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

From: Chen-Yu Tsai
Date: Mon Oct 14 2024 - 00:56:44 EST


On Thu, Oct 10, 2024 at 11:32 PM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> 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:
>
> ...
>
> > > +static const struct chromeos_i2c_probe_data chromeos_i2c_probe_dumb_touchscreen = {
> > > + .cfg = &(const struct i2c_of_probe_cfg) {
> >
> > Perhaps you can introduce something like
> >
> > #define DEFINE_I2C_OF_PROBE_CFG(_type_, _ops_) \
> > (struct ...) { \
> > .ops = _ops_, \
> > .type = #_type_, \
> > }
> >
> > and use it here as
> >
> > .cfg = DEFINE_I2C_OF_PROBE_CFG(touchscreen, NULL),
> >
> > > + .type = "touchscreen"
> >
> > Ditto.
>
> This was for leaving trailing comma.

Ack.

> > > + }
> >
> > Ditto.
> >
> > > +};
> > > +
> > > +static const struct i2c_of_probe_cfg chromeos_i2c_probe_simple_trackpad_cfg = {
> > > + .ops = &i2c_of_probe_simple_ops,
> > > + .type = "trackpad"
> >
> > Leave a comma.

Ack

> > > +};
>
> ...
>
> > > + .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.

> 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.


ChenYu