[alsa-devel] [PATCH 1/2] lib: devres: add a helper function for ioremap_wc

Abhilash Kesavan kesavan.abhilash at gmail.com
Sat Jan 10 04:30:54 CET 2015


Hi Greg,

On Thu, Dec 11, 2014 at 8:28 AM, Abhilash Kesavan <a.kesavan at samsung.com> wrote:
> Implement a resource managed writecombine ioremap function.
>
> Signed-off-by: Abhilash Kesavan <a.kesavan at samsung.com>
> ---
>  Documentation/driver-model/devres.txt |    1 +
>  include/linux/io.h                    |    2 ++
>  lib/devres.c                          |   28 ++++++++++++++++++++++++++++
>  3 files changed, 31 insertions(+)
>
> diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
> index b5ab416..0f80cee 100644
> --- a/Documentation/driver-model/devres.txt
> +++ b/Documentation/driver-model/devres.txt
> @@ -274,6 +274,7 @@ IOMAP
>    devm_ioport_unmap()
>    devm_ioremap()
>    devm_ioremap_nocache()
> +  devm_ioremap_wc()
>    devm_ioremap_resource() : checks resource, requests memory region, ioremaps
>    devm_iounmap()
>    pcim_iomap()
> diff --git a/include/linux/io.h b/include/linux/io.h
> index fa02e55..42b33f0 100644
> --- a/include/linux/io.h
> +++ b/include/linux/io.h
> @@ -64,6 +64,8 @@ void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
>                            resource_size_t size);
>  void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
>                                    resource_size_t size);
> +void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
> +                                  resource_size_t size);
>  void devm_iounmap(struct device *dev, void __iomem *addr);
>  int check_signature(const volatile void __iomem *io_addr,
>                         const unsigned char *signature, int length);
> diff --git a/lib/devres.c b/lib/devres.c
> index 0f1dd2e..e8e1738 100644
> --- a/lib/devres.c
> +++ b/lib/devres.c
> @@ -72,6 +72,34 @@ void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
>  EXPORT_SYMBOL(devm_ioremap_nocache);
>
>  /**
> + * devm_ioremap_wc - Managed ioremap_wc()
> + * @dev: Generic device to remap IO address for
> + * @offset: BUS offset to map
> + * @size: Size of map
> + *
> + * Managed ioremap_wc().  Map is automatically unmapped on driver detach.
> + */
> +void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
> +                          resource_size_t size)
> +{
> +       void __iomem **ptr, *addr;
> +
> +       ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
> +       if (!ptr)
> +               return NULL;
> +
> +       addr = ioremap_wc(offset, size);

These two patches were applied yesterday to the char-misc tree, but
have broken build on m32r and maybe other platforms too which do not
have ioremap_wc defined. Unfortunately I missed catching this as I
built the patches only for arm64 and arm32, sorry for the trouble.
There was a patch posted a while back which added ioremap_wc for m32r
(https://lkml.org/lkml/2013/6/26/795). I would have to do something
similar for all the other archs which do not have it or is there some
other solution ?

Please drop these patches in the interim so that the build is fixed.

Regards,
Abhilash
> +       if (addr) {
> +               *ptr = addr;
> +               devres_add(dev, ptr);
> +       } else
> +               devres_free(ptr);
> +
> +       return addr;
> +}
> +EXPORT_SYMBOL(devm_ioremap_wc);
> +
> +/**
>   * devm_iounmap - Managed iounmap()
>   * @dev: Generic device to unmap for
>   * @addr: Address to unmap
> --
> 1.7.9.5
>


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