Hi Heikki, > -----Original Message----- > From: Krogerus Heikki (Nokia-MS/Helsinki) > Sent: 10. maaliskuuta 2011 17:22 > To: Jokiniemi Kalle (Nokia-MS/Tampere) > Cc: balbi@xxxxxx; linux-usb@xxxxxxxxxxxxxxx > Subject: Re: [RFC PATCH 0/1]: Fix ISP1707 suspend on n900 > > Hi, > > On Thu, Mar 10, 2011 at 10:27:06AM +0000, ext kalle.jokiniemi@xxxxxxxxx > wrote: > > > On Thu, Mar 10, 2011 at 12:00:45PM +0200, Kalle Jokiniemi wrote: > > > > I'm currently working on fixing the power management issues in > > > > N900 MeeGo release. There is one big power consumer occurring > > > > which is the > > > > ISP1707 USB tranceiver. It is taking ~14mA power all the time > > > > regardless of cable being plugged in the device or not. > > > > > > > > I got the problem fixed with following patch in the MeeGo 2.6.37 > > > > based kernel, but the same fix does not seem to help with upstream > linux-usb. > > > > > > > > Do you have any ideas why it did not work, or how we could make > > > > the suspending work in upstream linux-usb? > > > > > > No ideas, sorry. But when you say that it doesn't work, what do you > mean? > > > Did you very the bit got written ? What happens to power consumption ? > > > Never drops ? > > > > The power consumption never dropped. Did not check any registers, I'm > > not too familiar with the musb driver. But I'll put in some debug code > > to see how the suspend bit is set. > > I don't know why the isp1707 does not go into low power mode in this case, > but on RX51 the CHIP_SEL pin is connected to a gpio. I would use that always > when there is no need for USB (cable unplugged or dedicated charger). By > disabling the chip select it will go into power off mode and consume even > less then in low power mode. Thanks for the pointer! I'll look into it. I'm fixing this as part of getting the N900 power management back into shape for MeeGo.com. Relevant bugs here, in case you guys are interested: https://bugs.meego.com/show_bug.cgi?id=14370 https://bugs.meego.com/show_bug.cgi?id=7790 There is also a problem with USB eating a lot of current from the PMIC (TWL5030) after boot, though It seemed to not be the case with upstream linux-usb, so need to just find the right patch to backport to our meego kernel. That bug is here: https://bugs.meego.com/show_bug.cgi?id=14369 - Kalle > > -- > heikki -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
