Hello Tony Huang,
The patch 4e268fed8b18: "mmc: Add mmc driver for Sunplus SP7021" from
Nov 21, 2022, leads to the following Smatch static checker warning
(linux-next):
drivers/mmc/host/sunplus-mmc.c:901 spmmc_drv_probe()
warn: missing unwind goto?
drivers/mmc/host/sunplus-mmc.c
859 static int spmmc_drv_probe(struct platform_device *pdev)
860 {
861 struct mmc_host *mmc;
862 struct resource *res;
863 struct spmmc_host *host;
864 int ret = 0;
865
866 mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
867 if (!mmc) {
868 ret = -ENOMEM;
869 goto probe_free_host;
This would be better as "return -ENOMEM;" but this goto is a no-op.
870 }
871
872 host = mmc_priv(mmc);
873 host->mmc = mmc;
874 host->dmapio_mode = SPMMC_DMA_MODE;
875 host->dma_int_threshold = 1024;
876
877 host->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
878 if (IS_ERR(host->base))
879 return PTR_ERR(host->base);
On the other hand, these should be "goto probe_free_host;"
880
881 host->clk = devm_clk_get(&pdev->dev, NULL);
882 if (IS_ERR(host->clk))
883 return dev_err_probe(&pdev->dev, PTR_ERR(host->clk), "clk get fail\n");
goto
884
885 host->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
886 if (IS_ERR(host->rstc))
887 return dev_err_probe(&pdev->dev, PTR_ERR(host->rstc), "rst get fail\n");
goto
888
889 host->irq = platform_get_irq(pdev, 0);
890 if (host->irq <= 0)
891 return host->irq;
This should be < 0. Otherwise if we are handling impossible situations
we start debating whether to set the error code in the impossible case?
goto
892
893 ret = devm_request_threaded_irq(&pdev->dev, host->irq,
894 spmmc_irq, spmmc_func_finish_req, IRQF_SHARED,
895 NULL, host);
896 if (ret)
897 return ret;
goto
898
899 ret = clk_prepare_enable(host->clk);
900 if (ret)
--> 901 return dev_err_probe(&pdev->dev, ret, "failed to enable clk\n");
goto
902
903 ret = mmc_of_parse(mmc);
904 if (ret)
905 goto clk_disable;
Good!
906
907 mmc->ops = &spmmc_ops;
908 mmc->f_min = SPMMC_MIN_CLK;
909 if (mmc->f_max > SPMMC_MAX_CLK)
910 mmc->f_max = SPMMC_MAX_CLK;
911
912 ret = mmc_regulator_get_supply(mmc);
913 if (ret)
914 goto clk_disable;
915
916 if (!mmc->ocr_avail)
917 mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
918 mmc->max_seg_size = SPMMC_MAX_BLK_COUNT * 512;
919 mmc->max_segs = SPMMC_MAX_DMA_MEMORY_SECTORS;
920 mmc->max_req_size = SPMMC_MAX_BLK_COUNT * 512;
921 mmc->max_blk_size = 512;
922 mmc->max_blk_count = SPMMC_MAX_BLK_COUNT;
923
924 dev_set_drvdata(&pdev->dev, host);
925 spmmc_controller_init(host);
926 spmmc_set_sdmmc_mode(host);
927 host->tuning_info.enable_tuning = 1;
928 pm_runtime_set_active(&pdev->dev);
929 pm_runtime_enable(&pdev->dev);
930 ret = mmc_add_host(mmc);
931 if (ret)
932 goto pm_disable;
933
934 return 0;
935
936 pm_disable:
937 pm_runtime_disable(&pdev->dev);
938
939 clk_disable:
940 clk_disable_unprepare(host->clk);
941
942 probe_free_host:
943 if (mmc)
944 mmc_free_host(mmc);
945
946 return ret;
947 }
regards,
dan carpenter
