Current gadget Tx path always programs DMA in mode-1 if request length is more than packet size. As system DMA can work only in mode-0 so updating the DMA mode and transfer length for it.
Also fixed an issue in device Tx completion path where 'is_dma' is getting set unconditionally. This would fail the io if Tx transfer is done in mode-0. Fixed it by updating it based on 'request->actual' length. Signed-off-by: Ajay Kumar Gupta <[email protected]> --- drivers/usb/musb/musb_gadget.c | 21 ++++++++++++++++++++- 1 files changed, 20 insertions(+), 1 deletions(-) diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c index 6fca870..9ac45e4 100644 --- a/drivers/usb/musb/musb_gadget.c +++ b/drivers/usb/musb/musb_gadget.c @@ -317,6 +317,22 @@ static void txstate(struct musb *musb, struct musb_request *req) else musb_ep->dma->desired_mode = 1; + /* + * Use system dma for unaligned buffers on RTL >= 1.8 + * for Inventra DMA. As system DMA can work only in + * mode-0 so update the desired_mode and request_size. + */ + if (is_inventra_dma_enabled() && + ((request->dma + request->actual) & 0x3) && + (musb->hwvers >= MUSB_HWVERS_1800)) { + + request_size = min_t(size_t, + musb_ep->hw_ep->max_packet_sz_tx, + request->length - request->actual); + + musb_ep->dma->desired_mode = 0; + } + use_dma = use_dma && c->channel_program( musb_ep->dma, musb_ep->packet_sz, musb_ep->dma->desired_mode, @@ -463,7 +479,6 @@ void musb_g_tx(struct musb *musb, u8 epnum) u8 is_dma = 0; if (dma && (csr & MUSB_TXCSR_DMAENAB)) { - is_dma = 1; csr |= MUSB_TXCSR_P_WZC_BITS; csr &= ~(MUSB_TXCSR_DMAENAB | MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY); @@ -471,6 +486,10 @@ void musb_g_tx(struct musb *musb, u8 epnum) /* Ensure writebuffer is empty. */ csr = musb_readw(epio, MUSB_TXCSR); request->actual += musb_ep->dma->actual_len; + + if (request->actual == request->length) + is_dma = 1; + DBG(4, "TXCSR%d %04x, DMA off, len %zu, req %p\n", epnum, csr, musb_ep->dma->actual_len, request); } -- 1.6.2.4 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
