[PATCH 05/25] OMAP4: Use WARN_ON() instead of BUG_ON() with graceful exit

On Mon, Sep 05, 2011 at 04:12:02PM +0530, Santosh wrote:

On Monday 05 September 2011 03:41 PM, Sergei Shtylyov wrote:

quoted

Hello.

On 04-09-2011 17:54, Santosh Shilimkar wrote:

quoted

OMAP4 L2X0 initialisation code uses BUG_ON() for the ioremap()
failure scenarios.

quoted

Use WARN_ON() instead and allow graceful function exits.

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This was suggsted by Kevin Hilman[off-list ref] during
OMAP4 PM code review.

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Signed-off-by: Santosh Shilimkar<redacted>
Cc: Kevin Hilman<redacted>
---
arch/arm/mach-omap2/omap4-common.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

quoted

diff --git a/arch/arm/mach-omap2/omap4-common.c

b/arch/arm/mach-omap2/omap4-common.c
index 4791370..4904025 100644

--- a/arch/arm/mach-omap2/omap4-common.c
+++ b/arch/arm/mach-omap2/omap4-common.c

@@ -121,7 +121,8 @@ static int __init omap_l2_cache_init(void)

/* Static mapping, never released */
l2cache_base = ioremap(OMAP44XX_L2CACHE_BASE, SZ_4K);
- BUG_ON(!l2cache_base);
+ if (WARN_ON(!l2cache_base))
+ return -ENODEV;

Rather ENOMEM...

Nope. Even though it's related to memory, it's
a memory controller so DEV is right.

No it's not.  The most likely reason ioremap() fails is because:

1. it's run out of memory for the metadata or page tables.
2. you passed it an invalid memory type (unlikely, you're using ioremap
   which uses a fixed known good type).
3. the address was >4GB but was not section aligned (also unlikely).

Therefore, the error code should be "out of memory" not "no such device".