From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752642AbcDLEbZ (ORCPT ); Tue, 12 Apr 2016 00:31:25 -0400 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:33830 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751181AbcDLEbX (ORCPT ); Tue, 12 Apr 2016 00:31:23 -0400 Date: Tue, 12 Apr 2016 05:31:15 +0100 From: Mark Brown To: Vignesh R Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org Message-ID: <20160412043115.GV3351@sirena.org.uk> References: <1459828192-5531-1-git-send-email-vigneshr@ti.com> <1459828192-5531-2-git-send-email-vigneshr@ti.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="gPQW1Pk7T/0rhUBV" Content-Disposition: inline In-Reply-To: <1459828192-5531-2-git-send-email-vigneshr@ti.com> X-Cookie: I invented skydiving in 1989! User-Agent: Mutt/1.5.24 (2015-08-30) X-SA-Exim-Connect-IP: 2a01:348:6:8808:fab::3 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH 1/2] spi: Add DMA support for spi_flash_read() X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on mezzanine.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --gPQW1Pk7T/0rhUBV Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Apr 05, 2016 at 09:19:51AM +0530, Vignesh R wrote: > mutex_lock(&master->bus_lock_mutex); > + if (master->dma_rx) { > + rx_dev = master->dma_rx->device->dev; > + ret = spi_map_buf(master, rx_dev, &msg->rx_sg, > + msg->buf, msg->len, > + DMA_FROM_DEVICE); > + if (ret != 0) > + goto err; > + } This is unconditionally DMA mapping the buffer if DMA is supported. That's going to be common but I'm not sure it'll be universal, we need to think of something better here. I'm not immediately seeing what though. Possibly a flag... --gPQW1Pk7T/0rhUBV Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJXDHoSAAoJECTWi3JdVIfQ7gUH/iASryu9N/Ltr463xmf0o3+4 F80vdBVApn0n4QzOCzt4nQ5A4drvf+C9neWAFWHFGdHmW9pysx4cRc+FPnsAVc1Q W15QKlqQhxC7KHAr16KScTJuLwT9/EH9WYDMwk+I+a+4OE+COEWJi/XPjwn3Jl6J Fwdppq0PNkNr5DTBi2AOYufErk7WWcJAB8uQ+3Dn+w+PL1CtQ6zQ7iTGJ67MZ9yj cqhZ+gQTsWBrBcePrmEX0NmHp6Y13dzVOAu9v7SjYT3n/0CaAuBtj7ec3yg4FxJF AlPWSMREqe9hZndHQ1ONuYrjw/gQP5TAL1vFrEZRMfBN6zggd2sCSytL56vQtb0= =SQHo -----END PGP SIGNATURE----- --gPQW1Pk7T/0rhUBV--