Re: [PATCH 2/2] pinctrl: qcom: sc8180x: add ACPI probe support

[Shawn Guo <shawn.guo@linaro.org>]

On Mon, Mar 01, 2021 at 04:37:50PM +0200, Andy Shevchenko wrote:
> On Mon, Mar 01, 2021 at 09:43:29AM +0800, Shawn Guo wrote:
> > It adds ACPI probe support with tile offsets passed over to msm core
> > driver via sc8180x_tile_offsets, as TLMM is described a single memory
> > region in ACPI DSDT.
> 
> ...
> 
> >  config PINCTRL_SC8180X
> >  	tristate "Qualcomm Technologies Inc SC8180x pin controller driver"
> > -	depends on GPIOLIB && OF
> > +	depends on GPIOLIB && (OF || ACPI)
> 
> Can you consider dropping OF dependency completely?

Not sure.  Looking at those driver options in drivers/pinctrl/qcom/Kconfig,
I think it's a global thing, and should be addressed separately anyway.

> 
> > +#include <linux/acpi.h>
> 
> No use of this header, see below.

has_acpi_companion() and ACPI_PTR use it.

> 
> (Perhaps you meant mod_devicetable.h)
> 
> ...
> 
> > +static const u32 sc8180x_tile_offsets[] = {
> > +	0x00d00000,
> > +	0x00500000,
> > +	0x00100000
> 
> Leave comma here.

Well, this is to respect the taste of original author of the driver, if
you take a look at sc8180x_tiles[] above and enum after.

> 
> > +};
> 
> ...
> 
> > +static const int sc8180x_acpi_reserved_gpios[] = {
> > +	0, 1, 2, 3,
> > +	47, 48, 49, 50,
> > +	126, 127, 128, 129,
> 
> > +	-1
> 
> -1?
> Is it kinda terminator?

Yes, it is.  I will add a comment there.

> 
> > +};
> 
> ...
> 
> > +	if (pdev->dev.of_node) {
> > +		ret = msm_pinctrl_probe(pdev, &sc8180x_pinctrl);
> > +	} else if (has_acpi_companion(&pdev->dev)) {
> > +		ret = msm_pinctrl_probe(pdev, &sc8180x_acpi_pinctrl);
> > +	} else {
> > +		dev_err(&pdev->dev, "DT and ACPI disabled\n");
> > +		ret = -EINVAL;
> > +	}
> 
> Use driver_data field for this and device_get_match_data() instead of above.

Good suggestion, thanks!

> 
> ...
> 
> > +#ifdef CONFIG_ACPI
> 
> Drop this ugly ifdeffery.
> 
> > +static const struct acpi_device_id sc8180x_pinctrl_acpi_match[] = {
> > +	{ "QCOM040D"},
> 
> > +	{ },
> 
> No comma for terminator line.
> 
> > +};
> > +MODULE_DEVICE_TABLE(acpi, sc8180x_pinctrl_acpi_match);
> > +#endif
> 
> ...
> 
> > +		.acpi_match_table = ACPI_PTR(sc8180x_pinctrl_acpi_match),
> 
> No ACPI_PTR(), please.

Sounds good.

Shawn