Hi, On Sun, Mar 20, 2016 at 09:43:11PM +0200, Ivaylo Dimitrov wrote: > On 20.03.2016 07:17, Sebastian Reichel wrote: > >On Sat, Mar 19, 2016 at 10:49:57AM +0200, Ivaylo Dimitrov wrote: > >>On 18.03.2016 17:04, Sebastian Reichel wrote: > >>>On Fri, Mar 18, 2016 at 03:45:26PM +0200, Ivaylo Dimitrov wrote: > >>>>On 18.03.2016 15:36, Sebastian Reichel wrote: > >>>>Regulator is V28_A, which is always-on, so it is enabled no matter what > >>>>probe does. Anyway, I added a various delays after regulator_enable(), to no > >>>>success. > >> > >>I guess we're getting closer - I put some printks in various functions in > >>the twl-regulator.c, here is the result: > >> > >>on power-up: > >> > >>[ 2.378601] twl4030ldo_get_voltage_sel VMMC2 vsel 0x00000008 > >>[ 2.384948] twl4030reg_enable VMMC2 grp 0x00000020 > >>[ 2.408416] twl4030ldo_get_voltage_sel VMMC2 vsel 0x00000008 > >>[ 7.196685] twl4030reg_is_enabled VMMC2 state 0x0000002e > >>[ 7.202819] twl4030reg_is_enabled VMMC2 state 0x0000002e > >>[ 7.209777] twl4030reg_is_enabled VMMC2 state 0x0000002e > >>[ 7.215728] twl4030reg_is_enabled VMMC2 state 0x0000002e > >>[ 7.223205] twl4030reg_is_enabled VMMC2 state 0x0000002e > > > >Ok, so normal power up results in running VMMC2 (always-on works), > >but voltage is not configured correctly. 2.6V is default according > >to the TRM. I think this is a "bug" in the regulator framework. It > >should setup the minimum allowed voltage before enabling the > >always-on regulator. > > > > /sys/kernel/debug/regulator/regulator_summary shows 2850mV for V28_A, so I > would remove the quotes. Also, always-on is because if V28_A regulator is > turned off, there is a leakage through tlv320aic34 VIO. BTW one of the > things I did while trying to find the problem, was to remove that always-on > property from the DTS - it didn't help. Right thinking about it, the voltage must also be configured for the non always-on cases. So it's not a problem with the regulator framework, but with twl-regulator's probe function, that should take care of this. > >In case of the tpa6130a2/tpa6140a2 driver it may also be nice to add > >something like this to the driver (Vdd may be between 2.5V and 5.5V > >according to both datasheets): > > > >if (regulator_can_change_voltage(data->supply)) > > regulator_set_voltage(data->supply, 2500000, 5500000); > > > > and add DT property for that voltage range, as max output power and > harmonics depend on the supply voltage. I guess that's 2nd step. > >>after restart from stock kernel: > >> > >>[ 2.388610] twl4030ldo_get_voltage_sel VMMC2 vsel 0x0000000a > >>[ 2.394958] twl4030reg_enable VMMC2 grp 0x00000028 > > > >I had a quick glance at this. I think stock kernel put VMMC2 > >into sleep mode. Mainline kernel does not expect sleep mode > >being set and does not disable it. > > > > Well, one would think that kernel should not have expectations on what would > be the state of the hardware by the time it takes control over it, but setup > everything needed instead. I thought it's obvious, that this is not the desired behaviour :) > >>[ 2.418426] twl4030ldo_get_voltage_sel VMMC2 vsel 0x0000000a > >>[ 7.186645] twl4030reg_is_enabled VMMC2 state 0x00000020 > >>[ 7.192718] twl4030reg_is_enabled VMMC2 state 0x00000020 > >>[ 7.199615] twl4030reg_is_enabled VMMC2 state 0x00000020 > >>[ 7.205535] twl4030reg_is_enabled VMMC2 state 0x00000020 > >>[ 7.212951] twl4030reg_is_enabled VMMC2 state 0x00000020 > >> > >>I don't see twl4030ldo_set_voltage_sel() for VMMC2(V28_A) regulator, though > >>there are calls for VMMC1 and VAUX3. > > > >I guess that's because the voltage is only configured if at least > >one regulator consumer requests anything specific. > > > > But then the board DTS is simply ignored. Doesn't look good :) > > >>So, it seems to me that V28_A is not enabled or correctly set-up > >>and all devices connected to it does not function. And it looks > >>like even after power-on VMMC2 is not correctly set-up - it is > >>supposed to have voltage of 2.85V (10) but kernel leaves it to > >>2.60V (8). However my twl-fu ends here so any help is appreciated. > > > >So in case of reboot from stock kernel voltage is already configured > >to 2.8V, but it does not work, because of the sleep mode. > > > > Yeah, that sleep is pretty clear, I was rather asking - "any idea how to fix > that?". Or it is someone else expected to fix it? You may have noticed, that I included Mark and Liam. I hope they can give some feedback. I think there are two bugs: 1. twl_probe() should setup a default voltage based on DT information. 2. if regulator is in sleep mode, regulator enable should disable sleep mode. -- Sebastian
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