* Kevin Hilman <khilman@xxxxxxxxxx> [131209 08:07]: > Tony Lindgren <tony@xxxxxxxxxxx> writes: > > > * Nishanth Menon <nm@xxxxxx> [131203 17:40]: > >> Due to the cross dependencies between hwmod for automanaged device > >> information for OMAP and dts node definitions, we can run into scenarios > >> where the dts node is defined, however it's hwmod entry is yet to be > >> added. In these cases: > >> a) omap_device does not register a pm_domain (since it cannot find > >> hwmod entry). > >> b) driver does not know about (a), does a pm_runtime_get_sync which > >> never fails > >> c) It then tries to do some operation on the device (such as read the > >> revision register (as part of probe) without clock or adequate OMAP > >> generic PM operation performed for enabling the module. > >> > >> This causes a crash such as that reported in: > >> https://bugzilla.kernel.org/show_bug.cgi?id=66441 > >> > >> When 'ti,hwmod' is provided in dt node, it is expected that the device > >> will not function without the OMAP's power automanagement. Hence, when > >> we hit a fail condition (due to hwmod entries not present or other > >> similar scenario), fail at pm_domain level due to lack of data, provide > >> enough information for it to be fixed, however, it allows for the driver > >> to take appropriate measures to prevent crash. > > > > Kevin, any comments on this one? > > Looks like a good approach to catch these corner cases. > > Acked-by: Kevin Hilman <khilman@xxxxxxxxxx> Kevin, care to apply this directly? Acked-by: Tony Lindgren <tony@xxxxxxxxxxx> -- 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
