On Thu, Jun 2, 2011 at 19:10, Kevin Hilman <khilman@xxxxxx> wrote: > "Menon, Nishanth" <nm@xxxxxx> writes: > >> On Thu, Jun 2, 2011 at 18:45, Kevin Hilman <khilman@xxxxxx> wrote: >>> Nishanth Menon <nm@xxxxxx> writes: >>> >>>> Due to a TRM bug, the current code assumes that channel0(core) is the default >>>> channel. With the additional explanation provided by the hardware team, it is >>>> clear that PRM_VC_CFG_CHANNEL register allows for flexibility of configuring >>>> for various PMIC configurations. For example, the I2C slave address on TWL6030 >>>> when using 4430 configuration could potentially use the same slave address for >>>> all domains, while in 4460 configuration, we drive MPU using TPS; Core and IVA >>>> using TWL6030. To allow this flexibility, we state in existing parameters using >>>> a flag to indicate usage of default channel. >>>> >>>> In addition, the TRM update clears up the confusion on the fact that MPU is >>>> infact the default channel on OMAP4. >>>> >>>> We update the same here. >>>> >>>> Signed-off-by: Nishanth Menon <nm@xxxxxx> >>> >>> There's too much going on in this patch not described in the changelog >>> (extra error checking, volt & cmd reg checking etc.) >>> >>> Also, I don't like the USE_DEFAULT_CHANNEL_I2C_PARAM, mainly because it >>> adds clutter without any obvious value. To me, zero is a perfectly good >>> value to signify "use default channel value", especially since that's >>> the value used by the hardware. >> The reason is that 0 is a valid i2c register address. 8 bits is used >> in VC and I wanted one bit which was further away, hence the 16 bit. >> The usage could be that in .volt_reg_addr or in .cmd_reg_addr I could >> set this up with the macro. and bingo, we use the default domain's >> configuration. >> >> This is esp useful if we had a single pmic reg for all domains.. I >> mean the VC design allows for it, even though we dont use it >> currently. > > OK. > > See, it's easy to convince me that something is needed/useful. Of > course, I prefer to be conviced by the changelog. :) > > Please make this feature into a dedicated patch with an appropriately > descriptive changelog. Thanks. Yes, I agree. it probably is a better idea to break this thing up - I guess I was a bit lazyish considering these were targetted to be squashed.. not in the next series :) > >>> >>> Incidentally, adding this doesn't actually change current behavior. >>> Currently, I use zero (an unconfigured value in the VC settings) to >>> signify it should use default settings. In your patch, you defined >>> USE_DEFAULT_CHANNEL_I2C_PARAM as 0x10000 (17 bits) but assign it to 16 >>> bit fields, which means they are just set to zero. :) >> >> >>> So rather than take this patch, I'm just going to fold the following >>> diff into "OMAP3+: VC: abstract out channel configuration" in voltdm_b. >>> I'll also update the changelog noting that the TRM is wrong here in that >>> it describes CORE as the default channel when it's in fact MPU. >> >> I intend to post a new series including my PMIC changes as well early >> next week(mondayish hopefully). Can we hold off review of any further >> of my voltage fixes patches till then? >> > > Sure. It's the first time anyone as asked me not to review patches. :) > I'll gladly comply. > > I've already folded the minimal change I proposed into the original > patch locally, and will push updated voltdm_* branches by the end of > today. :) Thanks. I will rework the patches and line up a series from cpufreq and voltage domain perspective in the upcoming days.. Regards, Nishanth Menon -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
