Re: [PATCH v8 7/8] platform/chrome: Introduce device tree hardware prober

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Tue, Oct 15, 2024 at 02:32:54PM +0800, Chen-Yu Tsai wrote:
> On Mon, Oct 14, 2024 at 7:23 PM Andy Shevchenko
> <andriy.shevchenko@linux.intel.com> wrote:
> > On Mon, Oct 14, 2024 at 12:56:20PM +0800, Chen-Yu Tsai wrote:
> > > On Thu, Oct 10, 2024 at 11:32 PM Andy Shevchenko
> > > <andriy.shevchenko@linux.intel.com> wrote:
> > > > On Thu, Oct 10, 2024 at 06:29:44PM +0300, Andy Shevchenko wrote:
> > > > > On Tue, Oct 08, 2024 at 03:34:26PM +0800, Chen-Yu Tsai wrote:

...

> > > > > > +   .cfg = &chromeos_i2c_probe_simple_trackpad_cfg,
> > > > >
> > > > >       .cfg = DEFINE_I2C_OF_PROBE_CFG(trackpad, i2c_of_probe_simple_ops),
> > > > >
> > > > > Or even
> > > > >
> > > > > #define DEFINE_I2C_OF_PROBE_CFG_SIMPLE(_type_)                        \
> > > > >       DEFINE_I2C_OF_PROBE_CFG(type, &i2c_of_probe_simple_ops)
> > >
> > > I'm not inclined on using compound literals here. "simple X cfg" will
> > > likely get shared between multiple |chromeos_i2c_probe_data| entries,
> > > and AFAIK the toolchain can't merge them. So we would end up with one
> > > compound literal per entry, even if their contents are the same.
> >
> > I'm not sure I follow, you are using compound literal _already_.
> > How does my proposal change that?
> 
> I'm using it where it makes sense, i.e. where the embedded variable
> is not going to be shared with other instances.
> 
> For the dumb probers, there's only going to be one instance per "type".
> 
> For the simple probers, the config part is still one instance per "type",
> but the parameters are board and component specific. There will be
> multiple instances. Hence the config part can be shared, while the
> parameters likely won't be.
> 
> > > > With that also looking at the above
> > > >
> > > > #define DEFINE_I2C_OF_PROBE_CFG_NONE(_type_)                            \
> > > >         DEFINE_I2C_OF_PROBE_CFG(type, NULL)
> > >
> > > For the "dumb" case it makes sense though, since it would be one instance
> > > per type. But we could go further and just wrap the whole
> > > |chromeos_i2c_probe_data| declaration.
> >
> > Maybe it's too far from now...
> 
> This is what I have:
> 
> #define DEFINE_CHROMEOS_I2C_PROBE_DATA_DUMB(_type)
>                         \
>        static const struct chromeos_i2c_probe_data
> chromeos_i2c_probe_dumb_ ## _type = {       \

>                .cfg = &(const struct i2c_of_probe_cfg) {

But the below is static initializer, why do you need a compound literal here?

>                         \
>                        .type = #_type,
>                         \
>                },
>                         \
> };
> 
> DEFINE_CHROMEOS_I2C_PROBE_DATA_DUMB(touchscreen);

s/dumb/simple/g

-- 
With Best Regards,
Andy Shevchenko