hpet: Support 32-bit userspace
hpet_compat_ioctl and read file operations failed to handle parameters from 32-bit userspace and thus samples/timers/hpet_example.c fails as below. root@intel-x86-64:~# ./hpet_example-32.out poll /dev/hpet 1 2 -hpet: executing poll hpet_poll: HPET_IRQFREQ failed This patch fixes cmd and arg handling in hpet_compat_ioctl and adds compat handling for 32-bit userspace in hpet_read. hpet_example now shows that it works for both 64-bit and 32-bit. root@intel-x86-64:~# ./hpet_example-32.out poll /dev/hpet 1 2 -hpet: executing poll hpet_poll: info.hi_flags 0x0 hpet_poll: expired time = 0xf4298 hpet_poll: revents = 0x1 hpet_poll: data 0x1 hpet_poll: expired time = 0xf4235 hpet_poll: revents = 0x1 hpet_poll: data 0x1 root@intel-x86-64:~# ./hpet_example-64.out poll /dev/hpet 1 2 -hpet: executing poll hpet_poll: info.hi_flags 0x0 hpet_poll: expired time = 0xf42a1 hpet_poll: revents = 0x1 hpet_poll: data 0x1 hpet_poll: expired time = 0xf4232 hpet_poll: revents = 0x1 hpet_poll: data 0x1 Cc: stable@vger.kernel.org Signed-off-by:He Zhe <zhe.he@windriver.com> Fixes: 54066a57 ("hpet: kill BKL, add compat_ioctl") Reviewed-by: