Messages in this thread | | | Date | Fri, 9 Sep 2016 14:56:53 -0700 | From | Guenter Roeck <> | Subject | Re: [PATCH v2] hwmon: xgene: access mailbox as RAM |
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On Fri, Sep 09, 2016 at 10:10:45PM +0200, Arnd Bergmann wrote: > The newly added hwmon driver fails to build in an allmodconfig > kernel: > > ERROR: "memblock_is_memory" [drivers/hwmon/xgene-hwmon.ko] undefined! > > According to comments in the code, the mailbox is a shared memory region, > not a set of MMIO registers, so we should use memremap() for mapping it > instead of ioremap or acpi_os_ioremap, and pointer dereferences instead > of readl/writel. > > The driver already uses plain kernel pointers, so it's a bit unusual > to work with functions that operate on __iomem pointers, and this > fixes that part too. > > I'm using READ_ONCE/WRITE_ONCE here to keep the existing behavior > regarding the ordering of the accesses from the CPU, but note that > there are no barriers (also unchanged from before). > > I'm also keeping the endianess behavior, though I'm unsure whether > the message data was supposed to be in LE32 format in the first > place, it's possible this was meant to be interpreted as a byte > stream instead. > > Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Applied after 's/endianess/endianness/' to make checkpatch happy.
Thanks, Guenter
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