>> -----Original Message-----
>> From: Rob Herring [mailto:robherring2 at gmail.com]
>> Sent: Thursday, August 30, 2012 2:27 PM
>> To: Karicheri, Muralidharan
>> Cc: grant.likely at secretlab.ca; devicetree-discuss at lists.ozlabs.org; linux-
>> kernel at vger.kernel.org
>> Subject: Re: [PATCH] of: add devres version of of_iomap
>>
>> On 08/30/2012 10:32 AM, Murali Karicheri wrote:
>> > This adds devres version of the of_iomap() to allow resource to be cleaned
>> > through devres.
>>
>> If you have a struct device, then don't you already have a resource and
>> can just use devm_ioremap in a driver? New drivers should not be using
>> of_iomap.
>>
That is the point. If you do a grep under driver, there are many drivers using the pattern
like this. This helper function is mean to replace this code.
>From dma/sirf-dma.c
ret = of_address_to_resource(dn, 0, &res);
if (ret) {
dev_err(dev, "Error parsing memory region!\n");
goto error;
}
regs_start = res.start;
regs_size = resource_size(&res);
base = devm_ioremap(dev, regs_start, regs_size);
if (!base) {
dev_err(dev, "Error mapping memory region!\n");
goto error;
}
Other instances.
edac/mpc85xx_edac.c
media/video/fsl-viu.c
mtd/nand/mpc5121_nfc.c
Some of these code uses devm_request_mem_region() as well. Isn't a good idea to add this helper
that can be called by new drivers to replace this sequence? I could update the patch to do this call
as well?
>> Rob
>>
>> >
>> > Signed-off-by: Murali Karicheri <m-karicheri2 at ti.com>
>> > ---
>> > drivers/of/address.c | 26 ++++++++++++++++++++++++--
>> > include/linux/of_address.h | 2 ++
>> > 2 files changed, 26 insertions(+), 2 deletions(-)
>> >
>> > diff --git a/drivers/of/address.c b/drivers/of/address.c
>> > index 7e262a6..d3da426 100644
>> > --- a/drivers/of/address.c
>> > +++ b/drivers/of/address.c
>> > @@ -602,10 +602,9 @@ struct device_node
>> *of_find_matching_node_by_address(struct device_node *from,
>> > return NULL;
>> > }
>> >
>> > -
>> > /**
>> > * of_iomap - Maps the memory mapped IO for a given device_node
>> > - * @device: the device whose io range will be mapped
>> > + * @device_node: Ptr to the device node that has the reg property
>> > * @index: index of the io range
>> > *
>> > * Returns a pointer to the mapped memory
>> > @@ -620,3 +619,26 @@ void __iomem *of_iomap(struct device_node *np, int index)
>> > return ioremap(res.start, resource_size(&res));
>> > }
>> > EXPORT_SYMBOL(of_iomap);
>> > +
>> > +/**
>> > + * of_devm_iomap - devres version of of_iomap
>> > + * @device: the device whose io range will be mapped
>> > + * @index: index of the io range
>> > + *
>> > + * Returns a pointer to the mapped memory
>> > + */
>> > +void __iomem *of_devm_iomap(struct device *dev, int index)
>> > +{
>> > + struct device_node *np;
>> > + struct resource res;
>> > +
>> > + if (!dev)
>> > + return NULL;
>> > +
>> > + np = dev->of_node;
>> > + if (of_address_to_resource(np, index, &res))
>> > + return NULL;
>> > +
>> > + return devm_ioremap(dev, res.start, resource_size(&res));
>> > +}
>> > +EXPORT_SYMBOL(of_devm_iomap);
>> > diff --git a/include/linux/of_address.h b/include/linux/of_address.h
>> > index 01b925a..67efa5f 100644
>> > --- a/include/linux/of_address.h
>> > +++ b/include/linux/of_address.h
>> > @@ -3,6 +3,7 @@
>> > #include <linux/ioport.h>
>> > #include <linux/errno.h>
>> > #include <linux/of.h>
>> > +#include <linux/device.h>
>> >
>> > #ifdef CONFIG_OF_ADDRESS
>> > extern u64 of_translate_address(struct device_node *np, const __be32 *addr);
>> > @@ -13,6 +14,7 @@ extern struct device_node *of_find_matching_node_by_address(
>> > const struct of_device_id *matches,
>> > u64 base_address);
>> > extern void __iomem *of_iomap(struct device_node *device, int index);
>> > +extern void __iomem *of_devm_iomap(struct device *dev, int index);
>> >
>> > /* Extract an address from a device, returns the region size and
>> > * the address space flags too. The PCI version uses a BAR number
>> >