On 02 November 2016 14:29, Lee Jones wrote:

> On Mon, 31 Oct 2016, Steve Twiss wrote:
> > From: Steve Twiss <stwiss.opensou...@diasemi.com>
> > 
> > @@ -475,7 +855,25 @@ static int da9062_i2c_probe(struct i2c_client *i2c,
> >             return -EINVAL;
> >     }
> >
> > -   chip->regmap = devm_regmap_init_i2c(i2c, &da9062_regmap_config);
> > +   switch (chip->chip_type) {
> > +   case(COMPAT_TYPE_DA9061):
> > +           cell = da9061_devs;
> > +           cell_num = ARRAY_SIZE(da9061_devs);
> > +           irq_chip = &da9061_irq_chip;
> > +           config = &da9061_regmap_config;
> > +           break;
> > +   case(COMPAT_TYPE_DA9062):
> > +           cell = da9062_devs;
> > +           cell_num = ARRAY_SIZE(da9062_devs);
> > +           irq_chip = &da9062_irq_chip;
> > +           config = &da9062_regmap_config;
> > +           break;
> > +   default:
> > +           dev_err(chip->dev, "Unrecognised chip type\n");
> > +           return -ENODEV;
> > +   }
> 
> I very much dislike when MFD and OF functionality is mixed.
> 
> In your case you can use da9062_get_device_type() to dynamically
> interrogate the device and register using the correct MFD cells that
> way.

Hi Lee,

It's the device tree that decides what the chip type is. It's not chip
interrogation in this case. The ordering dictates this I think: to access the
hardware ID register, a regmap definition is needed first. But because the
correct I2C register map requires a knowledge of what chip is being used,
it becomes a circular dependency.

To solve this dependency, I define the chip type (DA9061 or DA9062) in the
device tree and assign the correct regmap first before accessing any registers.

> > +   chip->regmap = devm_regmap_init_i2c(i2c, config);
> >     if (IS_ERR(chip->regmap)) {
> >             ret = PTR_ERR(chip->regmap);
> >             dev_err(chip->dev, "Failed to allocate register map: %d\n",
> > @@ -493,7 +891,7 @@ static int da9062_i2c_probe(struct i2c_client *i2c,
> >
> >     ret = regmap_add_irq_chip(chip->regmap, i2c->irq,
> >                     IRQF_TRIGGER_LOW | IRQF_ONESHOT |IRQF_SHARED,
> > -                   -1, &da9062_irq_chip,
> > +                   -1, irq_chip,
> 
> What is -1?

.. it's a request for an irq_base.
http://lxr.free-electrons.com/source/kernel/irq/irqdesc.c#L477

Is there a reason I shouldn't be doing that?
There doesn't seem to be a #define anywhere, and using -1 seems
to be the standard in the kernel at the moment.

Regards,
Steve

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