Re: [PATCH 14/14] arm/include/asm/io.h : added macros to read/write big/little endian register
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: 2011-08-31 07:35:07
* Pratyush Anand | 2011-08-30 17:28:01 [+0530]:
quoted hunk ↗ jump to hunk
diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h index 815efa2..32282b4 100644 --- a/arch/arm/include/asm/io.h +++ b/arch/arm/include/asm/io.h@@ -297,6 +297,14 @@ extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);extern int devmem_is_allowed(unsigned long pfn); #endif +/* Big Endian */ +#define out_be32(a, v) writel(__cpu_to_be32(v), a) +#define in_be32(a) __be32_to_cpu(readl(a)) + +/* Little endian */ +#define out_le32(a, v) writel(__cpu_to_le32(v), a) +#define in_le32(a) __le32_to_cpu(readl(a))
In LE-mode __le32_to_cpu() is NOP and you get a LE value. In BE-mode readl() will swap a and le32_to_cpu will swap a again. So you get a BE value. Is this what you want?
+
Please split this patch out and get it accepterd by ARM community. USB people won't merge this. Sebastian