On Wed, 11 Jan 2017 07:32:11 +0100, Mengdong Lin wrote:
On 01/10/2017 03:09 PM, Takashi Iwai wrote:
On Tue, 10 Jan 2017 07:42:49 +0100, mengdong.lin@linux.intel.com wrote:
+/**
- snd_soc_set_dmi_name() - Register DMI names to card
- @card: The card to register DMI names
- @flavour: The flavour "differentiator" for the card amongst its peers.
- An Intel machine driver may be used by many different devices but are
- difficult for userspace to differentiate, since machine drivers ususally
- use their own name as the card name (short name) and leave the card long
- name blank. To differentiate such devices and fix bugs due to lack of
- device-specific configurations, this function allows DMI info to be used
- as the sound card long name, in the format of
- "vendor.product.version.board"
- (Character '.' are used to separate different DMI fields here).
- This will help the userspace to load the correct UCM (Use Case Manager)
- configuration.
- Possible card long names may be:
- DellInc..XPS139343.01.0310JH
- ASUSTeKCOMPUTERINC..T100TA.1.0.T100TA
- Circuitco.MinnowboardMaxD0PLATFORM.D0.MinnowBoardMAX
- (Please note DMI can also include '.' like"Inc." so you may see double '.
'
- sometimes)
Looking at the examples above, I wonder whether the dot is the best choice as the separator. Might other letters (e.g. ":" or "=") would be clearer? The colon might be bad if it were combined with the alsa-lib plugin syntax, but I guess it won't happen?
Hi Takashi,
I found we cannot use ":" as separator. It's because we want to use the card long name as the name of the directory to store UCM configuration files for this card, and Autoconf cannot support ":" in the directory name.
OK, fair enough.
Both "=" and "-" can work, which would you suggest to use? I've not observed "-" or "=" in DMI fields till now, and I guess "=" is less likely to be used by vendors.
Yes, but OTOH, "=" would become tricky if you want to handle it in a shell script.
One alternative is to use "." or "-" for a separator while converting the existing such letters to a different one like "_".
thanks,
Takashi