On Monday 08 April 2013, Tomasz Figa wrote: > On Saturday 06 of April 2013 00:24:18 Tomasz Figa wrote: > > On Friday 05 of April 2013 21:54:21 Arnd Bergmann wrote: > > > On Friday 05 April 2013, Tomasz Figa wrote: > > > > I'm not sure what you mean by a register-level interface. Something like > > samsung_pwm_update_reg(reg, mask, val), which modifies bitfields > > according to the mask and value with appropriate synchronization? If > > yes, this solves only the problem of access to shared registers. > > > > The other problems that remain: > > > > - negotiation of PWM channels to use for clock source and clock events, > > because each board can use different channels for PWM outputs, > > > > - code duplication caused by both of the drivers doing mostly the same > > things and or having to parse the same data from device tree, > > > > - both non-DT and DT platforms must be supported, > > > > - how to keep the ability to load PWM driver as a module (or not load it > > at all when PWM is not used on particular board), while retaining > > everything that is needed for the clocksource driver in kernel, > > > > - some platforms can't use PWM timers as system clocksources, while on > > others this is the only timekeeping hardware available. > > > > Hmm. Does anybody have an idea of a better way of implementing this PWM > timer support, which solves the above problems? > > This series is a dependency for moving Universal C210 board to DT-based > description and it's already almost out of time to get this included for > 3.10... > Sorry for not replying earlier. My idea for the register level interface was to create a platform_device for each PWM, e.g. using the mfd_cell infrastructure. You can then pass a "struct regmap" as the platform data for each child of the timer node, and all the DT handling code can stay in the parent driver. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
 |