On Fri, Dec 17, 2021 at 02:44:43AM +0000, Tony Huang 黃懷厚 wrote: > Dear Arnd: > > On Thu, Dec 16, 2021 at 2:38 AM Tony Huang <tonyhuang.sunplus@xxxxxxxxx<mailto:tonyhuang.sunplus@xxxxxxxxx>> wrote: > >> > >> IOP (IO Processor) embedded inside SP7021 which is used as > >> Processor for I/O control, RTC wake-up and cooperation with > >> CPU & PMC in power management purpose. > >> The IOP core is DQ8051, so also named IOP8051, > >> it supports dedicated JTAG debug pins which share with SP7021. > >> In standby mode operation, the power spec reach 400uA. > >> > >> Signed-off-by: Tony Huang <tonyhuang.sunplus@xxxxxxxxx<mailto:tonyhuang.sunplus@xxxxxxxxx>> > >> --- > >> Changes in v4: > >> - Addressed comments from Arnd Bergmann. > > >I don't think you did: I asked you specifically to add code to interact with > >the existing in-kernel interfaces to use the functionality provided by the > >device. Pick any (at least two) subsystems and add support, but leave > >out any custom user space interfaces (miscdevice, debugfs, sysfs, ...) > >for the moment. > > 1. IOP can run sp_iop_platform_driver_shudown() through the poweroff command and the kernel. Perform system power-off actions. > 2. Wake up the system by relying on the 8051 internal RTC wake-up mechanism and external GPIO input signals to wake up. > 3.So you ask me to control IOP(8051) through file_operations, not through DEVICE_ATTR Your DEVICE_ATTR() calls did not do anything normal, they did not print out or accept data through sysfs at all. That is not ok. thanks, greg k-h
