From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754487AbaI1QnE (ORCPT ); Sun, 28 Sep 2014 12:43:04 -0400 Received: from mga02.intel.com ([134.134.136.20]:53513 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752633AbaI1QnB (ORCPT ); Sun, 28 Sep 2014 12:43:01 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,615,1406617200"; d="scan'208";a="609917834" Date: Sun, 28 Sep 2014 21:43:33 +0530 From: Vinod Koul To: Maxime Ripard Cc: dmaengine@vger.kernel.org, Laurent Pinchart , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Antoine =?iso-8859-1?Q?T=E9nart?= , lars@metafoo.de Subject: Re: [PATCH 3/9] dmaengine: Introduce a device_config callback Message-ID: <20140928161333.GK1638@intel.com> References: <1411808085-27792-1-git-send-email-maxime.ripard@free-electrons.com> <1411808085-27792-4-git-send-email-maxime.ripard@free-electrons.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1411808085-27792-4-git-send-email-maxime.ripard@free-electrons.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Sep 27, 2014 at 10:54:39AM +0200, Maxime Ripard wrote: > The fact that the channel configuration is done in device_control is rather > misleading, since it's not really advertised as such, plus, the fact that the > framework exposes a function of its own makes it not really intuitive, while > we're losing the type checking whenever we pass that unsigned long argument. > > Add a device_config callback to dma_device, with a fallback on the old > behaviour for now for existing drivers to opt in. This will break bisect, we have users of device_control in tree, they need to be converted first to use wrappers and then we should introduce these -- ~Vinod > > Signed-off-by: Maxime Ripard > --- > include/linux/dmaengine.h | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h > index f4b71ce1a0a6..7937f81e5e2e 100644 > --- a/include/linux/dmaengine.h > +++ b/include/linux/dmaengine.h > @@ -608,6 +608,8 @@ struct dma_tx_state { > * The function takes a buffer of size buf_len. The callback function will > * be called after period_len bytes have been transferred. > * @device_prep_interleaved_dma: Transfer expression in a generic way. > + * @device_config: Pushes a new configuration to a channel, return 0 or an error > + * code > * @device_control: manipulate all pending operations on a channel, returns > * zero or error code > * @device_tx_status: poll for transaction completion, the optional > @@ -662,7 +664,6 @@ struct dma_device { > struct scatterlist *dst_sg, unsigned int dst_nents, > struct scatterlist *src_sg, unsigned int src_nents, > unsigned long flags); > - > struct dma_async_tx_descriptor *(*device_prep_slave_sg)( > struct dma_chan *chan, struct scatterlist *sgl, > unsigned int sg_len, enum dma_transfer_direction direction, > @@ -674,9 +675,11 @@ struct dma_device { > struct dma_async_tx_descriptor *(*device_prep_interleaved_dma)( > struct dma_chan *chan, struct dma_interleaved_template *xt, > unsigned long flags); > - int (*device_control)(struct dma_chan *chan, enum dma_ctrl_cmd cmd, > - unsigned long arg); > > + int (*device_config)(struct dma_chan *chan, > + struct dma_slave_config *config); > + int (*device_control)(struct dma_chan *chan, enum dma_ctrl_cmd cmd, > + unsigned long arg); > enum dma_status (*device_tx_status)(struct dma_chan *chan, > dma_cookie_t cookie, > struct dma_tx_state *txstate); > @@ -697,6 +700,9 @@ static inline int dmaengine_device_control(struct dma_chan *chan, > static inline int dmaengine_slave_config(struct dma_chan *chan, > struct dma_slave_config *config) > { > + if (chan->device->device_config) > + return chan->device->device_config(chan, config); > + > return dmaengine_device_control(chan, DMA_SLAVE_CONFIG, > (unsigned long)config); > } > -- > 2.1.0 > --