hwrng: timeriomem - Fix potential oops (request_mem_region/__devinit)

Fixed oops when calling device_unregister followed by device_register
(changing __init to __devinit) and removed request_mem_region() as
platform_device_register already does this which can result in EBUSY

Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 6 insertions, 20 deletions

diff --git a/drivers/char/hw_random/timeriomem-rng.c b/drivers/char/hw_random/timeriomem-rng.c
index dcd352ad0e7f..a94e930575f2 100644
--- a/drivers/char/hw_random/timeriomem-rng.c
+++ b/drivers/char/hw_random/timeriomem-rng.c
@@ -88,9 +88,9 @@ static struct hwrng timeriomem_rng_ops = {
         .priv           = 0,
 };
 
-static int __init timeriomem_rng_probe(struct platform_device *pdev)
+static int __devinit timeriomem_rng_probe(struct platform_device *pdev)
 {
-        struct resource *res, *mem;
+        struct resource *res;
         int ret;
 
         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -98,21 +98,12 @@ static int __init timeriomem_rng_probe(struct platform_device *pdev)
         if (!res)
                 return -ENOENT;
 
-        mem = request_mem_region(res->start, res->end - res->start + 1,
-                                 pdev->name);
-        if (mem == NULL)
-                return -EBUSY;
-
-        dev_set_drvdata(&pdev->dev, mem);
-
         timeriomem_rng_data = pdev->dev.platform_data;
 
         timeriomem_rng_data->address = ioremap(res->start,
                                                 res->end - res->start + 1);
-        if (!timeriomem_rng_data->address) {
-                ret = -ENOMEM;
-                goto err_ioremap;
-        }
+        if (!timeriomem_rng_data->address)
+                return -EIO;
 
         if (timeriomem_rng_data->period != 0
                 && usecs_to_jiffies(timeriomem_rng_data->period) > 0) {
@@ -125,7 +116,7 @@ static int __init timeriomem_rng_probe(struct platform_device *pdev)
 
         ret = hwrng_register(&timeriomem_rng_ops);
         if (ret)
-                goto err_register;
+                goto failed;
 
         dev_info(&pdev->dev, "32bits from 0x%p @ %dus\n",
                         timeriomem_rng_data->address,
@@ -133,24 +124,19 @@ static int __init timeriomem_rng_probe(struct platform_device *pdev)
 
         return 0;
 
-err_register:
+failed:
         dev_err(&pdev->dev, "problem registering\n");
         iounmap(timeriomem_rng_data->address);
-err_ioremap:
-        release_resource(mem);
 
         return ret;
 }
 
 static int __devexit timeriomem_rng_remove(struct platform_device *pdev)
 {
-        struct resource *mem = dev_get_drvdata(&pdev->dev);
-
         del_timer_sync(&timeriomem_rng_timer);
         hwrng_unregister(&timeriomem_rng_ops);
 
         iounmap(timeriomem_rng_data->address);
-        release_resource(mem);
 
         return 0;
 }