Re: [PATCH v3 3/3] platform/x86: intel_pmc_core: Instantiate pmc_core device on legacy platforms

[Rajat Jain]

On Mon, Apr 8, 2019 at 10:07 AM Andy Shevchenko
<andy.shevchenko@xxxxxxxxx> wrote:
>
> On Fri, Apr 5, 2019 at 11:36 PM Rajat Jain <rajatja@xxxxxxxxxx> wrote:
> >
> > Add code to instantiate the pmc_core platform device and thus attach to
> > the driver, if the ACPI device for the same ("INT33A1") is not present
> > in a system where it should be. This was discussed here:
> > https://www.mail-archive.com/linux-kernel@xxxxxxxxxxxxxxx/msg1966991.html
> >
>
>
>
> > +#include <linux/acpi.h>
> > +#include <linux/platform_device.h>
> > +
> > +#include <asm/cpu_device_id.h>
> > +#include <asm/intel-family.h>
> > +
> > +static struct platform_device pmc_core_device = {
> > +       .name = "pmc_core",
> > +};
> > +
>
> > +static int dummy;
> > +/*
> > + * INTEL_CPU_FAM6 macro won't take NULL for driver_data (uses &driver_data),
> > + * thus provide a dummy driver_data.
> > + */
>
> You may use pmc_core_device instead, right?

sure, will do.

>
> > +static const struct x86_cpu_id intel_pmc_core_ids[] = {
> > +       INTEL_CPU_FAM6(SKYLAKE_MOBILE, dummy),
> > +       INTEL_CPU_FAM6(SKYLAKE_DESKTOP, dummy),
> > +       INTEL_CPU_FAM6(KABYLAKE_MOBILE, dummy),
> > +       INTEL_CPU_FAM6(KABYLAKE_DESKTOP, dummy),
> > +       INTEL_CPU_FAM6(CANNONLAKE_MOBILE, dummy),
> > +       INTEL_CPU_FAM6(ICELAKE_MOBILE, dummy),
> > +       {}
> > +};
> > +MODULE_DEVICE_TABLE(x86cpu, intel_pmc_core_ids);
> > +
> > +static int __init pmc_core_platform_init(void)
> > +{
> > +       int ret;
> > +
> > +       /* Skip creating the platform device if ACPI already has a device */
> > +       if (acpi_dev_present("INT33A1", NULL, -1) ||
> > +           !x86_match_cpu(intel_pmc_core_ids))
> > +               return -ENODEV;
>
> Split it to one conditional per line.

sure, will do.

>
> > +
> > +       ret = platform_device_register(&pmc_core_device);
> > +       if (ret)
> > +               return ret;
> > +
> > +       return 0;
> > +}
> > +
> > +static void __exit pmc_core_platform_exit(void)
> > +{
>
> > +       if (!acpi_dev_present("INT33A1", NULL, -1) &&
> > +           x86_match_cpu(intel_pmc_core_ids))
>
> Redundant check.

will fix.

>
> > +               platform_device_unregister(&pmc_core_device);
> > +}
>
> --
> With Best Regards,
> Andy Shevchenko