Messages in this thread | | | Date | Mon, 21 Jan 2013 08:25:59 +0100 | Subject | Re: [RFC] Creating an eeprom class | From | Thomas De Schampheleire <> |
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On Sun, Jan 20, 2013 at 11:39 PM, Greg KH <gregkh@linuxfoundation.org> wrote: > On Sun, Jan 20, 2013 at 07:08:28PM +0100, Thomas De Schampheleire wrote: >> [plaintext and fixed address of David Brownell] > > David passed away a year or so ago, so that's really not going to help :(
So sorry to hear that, I was not aware...
> >> Hi, >> >> Several of the eeprom drivers that live in drivers/misc/eeprom export >> a binary sysfs file 'eeprom'. If a userspace program or script wants >> to access this file, it needs to know the full path, for example: >> >> /sys/bus/spi/devices/spi32766.0/eeprom >> >> The problem with this approach is that it requires knowledge about the >> hardware configuration: is the eeprom on the SPI bus, the I2C bus, or >> maybe memory mapped? >> >> It would therefore be more interesting to have a bus-agnostic way to >> access this eeprom file, for example: >> /sys/class/eeprom/eeprom0/eeprom >> >> Maybe it'd be even better to use a more generic class name than >> 'eeprom', since there are several types of eeprom-like devices that >> you could export this way. > > Does all of the existing "eeprom" devices use the same userspace > interface? If so, yes, having a "class" would make sense.
All but one do. That one (eeprom_93cx6.c) exports its read/write functions to other kernel code, and is used in several wireless/ethernet drivers.
> >> Or should we rather hook the eeprom code into the mtd subsystem? > > Why mtd?
Because an eeprom is a piece of memory. Maybe mtd is overkill in term of the operations supported, but from a high-level perspective an eeprom is a memory technology device, right?
Thanks, Thomas
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