Jean Delvare wrote: > On Wed, 16 Jul 2008 11:50:15 +0200, Wolfgang Grandegger wrote: >> Jean Delvare wrote: >>> The problem is that at this point in time, only a couple hwmon drivers >>> have been converted to new-style i2c. So, dropping the I2C_CLASS_HWMON >>> would break most systems. >>> >>> I have a set of patches converting most hwmon drivers to new-style i2c. >>> I plan to send it to Linus later today. Once all drivers are converted, >>> everyone can start adding device definitions to platform code. And only >>> once this is done for all platforms, you may remove I2C_CLASS_HWMON >>> from the i2c-mpc driver. >> Of course. >> >>> But even then, you can't exclude the possibility that some people want >>> to keep relying on the auto-detection mode. In that case, the setting >> I understood that this is only true for the HWMON devices. Why the >> special treatment? > > Not really. There are other I2C_CLASS_* flags, just check <linux/i2c.h>. > > What makes hwmon a bit different is the historical context. Originally, > the hwmon drivers were written for PCs, which have no per-system > platform code, so declaring the devices was simply not an option. > Additionally, i2c was maintained as part of the lm-sensors project > itself. This determined the probe-everything approach that has ruled > the i2c subsystem until recently. I've spent (with a few other > developers) the past few years drawing a clear separation between i2c > and hwmon, and now making it possible to declare i2c devices where > possible. This is a lot of work if you want to do this without breaking > any system out there (which is my case.) I can image. Thanks for the explanation. > >>> of the I2C_CLASS_HWMON flag should become an attribute of each i2c-mpc >>> device. >> Yep, as probing might not be acceptable in some cases, I makes sense to >> add a property to suppress probing: > > It'd rather make no-probing the default if possible. My understanding > is that all systems using i2c-mpc should have proper platform data. Yep, unfortunately, HWMON devices are not defined in most cases. > But then again, that's not really my business. The decision is left to > the actual users of this i2c bus driver. A RFC patch is in preparation. Wolfgang.
