[PATCH] devres: allow const resource arguments

[PATCH] devres: allow const resource arguments

[Arnd Bergmann]

devm_ioremap_resource() does not currently take 'const' arguments,
which results in a warning from the first driver trying to do it
anyway:

drivers/gpio/gpio-amd-fch.c: In function 'amd_fch_gpio_probe':
drivers/gpio/gpio-amd-fch.c:171:49: error: passing argument 2 of 'devm_ioremap_resource' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
  priv->base = devm_ioremap_resource(&pdev->dev, &amd_fch_gpio_iores);
                                                 ^~~~~~~~~~~~~~~~~~~

Change the prototype to allow it, as there is no real reason not to.

Fixes: 9bb2e0452508 ("gpio: amd: Make resource struct const")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
The warning is currently in Linus Walleij's gpio tree, so I would
suggest he can queue up this fix as well, if Greg (or whoever
feels responsible for devres) agrees.
---
 include/linux/device.h | 3 ++-
 lib/devres.c           | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/linux/device.h b/include/linux/device.h
index 4f65c424e5fd..f4ff92a6a56e 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -705,7 +705,8 @@ extern unsigned long devm_get_free_pages(struct device *dev,
 					 gfp_t gfp_mask, unsigned int order);
 extern void devm_free_pages(struct device *dev, unsigned long addr);
 
-void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
+void __iomem *devm_ioremap_resource(struct device *dev,
+				    const struct resource *res);
 
 void __iomem *devm_of_iomap(struct device *dev,
 			    struct device_node *node, int index,
diff --git a/lib/devres.c b/lib/devres.c
index 69bed2f38306..6a0e9bd6524a 100644
--- a/lib/devres.c
+++ b/lib/devres.c
@@ -131,7 +131,8 @@ EXPORT_SYMBOL(devm_iounmap);
  *	if (IS_ERR(base))
  *		return PTR_ERR(base);
  */
-void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res)
+void __iomem *devm_ioremap_resource(struct device *dev,
+				    const struct resource *res)
 {
 	resource_size_t size;
 	void __iomem *dest_ptr;
-- 
2.20.0

Re: [PATCH] devres: allow const resource arguments

[Greg Kroah-Hartman]

On Fri, Jun 28, 2019 at 04:59:45PM +0200, Arnd Bergmann wrote:
> devm_ioremap_resource() does not currently take 'const' arguments,
> which results in a warning from the first driver trying to do it
> anyway:
> 
> drivers/gpio/gpio-amd-fch.c: In function 'amd_fch_gpio_probe':
> drivers/gpio/gpio-amd-fch.c:171:49: error: passing argument 2 of 'devm_ioremap_resource' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
>   priv->base = devm_ioremap_resource(&pdev->dev, &amd_fch_gpio_iores);
>                                                  ^~~~~~~~~~~~~~~~~~~
> 
> Change the prototype to allow it, as there is no real reason not to.
> 
> Fixes: 9bb2e0452508 ("gpio: amd: Make resource struct const")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> The warning is currently in Linus Walleij's gpio tree, so I would
> suggest he can queue up this fix as well, if Greg (or whoever
> feels responsible for devres) agrees.

That's fine with me if Linus takes it:

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Re: [PATCH] devres: allow const resource arguments

[Enrico Weigelt, metux IT consult]

On 28.06.19 16:59, Arnd Bergmann wrote:
> devm_ioremap_resource() does not currently take 'const' arguments,
> which results in a warning from the first driver trying to do it
> anyway:
> 
> drivers/gpio/gpio-amd-fch.c: In function 'amd_fch_gpio_probe':
> drivers/gpio/gpio-amd-fch.c:171:49: error: passing argument 2 of 'devm_ioremap_resource' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
>   priv->base = devm_ioremap_resource(&pdev->dev, &amd_fch_gpio_iores);
>                                                  ^~~~~~~~~~~~~~~~~~~

<snip>

I've posted quite the same some time ago - no idea why it got no
response.


Reviwed-By: Enrico Weigelt <info@metux.net>


--mtx

-- 
Enrico Weigelt, metux IT consult
Free software and Linux embedded engineering
info@metux.net -- +49-151-27565287

Re: [PATCH] devres: allow const resource arguments

[Linus Walleij]

On Fri, Jun 28, 2019 at 5:00 PM Arnd Bergmann <arnd@arndb.de> wrote:

> devm_ioremap_resource() does not currently take 'const' arguments,
> which results in a warning from the first driver trying to do it
> anyway:
>
> drivers/gpio/gpio-amd-fch.c: In function 'amd_fch_gpio_probe':
> drivers/gpio/gpio-amd-fch.c:171:49: error: passing argument 2 of 'devm_ioremap_resource' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
>   priv->base = devm_ioremap_resource(&pdev->dev, &amd_fch_gpio_iores);
>                                                  ^~~~~~~~~~~~~~~~~~~
>
> Change the prototype to allow it, as there is no real reason not to.
>
> Fixes: 9bb2e0452508 ("gpio: amd: Make resource struct const")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Patch applied with Greg's and Enrico's ACKs.

Yours,
Linus Walleij