_dma = sg_dma_address (sg + i); len = sg_dma_len (sg + i); -#ifdef CONFIG_HIGHMEM +#if defined(CONFIG_HIGHMEM) || defined(CONFIG_IOMMU) io->urbs[i]->transfer_buffer = NULL; #else io->urbs[i]->transfer_buffer = |