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Subject: [Discussion] Uninitialized variable in wiz_mode_select()
From:   Muhammad Usama Anjum <musamaanjum@gmail.com>
To:     Kishon Vijay Abraham I <kishon@ti.com>,
        Vinod Koul <vkoul@kernel.org>,
        "open list:GENERIC PHY FRAMEWORK" <linux-phy@lists.infradead.org>,
        open list <linux-kernel@vger.kernel.org>,
        kernel-janitors@vger.kernel.org, colin.king@canonical.com,
        dan.carpenter@oracle.com
Cc:     musamaanjum@gmail.com
Date:   Thu, 01 Apr 2021 12:33:46 +0500
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Hi,

`mode` remains uninitialized when `lane_phy_type` isn't PHY_TYPE_DP
or 
PHY_TYPE_QSGMII. I've checked the dtsi (k3-j721e-common-proc-
board.dts) 
and possible values of `lane_phy_type` are justPHY_TYPE_USB3 and 
PHY_TYPE_PCIE. If this is correct, the mode will remain uninitialized with
garbage value. `mode` should be initialized to what? It seems like it is highly 
implementation dependent.

/drivers/phy/ti/phy-j721e-wiz.c: 344 in wiz_mode_select()
338             for (i = 0; i < num_lanes; i++) {
339                     if (wiz->lane_phy_type[i] == PHY_TYPE_DP)
340                             mode = LANE_MODE_GEN1;
341                     else if (wiz->lane_phy_type[i] == PHY_TYPE_QSGMII)
342                             mode = LANE_MODE_GEN2;
343     
>>>     CID 1503592:  Uninitialized variables  (UNINIT)
>>>     Using uninitialized value "mode" when calling "regmap_field_write".
344                     ret = regmap_field_write(wiz->p_standard_mode[i], mode);
345                     if (ret)
346                             return ret;
347             }
348     
349             return 0;

Thanks,
Usama