hwrng: timeriomem - Use phys address rather than virt

There is no ioremap'ing or anything in timeriomem-rng.c as I foolishly
used already remapped virtual addresses instead of passing the physical
address to be polled.

This patch fixes this flaw and lets developers do the Right Thing(tm).

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

1 files changed, 35 insertions, 4 deletions

diff --git a/drivers/char/hw_random/timeriomem-rng.c b/drivers/char/hw_random/timeriomem-rng.c
index 10ad41be5897..dcd352ad0e7f 100644
--- a/drivers/char/hw_random/timeriomem-rng.c
+++ b/drivers/char/hw_random/timeriomem-rng.c
@@ -90,10 +90,30 @@ static struct hwrng timeriomem_rng_ops = {
 
 static int __init timeriomem_rng_probe(struct platform_device *pdev)
 {
+        struct resource *res, *mem;
         int ret;
 
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+        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->period != 0
                 && usecs_to_jiffies(timeriomem_rng_data->period) > 0) {
                 timeriomem_rng_timer.expires = jiffies;
@@ -104,23 +124,34 @@ static int __init timeriomem_rng_probe(struct platform_device *pdev)
         timeriomem_rng_data->present = 1;
 
         ret = hwrng_register(&timeriomem_rng_ops);
-        if (ret) {
-                dev_err(&pdev->dev, "problem registering\n");
-                return ret;
-        }
+        if (ret)
+                goto err_register;
 
         dev_info(&pdev->dev, "32bits from 0x%p @ %dus\n",
                         timeriomem_rng_data->address,
                         timeriomem_rng_data->period);
 
         return 0;
+
+err_register:
+        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;
 }