ARM: mvebu: improve PMSU driver to request its resource

Until now, the PMSU driver was using of_iomap() to map its registers,
but of_iomap() doesn't call request_mem_region(). This commit fixes
the memory mapping code of the PMSU to do so, which will also be
useful for a later commit since we will need to adjust the resource
base address and size for Device Tree backward compatibility.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483433-25836-4-git-send-email-thomas.petazzoni@free-electrons.com
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

1 files changed, 31 insertions, 5 deletions

diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c
index 1807639173b1..b337fe56bae5 100644
--- a/arch/arm/mach-mvebu/pmsu.c
+++ b/arch/arm/mach-mvebu/pmsu.c
@@ -16,6 +16,8 @@
  * other SOC units
  */
 
+#define pr_fmt(fmt) "mvebu-pmsu: " fmt
+
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/of_address.h>
@@ -63,15 +65,39 @@ int armada_xp_boot_cpu(unsigned int cpu_id, void *boot_addr)
 static int __init armada_370_xp_pmsu_init(void)
 {
         struct device_node *np;
+        struct resource res;
+        int ret = 0;
 
         np = of_find_matching_node(NULL, of_pmsu_table);
-        if (np) {
-                pr_info("Initializing Power Management Service Unit\n");
-                pmsu_mp_base = of_iomap(np, 0);
-                of_node_put(np);
+        if (!np)
+                return 0;
+
+        pr_info("Initializing Power Management Service Unit\n");
+
+        if (of_address_to_resource(np, 0, &res)) {
+                pr_err("unable to get resource\n");
+                ret = -ENOENT;
+                goto out;
         }
 
-        return 0;
+        if (!request_mem_region(res.start, resource_size(&res),
+                                np->full_name)) {
+                pr_err("unable to request region\n");
+                ret = -EBUSY;
+                goto out;
+        }
+
+        pmsu_mp_base = ioremap(res.start, resource_size(&res));
+        if (!pmsu_mp_base) {
+                pr_err("unable to map registers\n");
+                release_mem_region(res.start, resource_size(&res));
+                ret = -ENOMEM;
+                goto out;
+        }
+
+ out:
+        of_node_put(np);
+        return ret;
 }
 
 early_initcall(armada_370_xp_pmsu_init);