Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752680AbcDVMpL (ORCPT ); Fri, 22 Apr 2016 08:45:11 -0400 Received: from hqemgate15.nvidia.com ([216.228.121.64]:14967 "EHLO hqemgate15.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751675AbcDVMpJ (ORCPT ); Fri, 22 Apr 2016 08:45:09 -0400 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Fri, 22 Apr 2016 05:44:56 -0700 From: Shardar Shariff Md To: , , , , , , , , , CC: Shardar Shariff Md Subject: [PATCH v2] dmaengine: tegra-apb: proper default init of channel slave_id Date: Fri, 22 Apr 2016 18:14:53 +0530 Message-ID: <1461329093-20300-1-git-send-email-smohammed@nvidia.com> X-Mailer: git-send-email 1.8.1.5 MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2127 Lines: 68 Initialize default channel slave_id(req_sel) to invalid id (i.e max supported slave id + 1) to avoid overwriting of slave_id during tegra_dma_slave_config() with client data if slave_id is not initialized through DT Signed-off-by: Shardar Shariff Md --- - Instead of initializing the slave id to -1 define macros for max slave id and invalid slave id and do the checks accordingly. --- drivers/dma/tegra20-apb-dma.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index 3871f29..2957e26 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -114,6 +114,9 @@ /* Channel base address offset from APBDMA base address */ #define TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET 0x1000 +#define TEGRA_APBDMA_SLAVE_ID_MAX 31 +#define TEGRA_APBDMA_SLAVE_ID_INVALID (TEGRA_APBDMA_SLAVE_ID_MAX + 1) + struct tegra_dma; /* @@ -353,7 +356,7 @@ static int tegra_dma_slave_config(struct dma_chan *dc, } memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig)); - if (!tdc->slave_id) + if (tdc->slave_id == TEGRA_APBDMA_SLAVE_ID_INVALID) tdc->slave_id = sconfig->slave_id; tdc->config_init = true; return 0; @@ -1236,7 +1239,7 @@ static void tegra_dma_free_chan_resources(struct dma_chan *dc) } pm_runtime_put(tdma->dev); - tdc->slave_id = 0; + tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID; } static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec, @@ -1253,6 +1256,11 @@ static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec, tdc = to_tegra_dma_chan(chan); tdc->slave_id = dma_spec->args[0]; + if (tdc->slave_id > TEGRA_APBDMA_SLAVE_ID_MAX) { + dev_err(tdc2dev(tdc), "Invalid slave id\n"); + return NULL; + } + return chan; } @@ -1389,6 +1397,7 @@ static int tegra_dma_probe(struct platform_device *pdev) &tdma->dma_dev.channels); tdc->tdma = tdma; tdc->id = i; + tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID; tasklet_init(&tdc->tasklet, tegra_dma_tasklet, (unsigned long)tdc); -- 1.8.1.5