From: "Rafael J. Wysocki" <rafael@kernel.org>
To: Enrico Granata <egranata@chromium.org>
Cc: Hans de Goede <hdegoede@redhat.com>,
Mika Westerberg <mika.westerberg@linux.intel.com>,
Dmitry Torokhov <dtor@chromium.org>,
Andy Shevchenko <andy.shevchenko@gmail.com>,
"Rafael J. Wysocki" <rafael@kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Enric Balletbo i Serra <enric.balletbo@collabora.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Gwendal Grignou <gwendal@chromium.org>,
ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
Brian Norris <briannorris@chromium.org>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Enrico Granata <egranata@google.com>
Subject: Re: [PATCH v2] driver: platform: Support parsing GpioInt 0 in platform_get_irq()
Date: Sun, 24 Feb 2019 20:34:45 +0100 [thread overview]
Message-ID: <CAJZ5v0g-pWj9Fmg6W4+tt6QQCRssxcjVsHSDedO+ph3jsREhZw@mail.gmail.com> (raw)
In-Reply-To: <20190211190112.209286-1-egranata@chromium.org>
On Mon, Feb 11, 2019 at 8:01 PM <egranata@chromium.org> wrote:
>
> From: Enrico Granata <egranata@chromium.org>
>
> ACPI 5 added support for GpioInt resources as a way to provide
> information about interrupts mediated via a GPIO controller.
>
> Several device buses (e.g. SPI, I2C) have support for retrieving
> an IRQ specified via this type of resource, and providing it
> directly to the driver as an IRQ number.
>
> This is not currently done for the platform drivers, as platform_get_irq()
> does not try to parse GpioInt() resources. This requires drivers to
> either have to support only one possible IRQ resource, or to have code
> in place to try both as a failsafe.
>
> While there is a possibility of ambiguity for devices that exposes
> multiple IRQs, it is easy and feasible to support the common case
> of devices that only expose one IRQ which would be of either type
> depending on the underlying system's architecture.
>
> This commit adds support for parsing a GpioInt resource in order
> to fulfill a request for the index 0 IRQ for a platform device.
>
> Signed-off-by: Enrico Granata <egranata@chromium.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> ---
> Changes in v2:
> - only support IRQ index 0
>
> drivers/base/platform.c | 15 ++++++++++++++-
> 1 file changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/base/platform.c b/drivers/base/platform.c
> index 1c958eb33ef4d..0d3611cd1b3bc 100644
> --- a/drivers/base/platform.c
> +++ b/drivers/base/platform.c
> @@ -127,7 +127,20 @@ int platform_get_irq(struct platform_device *dev, unsigned int num)
> irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
> }
>
> - return r ? r->start : -ENXIO;
> + if (r)
> + return r->start;
> +
> + /*
> + * For the index 0 interrupt, allow falling back to GpioInt
> + * resources. While a device could have both Interrupt and GpioInt
> + * resources, making this fallback ambiguous, in many common cases
> + * the device will only expose one IRQ, and this fallback
> + * allows a common code path across either kind of resource.
> + */
> + if (num == 0 && has_acpi_companion(&dev->dev))
> + return acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num);
> +
> + return -ENXIO;
> #endif
> }
> EXPORT_SYMBOL_GPL(platform_get_irq);
> --
> 2.20.1.791.gb4d0f1c61a-goog
>
prev parent reply other threads:[~2019-02-24 19:35 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-07 18:59 [PATCH] driver: platform: Add support for GpioInt() ACPI to platform_get_irq() egranata
2019-02-07 19:02 ` Rafael J. Wysocki
2019-02-07 19:39 ` Andy Shevchenko
2019-02-07 19:45 ` Andy Shevchenko
2019-02-07 19:55 ` Enrico Granata
[not found] ` <CAPR809vnpuh8nOjU3QMCh6YJUKmtX92+bnHSUKGiAXAp6NwCHQ@mail.gmail.com>
2019-02-07 20:18 ` Andy Shevchenko
2019-02-07 20:29 ` Dmitry Torokhov
2019-02-11 10:30 ` Mika Westerberg
2019-02-11 15:42 ` Hans de Goede
2019-02-11 19:01 ` [PATCH v2] driver: platform: Support parsing GpioInt 0 in platform_get_irq() egranata
2019-02-11 19:25 ` Dmitry Torokhov
2019-02-12 7:29 ` Hans de Goede
2019-02-12 9:08 ` Mika Westerberg
2019-02-12 9:18 ` Rafael J. Wysocki
2019-02-12 12:46 ` Andy Shevchenko
2019-02-20 18:05 ` Brian Norris
2019-02-21 18:58 ` Enrico Granata
2019-02-21 19:34 ` [PATCH v3] " egranata
2019-02-22 9:03 ` Rafael J. Wysocki
2019-02-22 17:06 ` Brian Norris
2019-02-24 19:34 ` Rafael J. Wysocki [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=CAJZ5v0g-pWj9Fmg6W4+tt6QQCRssxcjVsHSDedO+ph3jsREhZw@mail.gmail.com \
--to=rafael@kernel.org \
--cc=andriy.shevchenko@linux.intel.com \
--cc=andy.shevchenko@gmail.com \
--cc=briannorris@chromium.org \
--cc=dtor@chromium.org \
--cc=egranata@chromium.org \
--cc=egranata@google.com \
--cc=enric.balletbo@collabora.com \
--cc=gregkh@linuxfoundation.org \
--cc=gwendal@chromium.org \
--cc=hdegoede@redhat.com \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mika.westerberg@linux.intel.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).