On Wed, 6 Oct 2010 14:02:26 -0700, Guenter Roeck wrote: > On Wed, 2010-10-06 at 15:54 -0400, Paul Thomas wrote: > > > No, both of those are runtime options internal to the ads7871, and > > > because we initiate a read by setting that register anyway there isn't > > > any additional setup cost (at least there isn't any spi cost, there is > > > a little additional code in show_voltage). > > > > This isn't a matter of cost, but a matter of maintaining a consistent > ABI. > > A brief look into the datasheet shows that the chip is a generic adc. So > I assume its use is not limited to voltage monitoring, and that you > would in fact expect to change the gain during runtime (ie not only at > system startup). Is this a correct assumption ? This is the problem with having ADC drivers in drivers/hwmon. These are versatile devices, they can be used for voltage monitoring but also for a variety of other things, and the desired interface depends on that. Runtime gain changes is not desirable at all for a voltage monitoring device. A solution to this may be to move the ADC driver itself somewhere else, and have a dummy driver in hwmon/ merely adding a hwmon-style interface on top of the main driver. Other such dummy driver could be written for other use cases of the ADC. I think this is what the s3c-hwmon driver is doing, and maybe others. -- Jean Delvare _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
