On 27/06/16 13:11, Linus Walleij wrote: > On Sun, Jun 26, 2016 at 12:21 PM, Jonathan Cameron <jic23@xxxxxxxxxx> wrote: >> On 22/06/16 21:53, Linus Walleij wrote: >>> The calibration data is described as coming from an E2PROM and that >>> means it does not change. Just read it once at probe time and store >>> it in the device state container. Also toss the calibration data >>> into the entropy pool since it is device unique. >>> >>> Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx> >> >> One nitpick inline, but it's minor enough I'm just being grumpy >> about it so don't bother fixing it unless you want to. >> >> On the adding entropy bit, any idea who to sanity check that with? >> It's not something we've done before, so I just want a bit of >> reassurance ideally;) > > I've done it in a few places whenever I ran into device-unique numbers, > actually sensors often have device-unique calibration and are thus well > suited to toss into the entropy pool. > > The data from devices isn't really trusted to increase entropy: it may, > but it's not relied on by the algorithm, just mixed in, see: > http://lwn.net/Articles/507115/ Fair enough then. J > >>> ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf, >>> sizeof(buf)); >>> - >> Good but unrelated change. Should have been in a different patch... > > Dropped unrelated whitespace fix. > > Yours, > Linus Walleij > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
