[PATCH v4 3/3] media: ov7670: Add the s_power operation

Hi Wenyou,

On Mon, Sep 18, 2017 at 05:26:16PM +0800, Yang, Wenyou wrote:

Hi Sakari,


On 2017/9/18 15:35, Sakari Ailus wrote:

quoted

Hi Wenyou,

Thanks for the update.

The driver exposes controls that are accessible through the sub-device node
even if the device hasn't been powered on.

Many ISP and bridge drivers will also power the sensor down once the last
user of the user space device nodes disappears. You could keep the device
powered at all times or change the behaviour so that controls can be
accessed when the power is off.

The best option would be to convert the driver to use runtime PM.

Yes, I agree with you.
I also noticed there are a lot of things needed to improve except for it,
such as the platform data via device tree.
I would like do it in another patch set. I will continue to work on it.

Adding runtime PM support later on sound good to me.

quoted

An example of this can be found in drivers/media/i2c/ov13858.c .

A good example, thank you for your providing.

-- 
Sakari Ailus
e-mail: sakari.ailus at iki.fi