From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754474AbaJVPpW (ORCPT ); Wed, 22 Oct 2014 11:45:22 -0400 Received: from down.free-electrons.com ([37.187.137.238]:53968 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754367AbaJVPpQ (ORCPT ); Wed, 22 Oct 2014 11:45:16 -0400 From: Maxime Ripard To: dmaengine@vger.kernel.org, Vinod Koul Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Laurent Pinchart , =?UTF-8?q?Antoine=20T=C3=A9nart?= , lars@metafoo.de, Russell King , Maxime Ripard , Dan Williams Subject: [PATCH v3 10/59] dmaengine: Create a generic dma_slave_caps callback Date: Wed, 22 Oct 2014 17:43:24 +0200 Message-Id: <1413992653-21963-11-git-send-email-maxime.ripard@free-electrons.com> X-Mailer: git-send-email 2.1.1 In-Reply-To: <1413992653-21963-1-git-send-email-maxime.ripard@free-electrons.com> References: <1413992653-21963-1-git-send-email-maxime.ripard@free-electrons.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org dma_slave_caps is very important to the generic layers that might interact with dmaengine, such as ASoC. Unfortunately, it has been added as yet another dma_device callback, and most of the existing drivers haven't implemented it, reducing its reliability. Introduce a generic behaviour and a flag to trigger it. In case this flag hasn't been set, fall back to the old mechanism. Signed-off-by: Maxime Ripard --- include/linux/dmaengine.h | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-) diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index b0efc805937a..6b74d9d8977e 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -642,6 +642,8 @@ struct dma_device { int dev_id; struct device *dev; + bool generic_slave_caps; + int (*device_alloc_chan_resources)(struct dma_chan *chan); void (*device_free_chan_resources)(struct dma_chan *chan); @@ -783,17 +785,32 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_sg( static inline int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps) { + struct dma_device *device; + if (!chan || !caps) return -EINVAL; + device = chan->device; + /* check if the channel supports slave transactions */ - if (!test_bit(DMA_SLAVE, chan->device->cap_mask.bits)) + if (!test_bit(DMA_SLAVE, device->cap_mask.bits)) + return -ENXIO; + + if (device->device_slave_caps) + return device->device_slave_caps(chan, caps); + + /* + * Check whether it reports it uses the generic slave + * capabilities, if not, that means it doesn't support any + * kind of slave capabilities reporting. + */ + if (device->generic_slave_caps) return -ENXIO; - if (chan->device->device_slave_caps) - return chan->device->device_slave_caps(chan, caps); + caps->cmd_pause = !!device->device_pause; + caps->cmd_terminate = !!device->device_terminate_all; - return -ENXIO; + return 0; } static inline int dmaengine_terminate_all(struct dma_chan *chan) -- 2.1.1