Quoting Stephen Boyd (2013-07-25 09:45:42) > On 07/25, Tomasz Figa wrote: > > On Wednesday 24 of July 2013 17:43:32 Stephen Boyd wrote: > > > Some of Qualcomm's clocks can change their parent and rate at the > > > same time with a single register write. Add support for this > > > hardware to the common clock framework by adding a new > > > set_rate_and_parent() op. When the clock framework determines > > > that both the parent and the rate are going to change during > > > clk_set_rate() it will call the .set_rate_and_parent() op if > > > available and fall back to calling .set_parent() followed by > > > .set_rate() otherwise. > > > > This is strange. Does you hardware support switching parent and rate > > separately or you always need to set both and so all the fuss here? > > It supports setting the parent or setting the rate, or setting > both at the same time. I think that setting parent and rate at the same time is a common enough case to merit handling it in the clock core. Probably this design will become more common in time. Regards, Mike > > > > > If the latter is the case, then maybe you can simply keep parent index and > > rate cached inside driver data of your clock driver and use them on any > > .set_rate() or .set_parent() calls? > > This will not work. In fact, doing that would cause us to > overclock hardware for a short time between switching the parent > and the rate. > > -- > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, > hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
