Re: [PATCH 2/2] soc: imx: gpcv2: make pgc driver more generic for other i.MX platforms

[Andrey Smirnov <andrew.smirnov@gmail.com>]

On Tue, Aug 28, 2018 at 12:28 AM Anson Huang <anson.huang@nxp.com> wrote:
>
>
>
> Anson Huang
> Best Regards!
>
>
> > -----Original Message-----
> > From: Andrey Smirnov <andrew.smirnov@gmail.com>
> > Sent: Tuesday, August 28, 2018 6:51 AM
> > To: Anson Huang <anson.huang@nxp.com>
> > Cc: Shawn Guo <shawnguo@kernel.org>; Sascha Hauer
> > <s.hauer@pengutronix.de>; Sascha Hauer <kernel@pengutronix.de>; Fabio
> > Estevam <fabio.estevam@nxp.com>; linux-arm-kernel
> > <linux-arm-kernel@lists.infradead.org>; linux-kernel
> > <linux-kernel@vger.kernel.org>; dl-linux-imx <linux-imx@nxp.com>
> > Subject: Re: [PATCH 2/2] soc: imx: gpcv2: make pgc driver more generic for
> > other i.MX platforms
> >
> > On Sun, Aug 5, 2018 at 11:45 PM Anson Huang <Anson.Huang@nxp.com>
> > wrote:
> > >
> > > i.MX8MQ and i.MX8MM share same gpc module with i.MX7D, they can reuse
> > > gpcv2 pgc driver for power domain control, this patch renames all
> > > functions and structure definitions started with "imx7" to "imx", and
> > > check machine type to pass platform specific power domain data for
> > > power domain driver, thus make
> > > gpcv2 pgc driver more generic for i.MX platforms.
> > >
> >
> > Just for the sake of
> >
> >
> > > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > > ---
> > >  drivers/soc/imx/gpcv2.c | 68
> > > +++++++++++++++++++++++++++++--------------------
> > >  1 file changed, 40 insertions(+), 28 deletions(-)
> > >
> > > diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c index
> > > 0e31465..0e33cb5 100644
> > > --- a/drivers/soc/imx/gpcv2.c
> > > +++ b/drivers/soc/imx/gpcv2.c
> > > @@ -53,7 +53,7 @@
> > >
> > >  #define GPC_PGC_CTRL_PCR               BIT(0)
> > >
> > > -struct imx7_pgc_domain {
> > > +struct imx_pgc_domain {
> > >         struct generic_pm_domain genpd;
> > >         struct regmap *regmap;
> > >         struct regulator *regulator;
> > > @@ -69,11 +69,11 @@ struct imx7_pgc_domain {
> > >         struct device *dev;
> > >  };
> > >
> > > -static int imx7_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain
> > > *genpd,
> > > +static int imx_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain *genpd,
> > >                                       bool on)  {
> > > -       struct imx7_pgc_domain *domain = container_of(genpd,
> > > -                                                     struct
> > imx7_pgc_domain,
> > > +       struct imx_pgc_domain *domain = container_of(genpd,
> > > +                                                     struct
> > > + imx_pgc_domain,
> > >                                                       genpd);
> > >         unsigned int offset = on ?
> > >                 GPC_PU_PGC_SW_PUP_REQ :
> > GPC_PU_PGC_SW_PDN_REQ; @@
> > > -150,17 +150,17 @@ static int imx7_gpc_pu_pgc_sw_pxx_req(struct
> > generic_pm_domain *genpd,
> > >         return ret;
> > >  }
> > >
> > > -static int imx7_gpc_pu_pgc_sw_pup_req(struct generic_pm_domain
> > > *genpd)
> > > +static int imx_gpc_pu_pgc_sw_pup_req(struct generic_pm_domain *genpd)
> > >  {
> > > -       return imx7_gpc_pu_pgc_sw_pxx_req(genpd, true);
> > > +       return imx_gpc_pu_pgc_sw_pxx_req(genpd, true);
> > >  }
> > >
> > > -static int imx7_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain
> > > *genpd)
> > > +static int imx_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain *genpd)
> > >  {
> > > -       return imx7_gpc_pu_pgc_sw_pxx_req(genpd, false);
> > > +       return imx_gpc_pu_pgc_sw_pxx_req(genpd, false);
> > >  }
> > >
> > > -static const struct imx7_pgc_domain imx7_pgc_domains[] = {
> > > +static const struct imx_pgc_domain imx7_pgc_domains[] = {
> > >         [IMX7_POWER_DOMAIN_MIPI_PHY] = {
> > >                 .genpd = {
> > >                         .name      = "mipi-phy",
> > > @@ -198,9 +198,9 @@ static const struct imx7_pgc_domain
> > imx7_pgc_domains[] = {
> > >         },
> > >  };
