From patchwork Fri Aug 12 16:01:47 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Shevchenko X-Patchwork-Id: 9277345 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 480F6600CB for ; Fri, 12 Aug 2016 16:04:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 383AA28A82 for ; Fri, 12 Aug 2016 16:04:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2B94128A86; Fri, 12 Aug 2016 16:04:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CA99928A82 for ; Fri, 12 Aug 2016 16:04:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753081AbcHLQEJ (ORCPT ); Fri, 12 Aug 2016 12:04:09 -0400 Received: from mga03.intel.com ([134.134.136.65]:14295 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753060AbcHLQEH (ORCPT ); Fri, 12 Aug 2016 12:04:07 -0400 Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga103.jf.intel.com with ESMTP; 12 Aug 2016 09:03:39 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,511,1464678000"; d="scan'208";a="864410436" Received: from black.fi.intel.com ([10.237.72.93]) by orsmga003.jf.intel.com with ESMTP; 12 Aug 2016 09:01:57 -0700 Received: by black.fi.intel.com (Postfix, from userid 1003) id E8443284; Fri, 12 Aug 2016 19:01:56 +0300 (EEST) From: Andy Shevchenko To: Bryan O'Donoghue , Peter Hurley , linux-serial@vger.kernel.org, Vinod Koul , linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org, Greg Kroah-Hartman , ismo.puustinen@intel.com, Heikki Krogerus , Eugeniy Paltsev Cc: Andy Shevchenko Subject: [PATCH v10 02/11] dmaengine: dw: set polarity of handshake interface Date: Fri, 12 Aug 2016 19:01:47 +0300 Message-Id: <1471017716-44893-3-git-send-email-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.8.1 In-Reply-To: <1471017716-44893-1-git-send-email-andriy.shevchenko@linux.intel.com> References: <1471017716-44893-1-git-send-email-andriy.shevchenko@linux.intel.com> Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Intel Quark UART uses DesignWare DMA IP. Though the DMA IP is connected in such way that handshake interface uses inverted polarity. We have to provide a possibility to set this in the DMA driver when configuring a channel. Introduce a new member of custom slave configuration called 'hs_polarity' and set active low polarity in case this value is 'true'. Acked-by: Vinod Koul Signed-off-by: Andy Shevchenko --- drivers/dma/dw/core.c | 4 ++++ include/linux/platform_data/dma-dw.h | 2 ++ 2 files changed, 6 insertions(+) diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index 81b06df..80e7421 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -143,6 +143,7 @@ static void dwc_initialize(struct dw_dma_chan *dwc) struct dw_dma *dw = to_dw_dma(dwc->chan.device); u32 cfghi = DWC_CFGH_FIFO_MODE; u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority); + bool hs_polarity = dwc->dws.hs_polarity; if (test_bit(DW_DMA_IS_INITIALIZED, &dwc->flags)) return; @@ -150,6 +151,9 @@ static void dwc_initialize(struct dw_dma_chan *dwc) cfghi |= DWC_CFGH_DST_PER(dwc->dws.dst_id); cfghi |= DWC_CFGH_SRC_PER(dwc->dws.src_id); + /* Set polarity of handshake interface */ + cfglo |= hs_polarity ? DWC_CFGL_HS_DST_POL | DWC_CFGL_HS_SRC_POL : 0; + channel_writel(dwc, CFG_LO, cfglo); channel_writel(dwc, CFG_HI, cfghi); diff --git a/include/linux/platform_data/dma-dw.h b/include/linux/platform_data/dma-dw.h index d15d8ba..4636c93 100644 --- a/include/linux/platform_data/dma-dw.h +++ b/include/linux/platform_data/dma-dw.h @@ -23,6 +23,7 @@ * @dst_id: dst request line * @m_master: memory master for transfers on allocated channel * @p_master: peripheral master for transfers on allocated channel + * @hs_polarity:set active low polarity of handshake interface */ struct dw_dma_slave { struct device *dma_dev; @@ -30,6 +31,7 @@ struct dw_dma_slave { u8 dst_id; u8 m_master; u8 p_master; + bool hs_polarity; }; /**