On 11/15/2012 04:52 PM, Grant Likely wrote: > On Mon, 12 Nov 2012 23:54:40 +0100, Per Förlin <[email protected]> > wrote: >> On 11/12/2012 04:20 PM, Grant Likely wrote: >>> On Mon, Nov 12, 2012 at 2:59 PM, Per Forlin <[email protected]> >>> wrote: >>>> Add support to extract device name from device tree blob. >>>> If the property "dev-name" is set in the DTS this name will >>>> be used when creating the device. >>>> The auxdata_lookup has precedence and will override >>>> the "dev-name" property. >>> >>> Using a 'dev-name' property has the same problem that the 'cell-index' >>> properties have in that it is encoding part of the global namespace >>> local to the node and it becomes easy to create collisions. Instead of >>> this check to see if one of the properties in /aliases points to the >>> node and use that for the name. >>> >>> g. >>> >> Thanks Grant for your feedback, >> >> Extract from exynos5250.dtsi: >> ----------- >> aliases { >> spi0 = &spi_0; >> spi1 = &spi_1; >> spi2 = &spi_2; >> }; >> >> spi_0: spi@12d20000 { >> ... >> }; >> >> spi_1: spi@12d30000 { >> ... >> }; >> >> spi_2: spi@12d40000 { >> ... >> }; >> --------------- >> >> Alias refers to the device node. The device node is not aware of the alias. >> >> How to get a device name from the aliases. >> 1. Traverse all aliases for each device node (time consuming if there are >> many aliases) >> 2. Make a new function of_alias_get_name(), today there is only >> of_alias_get_id() >> 3. The functionality of setting device_name based on alias name needs to be >> optional because one may want to use aliases without changing the name of >> the device. >> All this is feasible but perhaps not optimal. >> >> I don't really see how come name space is a big issue in this case. The name >> space of "dev-name" is local to the device node. A child device node can use >> the same dev-name as the parent (unless I'm mistaken which happens quite >> often). Introducing yet another property name pollutes the name space of the >> device node. Still I think the pros are stronger than the cons. >> >> Do you still prefer to use the name of the Alias? Could you please elaborate >> a bit more how this can be done in practice? >> I would agree with you if there was a reference from the device node to the >> alias. > > Oh, I see what you're trying to do. As Lee pointed out you're trying to > make the Linux internal way of matching up clocks and regulators happy. > That is very much a Linux-kernel internal thing and should be solved in > the kernel. Trying to solve it with fixed names in the device tree will > cause problems down the road. > > I though you were wanting to have logical names for the devices that > make sense to the user which is how aliases is used now. > > So, no, don't do this. > > g. > Hi,
I came to the same conclusion when I dag into it some more. I replied to my own comment and concluded (https://lkml.org/lkml/2012/11/13/309). The solution is to move clocks and regulators into the DTS. When this is done there will be no need for setting a specific device-name (all those auxdata_lookup can be removed) BR Per -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
