On Wed, Feb 11, 2009 at 05:43:29AM -0200, Mauro Carvalho Chehab wrote: > On Tue, 10 Feb 2009 21:50:16 -0600 > David Engel <david@xxxxxxxxxx> wrote: > > MythTV eventually worked too, but I had to do the > > "unload/reload modules and run tvtime" procedure I reported earlier > > when I tried Hans' kworld tree. > > Maybe this is a race condition I have here with tda1004x. With tda1004x, the i2c > bus shouldn't be used by any other device during the firmware transfers, > otherwise the firmware load will fail, and tda1004x goes into an unstable > state. With this device, it even affects all subsequent i2c acesses. The only > alternative to recover tda1004x is to reboot the card (e. g. with my cardbus > device, I have to physically remove it and re-insert). > > What happens is that some softwares (including udev) open the device, and send > some VIDIOC_G_TUNER in order to check some tuner characteristics. However, this > command generates some i2c transfers, to retrieve signal strength. If this > happens while the firmware is being loaded, the bug occurs. > > In order to fix, a careful review of all locks on the driver is needed. We will > likely need to change the demod interface for the boards that have this > trouble, in order to be aware of when a firmware transfer started. > > This lock review is currently on my TODO list. > > To be sure that this is the case, could you please add this on > your /etc/modprobe (or at a file inside /etc/modprobe.d): > > options nxt200x debug=1 > options tuner-simple debug=1 > options tuner debug=1 > options dvb-core frontend_debug=1 > > And test again, sending us the produced logs when the device works and when it > breaks. I guess we'll discover some tuner dmesg's in the middle of the firmware > load sequence. I will do this, but it will be tomorrow evening before I can get to it. David -- David Engel david@xxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
