On 28.11.2017 12:44, Bartosz Golaszewski wrote: > 2017-11-28 11:25 GMT+01:00 Andy Shevchenko <andy.shevchenko@xxxxxxxxx>: >> On Mon, Nov 27, 2017 at 11:06 PM, Bartosz Golaszewski <brgl@xxxxxxxx> wrote: >>> There's an ilog2() expansion in AT24_DEVICE_MAGIC() which rounds down >>> the actual size of EUI-48 byte array in at24mac402 eeproms to 4 from 6, >>> making it impossible to read it all. >>> >>> Fix it by manually adjusting the value in probe(). >>> >>> This patch contains a temporary fix that is suitable for stable >>> branches. Eventually we'll probably remove the call to ilog2() while >>> converting the magic values to actual structs. >> >>> + /* >>> + * REVISIT: the size of the EUI-48 byte array is 6 in at24mac402, while >>> + * the call to ilog2() in AT24_DEVICE_MAGIC() rounds it down to 4. >>> + * >>> + * Eventually we'll get rid of the magic values altoghether in favor of >>> + * real structs, but for now just manually set the right size. >>> + */ >>> + if (chip.flags & AT24_FLAG_MAC && chip.byte_len == 4) >> >> I didn't check, but do we need to test for len == 4 at all? >> >>> + chip.byte_len = 6; >> >> -- >> With Best Regards, >> Andy Shevchenko > > Yes, because the fix is only relevant for at24mac402 whose MAC byte > array is 6 bytes long, while the one in at24mac602 is 8 bytes and the > driver doesn't truncate the byte_len for it. >From my point of view, I think all chips in at24_ids[] array should be checked about restrictions regarding the size truncation (especially the ones from the initial commit: "2b7a5056a0a7ff17d5d2 i2c: New-style EEPROM driver using device IDs" which introduces AT24_DEVICE_MAGIC() macro) and if none of them has such restrictions we should get rid of the ilog2() restrictions. Just my 2 cents... Claudiu > > Thanks, > Bartosz >
