[PATCH] ARM: tegra: add "nor-jedec" flash compatible binding
From: Stephen Warren <hidden>
Date: 2015-05-08 21:04:26
Also in:
linux-devicetree, linux-sh, linux-spi, linux-tegra
On 05/08/2015 02:57 PM, Geert Uytterhoeven wrote:
On Fri, May 8, 2015 at 8:43 PM, Brian Norris [off-list ref] wrote:quoted
On Fri, May 08, 2015 at 10:00:12AM -0600, Stephen Warren wrote:quoted
On 05/08/2015 12:21 AM, Rafa? Mi?ecki wrote:quoted
Starting with commits 8ff16cf ("Documentation: devicetree: m25p80: add "nor-jedec" binding") 1103b85 ("mtd: m25p80: bind to "nor-jedec" ID, for auto-detection") we have "nor-jedec" binding indicating support for JEDEC identification.The documentation looks quite incomplete. "nor-jedec" sounds like it's intended to be something generic. As such, it should be documented in e.g. Documentation/devicetree/bindings/mtd/nor-jedec.txt, not buried in one particular flash device's binding. If it's not intended to be generic, why isn't the existing "winbond,w25q32dw" enough?It is generic, though there are plenty of additional manufacturer/device pairs that could go on top of it. m25p80 was (one of?) the first supported, so the naming has been based on legacy, and we're in the process of unwinding a bit of that. If it helps, we could move the doc to .../mtd/spi-nor,nor-jedec.txt or something like that.quoted
Equally, "nor-jedec" doesn't sound like the right name. It doesn't differentiate between SPI and parallel NOR flash, which presumably need different compatible values, since the programming model is quite different, and the compatible value is supposed to define/imply the SW-visible programming model.It's definitely for SPI only. There was much discussion about this a few months back. Somewhere along the way, it was mentioned that the context (SPI slave is a child of SPI master) would make this clear. I'm still not sure why we didn't end up with something more descriptive, though, like "spi-nor,nor-jedec".What about "jedec,spi-nor"?
That seems unique enough to me, or the options below if they're actually applicable.
Is this "SERIAL FLASH DISCOVERABLE PARAMETERS (SFDP)"? https://www.jedec.org/standards-documents/docs/jesd216b (Don't have time to register with jedec now...) If yes, "jedec,sfdp"? "jedec,jesd216b"?