Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752249AbaB1CXP (ORCPT ); Thu, 27 Feb 2014 21:23:15 -0500 Received: from va3ehsobe006.messaging.microsoft.com ([216.32.180.16]:41782 "EHLO va3outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751532AbaB1CXO (ORCPT ); Thu, 27 Feb 2014 21:23:14 -0500 X-Forefront-Antispam-Report: CIP:70.37.183.190;KIP:(null);UIP:(null);IPV:NLI;H:mail.freescale.net;RD:none;EFVD:NLI X-SpamScore: -2 X-BigFish: VS-2(zz98dIe0eah1432Izz1f42h2148h208ch1ee6h1de0h1fdah2073h2146h1202h1e76h2189h1d1ah1d2ah21bch1fc6hzzz2dh87h2a8h839h944hd25hf0ah1220h1288h12a5h12a9h12bdh137ah13b6h1441h1504h1537h153bh162dh1631h1758h18e1h1946h19b5h1ad9h1b0ah1b2fh2222h224fh1fb3h1d0ch1d2eh1d3fh1dfeh1dffh1fe8h1ff5h209eh2216h22d0h2336h2438h2461h2487h24ach24d7h2516h2545h255eh25cch1151h1155h) X-FB-DOMAIN-IP-MATCH: fail Date: Fri, 28 Feb 2014 10:23:52 +0800 From: Shawn Guo To: Marek Vasut CC: , , , , , Yuan Yao Subject: Re: [PATCH 1/3] i2c: add DMA support for freescale i2c driver Message-ID: <20140228022348.GB28660@S2101-09.ap.freescale.net> References: <1393481115-22136-1-git-send-email-yao.yuan@freescale.com> <1393481115-22136-2-git-send-email-yao.yuan@freescale.com> <201402272139.36076.marex@denx.de> <20140228021300.GJ13537@S2101-09.ap.freescale.net> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20140228021300.GJ13537@S2101-09.ap.freescale.net> User-Agent: Mutt/1.5.21 (2010-09-15) X-OriginatorOrg: sigmatel.com X-FOPE-CONNECTOR: Id%0$Dn%*$RO%0$TLS%0$FQDN%$TlsDn% X-FOPE-CONNECTOR: Id%0$Dn%FREESCALE.MAIL.ONMICROSOFT.COM$RO%1$TLS%0$FQDN%$TlsDn% Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 28, 2014 at 10:13:02AM +0800, Shawn Guo wrote: > On Thu, Feb 27, 2014 at 09:39:35PM +0100, Marek Vasut wrote: > > > @@ -193,6 +216,7 @@ static const struct imx_i2c_hwdata imx1_i2c_hwdata = { > > > .ndivs = ARRAY_SIZE(imx_i2c_clk_div), > > > .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C, > > > .i2cr_ien_opcode = I2CR_IEN_OPCODE_1, > > > + .has_dma_support = false, > > > > > > }; > > > > > > @@ -203,6 +227,7 @@ static const struct imx_i2c_hwdata imx21_i2c_hwdata = > > > { .ndivs = ARRAY_SIZE(imx_i2c_clk_div), > > > .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C, > > > .i2cr_ien_opcode = I2CR_IEN_OPCODE_1, > > > + .has_dma_support = false, > > > > > > }; > > > > > > @@ -213,6 +238,7 @@ static struct imx_i2c_hwdata vf610_i2c_hwdata = { > > > .ndivs = ARRAY_SIZE(vf610_i2c_clk_div), > > > .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C, > > > .i2cr_ien_opcode = I2CR_IEN_OPCODE_0, > > > + .has_dma_support = true, > > > > So why exactly don't we have a DT prop for determining whether the controller > > has DMA support ? > > Using DMA or PIO is a decision that should be made by driver on its own, > not device tree. Sorry. I misunderstood it. Yes, we can look at the DT property 'dmas' to know if the controller has DMA capability. Shawn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/