From: swarren@wwwdotorg•org (Stephen Warren)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH] pinctrl: Add SPEAr pinctrl drivers
Date: Tue, 03 Apr 2012 16:43:39 -0600 [thread overview]
Message-ID: <4F7B7D1B.7030507@wwwdotorg.org> (raw)
In-Reply-To: <CACRpkdZYccTvHEMa=4=-uoLZYQxEPS+932UPA7MGc+-94eLc6w@mail.gmail.com>
On 04/03/2012 03:24 PM, Linus Walleij wrote:
> On Tue, Apr 3, 2012 at 3:47 PM, Arnd Bergmann <arnd@arndb•de> wrote:
>
>> The initialization order dependencies can now be handled using
>> the deferred probe mechanism, by returning -EPROBE_DEFER from
>> the probe() function of any driver that is loaded before its
>> pins are available.
>
> So how do I as a driver writer do that?
>
> Example: drivers/tty/serial/sirfsoc_uart.c:
>
> #include <linux/pinctrl/consumer.h>
>
> probe() {
> if (sirfport->hw_flow_ctrl) {
> sirfport->p = pinctrl_get_select_default(&pdev->dev);
> ret = IS_ERR(sirfport->p);
> if (ret)
> goto pin_err;
> }
>
> pin_err:
> (...)
> return ret;
>
> So basically the pinctrl subsystem needs to return -EPROBE_DEFER
> to the driver in this case, so it can escalate that further.
Yes, I believe so.
There should be a couple of comments in pinctrl now (well, perhaps some
of them aren't there yet until my DT patches are applied!) that indicate
where -EPROBE_DEFER should be returned.
next prev parent reply other threads:[~2012-04-03 22:43 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <a1b7f612544a09989cec80a0318f35b6e48eb1d3.1333453148.git.viresh.kumar@st.com>
2012-04-03 13:47 ` [PATCH] pinctrl: Add SPEAr pinctrl drivers Arnd Bergmann
2012-04-03 14:10 ` viresh kumar
2012-04-03 17:09 ` viresh kumar
2012-04-03 19:33 ` Arnd Bergmann
2012-04-04 4:14 ` Viresh Kumar
2012-04-03 16:19 ` Stephen Warren
2012-04-03 19:37 ` Arnd Bergmann
2012-04-03 21:24 ` Linus Walleij
2012-04-03 22:43 ` Stephen Warren [this message]
2012-04-10 7:54 ` Linus Walleij
2012-04-04 7:45 ` Arnd Bergmann
2012-04-03 21:18 ` Linus Walleij
2012-04-04 4:17 ` Viresh Kumar
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