Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932835AbcDHAZH (ORCPT ); Thu, 7 Apr 2016 20:25:07 -0400 Received: from mail-pf0-f178.google.com ([209.85.192.178]:36744 "EHLO mail-pf0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932264AbcDHAZC (ORCPT ); Thu, 7 Apr 2016 20:25:02 -0400 Subject: Re: [PATCH v1 07/12] serial: 8250_dma: adjust DMA address of the UART To: Andy Shevchenko References: <1460061433-63750-1-git-send-email-andriy.shevchenko@linux.intel.com> <1460061433-63750-8-git-send-email-andriy.shevchenko@linux.intel.com> Cc: Vinod Koul , linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org, Greg Kroah-Hartman , ismo.puustinen@intel.com, Heikki Krogerus , linux-serial@vger.kernel.org From: Peter Hurley Message-ID: <5706FA5B.8050503@hurleysoftware.com> Date: Thu, 7 Apr 2016 17:24:59 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <1460061433-63750-8-git-send-email-andriy.shevchenko@linux.intel.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1913 Lines: 53 On 04/07/2016 01:37 PM, Andy Shevchenko wrote: > Some UARTs, e.g. one is used in Intel Quark, have a different address base for > DMA operations. Introduce an additional field in struct uart_8250_dma to cover > those cases. > > Signed-off-by: Andy Shevchenko > --- > drivers/tty/serial/8250/8250.h | 2 ++ > drivers/tty/serial/8250/8250_dma.c | 5 +++-- > 2 files changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h > index 047a7ba..040deb2 100644 > --- a/drivers/tty/serial/8250/8250.h > +++ b/drivers/tty/serial/8250/8250.h > @@ -31,6 +31,8 @@ struct uart_8250_dma { > struct dma_chan *rxchan; > struct dma_chan *txchan; > > + phys_addr_t dma_addr; > + Let's add separate rx and tx device addrs. > dma_addr_t rx_addr; > dma_addr_t tx_addr; > > diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c > index b134bec..a314492 100644 > --- a/drivers/tty/serial/8250/8250_dma.c > +++ b/drivers/tty/serial/8250/8250_dma.c > @@ -164,16 +164,17 @@ int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir) > int serial8250_request_dma(struct uart_8250_port *p) > { > struct uart_8250_dma *dma = p->dma; > + phys_addr_t dma_addr = dma->dma_addr ? dma->dma_addr : p->port.mapbase; > dma_cap_mask_t mask; > > /* Default slave configuration parameters */ > dma->rxconf.direction = DMA_DEV_TO_MEM; > dma->rxconf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; > - dma->rxconf.src_addr = p->port.mapbase + UART_RX; > + dma->rxconf.src_addr = dma_addr + UART_RX; > > dma->txconf.direction = DMA_MEM_TO_DEV; > dma->txconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; > - dma->txconf.dst_addr = p->port.mapbase + UART_TX; > + dma->txconf.dst_addr = dma_addr + UART_TX; > > dma_cap_zero(mask); > dma_cap_set(DMA_SLAVE, mask); >