Re: [PATCH v2 4/4] pinctrl: s32cc: embed generic struct pingroup and pinfunction

[Chester Lin <clin@suse.com>]

On Mon, Mar 20, 2023 at 07:10:40PM +0200, Andy Shevchenko wrote:
> On Mon, Mar 20, 2023 at 6:39 PM Chester Lin <clin@suse.com> wrote:
> >
> > Use generic data structure to describe pin control functions and groups in
> > S32 SoC family and drop duplicated struct members.
> 
> Not sure about the need of the casting, see below, otherwise LGTM.
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 
> > Signed-off-by: Chester Lin <clin@suse.com>
> > ---
> > Changes in v2:
> > - Simply use generic 'struct pinfunction' rather than having extra 'struct
> >   s32_pmx_func'.
> >
> >  drivers/pinctrl/nxp/pinctrl-s32.h   | 26 ++--------
> >  drivers/pinctrl/nxp/pinctrl-s32cc.c | 76 +++++++++++++++--------------
> >  2 files changed, 45 insertions(+), 57 deletions(-)
> >
> > diff --git a/drivers/pinctrl/nxp/pinctrl-s32.h b/drivers/pinctrl/nxp/pinctrl-s32.h
> > index 545bf16b988d..2f7aecd462e4 100644
> > --- a/drivers/pinctrl/nxp/pinctrl-s32.h
> > +++ b/drivers/pinctrl/nxp/pinctrl-s32.h
> > @@ -15,31 +15,15 @@ struct platform_device;
> >
> >  /**
> >   * struct s32_pin_group - describes an S32 pin group
> > - * @name: the name of this specific pin group
> > - * @npins: the number of pins in this group array, i.e. the number of
> > - *         elements in pin_ids and pin_sss so we can iterate over that array
> > - * @pin_ids: an array of pin IDs in this group
> > - * @pin_sss: an array of source signal select configs paired with pin_ids
> > + * @data: generic data describes group name, number of pins, and a pin array in
> > +       this group.
> > + * @pin_sss: an array of source signal select configs paired with pin array.
> >   */
> >  struct s32_pin_group {
> > -       const char *name;
> > -       unsigned int npins;
> > -       unsigned int *pin_ids;
> > +       struct pingroup data;
> >         unsigned int *pin_sss;
> >  };
> >
> > -/**
> > - * struct s32_pmx_func - describes S32 pinmux functions
> > - * @name: the name of this specific function
> > - * @groups: corresponding pin groups
> > - * @num_groups: the number of groups
> > - */
> > -struct s32_pmx_func {
> > -       const char *name;
> > -       const char **groups;
> > -       unsigned int num_groups;
> > -};
> > -
> >  /**
> >   * struct s32_pin_range - pin ID range for each memory region.
> >   * @start: start pin ID
> > @@ -56,7 +40,7 @@ struct s32_pinctrl_soc_info {
> >         unsigned int npins;
> >         struct s32_pin_group *groups;
> >         unsigned int ngroups;
> > -       struct s32_pmx_func *functions;
> > +       struct pinfunction *functions;
> >         unsigned int nfunctions;
> >         unsigned int grp_index;
> >         const struct s32_pin_range *mem_pin_ranges;
> > diff --git a/drivers/pinctrl/nxp/pinctrl-s32cc.c b/drivers/pinctrl/nxp/pinctrl-s32cc.c
> > index cb8a0844c0fa..4ed0cc905232 100644
> > --- a/drivers/pinctrl/nxp/pinctrl-s32cc.c
> > +++ b/drivers/pinctrl/nxp/pinctrl-s32cc.c
> > @@ -188,7 +188,7 @@ static const char *s32_get_group_name(struct pinctrl_dev *pctldev,
> >         struct s32_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
> >         const struct s32_pinctrl_soc_info *info = ipctl->info;
> >
> > -       return info->groups[selector].name;
> > +       return info->groups[selector].data.name;
> >  }
> >
> >  static int s32_get_group_pins(struct pinctrl_dev *pctldev,
> > @@ -198,8 +198,8 @@ static int s32_get_group_pins(struct pinctrl_dev *pctldev,
> >         struct s32_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
> >         const struct s32_pinctrl_soc_info *info = ipctl->info;
> >
> > -       *pins = info->groups[selector].pin_ids;
> > -       *npins = info->groups[selector].npins;
> > +       *pins = info->groups[selector].data.pins;
> > +       *npins = info->groups[selector].data.npins;
> >
> >         return 0;
