On 09/10/2013 06:13 PM, Mark Brown wrote: > * PGP Signed by an unknown key > > On Tue, Sep 10, 2013 at 01:39:59PM +0800, Wei Ni wrote: > >> I think the device need time to wait stable after power on, but it's >> difficult to get an exact delay value, and this delay may also relate >> with platform design, so how about to add a optional property in the DT >> node, such as "power-on-delay-ms" ? > > This is something you should *really* be able to get from the datasheet > for the part - this sort of stuff has to be documented for hardware to > be used robustly. It seems entirely possible that you are working > around an issue with the regulator driver you are using not correctly > providing its ramp time here. On my platform, it use palmas-regulator.c, ldo6 for this lm90 power rail. I checked this driver, it will handle ramp_delay except LDOx. Since I'm not familiar with this palmas device and driver, so do you mean I can set regulator-ramp-delay property in the DT for ldo6, but I really don't know what value should I set :( Thanks. Wei. > > * Unknown Key > * 0x7EA229BD > -- 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
