From: Linus Walleij <linus.walleij@linaro.org>
To: Wang YanQing <udknight@gmail.com>,
Greg KH <gregkh@linuxfoundation.org>,
Linus Walleij <linus.walleij@linaro.org>,
Johan Hovold <jhovold@gmail.com>,
"linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
andi@lisas.de, dforsi@gmail.com
Subject: Re: [PATCH v3] usb:serial:pl2303: add GPIOs interface on PL2303
Date: Wed, 23 Jul 2014 16:59:22 +0200 [thread overview]
Message-ID: <CACRpkdYUkTWxzqX0AqvEUcCNVtbMeg=zmYDWd5fe3-SRnSTs8Q@mail.gmail.com> (raw)
In-Reply-To: <20140721024624.GA25469@udknight>
On Mon, Jul 21, 2014 at 4:46 AM, Wang YanQing <udknight@gmail.com> wrote:
> PL2303HX has two GPIOs, this patch add interface for it.
>
> Signed-off-by: Wang YanQing <udknight@gmail.com>
> ---
> Changes v2-v3:
> 1: fix errors and warnings reported by Daniele Forsi checked with checkpatch.pl
> 2: fix missing GPIOLIB dependence in Kconfig
> 3: fix pl2303_gpio_get can't work
>
> Known issue:
> If gpios are in use(export to userspace through sysfs interface, etc),
> then call pl2303_release(unplug usb-serial convertor, modprobe -r, etc),
> will cause trouble, so we need to make sure there is no gpio user before
> call pl2303_release.
The sysfs ABI is not sound, using it is a recipe for trouble.
IIRC it was merged at a time when drivers/gpio was unmaintained :-(
(...)
> +static struct gpio_chip template_chip = {
> + .label = "pl2303-gpio",
> + .owner = THIS_MODULE,
> + .direction_input = pl2303_gpio_direction_in,
> + .get = pl2303_gpio_get,
> + .direction_output = pl2303_gpio_direction_out,
> + .set = pl2303_gpio_set,
> + .can_sleep = 1,
This is a bool so use = true,
> +#ifdef CONFIG_USB_SERIAL_PL2303_GPIO
> + if (spriv && spriv->gpio) {
> + if (gpiochip_remove(&spriv->gpio->gpio_chip))
> + dev_err(&serial->interface->dev,
> + "unable to remove gpio_chip?\n");
I'm getting rid of the return code from gpiochip_remove() and have removed
the __must_check tag in the gpio tree, so just call gpiochip_remove()
unconditionally and ignore any compile error messages for now.
Yours,
Linus Walleij
prev parent reply other threads:[~2014-07-23 15:06 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-21 2:46 [PATCH v3] usb:serial:pl2303: add GPIOs interface on PL2303 Wang YanQing
2014-07-21 5:46 ` Andreas Mohr
2014-07-21 11:03 ` Wang YanQing
2014-07-23 14:59 ` Linus Walleij [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CACRpkdYUkTWxzqX0AqvEUcCNVtbMeg=zmYDWd5fe3-SRnSTs8Q@mail.gmail.com' \
--to=linus.walleij@linaro.org \
--cc=andi@lisas.de \
--cc=dforsi@gmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=jhovold@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=udknight@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).