> >  }
> > @@ -314,23 +314,23 @@ static int s32_pmx_set(struct pinctrl_dev *pctldev, unsigned int selector,
> >         grp = &info->groups[group];
> >
> >         dev_dbg(ipctl->dev, "set mux for function %s group %s\n",
> > -               info->functions[selector].name, grp->name);
> > +               info->functions[selector].name, grp->data.name);
> >
> >         /* Check beforehand so we don't have a partial config. */
> > -       for (i = 0; i < grp->npins; i++) {
> > -               if (s32_check_pin(pctldev, grp->pin_ids[i]) != 0) {
> > +       for (i = 0; i < grp->data.npins; i++) {
> > +               if (s32_check_pin(pctldev, grp->data.pins[i]) != 0) {
> >                         dev_err(info->dev, "invalid pin: %u in group: %u\n",
> > -                               grp->pin_ids[i], group);
> > +                               grp->data.pins[i], group);
> >                         return -EINVAL;
> >                 }
> >         }
> >
> > -       for (i = 0, ret = 0; i < grp->npins && !ret; i++) {
> > -               ret = s32_regmap_update(pctldev, grp->pin_ids[i],
> > +       for (i = 0, ret = 0; i < grp->data.npins && !ret; i++) {
> > +               ret = s32_regmap_update(pctldev, grp->data.pins[i],
> >                                         S32_MSCR_SSS_MASK, grp->pin_sss[i]);
> >                 if (ret) {
> >                         dev_err(info->dev, "Failed to set pin %u\n",
> > -                               grp->pin_ids[i]);
> > +                               grp->data.pins[i]);
> >                         return ret;
> >                 }
> >         }
> > @@ -364,7 +364,7 @@ static int s32_pmx_get_groups(struct pinctrl_dev *pctldev,
> >         const struct s32_pinctrl_soc_info *info = ipctl->info;
> >
> >         *groups = info->functions[selector].groups;
> > -       *num_groups = info->functions[selector].num_groups;
> > +       *num_groups = info->functions[selector].ngroups;
> >
> >         return 0;
> >  }
> > @@ -602,8 +602,8 @@ static int s32_pconf_group_set(struct pinctrl_dev *pctldev, unsigned int selecto
> >         int i, ret;
> >
> >         grp = &info->groups[selector];
> > -       for (i = 0; i < grp->npins; i++) {
> > -               ret = s32_pinconf_mscr_update(pctldev, grp->pin_ids[i],
> > +       for (i = 0; i < grp->data.npins; i++) {
> > +               ret = s32_pinconf_mscr_update(pctldev, grp->data.pins[i],
> >                                               configs, num_configs);
> >                 if (ret)
> >                         return ret;
> > @@ -637,9 +637,9 @@ static void s32_pinconf_group_dbg_show(struct pinctrl_dev *pctldev,
> >
> >         seq_puts(s, "\n");
> >         grp = &info->groups[selector];
> > -       for (i = 0; i < grp->npins; i++) {
> > -               name = pin_get_name(pctldev, grp->pin_ids[i]);
> > -               ret = s32_regmap_read(pctldev, grp->pin_ids[i], &config);
> > +       for (i = 0; i < grp->data.npins; i++) {
> > +               name = pin_get_name(pctldev, grp->data.pins[i]);
> > +               ret = s32_regmap_read(pctldev, grp->data.pins[i], &config);
> >                 if (ret)
> >                         return;
> >                 seq_printf(s, "%s: 0x%x\n", name, config);
> > @@ -732,6 +732,7 @@ static int s32_pinctrl_parse_groups(struct device_node *np,
> >         const __be32 *p;
> >         struct device *dev;
> >         struct property *prop;
> > +       unsigned int *pins, *sss;
> >         int i, npins;
> >         u32 pinmux;
> >
> > @@ -740,38 +741,38 @@ static int s32_pinctrl_parse_groups(struct device_node *np,
> >         dev_dbg(dev, "group: %pOFn\n", np);
> >
> >         /* Initialise group */
> > -       grp->name = np->name;
> > +       grp->data.name = np->name;
> >
> >         npins = of_property_count_elems_of_size(np, "pinmux", sizeof(u32));
> >         if (npins < 0) {
