On Wed, Oct 28, 2015 at 09:08:02AM -0700, Ray Jui wrote: > On 10/28/2015 2:06 AM, Anup Patel wrote: > > > >I think for a newly created OF devices the Linux device driver framework will > >match the platform drivers in the order in which they are registered by module > >init functions. Now the order of module init function calls will be based how > >the .initcall section is formed by linker and order in which objects are linked. > > > > Yes, what you said is my understanding as well, but then here is the > mystery. This is the link order in brcmnand/Makefile: > > 1 # link order matters; don't link the more generic brcmstb_nand.o > before the > 2 # more specific iproc_nand.o, for instance > 3 obj-$(CONFIG_MTD_NAND_BRCMNAND) += iproc_nand.o > 4 obj-$(CONFIG_MTD_NAND_BRCMNAND) += bcm63138_nand.o > 5 obj-$(CONFIG_MTD_NAND_BRCMNAND) += brcmstb_nand.o > 6 obj-$(CONFIG_MTD_NAND_BRCMNAND) += brcmnand.o > > Based on the order above, probe from iproc_nand should always be > called first if a matching compatible string is found. If so, then > why having both compatible strings "brcm,brcmnand" and > "brcm,nand-iproc" causes issues for NS2 (I remember it broke > smoketest in the past when you submitted the change)? I'm not saying > we should have "brcm,brcmnand" for iProc devices, but I don't get > why it would cause any issue. FWIW, the above hack doesn't do anything if these are built as modules, AFAICT. So I guess udev's (or similar) module rules would be another point of failure here? Not that any of us probably care too much about this driver as a module, but just throwing it out there... I have a feeling we'll have to solve this locally, by avoiding having "independent" drivers handling similar compatible properties, as I expect (despite our expectation that compatible ordering should matter) this problem will not be solved any time soon in the generic infrastructure. Or we can just use a hack (as Anup is doing) to leave off the "brcm,brcmnand" compatibility property. Unless someone has brilliant ideas, I guess we go with Anup's hack for now. Brian -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
