Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755881AbaJ1VmR (ORCPT ); Tue, 28 Oct 2014 17:42:17 -0400 Received: from down.free-electrons.com ([37.187.137.238]:37100 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932107AbaJ1Vaj (ORCPT ); Tue, 28 Oct 2014 17:30:39 -0400 From: Maxime Ripard To: Vinod Koul , dmaengine@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Laurent Pinchart , =?UTF-8?q?Antoine=20T=C3=A9nart?= , Russell King , lars@metafoo.de, Maxime Ripard Subject: [PATCH v4 05/58] dmaengine: Make channel allocation callbacks optional Date: Tue, 28 Oct 2014 22:25:20 +0100 Message-Id: <1414531573-18807-6-git-send-email-maxime.ripard@free-electrons.com> X-Mailer: git-send-email 2.1.1 In-Reply-To: <1414531573-18807-1-git-send-email-maxime.ripard@free-electrons.com> References: <1414531573-18807-1-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 Nowadays, some drivers don't have anything in there channel allocation callbacks anymore. Remove the BUG_ON if those callbacks aren't implemented, in order to allow drivers to not implement them. Signed-off-by: Maxime Ripard Acked-by: Laurent Pinchart --- drivers/dma/dmaengine.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 72f10e2f5c32..9b2cd74b8f2e 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -235,9 +235,11 @@ static int dma_chan_get(struct dma_chan *chan) return -ENODEV; /* allocate upon first client reference */ - ret = chan->device->device_alloc_chan_resources(chan); - if (ret < 0) - goto err_out; + if (chan->device->device_alloc_chan_resources) { + ret = chan->device->device_alloc_chan_resources(chan); + if (ret < 0) + goto err_out; + } if (!dma_has_cap(DMA_PRIVATE, chan->device->cap_mask)) balance_ref_count(chan); @@ -259,11 +261,15 @@ err_out: */ static void dma_chan_put(struct dma_chan *chan) { + /* This channel is not in use, bail out */ if (!chan->client_count) - return; /* this channel failed alloc_chan_resources */ + return; + chan->client_count--; module_put(dma_chan_to_owner(chan)); - if (chan->client_count == 0) + + /* This channel is not in use anymore, free it */ + if (!chan->client_count && chan->device->device_free_chan_resources) chan->device->device_free_chan_resources(chan); } @@ -819,8 +825,6 @@ int dma_async_device_register(struct dma_device *device) BUG_ON(dma_has_cap(DMA_INTERLEAVE, device->cap_mask) && !device->device_prep_interleaved_dma); - BUG_ON(!device->device_alloc_chan_resources); - BUG_ON(!device->device_free_chan_resources); BUG_ON(!device->device_tx_status); BUG_ON(!device->device_issue_pending); BUG_ON(!device->dev); -- 2.1.1 -- 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/