* Dave Gerlach <d-gerlach@xxxxxx> [140423 10:25]: > On 04/23/2014 09:59 AM, Tony Lindgren wrote: > >* Dave Gerlach <d-gerlach@xxxxxx> [140422 12:53]: > >>On 04/22/2014 02:01 PM, Tony Lindgren wrote: > >>>* Dave Gerlach <d-gerlach@xxxxxx> [140422 11:52]: > >>>>This patch, along with patch here [1], fixes boot for am437x-gp-evm. The > >>>>bootloader configures gpio5_7 to control the DDR3 termination regulator, > >>>>the linked patch prevents that gpio bank from being reset and losing > >>>>the previously configured state, and this patch binds the gpio to a > >>>>regulator so the kernel is aware of the state of the gpio. > >>>> > >>>>[1] https://www.mail-archive.com/linux-omap@xxxxxxxxxxxxxxx/msg102941.html > >>> > >>>Setting up the GPIO regulator makes sense to me. But the hack in the > >>>link above is potentially a nasty time bomb for anybody trying to > >>>use GPIO bank 5 on that board. > >>> > >>>What tests have been done that the GPIO bank behaves properly when > >>>it's not reset? > >> > >>We've been using this configuration on this board for a while without any > >>apparent issues. Also, am335x-evmsk already uses the same idea for the VTT > >>regulator on board from commit 6046adb6ad701026c10adeac8d6a4138895f12e5 > >>[ARM: dts: am335x-evmsk: Do not reset gpio0] and I am unaware of any issues > >>with that either. > > > >OK. Do you have other GPIOs in use as interrupts for devices in these > >banks and do they work fine? > > I dont see any interrupts in use from gpio5 bank but as a quick test if I > add ti,no-reset-on-init to gpio3 and gpio4 I see no issue with matrix-keypad > operation which uses gpios from each of those banks. OK thanks for testing. I'll apply the ti,no-reset-on-init patch from [1] above into omap-for-v3.15/fixes-v2. The regulator patch can wait for v3.16, and should be also implemented for the am335x-evmsk the same way, so maybe add that too to your patch? > >Also, can you please test to make sure this works with the most recent > >Javier's GPIO patches that had the issue of not booting on am335x-evmsk? > > > > Yes, when using Javier's patches in addition to this patch [1], which was > found to be necessary through this discussion [2], the AM437x GP EVM boots > fine with linux-next with my regulator patch and gpio5 no reset patch > applied. OK good to hear. Tony > [1] https://patchwork.kernel.org/patch/4041881/ > [2] http://marc.info/?t=139817273800014&r=1&w=2 > > >Regards, > > > >Tony > > > -- 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
