Messages in this thread | | | Date | Thu, 17 May 2018 15:04:06 +0200 | From | Andrew Lunn <> | Subject | Re: [PATCH net-next 1/2] net: phy: sfp: make the i2c-bus property really optional |
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On Thu, May 17, 2018 at 02:56:48PM +0200, Antoine Tenart wrote: > Hi Andrew, > > On Thu, May 17, 2018 at 02:41:28PM +0200, Andrew Lunn wrote: > > On Thu, May 17, 2018 at 10:29:06AM +0200, Antoine Tenart wrote: > > > The SFF,SFP documentation is clear about making all the DT properties, > > > with the exception of the compatible, optional. In practice this is not > > > the case and without an i2c-bus property provided the SFP code will > > > throw NULL pointer exceptions. > > > > > > This patch is an attempt to fix this. > > > > How usable is an SFF/SFP module without access to the i2c EEPROM? I > > guess this comes down to link speed. Can it be manually configured? > > > > I'm just wondering if we want to make this mandatory? Fail the probe > > if it is not listed? > > Yes, the other option would be to fail when probing a cage missing the > i2c description. I'd say a passive module can work without the i2c > EEPROM accessible as it does not need to be configured. I don't know > what would happen with active ones.
Hi Antoine
I was thinking about how it reads the bit rate from the EEPROM. From that it determines what mode the MAC could use, 1000-Base-X, 2500-Base-X, etc. Can you still configure this correctly via ethtool, if you don't have the bitrate information?
Andrew
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