Hans, Hans Verkuil wrote: > On Wednesday 17 March 2010 20:28:07 Mauro Carvalho Chehab wrote: >> Guennadi Liakhovetski wrote: >> >>> Hi Mauro >>> >>> we just discussed this with Hans on IRC, and if I understood him >>> correctly, he was of the same opinion, that adding such a variable could >>> help. >>> >>> The problem is the following: this automatic selection works in a way, >>> that various bridge drivers select "helper" chip drivers (i2c subdevice >>> drivers" if this autoselection is enabled, e.g. >>> >>> config VIDEO_MXB >>> tristate "Siemens-Nixdorf 'Multimedia eXtension Board'" >>> depends on PCI && VIDEO_V4L1 && I2C >>> select VIDEO_SAA7146_VV >>> select VIDEO_TUNER >>> select VIDEO_SAA711X if VIDEO_HELPER_CHIPS_AUTO >>> select VIDEO_TDA9840 if VIDEO_HELPER_CHIPS_AUTO >>> select VIDEO_TEA6415C if VIDEO_HELPER_CHIPS_AUTO >>> select VIDEO_TEA6420 if VIDEO_HELPER_CHIPS_AUTO >>> >>> With SoC-based set ups this cannot work. The only location where this >>> information is available is platform code under arch/... and selecting >>> these drivers from there would be awkward imho. >> Kconfig works fine if the var is on another place. So, you could do things >> like: >> >> config VIDEO_xxx >> select VIDEO_foo if VIDEO_HELPER_CHIPS_AUTO && ARCH_bar >> >> You may even convert it into dependencies like: >> >> config VIDEO_I2C_foo >> depends on ARCH_bar && config VIDEO_xxx >> default y if VIDEO_HELPER_CHIPS_AUTO > > I2C drivers are NOT dependent on architectures. They can be used anywhere. > >> The depends on syntax generally works better than using select. We've converted >> some select into depends on a few places like tuner, like, for example: >> >> config MEDIA_TUNER_TDA827X >> tristate "Philips TDA827X silicon tuner" >> depends on VIDEO_MEDIA && I2C >> default m if MEDIA_TUNER_CUSTOMISE >> >>> So, for example, we want >>> to put the ak881x video encoder driver under >>> >>> comment "Video encoders" >>> >>> and those drivers are only visible if VIDEO_HELPER_CHIPS_AUTO is >>> unselected, and if it is selected, which it is by default, there is noone >>> to automatically select ak881x. So, I think, the proposed patch is not a >>> work-around, but a reasonable solution for this issue. >> Even the menu being invisible, any of the above logic would work, if you do >> something like: >> >> config VIDEO_AK881X >> depends on ARCH_MX1 && I2C >> default y if VIDEO_HELPER_CHIPS_AUTO && SOC_CAMERA >> >> or: >> >> config SOC_CAMERA >> select VIDEO_AK881X if VIDEO_HELPER_CHIPS_AUTO && ARCH_MX1 > > Same problem here: the architecture does not determine whether this i2c driver > is needed. That is determined by the board definition. I guess the right place > to do this is probably in a 'mach' specific Kconfig like for example > arch/arm/mach-davinci/Kconfig. > > But to be honest, I think that the SoC + VIDEO_HELPER_CHIPS_AUTO combination > is pretty pointless. > > Regards, > > Hans > I've discussed this issue with Guennadi on IRC today. The better seems to just disable or change the default to 'n' for the AUTO/CUSTOMISE options, when CONFIG_EMBEDDED. He's working on a new patch. -- Cheers, Mauro -- 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
