• Cyril Bur's avatar
    drivers/misc: Aspeed LPC control fix compile error and warning · 132c93d4
    Cyril Bur authored
    pgprot_dmachoerent() is not defined on every architecture. Having
    COMPILE_TEST set for the driver causes it to be compiled on
    architectures which do not have pgprot_dmachoerent():
        drivers/misc/aspeed-lpc-ctrl.c: In function 'aspeed_lpc_ctrl_mmap':
        drivers/misc/aspeed-lpc-ctrl.c:51:9: error: implicit declaration of
            function 'pgprot_dmacoherent' [-Werror=implicit-function-declaration]
            prot = pgprot_dmacoherent(prot);
    
    There are two possible solutions:
        1. Remove COMPILE_TEST to ensure the driver is only compiled on ARM
        2. Use pgprot_noncached() instead of pgprot_dmachoerent()
    
    The first option results in less compile testing of the LPC control
    driver which is undesirable.
    The second option uses a function that is declared on all architectures
    and therefore should always build. Currently there is no practical
    difference between pgprot_noncached() and pgprot_dmachoerent() for the
    aspeed chips that this driver is compatible with. The reason for
    pgprot_dmachoerent() was that there may be chips made at some point in
    the future that could include hardware that pgprot_dmachoerent() could
    optimise for. As none of this hardware has even been announced there
    isn't really a need for pgprot_dmachoerent().
    
    Using pgprot_noncached() is completely correct and optimal for all
    existing hardware on which the LPC control driver will run.
    
    This commit also addresses that phys_addr_t should be printed using %pap
    rather than %x:
        In file included from include/linux/miscdevice.h:6:0,
                         from drivers/misc/aspeed-lpc-ctrl.c:11:
        drivers/misc/aspeed-lpc-ctrl.c: In function 'aspeed_lpc_ctrl_probe':
        drivers/misc/aspeed-lpc-ctrl.c:232:17: warning: format '%x' expects
            argument of type 'unsigned int', but argument 3 has type 'phys_addr_t
            {aka long long unsigned int}' [-Wformat=]
            dev_info(dev, "Loaded at 0x%08x (0x%08x)\n",
    Signed-off-by: default avatarCyril Bur <cyrilbur@gmail.com>
    Reported-by: default avatarkbuild test robot <fengguang.wu@intel.com>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    132c93d4
aspeed-lpc-ctrl.c 6.78 KB