Am 2013-11-28 10:49, schrieb Lucas Stach: > Am Mittwoch, den 27.11.2013, 10:13 -0700 schrieb Stephen Warren: >> On 11/26/2013 04:45 PM, Stefan Agner wrote: >> > Set the requested SM2 voltage to the correct value of 1.8V. The value >> > before used to work on TPS658623 since the driver applied a wrong >> > voltage table too. However, the TPS658643 used on newer devices uses >> > yet another voltage table and those broke that compatibility. The >> > regulator driver now has the correct voltage table for both regulator >> > versions and those the correct voltage can be used in this device >> > tree. >> >> One thing you haven't called out explicitly here is that this series is >> an incompatible change to the DT, since the old buggy driver used to >> allow old buggy DT content to accidentally work. >> > The current (wrong and potentially dangerous) DT content only worked on > the engineering sample models. So this change definitely does improve > the situation, even with the risk of breaking a small fraction of > working boards. On the released modules, the current value ends in a freeze during boot-up (since the wrong voltage table results in a too low voltage). When I use 1.8V in the device tree, the old drivers refuses to set any voltage. The regulators default/bootloader settings work then better than the wrongfully applied values (tested on a new device). The probe just fails: [ 0.243864] tps6586x-regulator tps6586x-regulator: failed to register regulator REG-SM_2 [ 0.244317] tps6586x-regulator: probe of tps6586x-regulator failed with error -22 So, for newer modules, the incompatible 1.8V DT results in a successful boot. Since we don't have a regulator driver at all, likely other things are broken at that situation... -- Stefan -- 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
