Hi, On 22.09.21 15:03, Srinivas Kandagatla wrote: > > > On 22/09/2021 13:58, Ahmad Fatoum wrote: >> Hi Srini, >> >> On 22.09.21 14:49, Srinivas Kandagatla wrote: >>> >>> >>> On 22/09/2021 13:31, Ahmad Fatoum wrote: >>>>>> >>>>>> On 08.09.21 12:02, Joakim Zhang wrote: >>>>>>> From: Srinivas Kandagatla<srinivas.kandagatla@xxxxxxxxxx> >>>>>>> >>>>>>> Some of the nvmem providers encode data for certain type of nvmem cell, >>>>>>> example mac-address is stored in ascii or with delimiter or in reverse order. >>>>>>> >>>>>>> This is much specific to vendor, so having a cell-type would allow nvmem >>>>>>> provider drivers to post-process this before using it. >>>>>> I don't agree with this assessment. Users of the OCOTP so far >>>>>> used this specific encoding. Bootloaders decode the OCOTP this way, but this >>>>>> encoding isn't really an inherent attribute of the OCOTP. A new NXP SoC >>>>>> with a different OTP IP will likely use the same format. Users may even >>>>>> use the same format on an EEPROM to populate a second off-SoC interface, .. etc. >>>>>> >>>>> That is okay. >>>> How would you go about using this same format on an EEPROM? >>> >>> Am guessing that by the time there are more users for such formats, those post-processing functions should be converted into some library functions. >> >> User A wants to reverse bytes in MAC address. User B stores it in ASCII. >> Both use the exact same EEPROM. How could this ever work when the >> encoding decision is left to the EEPROM driver? > > User A and B should mention about this encoding information in there NVMEM provider bindings. > > Based on that specific post-processing should be selected. So instead of just compatible = "atmel,at24c16"; there will be compatible = "user-A,my-eeprom", "atmel,at24c16"; and compatible = "user-B,my-eeprom", "atmel,at24c16"; and they each need to patch the at24 driver to call one of the common library functions? > > --srini >> > >>> >>> --srini >>> >>>> >>>>>> I'd thus prefer to not make this specific to the OCOTP as all: >>>>>> >>>>>> * #define NVMEM_CELL_ENCODING_MAC_ADDRESS_IMX /* ... */ >>> >> >> > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
