diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/musb/musbhsdma.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/usb/musb/musbhsdma.c b/drivers/usb/musb/musbhsdma.c index 6f771af5cbd..563114d613d 100644 --- a/drivers/usb/musb/musbhsdma.c +++ b/drivers/usb/musb/musbhsdma.c @@ -158,6 +158,8 @@ static int dma_channel_program(struct dma_channel *channel, dma_addr_t dma_addr, u32 len) { struct musb_dma_channel *musb_channel = channel->private_data; + struct musb_dma_controller *controller = musb_channel->controller; + struct musb *musb = controller->private_data; DBG(2, "ep%d-%s pkt_sz %d, dma_addr 0x%x length %d, mode %d\n", musb_channel->epnum, @@ -167,6 +169,18 @@ static int dma_channel_program(struct dma_channel *channel, BUG_ON(channel->status == MUSB_DMA_STATUS_UNKNOWN || channel->status == MUSB_DMA_STATUS_BUSY); + /* + * The DMA engine in RTL1.8 and above cannot handle + * DMA addresses that are not aligned to a 4 byte boundary. + * It ends up masking the last two bits of the address + * programmed in DMA_ADDR. + * + * Fail such DMA transfers, so that the backup PIO mode + * can carry out the transfer + */ + if ((musb->hwvers >= MUSB_HWVERS_1800) && (dma_addr % 4)) + return false; + channel->actual_len = 0; musb_channel->start_addr = dma_addr; musb_channel->len = len; |