Re: [PATCH v4 1/1] ARM: davinci: aemif: get rid of davinci-nand driver dependency on aemif

[Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>]

Hi Sekhar,

Do you want me to correct it?

On 01/20/2014 08:44 PM, Brian Norris wrote:
> Hi Sekhar,
>
> Sorry, I do have one complaint about this patch.
>
> On Fri, Jan 10, 2014 at 03:06:04PM +0530, Sekhar Nori wrote:
>> --- a/arch/arm/mach-davinci/aemif.c
>> +++ b/arch/arm/mach-davinci/aemif.c
>> @@ -130,4 +136,82 @@ int davinci_aemif_setup_timing(struct davinci_aemif_timing *t,
>>   
>>   	return 0;
>>   }
>> -EXPORT_SYMBOL(davinci_aemif_setup_timing);
>> +
>> +/**
>> + * davinci_aemif_setup - setup AEMIF interface by davinci_nand_pdata
>> + * @pdev - link to platform device to setup settings for
>> + *
>> + * This function does not use any locking while programming the AEMIF
>> + * because it is expected that there is only one user of a given
>> + * chip-select.
>> + *
>> + * Returns 0 on success, else negative errno.
>> + */
>> +int davinci_aemif_setup(struct platform_device *pdev)
>> +{
>> +	struct davinci_nand_pdata *pdata = dev_get_platdata(&pdev->dev);
>> +	uint32_t val;
>> +	unsigned long clkrate;
>> +	struct resource	*res;
>> +	void __iomem *base;
>> +	struct clk *clk;
>> +	int ret = 0;
>> +
>> +	clk = clk_get(&pdev->dev, "aemif");
>> +	if (IS_ERR(clk)) {
>> +		ret = PTR_ERR(clk);
>> +		dev_dbg(&pdev->dev, "unable to get AEMIF clock, err %d\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	ret = clk_prepare_enable(clk);
>> +	if (ret < 0) {
>> +		dev_dbg(&pdev->dev, "unable to enable AEMIF clock, err %d\n",
>> +			ret);
>> +		return ret;
> coccinelle gives a warning for this:
>
>    arch/arm/mach-davinci/aemif.c:171:2-8: ERROR: missing clk_put; clk_get on line 160 and execution via conditional on line 168 [coccinelle]
>
> You need a clk_put() on the error path for clk_prepare_enable. For
> instance, you can add a label below and replace this 'return ret' with
> 'goto err_put'.
>
>> +	}
>> +
>> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
>> +	if (!res) {
>> +		dev_err(&pdev->dev, "cannot get IORESOURCE_MEM\n");
>> +		ret = -ENOMEM;
>> +		goto err;
>> +	}
>> +
>> +	base = ioremap(res->start, resource_size(res));
>> +	if (!base) {
>> +		dev_err(&pdev->dev, "ioremap failed for resource %pR\n", res);
>> +		ret = -ENOMEM;
>> +		goto err;
>> +	}
>> +
>> +	/*
>> +	 * Setup Async configuration register in case we did not boot
>> +	 * from NAND and so bootloader did not bother to set it up.
>> +	 */
>> +	val = davinci_aemif_readl(base, A1CR_OFFSET + pdev->id * 4);
>> +	/*
>> +	 * Extended Wait is not valid and Select Strobe mode is not
>> +	 * used
>> +	 */
>> +	val &= ~(ACR_ASIZE_MASK | ACR_EW_MASK | ACR_SS_MASK);
>> +	if (pdata->options & NAND_BUSWIDTH_16)
>> +		val |= 0x1;
>> +
>> +	davinci_aemif_writel(base, A1CR_OFFSET + pdev->id * 4, val);
>> +
>> +	clkrate = clk_get_rate(clk);
>> +
>> +	if (pdata->timing)
>> +		ret = davinci_aemif_setup_timing(pdata->timing, base, pdev->id,
>> +						 clkrate);
>> +
>> +	if (ret < 0)
>> +		dev_dbg(&pdev->dev, "NAND timing values setup fail\n");
>> +
>> +	iounmap(base);
>> +err:
>> +	clk_disable_unprepare(clk);
> Then the label could be here:
>
> err_put:
>
>> +	clk_put(clk);
>> +	return ret;
>> +}
> Brian