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

Brian Norris
2014-01-20T18:44:18Z

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