On 12/17/2013 03:28 PM, Mark Brown wrote: > On Tue, Dec 17, 2013 at 03:20:35PM -0700, Stephen Warren wrote: > >> The Tegra clocking architecture has a shared audio PLL that provides >> clocks to the various IO controllers (I2S, AC'97, S/PDIF). In order to >> allow multiple IO controllers to be in use at once, a single SW entity >> has to manage the clocks, so that it can configure the audio PLL, rather >> than having each individual IO controller attempt to assert ownership on >> the shared resource. The centralized PLL management needs to switch the >> PLL rate between 2 different values for 48-/44.1KHz-based audio for >> example, and deny requests to switch if already-active audio is running >> at the other rate. > >> So yes, I think doing this all in the machine driver is the best thing. > > How does doing this in the machine driver help here? The machine driver > isn't going to be any more coordinated with other machine drivers than > the controller is. There would only be one machine driver loaded at a time. It should provide top-level control over all the audio paths in the Tegra audio subsystem. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
