[PATCH 6/7] rtc: sa1100: enable clk support

[Haojian Zhuang]

On Wed, Feb 22, 2012 at 8:29 PM, Arnd Bergmann <arnd at arndb.de> wrote:
> On Tuesday 21 February 2012, Haojian Zhuang wrote:
>> @@ -306,6 +308,13 @@ static int sa1100_rtc_probe(struct platform_device *pdev)
>>         if (!info)
>>                 return -ENOMEM;
>>
>> +       info->clk = clk_get(&pdev->dev, NULL);
>> +       if (IS_ERR(info->clk)) {
>> +               dev_err(&pdev->dev, "failed to find rtc clock source\n");
>> +               ret = PTR_ERR(info->clk);
>> +               goto err_clk;
>> +       }
>> +       clk_prepare_enable(info->clk);
>>         info->iobase = res->start;
>>         info->iosize = resource_size(res);
>>         info->irq_1hz = irq_1hz;
>> @@ -379,6 +388,9 @@ err_dev:
>>         iounmap(info->reg_base);
>>  err_map:
>>         platform_set_drvdata(pdev, NULL);
>> +       clk_disable_unprepare(info->clk);
>> +       clk_put(info->clk);
>> +err_clk:
>>         kfree(info);
>>         return ret;
>
> I wonder whether it would be easier to just make the clk handling
> conditional here, like
>
>        info->clk = clk_get(&pdev->dev, NULL);
>        if (PTR_ERR(info->clk) == -ENOENT)
>                info->clk = NULL;
>        if (IS_ERR(info->clk)) {
>                ret =  PTR_ERR(info->clk);
>                goto err_clk;
>        }
>
>        if (info->clk)
>                clk_prepare_enable(info->clk);
>        ...
>        if (info->clk) {
>                clk_disable_unprepare(info->clk);
>                clk_put(info->clk);
>        }
>
> With this, you would no longer need to add dummy clocks in platforms
> that really have no clock handling.
>
>        Arnd

It sounds good. I'll update it.

Thanks
Haojian