Re: [PATCH v2 1/3] driver core: platform: Add the helper function devm_platform_get_and_ioremap_resource_byname()
From: Greg KH
Date: Thu Sep 02 2021 - 02:52:56 EST
On Thu, Sep 02, 2021 at 02:37:00PM +0800, Cai Huoqing wrote:
> Since provide the helper function devm_platform_ioremap_resource_byname()
> which is wrap platform_get_resource_byname() and devm_ioremap_resource().
> But sometimes, many drivers still need to use the resource variables
> obtained by platform_get_resource(). In these cases, provide this helper
> function devm_platform_get_and_ioremap_resource_byname().
> Signed-off-by: Cai Huoqing <caihuoqing@xxxxxxxxx>
> v1->v2: Resend this patch as part of a patch series that uses
> the new function.
> drivers/base/platform.c | 30 ++++++++++++++++++++++++++----
> include/linux/platform_device.h | 3 +++
> 2 files changed, 29 insertions(+), 4 deletions(-)
> diff --git a/drivers/base/platform.c b/drivers/base/platform.c
> index 652531f67135..34bb581338d9 100644
> --- a/drivers/base/platform.c
> +++ b/drivers/base/platform.c
> @@ -124,6 +124,31 @@ void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
> + * devm_platform_get_and_ioremap_resource_byname - call devm_ioremap_resource() for a
> + * platform device and get resource
> + *
> + * @pdev: platform device to use both for memory resource lookup as well as
> + * resource management
> + * @name: name of the resource
> + * @res: optional output parameter to store a pointer to the obtained resource.
> + *
> + * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
> + * on failure.
> + */
> +void __iomem *
> +devm_platform_get_and_ioremap_resource_byname(struct platform_device *pdev,
> + const char *name, struct resource **res)
> + struct resource *r;
> + r = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
> + if (res)
> + *res = r;
You forgot to check the return value of this call :(
Which means you did not test this? Why not?
But step back, _WHY_ is this needed at all? How deep are we going to
get with the "devm_platform_get_and_do_this_and_that_and_that" type
You show 2 users of this call, and they save what, 1-2 lines of code
What is the real need for this?