linux-kernel - Re: [Patch v9 2/3] usb: dwc3: Add Qualcomm DWC3 glue layer driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <541356CE.1020902@smartplayin.com>
Date:	Sat, 13 Sep 2014 01:55:50 +0530
From:	Pramod Gurav <pramod.gurav@...rtplayin.com>
To:	balbi@...com, Pramod Gurav <pramod.gurav.etc@...il.com>
CC:	Andy Gross <agross@...eaurora.org>,
	"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	Kishon Vijay Abraham I <kishon@...com>,
	Jack Pham <jackp@...eaurora.org>,
	Kumar Gala <galak@...eaurora.org>,
	linux-arm-msm <linux-arm-msm@...r.kernel.org>,
	linux-usb@...r.kernel.org, "Ivan T. Ivanov" <iivanov@...sol.com>,
	Bjorn Andersson <bjorn.andersson@...ymobile.com>
Subject: Re: [Patch v9 2/3] usb: dwc3: Add Qualcomm DWC3 glue layer driver

Hi Felipe,

On 13-09-2014 01:50 AM, Felipe Balbi wrote:
> On Sat, Sep 13, 2014 at 01:44:25AM +0530, Pramod Gurav wrote:
>> Andy,
>> Couple of minor comments.
>>
>> On Sat, Sep 13, 2014 at 12:58 AM, Andy Gross <agross@...eaurora.org> wrote:
>>
>>> From: "Ivan T. Ivanov" <iivanov@...sol.com>
>>>
>>> DWC3 glue layer is hardware layer around Synopsys DesignWare
>>> USB3 core. Its purpose is to supply Synopsys IP with required
>>> clocks, voltages and interface it with the rest of the SoC.
>>>
>>> Signed-off-by: Ivan T. Ivanov <iivanov@...sol.com>
>>> Signed-off-by: Andy Gross <agross@...eaurora.org>
>>> ---
>>>  drivers/usb/dwc3/Kconfig     |    8 +++
>>>  drivers/usb/dwc3/Makefile    |    1 +
>>>  drivers/usb/dwc3/dwc3-qcom.c |  131
>>> ++++++++++++++++++++++++++++++++++++++++++
>>>  3 files changed, 140 insertions(+)
>>>  create mode 100644 drivers/usb/dwc3/dwc3-qcom.c
>>>
>>>
>> <..>
>>
>>
>>> +#include <linux/platform_device.h>
>>> +
>>> +struct dwc3_qcom {
>>> +       struct device           *dev;
>>> +
>>>
>> Extra new line here.
> 
> that's not an issue however.
> 
>>> +       struct clk              *core_clk;
>>> +       struct clk              *iface_clk;
>>> +       struct clk              *sleep_clk;
>>> +};
>>> +
>>> +static int dwc3_qcom_probe(struct platform_device *pdev)
>>> +{
>>> +       struct device_node *node = pdev->dev.of_node;
>>> +       struct dwc3_qcom *qdwc;
>>> +       int ret = 0;
>>>
>> Initialization not required.
> 
> I'll fix this one as I'm already applying this patch.
> 
>>> +
>>> +       qdwc = devm_kzalloc(&pdev->dev, sizeof(*qdwc), GFP_KERNEL);
>>> +       if (!qdwc)
>>> +               return -ENOMEM;
>>> +
>>> +       platform_set_drvdata(pdev, qdwc);
>>> +
>>> +       qdwc->dev = &pdev->dev;
>>> +
>>> +       qdwc->core_clk = devm_clk_get(qdwc->dev, "core");
>>> +       if (IS_ERR(qdwc->core_clk)) {
>>> +               dev_err(qdwc->dev, "failed to get core clock\n");
>>> +               return PTR_ERR(qdwc->core_clk);
>>> +       }
>>> +
>>> +       qdwc->iface_clk = devm_clk_get(qdwc->dev, "iface");
>>> +       if (IS_ERR(qdwc->iface_clk)) {
>>> +               dev_dbg(qdwc->dev, "failed to get optional iface clock\n");
>>> +               qdwc->iface_clk = NULL;
>>> +       }
>>> +
>>> +       qdwc->sleep_clk = devm_clk_get(qdwc->dev, "sleep");
>>> +       if (IS_ERR(qdwc->sleep_clk)) {
>>> +               dev_dbg(qdwc->dev, "failed to get optional sleep clock\n");
>>> +               qdwc->sleep_clk = NULL;
>>> +       }
>>> +
>>> +       ret = clk_prepare_enable(qdwc->core_clk);
>>> +       if (ret) {
>>> +               dev_err(qdwc->dev, "failed to enable core clock\n");
>>> +               goto err_core;
>>> +       }
>>> +
>>> +       ret = clk_prepare_enable(qdwc->iface_clk);
>>>
>> Should not we check if  qdwc->iface_clk is valid?
> 
> read the sources luke.
Now I read that its initialized to NULL in fail case but should we call
prepare_enable at all if its NULL?
> 
>>> +err_clks:
>>> +       clk_disable_unprepare(qdwc->sleep_clk);
>>>
>> IS_ERR check before above statement not needed as we have continued with
>> probe even after failure og devm_clk_get?
> 
> read more carefully, there's a detail which you're missing.
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/