mmc: sunplus: fix return value check of mmc_add_host()

mmc_add_host() may return error, if we ignore its return value,
1. the memory allocated in mmc_alloc_host() will be leaked
2. null-ptr-deref will happen when calling mmc_remove_host()
in remove function spmmc_drv_remove() because deleting not
added device.

Fix this by checking the return value of mmc_add_host(). Moreover,
I fixed the error handling path of spmmc_drv_probe() to clean up.

Fixes: 4e268fed8b18 ("mmc: Add mmc driver for Sunplus SP7021")
Cc: stable@vger.kernel.org
Signed-off-by: Wei Chen <harperchen1110@gmail.com>
Link: https://lore.kernel.org/r/20230622090233.188539-1-harperchen1110@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/sunplus-mmc.c b/drivers/mmc/host/sunplus-mmc.c
index db5e0dc..a55a87f 100644 (file)
--- a/drivers/mmc/host/sunplus-mmc.c
+++ b/drivers/mmc/host/sunplus-mmc.c
@@ -902,7 +902,7 @@ static int spmmc_drv_probe(struct platform_device *pdev)
 
        ret = mmc_of_parse(mmc);
        if (ret)
-               goto probe_free_host;
+               goto clk_disable;
 
        mmc->ops = &spmmc_ops;
        mmc->f_min = SPMMC_MIN_CLK;
@@ -911,7 +911,7 @@ static int spmmc_drv_probe(struct platform_device *pdev)
 
        ret = mmc_regulator_get_supply(mmc);
        if (ret)
-               goto probe_free_host;
+               goto clk_disable;
 
        if (!mmc->ocr_avail)
                mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
@@ -927,9 +927,17 @@ static int spmmc_drv_probe(struct platform_device *pdev)
        host->tuning_info.enable_tuning = 1;
        pm_runtime_set_active(&pdev->dev);
        pm_runtime_enable(&pdev->dev);
-       mmc_add_host(mmc);
+       ret = mmc_add_host(mmc);
+       if (ret)
+               goto pm_disable;
 
-       return ret;
+       return 0;
+
+pm_disable:
+       pm_runtime_disable(&pdev->dev);
+
+clk_disable:
+       clk_disable_unprepare(host->clk);
 
 probe_free_host:
        if (mmc)