Hi Simon,
maybe you can give me a hint on how to implement this cleanly in driver
model?
To sum it up, I'd like to have a phandle pointing to *any* I2C device,
not knowing which UCLASS actually fits. Then the device and the parent
bus should be probed/prepared such that dm_i2c_read() can be used.
Any ideas on this?
Best regards,
Philip
--
=====================================================================
DENX Software Engineering GmbH, Managing Director: Erika Unter
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-22 Fax: +49-8142-66989-80 Email: p...@denx.de
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On Fri, Oct 13, 2023 at 02:58:04PM +0200, Philip Oberfichtner wrote:
> Hello Heiko,
>
> On Fri, Oct 13, 2023 at 01:28:47PM +0200, Heiko Schocher wrote:
> > [...]
> > >
> > > bootcount {
> > > compatible = "u-boot,bootcount-i2c";
> > > i2c-bus = <&i2c1>;
> > > address = <0x52>;
> >
> > Hmm.. do we really need this here with DTS. Why not using a phandle
> > to a real i2c device? Something like this for example:
> >
> > i2cbcdev = &i2c_rtc;
> >
> > with
> >
> > &i2c1 {
> > i2c_rtc: rtc@68 {
> > [...]
> >
> > and so there is no need for knowing the bus and address ...
> >
>
> Yeah I agree that would be much better, but ...
>
> > [...]
> >
> > when you use a phandle, you can replace the part from reading "offset"
> > with this:
> >
> > uclass_get_device_by_phandle(UCLASS_I2C, dev, "i2cbcdev", &priv->bcdev);
> >
> > of course plus error checking...
>
> This does not work, UCLASS_I2C is used for the *bus above* the device we
> actually want.
>
> Next thing I thougt about: Why not use the UCLASS_I2C_GENERIC. But this
> expects a "i2c-chip" compatible string, which our rtc or whatever device
> obviously does not have.
>
> I think using UCLASS_I2C_GENERIC might indeed be the best approach.
> Maybe using something like 'device_bind_driver()'. But again, this
> expects the parent device to be there already as far as I can tell.
>
> Any suggestions?
>
> Best regards,
> Philip
>
>
> >
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static const struct bootcount_ops bootcount_i2c_ops = {
> > > + .get = bootcount_i2c_get,
> > > + .set = bootcount_i2c_set,
> > > +};
> > > +
> > > +static const struct udevice_id bootcount_i2c_ids[] = {
> > > + { .compatible = "u-boot,bootcount-i2c" },
> > > + { }
> > > +};
> > > +
> > > +U_BOOT_DRIVER(bootcount_i2c) = {
> > > + .name = "bootcount-i2c",
> > > + .id = UCLASS_BOOTCOUNT,
> > > + .priv_auto = sizeof(struct bootcount_i2c_priv),
> > > + .probe = bootcount_i2c_probe,
> > > + .of_match = bootcount_i2c_ids,
> > > + .ops = &bootcount_i2c_ops,
> > > +};
> > >
> >
> > bye,
> > Heiko
> > --
> > DENX Software Engineering GmbH, Managing Director: Erika Unter
> > HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> > Phone: +49-8142-66989-52 Fax: +49-8142-66989-80 Email: h...@denx.de
