On Thu, Sep 24, 2015 at 04:57:37AM -0700, Shawn Guo wrote: > On Thu, Sep 24, 2015 at 01:43:24PM +0800, Shengjiu Wang wrote: > > On Wed, Sep 23, 2015 at 08:33:41AM -0700, Shawn Guo wrote: > > > On Tue, Sep 15, 2015 at 06:01:01PM +0800, Shengjiu Wang wrote: > > > > As spdif driver will register SPDIF clock to regmap, regmap will do > > > > clk_prepare in init function, so SPDIF clock is prepared in probe, then its > > > > root clock (pll clock) is prepared also, which cause the arm can't enter > > > > low power mode. > > > > > > Can you help me understand why ARM cannot enter low power mode when pll > > > clock is prepared? > > > > > > Shawn > > Hi Shawn > > > > In i.mx clock framework, when pll clk is prepared, it will be powerup. when > > enterring low power idle mode, the powerdown bit is checked, when pll is not > > powerdown state, chip will not enter low power idle mode. > > So this is not a SPDIF specific problem, and any device driver preparing > its clock that is a child of pll clock will run into this problem, > right? If so, we should purchase a more generic solution than such > device specific one. > > Shawn Hi shawn SPDIF_GCLK is also spdif's clock, it use a same enable bit with SPDIF_ROOT_CLK, We didn't separate them in clock tree before. I can't find a generic solution. But anyway if there is a solution or not, I think we'd better to separate them. best regards wang shengjiu -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
