[RFC PATCH 2/2] usb: Example for how to use device node at usb device driver
Peter Chen
hzpeterchen at gmail.com
Sat Jan 9 00:57:56 PST 2016
On Fri, Jan 08, 2016 at 09:26:10AM +0100, Arnd Bergmann wrote:
> On Friday 08 January 2016 13:44:24 Peter Chen wrote:
> > + u32 duration_us = 0;
>
> > + of_property_read_u32(hdev->dev.of_node, "delay-duration-us", &duration_us);
> > + if (duration_us > 0) {
> > + usleep_range(duration_us, duration_us + 10);
> > + dev_info(&hdev->dev, "The delay is %d us\n", duration_us);
> > + }
> > +
>
> I think especially for an example, it would be better to use error checking and
> not initialize the variable:
>
> u32 duration_us;
> int ret;
> ...
> ret = of_property_read_u32(hdev->dev.of_node, "delay-duration-us", &duration_us);
> if (!ret && duration_us > 0) {
> ...
> }
>
> The effect is the same as the other one.
>
Thanks, will change.
--
Best Regards,
Peter Chen
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