[PATCH 02/19] device: Add a dev_request_mem_region function

[Jean-Christophe PLAGNIOL-VILLARD]

On 10:39 Tue 19 Jul     , Sascha Hauer wrote:
> We might want to add real resource tracking later. Also
> The first resource may not be a IORESOURCE_MEM at all.
> For these reasons introduce a wrapper function for
> driver so that they do not have to fiddle with resources
> directly.
> 
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> ---
>  include/driver.h |   14 ++++++++++++++
>  lib/driver.c     |   16 ++++++++++++++++
>  2 files changed, 30 insertions(+), 0 deletions(-)
> 
> diff --git a/include/driver.h b/include/driver.h
> index ed3df16..0fc254d 100644
> --- a/include/driver.h
> +++ b/include/driver.h
> @@ -188,6 +188,20 @@ static inline const char *dev_name(const struct device_d *dev)
>  	return dev_id(dev);
>  }
>  
> +/*
> + * get register base 'num' for a device
> + */
> +void __iomem *dev_get_mem_region(struct device_d *dev, int num);
> +
> +/*
> + * exlusively request register base 'num' for a device
> + */
> +static inline void __iomem *dev_request_mem_region(struct device_d *dev, int num)
> +{
> +	/* no resource tracking yet */
> +	return dev_get_mem_region(dev, num);
> +}
> +
>  /* linear list over all available devices
>   */
>  extern struct list_head device_list;
> diff --git a/lib/driver.c b/lib/driver.c
> index 95e42d5..50f065a 100644
> --- a/lib/driver.c
> +++ b/lib/driver.c
> @@ -233,6 +233,22 @@ int register_driver(struct driver_d *drv)
>  }
>  EXPORT_SYMBOL(register_driver);
>  
> +void __iomem *dev_get_mem_region(struct device_d *dev, int num)
> +{
> +	int i, n = 0;
> +
can we check num < dev->num_resources to
> +	for (i = 0; i < dev->num_resources; i++) {
> +		struct resource *res = &dev->resource[i];
> +		if ((res->flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM) {
resource_type here
> +			if (n == num)
> +				return (void __force __iomem *)res->start;
> +			n++;
> +		}
> +	}
> +
> +	return NULL;
> +}
EXPORT_SYMBOL too

Best Regards,
J.