> >                 dev_err(dev, "Failed to read 'pinmux' property in node %s.\n",
> > -                       grp->name);
> > +                       grp->data.name);
> >                 return -EINVAL;
> >         }
> >         if (!npins) {
> > -               dev_err(dev, "The group %s has no pins.\n", grp->name);
> > +               dev_err(dev, "The group %s has no pins.\n", grp->data.name);
> >                 return -EINVAL;
> >         }
> >
> > -       grp->npins = npins;
> > +       grp->data.npins = npins;
> >
> > -       grp->pin_ids = devm_kcalloc(info->dev, grp->npins,
> > -                                   sizeof(unsigned int), GFP_KERNEL);
> > -       grp->pin_sss = devm_kcalloc(info->dev, grp->npins,
> > -                                   sizeof(unsigned int), GFP_KERNEL);
> > -       if (!grp->pin_ids || !grp->pin_sss)
> > +       pins = devm_kcalloc(info->dev, npins, sizeof(*pins), GFP_KERNEL);
> > +       sss = devm_kcalloc(info->dev, npins, sizeof(*sss), GFP_KERNEL);
> > +       if (!pins || !sss)
> >                 return -ENOMEM;
> >
> >         i = 0;
> >         of_property_for_each_u32(np, "pinmux", prop, p, pinmux) {
> > -               grp->pin_ids[i] = get_pin_no(pinmux);
> > -               grp->pin_sss[i] = get_pin_func(pinmux);
> > +               pins[i] = get_pin_no(pinmux);
> > +               sss[i] = get_pin_func(pinmux);
> >
> > -               dev_dbg(info->dev, "pin-id: 0x%x, sss: 0x%x",
> > -                       grp->pin_ids[i], grp->pin_sss[i]);
> > +               dev_dbg(info->dev, "pin: 0x%x, sss: 0x%x", pins[i], sss[i]);
> >                 i++;
> >         }
> >
> > +       grp->data.pins = pins;
> > +       grp->pin_sss = sss;
> > +
> >         return 0;
> >  }
> >
> > @@ -780,8 +781,9 @@ static int s32_pinctrl_parse_functions(struct device_node *np,
> >                                         u32 index)
> >  {
> >         struct device_node *child;
> > -       struct s32_pmx_func *func;
> > +       struct pinfunction *func;
> >         struct s32_pin_group *grp;
> > +       char **groups;
> >         u32 i = 0;
> >         int ret = 0;
> >
> > @@ -791,18 +793,18 @@ static int s32_pinctrl_parse_functions(struct device_node *np,
> >
> >         /* Initialise function */
> >         func->name = np->name;
> > -       func->num_groups = of_get_child_count(np);
> > -       if (func->num_groups == 0) {
> > +       func->ngroups = of_get_child_count(np);
> > +       if (func->ngroups == 0) {
> >                 dev_err(info->dev, "no groups defined in %pOF\n", np);
> >                 return -EINVAL;
> >         }
> > -       func->groups = devm_kcalloc(info->dev, func->num_groups,
> > -                                   sizeof(*func->groups), GFP_KERNEL);
> > -       if (!func->groups)
> > +       groups = devm_kcalloc(info->dev, func->ngroups,
> > +                             sizeof(*func->groups), GFP_KERNEL);
> > +       if (!groups)
> >                 return -ENOMEM;
> >
> >         for_each_child_of_node(np, child) {
> > -               func->groups[i] = child->name;
> > +               groups[i] = (char *)child->name;
> >                 grp = &info->groups[info->grp_index++];
> >                 ret = s32_pinctrl_parse_groups(child, grp, info);
> >                 if (ret)
> > @@ -810,6 +812,8 @@ static int s32_pinctrl_parse_functions(struct device_node *np,
> >                 i++;
> >         }
> >
> > +       func->groups = (const char **)groups;
> 
> Hmm... Why is casting needed?

It's used for fulfilling the type checking done by kbuild otherwise an error will occur:

drivers/pinctrl/nxp/pinctrl-s32cc.c:815:22: error: assignment to 'const char * const*' from incompatible pointer type 'char **' [-Werror=incompatible-pointer-types]

In 'struct pinfunction', the member 'groups' is declared as (const char * const *).

Regards,
Chester

> 
> >         return 0;
> >  }
> 
> -- 
> With Best Regards,
> Andy Shevchenko