On 20120625-16:14, Tomi Valkeinen wrote: > A question about clk_prepare/unprepare, not directly related: let's say > I have a driver for some HW block. The driver doesn't use clk functions, > but uses runtime PM. The driver also sets pm_runtime_irq_safe(). > > Now, the driver can call pm_runtime_get_sync() in an atomic context, and > this would lead to the underlying framework (hwmod, omap_device, I don't > know who =) enabling the func clock for that HW. But this would happen > in atomic context, so the underlying framework can't use clk_prepare. > > How does the underlying framework handle that case? (sorry if that's a > stupid question =). > I think it's a good question! If we're going to call clk_prepare_enable from within a runtime pm callback then I think we'll need to check if _irq_safe() is set and conditionally call only clk_enable in such a case. I'm not a runtime pm expert, but if the driver owns the responsibility of calling pm_runtime_irq_safe then the driver has the proper context to know that it should call clk_prepare BEFORE calling pm_runtime_get_sync. However if some other framework (outside of the driver) calls pm_runtime_irq_safe then it will be difficult for the driver to know what to do... Regards, Mike > Tomi > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
