On Fri, Feb 21, 2014 at 04:51:07PM +0100, Michal Simek wrote: > On 02/21/2014 04:42 PM, Felipe Balbi wrote: > > Hi, > > > > On Fri, Feb 21, 2014 at 02:41:03PM +0100, Michal Simek wrote: > >>>>> + /* Map the registers */ > >>>>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > >>>>> + udc->base_address = devm_ioremap_nocache(&pdev->dev, res->start, > >>>>> + resource_size(res)); > >>>> > >>>> use devm_ioremap_resource() instead. > >>> > >>> Also, res might be NULL. You should check that before dereferencing it. > >> > >> yes it is necessary for both cases with devm_ioremap_nocache > >> or with devm_ioremap_resource. > > > > read the source Luke: > > > > | void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res) > > | { > > | resource_size_t size; > > | const char *name; > > | void __iomem *dest_ptr; > > | > > | BUG_ON(!dev); > > | > > | if (!res || resource_type(res) != IORESOURCE_MEM) { > > ^^^^ > > already done for you > > > > | dev_err(dev, "invalid resource\n"); > > | return ERR_PTR(-EINVAL); > > | } > > | > > | size = resource_size(res); > > | name = res->name ?: dev_name(dev); > > | > > | if (!devm_request_mem_region(dev, res->start, size, name)) { > > | dev_err(dev, "can't request region for resource %pR\n", res); > > | return ERR_PTR(-EBUSY); > > | } > > | > > | if (res->flags & IORESOURCE_CACHEABLE) > > | dest_ptr = devm_ioremap(dev, res->start, size); > > | else > > | dest_ptr = devm_ioremap_nocache(dev, res->start, size); > > I have read it just not sure if IORESOURCE_CACHEABLE is setup by default > or not. > If yes, then you have to setup res->flags in your driver and have to > check it. you don't need IORESOURCe_CACHEABLE. It's fine the way it is, just use the helper function ;-). -- balbi
Attachment:
signature.asc
Description: Digital signature