Re: [PATCH] Add cast to __iomem pointer in scsi drivers

From: Mark Lord
Date: Tue Feb 14 2006 - 15:44:24 EST


Takashi Iwai wrote:
At Tue, 14 Feb 2006 15:35:29 -0500,
linux-os (Dick Johnson) wrote:

On Tue, 14 Feb 2006, Takashi Iwai wrote:

Add the missing cast to __iomem pointer in some scsi drivers.
..
-#define WROUTDOOR(adapter,value) writel(value, (adapter)->base + 0x2C)
...
+#define WROUTDOOR(adapter,value) writel(value, (void __iomem *)((adapter)->base + 0x2C))
..
With all these casts, doesn't it point out that something is wrong
with writel(), writew(), readl(), and readw() ??? The cast's to
volatile types should be within the macros, not scattered
throughout everyone's driver code!

The patch is just for fixing compile warnings.

readl(), writel() and co are inline functions, and they should be cast
explicitly on the caller side.

I think Linus's intent when he added the __iomem "feature", was that code
should change the underlying data declarations to match. So rather than
casting things left and right, and defeating compiler diagnostics by doing so,
perhaps the actual data type for "base" et al. should get changed to match.

Cheers
-
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