• Arnd Bergmann's avatar
    dmaengine: dw-edma: fix endianess confusion · 6f4722b1
    Arnd Bergmann authored
    When building with 'make C=1', sparse reports an endianess bug:
    
    drivers/dma/dw-edma/dw-edma-v0-debugfs.c:60:30: warning: cast removes address space of expression
    drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: warning: incorrect type in argument 1 (different address spaces)
    drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24:    expected void const volatile [noderef] <asn:2>*addr
    drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24:    got void *[assigned] ptr
    drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: warning: incorrect type in argument 1 (different address spaces)
    drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24:    expected void const volatile [noderef] <asn:2>*addr
    drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24:    got void *[assigned] ptr
    drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: warning: incorrect type in argument 1 (different address spaces)
    drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24:    expected void const volatile [noderef] <asn:2>*addr
    drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24:    got void *[assigned] ptr
    
    The current code is clearly wrong, as it passes an endian-swapped word
    into a register function where it gets swapped again. Just pass the variables
    directly into lower_32_bits()/upper_32_bits().
    
    Fixes: 7e4b8a4f ("dmaengine: Add Synopsys eDMA IP version 0 support")
    Link: https://lore.kernel.org/lkml/20190617131820.2470686-1-arnd@arndb.de/Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
    Acked-by: default avatarGustavo Pimentel <gustavo.pimentel@synopsys.com>
    Link: https://lore.kernel.org/r/20190722124457.1093886-3-arnd@arndb.deSigned-off-by: default avatarVinod Koul <vkoul@kernel.org>
    6f4722b1
dw-edma-v0-core.c 8.36 KB