Messages in this thread | | | From | Christian Eggers <> | Subject | Re: [PATCH] eeprom: at25: set minimum read/write access stride to 1 | Date | Tue, 28 Jul 2020 14:03:30 +0200 |
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On Tuesday, 28 July 2020, 13:20:15 CEST, David Laight wrote: > From: Christian Eggers > > > &spi { > > .... > > fram: fram@0 { > > ... > > mac_address_fec2: mac-address@126 { > > reg = <0x126 6>; > > }; > > ... > > }; > > }; > > > Hmmmm.... the 'stride' only constrains the alignment of 'cells'. > (ie address ranges from the device tree.)
My mac-address is not aligned to 4 bytes...
> It looks as though you can open the entire NVMEM device and > then do reads from byte offsets. > The 'stride' and 'word_size' are then not checked!
When I set back the stride to 4, I get the following errors: [ 6.998788] 000: nvmem spi0.00: cell mac-address unaligned to nvmem stride 4 [ 6.998902] 000: at25: probe of spi0.0 failed with error -22 ... [ 7.146454] 000: fec 20b4000.ethernet: Invalid MAC address: 00:00:00:00:00:00 [ 7.146480] 000: fec 20b4000.ethernet: Using random MAC address: 6e:9d:37:49:6d:15
> Actually it might be that before 01973a01f9ec3 byte aligned > 'cells' were allowed.
I use linux-5.4.x (latest), the mentioned patch has been included long time ago.
regards Christian
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