Re: [PATCH v4 1/2] i2c: davinci: Add PM Runtime Support

From: Baolin Wang
Date: Tue Sep 12 2017 - 05:14:49 EST


Hi,

On 12 September 2017 at 16:48, Sekhar Nori <nsekhar@xxxxxx> wrote:
> On Tuesday 12 September 2017 07:28 AM, Baolin Wang wrote:
>>> @@ -802,13 +821,24 @@ static int davinci_i2c_probe(struct platform_device *pdev)
>>> dev->clk = devm_clk_get(&pdev->dev, NULL);
>>> if (IS_ERR(dev->clk))
>>> return PTR_ERR(dev->clk);
>>> - clk_prepare_enable(dev->clk);
>
>> You removed clk enable here, I think it can not work if we did not
>> open CONFIG_PM macro. I think you should keep clk enable here, and set
>
> What do you mean by "open CONFIG_PM macro" ?

If you did not open CONFIG_PM macro, then the pm_runtime_xxx() will be
dummy functions, but now the i2c driver can not work since you did not
enable clock, right?

>
>> rpm active by pm_runtime_set_active() before issuing
>> pm_runtime_enable().
>
> Can you explain why you want to do this instead of relying on
> pm_runtime_get_sync() to enable clock?

What I mean is you should compatible whether CONFIG_PM is enabled or not.

--
Baolin.wang
Best Regards