linux-kernel - [PATCH 1/2] mmc: moxart: remove unneeded check for drvdata

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Date:   Wed, 23 Sep 2020 17:37:38 +0200
From:   Krzysztof Kozlowski <krzk@...nel.org>
To:     Ulf Hansson <ulf.hansson@...aro.org>,
        Adrian Hunter <adrian.hunter@...el.com>,
        Shawn Guo <shawnguo@...nel.org>,
        Sascha Hauer <s.hauer@...gutronix.de>,
        Pengutronix Kernel Team <kernel@...gutronix.de>,
        Fabio Estevam <festevam@...il.com>,
        NXP Linux Team <linux-imx@....com>,
        Orson Zhai <orsonzhai@...il.com>,
        Baolin Wang <baolin.wang7@...il.com>,
        Chunyan Zhang <zhang.lyra@...il.com>,
        linux-mmc@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org
Cc:     Krzysztof Kozlowski <krzk@...nel.org>
Subject: [PATCH 1/2] mmc: moxart: remove unneeded check for drvdata

The 'struct mmc_host *mmc' comes from drvdata set at the end of probe,
so it cannot be NULL.  The code already dereferences it few lines before
the check with mmc_priv().  This also fixes smatch warning:

  drivers/mmc/host/moxart-mmc.c:692 moxart_remove() warn: variable dereferenced before check 'mmc' (see line 688)

Reported-by: kernel test robot <lkp@...el.com>
Reported-by: Dan Carpenter <dan.carpenter@...cle.com>
Signed-off-by: Krzysztof Kozlowski <krzk@...nel.org>
---
 drivers/mmc/host/moxart-mmc.c | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/mmc/host/moxart-mmc.c b/drivers/mmc/host/moxart-mmc.c
index 2bfb376fddc4..f25079ba3bca 100644
--- a/drivers/mmc/host/moxart-mmc.c
+++ b/drivers/mmc/host/moxart-mmc.c
@@ -689,19 +689,18 @@ static int moxart_remove(struct platform_device *pdev)
 
 	dev_set_drvdata(&pdev->dev, NULL);
 
-	if (mmc) {
-		if (!IS_ERR(host->dma_chan_tx))
-			dma_release_channel(host->dma_chan_tx);
-		if (!IS_ERR(host->dma_chan_rx))
-			dma_release_channel(host->dma_chan_rx);
-		mmc_remove_host(mmc);
-		mmc_free_host(mmc);
+	if (!IS_ERR(host->dma_chan_tx))
+		dma_release_channel(host->dma_chan_tx);
+	if (!IS_ERR(host->dma_chan_rx))
+		dma_release_channel(host->dma_chan_rx);
+	mmc_remove_host(mmc);
+	mmc_free_host(mmc);
+
+	writel(0, host->base + REG_INTERRUPT_MASK);
+	writel(0, host->base + REG_POWER_CONTROL);
+	writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF,
+	       host->base + REG_CLOCK_CONTROL);
 
-		writel(0, host->base + REG_INTERRUPT_MASK);
-		writel(0, host->base + REG_POWER_CONTROL);
-		writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF,
-		       host->base + REG_CLOCK_CONTROL);
-	}
 	return 0;
 }
 
-- 
2.17.1