Re: [PATCH 1/2] driver core: platform: Introduce platform_get_irq_optional() - Greg Kroah-Hartman

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Thierry Reding <thierry.reding@gmail.com>
Cc: "Rafael J . Wysocki" <rafael@kernel.org>,
	Kamil Debski <kamil@wypas.org>,
	Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
	Jean Delvare <jdelvare@suse.com>,
	Guenter Roeck <linux@roeck-us.net>,
	Stephen Boyd <swboyd@chromium.org>,
	linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] driver core: platform: Introduce platform_get_irq_optional()
Date: Thu, 29 Aug 2019 12:10:28 +0200	[thread overview]
Message-ID: <20190829101028.GA20197@kroah.com> (raw)
In-Reply-To: <20190829074408.GA17754@ulmo>

On Thu, Aug 29, 2019 at 09:44:08AM +0200, Thierry Reding wrote:
> On Wed, Aug 28, 2019 at 10:34:10AM +0200, Thierry Reding wrote:
> > From: Thierry Reding <treding@nvidia.com>
> > 
> > In some cases the interrupt line of a device is optional. Introduce a
> > new platform_get_irq_optional() that works much like platform_get_irq()
> > but does not output an error on failure to find the interrupt.
> > 
> > Signed-off-by: Thierry Reding <treding@nvidia.com>
> > ---
> >  drivers/base/platform.c         | 22 ++++++++++++++++++++++
> >  include/linux/platform_device.h |  1 +
> >  2 files changed, 23 insertions(+)
> > 
> > diff --git a/drivers/base/platform.c b/drivers/base/platform.c
> > index 8ad701068c11..0dda6ade50fd 100644
> > --- a/drivers/base/platform.c
> > +++ b/drivers/base/platform.c
> > @@ -192,6 +192,28 @@ int platform_get_irq(struct platform_device *dev, unsigned int num)
> >  }
> >  EXPORT_SYMBOL_GPL(platform_get_irq);
> >  
> > +/**
> > + * platform_get_irq_optional - get an optional IRQ for a device
> > + * @dev: platform device
> > + * @num: IRQ number index
> > + *
> > + * Gets an IRQ for a platform device. Device drivers should check the return
> > + * value for errors so as to not pass a negative integer value to the
> > + * request_irq() APIs. This is the same as platform_get_irq(), except that it
> > + * does not print an error message if an IRQ can not be obtained.
> > + *
> > + * Example:
> > + *		int irq = platform_get_irq_optional(pdev, 0);
> > + *		if (irq < 0)
> > + *			return irq;
> > + *
> > + * Return: IRQ number on success, negative error number on failure.
> > + */
> > +int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
> > +{
> > +	return __platform_get_irq(dev, num);
> > +}
> 
> Oh my... this is embarrassing, but the kbuild test robot reported that
> the second patch here fails to build because I forgot to export this
> symbol. I've attached a patch that fixes it.
> 
> Thierry
> 
> > +
> >  /**
> >   * platform_irq_count - Count the number of IRQs a platform device uses
> >   * @dev: platform device
> > diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
> > index 37e15a935a42..35bc4355a9df 100644
> > --- a/include/linux/platform_device.h
> > +++ b/include/linux/platform_device.h
> > @@ -58,6 +58,7 @@ extern void __iomem *
> >  devm_platform_ioremap_resource(struct platform_device *pdev,
> >  			       unsigned int index);
> >  extern int platform_get_irq(struct platform_device *, unsigned int);
> > +extern int platform_get_irq_optional(struct platform_device *, unsigned int);
> >  extern int platform_irq_count(struct platform_device *);
> >  extern struct resource *platform_get_resource_byname(struct platform_device *,
> >  						     unsigned int,
> > -- 
> > 2.22.0
> > 

> From 0f7695c4d3f30b2946c97160b717de03c3deb73f Mon Sep 17 00:00:00 2001
> From: Thierry Reding <treding@nvidia.com>
> Date: Thu, 29 Aug 2019 09:29:32 +0200
> Subject: [PATCH] driver core: platform: Export platform_get_irq_optional()
> 
> This function can be used by modules, so it needs to be exported.
> 
> Reported-by: kbuild test robot <lkp@intel.com>
> Signed-off-by: Thierry Reding <treding@nvidia.com>
> ---
>  drivers/base/platform.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/base/platform.c b/drivers/base/platform.c
> index 014dc07b0056..b6c6c7d97d5b 100644
> --- a/drivers/base/platform.c
> +++ b/drivers/base/platform.c
> @@ -194,6 +194,7 @@ int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
>  {
>  	return __platform_get_irq(dev, num);
>  }
> +EXPORT_SYMBOL_GPL(platform_get_irq_optional);
>  
>  /**
>   * platform_irq_count - Count the number of IRQs a platform device uses
> -- 
> 2.22.0
> 

Now merged, thanks.

greg k-h