On Fri, Jul 11, 2014 at 08:21:27PM +0300, Tuomas Tynkkynen wrote: > > > On 11/07/14 20:08, Andrew Bresticker wrote: > >On Fri, Jul 11, 2014 at 9:48 AM, Tuomas Tynkkynen <ttynkkynen@xxxxxxxxxx> wrote: > >> > >> > >>On 11/07/14 19:28, Andrew Bresticker wrote: > >>> > >>>On Thu, Jul 10, 2014 at 2:42 PM, Tuomas Tynkkynen <ttynkkynen@xxxxxxxxxx> > >>>wrote: > >>>> > >>>>The DFLL is the main clocksource for the fast CPU cluster on Tegra124 > >>>>and also provides automatic CPU rail voltage scaling as well. The DFLL > >>>>is a separate IP block from the usual Tegra124 clock-and-reset > >>>>controller, so it gets its own node in the device tree. > >>> > >>> > >>>>diff --git > >>>>a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt > >>>>b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt > >>> > >>> > >>>>+- nvidia,pmic-voltage-table: Array of 2-tuples. Each entry should have > >>>>the > >>>>+ form <register-value voltage-in-uV>, indicating the register value > >>>>that > >>>>+ needs to be programmed to the PMIC for changing the VDD_CPU voltage to > >>>>+ the specified voltage. The table must be in ascending order by the > >>>>voltage. > >>> > >>> > >>>Instead of listing the register values for each voltage in the DT, > >>>can't you use regulator_list_voltage() to create this map? > >>> > >> > >>I don't see a way to get the register values that way, unless we assume that > >>the mapping is linear and doesn't have holes. > > > >Hmm... I guess if you don't assume it's linear and continuous you'd > >have to iterate over all 256 selectors. > > > > I don't think we can assume that each selector maps to a concrete register > value, though I'm not sure. include/linux/regulator/driver.h documents for > @list_voltage "Selectors range from zero to one less > regulator_desc.n_voltages." but maybe the consumer API could take different > values. I don't think the regulator API makes any guarantees that the selector corresponds to a register value. Adding Mark Brown, maybe he can help figure out the best way to do this. Thierry
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