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Subject: Re: [Discussion] Uninitialized variable in wiz_mode_select()
From:   Kishon Vijay Abraham I <kishon@ti.com>
To:     Muhammad Usama Anjum <musamaanjum@gmail.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>
References: <943b92c6ac291726cf0e6bd92e88f2110c14b74c.camel@gmail.com>
 <aaa035d2-95a7-00b3-ef76-1aa61c7f8da9@ti.com>
Message-ID: <0ac860d1-15b5-b314-c694-750db6274aa5@ti.com>
Date:   Thu, 1 Apr 2021 13:09:34 +0530
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Hi,

On 01/04/21 1:08 pm, Kishon Vijay Abraham I wrote:
> Hi Usama,
> 
> On 01/04/21 1:03 pm, Muhammad Usama Anjum wrote:
>> 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;
> 
> I've sent a follow-up patch fixing this.
> http://lor.kernel.org/r/20210331131417.15596-1-kishon@ti.com

Fixed a typo in the link
https://lore.kernel.org/linux-phy/20210331131417.15596-1-kishon@ti.com/

Thanks
Kishon