Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752355AbdHPOvg (ORCPT ); Wed, 16 Aug 2017 10:51:36 -0400 Received: from mail-pg0-f68.google.com ([74.125.83.68]:35226 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751530AbdHPOve (ORCPT ); Wed, 16 Aug 2017 10:51:34 -0400 MIME-Version: 1.0 In-Reply-To: <20170718102339.28726-2-wsa+renesas@sang-engineering.com> References: <20170718102339.28726-1-wsa+renesas@sang-engineering.com> <20170718102339.28726-2-wsa+renesas@sang-engineering.com> From: Geert Uytterhoeven Date: Wed, 16 Aug 2017 16:51:33 +0200 X-Google-Sender-Auth: JUQJzPilsgTGR-3VealaY2O0KGw Message-ID: Subject: Re: [PATCH v3 1/4] i2c: add helpers to ease DMA handling To: Wolfram Sang Cc: Linux I2C , Linux-Renesas , Linux Media Mailing List , "linux-input@vger.kernel.org" , linux-iio@vger.kernel.org, ALSA Development Mailing List , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1822 Lines: 56 Hi Wolfram, On Tue, Jul 18, 2017 at 12:23 PM, Wolfram Sang wrote: > One helper checks if DMA is suitable and optionally creates a bounce > buffer, if not. The other function returns the bounce buffer and makes > sure the data is properly copied back to the message. > > Signed-off-by: Wolfram Sang > --- > Changes since v2: > > * rebased to v4.13-rc1 > * helper functions are not inlined anymore but moved to i2c core > * __must_check has been added to the buffer check helper > * the release function has been renamed to contain 'dma' as well Right: drivers/i2c/i2c-core-base.c:2310:15: error: 'i2c_release_bounce_buf' undeclared here (not in a function) EXPORT_SYMBOL_GPL(i2c_release_bounce_buf); > --- a/drivers/i2c/i2c-core-base.c > +++ b/drivers/i2c/i2c-core-base.c > +/** > + * i2c_release_bounce_buf - copy data back from bounce buffer and release it ^^^^^^^^^^^^^^^^^^^^^^ > + * @msg: the message to be copied back to > + * @bounce_buf: the bounce buffer obtained from i2c_check_msg_for_dma(). > + * May be NULL. > + */ > +void i2c_release_dma_bounce_buf(struct i2c_msg *msg, u8 *bounce_buf) > +{ > + if (!bounce_buf) > + return; > + > + if (msg->flags & I2C_M_RD) > + memcpy(msg->buf, bounce_buf, msg->len); > + > + kfree(bounce_buf); > +} > +EXPORT_SYMBOL_GPL(i2c_release_bounce_buf); ^^^^^^^^^^^^^^^^^^^^^^ Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds