On Tue, 7 Jan 2025, Thomas Weißschuh wrote: > On 2025-01-07 15:18:21-0600, Mario Limonciello wrote: > > On 1/7/2025 14:50, Thomas Weißschuh wrote: > > > On 2025-01-07 13:29:08-0600, Mario Limonciello wrote: > > > > On 1/7/2025 11:05, Thomas Weißschuh wrote: > > > > > The driver showcases the use of the new subsystem API. > > > > > > > > > > Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx> > > > > > --- > > > > > drivers/platform/x86/Kconfig | 12 ++++ > > > > > drivers/platform/x86/Makefile | 1 + > > > > > drivers/platform/x86/firmware_attributes_test.c | 78 +++++++++++++++++++++++++ > > > > > 3 files changed, 91 insertions(+) > > > > > > > > > > diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig > > > > > index 0258dd879d64be389f4dd9bc309fe089f23cc798..2a0e828657d2f07074944d6c42dc204fc8825a42 100644 > > > > > --- a/drivers/platform/x86/Kconfig > > > > > +++ b/drivers/platform/x86/Kconfig > > > > > @@ -1065,6 +1065,18 @@ source "drivers/platform/x86/x86-android-tablets/Kconfig" > > > > > config FW_ATTR_CLASS > > > > > tristate > > > > > +config FW_ATTR_TEST > > > > > + tristate "Firmware attribute test driver" > > > > > + select FW_ATTR_CLASS > > > > > + help > > > > > + This driver provides a test user of the firmware attribute subsystem. > > > > > + > > > > > + An instance is created at /sys/class/firmware-attributes/test/ > > > > > + container various example attributes. > > > > > + > > > > > + To compile this driver as a module, choose M here: the module > > > > > + will be called firmware_attributes_test. > > > > > + > > > > > > > > I think if you're going to be introducing a test driver it should be > > > > compliant to what's in sysfs-class-firmware-attributes so that when it's > > > > inevitably copy/pasted we end up with higher quality drivers. > > > > > > > > That is you need at a minimum 'type', 'current_value', 'default_value', > > > > 'display_name' and 'display_name_language_code'. Then individual types > > > > employ additional requirements. > > > > > > > > I see 'type', 'current_value', and 'default_value, but I don't see > > > > 'display_name' or 'display_name_language_code' here. > > > > > > > > Furthermore as this is a "string" attribute you're supposed to also have a > > > > "max_length" and "min_length". > > > > > > Agreed that more examples are better. > > > > > > But are these attributes really mandatory? > > > "This attribute is mandatory" is only specified for "type" and> > > "current_value". > > > > Ah wow, I had thought they were, but you're right they're not! > > > > > While "possible_values" certainly looks necessary for "enumeration", > > > "min_length" for "strings" does so much less. > > > > Even if they're not mandatory, I think it's better to include them for the > > same copy/paste reason I mentioned though. > > Thinking about it some more, which attributes should all be included? > Having all of them in there could motivate driver authors to implement > them all even it would mean filling in random values. > The provided examples can already be copied-and-pasted and slightly > adapted to add more attributes. Hi, Can't you like add comments to the optional ones to reduce the incentive to fill them with random junk as it's a lot easier to just delete them than generating some random junk. So if a developer is unsure what to do a comment telling something is optional would help to lean towards 'I can safely delete this'? -- i. > Also as for providing an even higher level interface. There exists a > fairly big feature matrix. For example the display_name_language_code: > * Is it used at all? > * Is it the same for all attributes implemented by the driver and the > sysfs attribute can be reused for them all. > * Should the same handler logic be reused between different settings which > only differ in their language code? > > The answers seem to differ between each driver and having a uniform > high-level interface that can handle all cases would look horrible. > So I'd like to stick with the API provided currently for now and we can > revisit it if there are more drivers. > As mentioned before, the current API should be a decent baseline to > build on top of. > > > Thomas >
