On 13-12-2023 12:07, Dan Carpenter wrote:
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Hello Mohan Kumar,
The patch 25b636225a08: "dmaengine: tegra210-adma: Support
dma-channel-mask property" from Nov 28, 2023 (linux-next), leads to
the following Smatch static checker warning:
drivers/dma/tegra210-adma.c:887 tegra_adma_probe()
warn: passing casted pointer 'tdma->dma_chan_mask' to 'of_property_read_u32_array()' 64 vs 32.
drivers/dma/tegra210-adma.c
845 static int tegra_adma_probe(struct platform_device *pdev)
846 {
847 const struct tegra_adma_chip_data *cdata;
848 struct tegra_adma *tdma;
849 int ret, i;
850
851 cdata = of_device_get_match_data(&pdev->dev);
852 if (!cdata) {
853 dev_err(&pdev->dev, "device match data not found\n");
854 return -ENODEV;
855 }
856
857 tdma = devm_kzalloc(&pdev->dev,
858 struct_size(tdma, channels, cdata->nr_channels),
859 GFP_KERNEL);
860 if (!tdma)
861 return -ENOMEM;
862
863 tdma->dev = &pdev->dev;
864 tdma->cdata = cdata;
865 tdma->nr_channels = cdata->nr_channels;
866 platform_set_drvdata(pdev, tdma);
867
868 tdma->base_addr = devm_platform_ioremap_resource(pdev, 0);
869 if (IS_ERR(tdma->base_addr))
870 return PTR_ERR(tdma->base_addr);
871
872 tdma->ahub_clk = devm_clk_get(&pdev->dev, "d_audio");
873 if (IS_ERR(tdma->ahub_clk)) {
874 dev_err(&pdev->dev, "Error: Missing ahub controller clock\n");
875 return PTR_ERR(tdma->ahub_clk);
876 }
877
878 tdma->dma_chan_mask = devm_kzalloc(&pdev->dev,
879 BITS_TO_LONGS(tdma->nr_channels) * sizeof(unsigned long),
880 GFP_KERNEL);
881 if (!tdma->dma_chan_mask)
882 return -ENOMEM;
883
884 /* Enable all channels by default */
885 bitmap_fill(tdma->dma_chan_mask, tdma->nr_channels);
886
--> 887 ret = of_property_read_u32_array(pdev->dev.of_node, "dma-channel-mask",
888 (u32 *)tdma->dma_chan_mask,
I don't think this will work on big endian systems... Do we care about
that?
We don't care for big endian, as all the Tegra chip which is supported
by this adma driver is little endian. If you still have any concern we
need to re-look on the typecasting logic.
889 BITS_TO_U32(tdma->nr_channels));
890 if (ret < 0 && (ret != -EINVAL)) {
891 dev_err(&pdev->dev, "dma-channel-mask is not complete.\n");
892 return ret;
893 }
894
895 INIT_LIST_HEAD(&tdma->dma_dev.channels);
896 for (i = 0; i < tdma->nr_channels; i++) {
897 struct tegra_adma_chan *tdc = &tdma->channels[i];
898
899 /* skip for reserved channels */
900 if (!test_bit(i, tdma->dma_chan_mask))
901 continue;
902
regards,
dan carpenter
