Re: [PATCH v2 1/1] platform/x86/intel_cht_int33fe: Split code to USB TypeB and TypeC variants
From: Yauhen Kharuzhy
Date: Wed Sep 18 2019 - 07:52:53 EST
On Wed, Sep 18, 2019 at 02:38:35PM +0300, Heikki Krogerus wrote:
> On Tue, Sep 17, 2019 at 10:45:07PM +0300, Yauhen Kharuzhy wrote:
> > Existing intel_cht_int33fe ACPI pseudo-device driver assumes that
> > hardware has TypeC connector and register related devices described as
> > I2C connections in the _CRS resource.
> >
> > There is at least one hardware (Lenovo Yoga Book YB1-91L/F) with micro
> > USB B connector exists. It has INT33FE device in the DSDT table but
> > there are only two I2C connection described: PMIC and BQ27452 battery
> > fuel gauge.
> >
> > Splitting existing INT33FE driver allow to maintain code for USB type B
> > (AB) connector variant separately and make it simpler.
>
> Sorry, but "Type B" is even more confusing here. Type B refers to the
> Standard-B USB connector, so _not_ the micro connector family. You can
> check the connector definitions from the latest USB 3.2 specification.
> The standard-b definition goes something like this:
>
> "The standard _Type-B_ connector defined by the USB x specification."
>
> Note that all the five supported connectors are listed in ch5
> "Mechanical":
>
> Standard-A
> Standard-B
> Micro-B
> Micro-AB
> Type-C
>
> So what was the problem with names that refer to the micro connector
> family, for example "micro-ab" or "micro-b"?
Only one problem: there is no difference between micro B, micro AB, mini
B or Standard-B types of connectors from this driver point of view â all
of them can be used for device charging. Now we have only two kind of
hardware with INT33FE pseudo-device: with Micro-B and Type-C connectors
but other kind may exist. TypeB is not standartized but it seemed to me
a good generalization of "USB connectors to charger connection but not
Type-C". No problem to change it to other suitable name, 'simple', 'dumb',
'non-TypeC' or 'micro-B'. All this names are not ideal.
--
Yauhen Kharuzhy