Messages in this thread | | | Date | Fri, 15 Apr 2016 22:01:52 +0530 | From | Laxman Dewangan <> | Subject | Re: [PATCH 6/7] pinctrl: tegra: Add DT binding for io pads control |
| |
On Friday 15 April 2016 10:05 PM, Stephen Warren wrote: > On 04/12/2016 08:56 AM, Laxman Dewangan wrote: >> NVIDIA Tegra210 supports the IO pads which can operate at 1.8V >> or 3.3V I/O voltage levels. Also IO pads can be configured for >> power down state if it is not in used. SW needs to configure the >> voltage level of IO pads based on IO rail voltage and its power >> state based on platform usage. >> >> Add DT binding document for detailing the DT properties for >> configuring IO pads voltage levels and its power state. > > I hope that we only intend to use this in the case where Linux must > make dynamic changes to the IO voltage (e.g. SD cards switching > between speeds). > > All static settings, and good boot defaults, should be set up by > system FW. Perhaps not all FW does this on Tegra210 platforms:-( I > hope that on future chips, the same FW that sets up the static pinmux > sets up the static IO voltage configuration, in exactly the same way.
Exactly yes.
| |