From: hzpeterchen@gmail.com (Peter Chen)
To: linux-arm-kernel@lists.infradead.org
Subject: [RFC PATCH 2/2] usb: Example for how to use device node at usb device driver
Date: Sat, 9 Jan 2016 16:57:56 +0800 [thread overview]
Message-ID: <20160109085756.GC27759@shlinux2> (raw)
In-Reply-To: <4231421.FQCAATyWeB@wuerfel>
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
prev parent reply other threads:[~2016-01-09 8:57 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-08 5:44 [RFC PATCH 0/2] USB: let the USB device know device node Peter Chen
2016-01-08 5:44 ` [RFC PATCH 1/2] USB: core: let " Peter Chen
2016-01-08 8:22 ` Arnd Bergmann
2016-01-09 8:56 ` Peter Chen
2016-01-08 14:32 ` Rob Herring
2016-01-09 9:05 ` Peter Chen
2016-01-09 15:20 ` Rob Herring
2016-01-08 22:50 ` Alan Stern
2016-01-09 9:32 ` Peter Chen
2016-01-08 5:44 ` [RFC PATCH 2/2] usb: Example for how to use device node at usb device driver Peter Chen
2016-01-08 8:26 ` Arnd Bergmann
2016-01-09 8:57 ` Peter Chen [this message]
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