lkml.org 
[lkml]   [2019]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] devres: always use dev_name() in devm_ioremap_resource()
Date
devm_ioremap_resource() prefers calling devm_request_mem_region() with a
resource name instead of a device name -- this looks pretty iff a resource
name isn't specified via a device tree with a "reg-names" property (in this
case, a resource name is set to a device node's full name), but if it is,
it doesn't really scale since these names are only unique to a given device
node, not globally; so, looking at the output of 'cat /proc/iomem', you do
not have an idea which memory region belongs to which device (see "dirmap",
"regs", and "wbuf" lines below):

08000000-0bffffff : dirmap
48000000-bfffffff : System RAM
48000000-48007fff : reserved
48080000-48b0ffff : Kernel code
48b10000-48b8ffff : reserved
48b90000-48c7afff : Kernel data
bc6a4000-bcbfffff : reserved
bcc0f000-bebfffff : reserved
bec0e000-bec0efff : reserved
bec11000-bec11fff : reserved
bec12000-bec14fff : reserved
bec15000-bfffffff : reserved
e6050000-e605004f : gpio@e6050000
e6051000-e605104f : gpio@e6051000
e6052000-e605204f : gpio@e6052000
e6053000-e605304f : gpio@e6053000
e6054000-e605404f : gpio@e6054000
e6055000-e605504f : gpio@e6055000
e6060000-e606050b : pin-controller@e6060000
e6e60000-e6e6003f : e6e60000.serial
e7400000-e7400fff : ethernet@e7400000
ee200000-ee2001ff : regs
ee208000-ee2080ff : wbuf

I think that devm_request_mem_region() should be called with dev_name()
despite the region names won't look as pretty as before (however, we gain
more consistency with e.g. the serial driver:

08000000-0bffffff : ee200000.rpc
48000000-bfffffff : System RAM
48000000-48007fff : reserved
48080000-48b0ffff : Kernel code
48b10000-48b8ffff : reserved
48b90000-48c7afff : Kernel data
bc6a4000-bcbfffff : reserved
bcc0f000-bebfffff : reserved
bec0e000-bec0efff : reserved
bec11000-bec11fff : reserved
bec12000-bec14fff : reserved
bec15000-bfffffff : reserved
e6050000-e605004f : e6050000.gpio
e6051000-e605104f : e6051000.gpio
e6052000-e605204f : e6052000.gpio
e6053000-e605304f : e6053000.gpio
e6054000-e605404f : e6054000.gpio
e6055000-e605504f : e6055000.gpio
e6060000-e606050b : e6060000.pin-controller
e6e60000-e6e6003f : e6e60000.serial
e7400000-e7400fff : e7400000.ethernet
ee200000-ee2001ff : ee200000.rpc
ee208000-ee2080ff : ee200000.rpc

Fixes: 72f8c0bfa0de ("lib: devres: add convenience function to remap a resource")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

---
The patch is against the 'driver-core-linus' branch of Greg KH's 'driver-core'
repo (for the lack of a better base).

lib/devres.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

Index: driver-core/lib/devres.c
===================================================================
--- driver-core.orig/lib/devres.c
+++ driver-core/lib/devres.c
@@ -134,7 +134,6 @@ EXPORT_SYMBOL(devm_iounmap);
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);
@@ -145,9 +144,8 @@ void __iomem *devm_ioremap_resource(stru
}

size = resource_size(res);
- name = res->name ?: dev_name(dev);

- if (!devm_request_mem_region(dev, res->start, size, name)) {
+ if (!devm_request_mem_region(dev, res->start, size, dev_name(dev))) {
dev_err(dev, "can't request region for resource %pR\n", res);
return IOMEM_ERR_PTR(-EBUSY);
}
\
 
 \ /
  Last update: 2019-01-29 11:57    [W:0.055 / U:50.436 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site