> > >
> > > -static int imx7_pgc_domain_probe(struct platform_device *pdev)
> > > +static int imx_pgc_domain_probe(struct platform_device *pdev)
> > >  {
> > > -       struct imx7_pgc_domain *domain = pdev->dev.platform_data;
> > > +       struct imx_pgc_domain *domain = pdev->dev.platform_data;
> > >         int ret;
> > >
> > >         domain->dev = &pdev->dev;
> > > @@ -233,9 +233,9 @@ static int imx7_pgc_domain_probe(struct
> > platform_device *pdev)
> > >         return ret;
> > >  }
> > >
> > > -static int imx7_pgc_domain_remove(struct platform_device *pdev)
> > > +static int imx_pgc_domain_remove(struct platform_device *pdev)
> > >  {
> > > -       struct imx7_pgc_domain *domain = pdev->dev.platform_data;
> > > +       struct imx_pgc_domain *domain = pdev->dev.platform_data;
> > >
> > >         of_genpd_del_provider(domain->dev->of_node);
> > >         pm_genpd_remove(&domain->genpd); @@ -243,23 +243,24 @@
> > static
> > > int imx7_pgc_domain_remove(struct platform_device *pdev)
> > >         return 0;
> > >  }
> > >
> > > -static const struct platform_device_id imx7_pgc_domain_id[] = {
> > > -       { "imx7-pgc-domain", },
> > > +static const struct platform_device_id imx_pgc_domain_id[] = {
> > > +       { "imx-pgc-domain", },
> > >         { },
> > >  };
> > >
> > > -static struct platform_driver imx7_pgc_domain_driver = {
> > > +static struct platform_driver imx_pgc_domain_driver = {
> > >         .driver = {
> > > -               .name = "imx7-pgc",
> > > +               .name = "imx-pgc",
> > >         },
> > > -       .probe    = imx7_pgc_domain_probe,
> > > -       .remove   = imx7_pgc_domain_remove,
> > > -       .id_table = imx7_pgc_domain_id,
> > > +       .probe    = imx_pgc_domain_probe,
> > > +       .remove   = imx_pgc_domain_remove,
> > > +       .id_table = imx_pgc_domain_id,
> > >  };
> > > -builtin_platform_driver(imx7_pgc_domain_driver)
> > > +builtin_platform_driver(imx_pgc_domain_driver)
> > >
> > >  static int imx_gpcv2_probe(struct platform_device *pdev)  {
> > > +       static const struct imx_pgc_domain *imx_pgc_domains;
> > >         static const struct regmap_range yes_ranges[] = {
> > >                 regmap_reg_range(GPC_LPCR_A_CORE_BSC,
> > >                                  GPC_M4_PU_PDN_FLG), @@
> > -287,6 +288,7
> > > @@ static int imx_gpcv2_probe(struct platform_device *pdev)
> > >         struct regmap *regmap;
> > >         struct resource *res;
> > >         void __iomem *base;
> > > +       int pgc_max_index;
> > >         int ret;
> > >
> > >         pgc_np = of_get_child_by_name(dev->of_node, "pgc"); @@ -307,9
> > > +309,19 @@ static int imx_gpcv2_probe(struct platform_device *pdev)
> > >                 return ret;
> > >         }
> > >
> > > +       if (of_machine_is_compatible("fsl,imx7d")) {
> > > +               pgc_max_index = ARRAY_SIZE(imx7_pgc_domains);
> > > +               imx_pgc_domains = imx7_pgc_domains;
> > > +       }
> >
> > Is there any reason to do this explicit call to
> > of_machine_is_compatible() as opposed to passing necessary data via .data in
> > imx_gpcv2_dt_ids[]? The latter seems like a more straightforward way of
> > passing variant specific driver info
>
> The reason of NOT using .data is that currently gpcv2 driver uses a structure array
> of imx7_pgc_domains[] which has no fixed length, the .data can ONLY pass the pointer
> of the starting address of imx7_pgc_domains[], and we need to know the array size of
> imx7_pgc_domains, how can we know it if we ONLY got the starting address of this array
> passed from .data. Please advise, thanks.
>

Unless I am missing something, you should be able to do something like:

struct imx_pgc_domain_data {
    struct imx_pgc_domain *domains;
    size_t domains_num;
};

const struct imx_pgc_domain_data imx7_pgc_domain_data = {
    .domains = imx7_pgc_domains,
    .domains_num = ARRAY_SIZE(imx7_pgc_domains),
};

and then just pass imx7_pgc_domain_data via .data. That's a pretty
common idiom in kernel driver.

Thanks,
Andrey Smirnov