Re: [PATCH 14/23] gpio: mockup: use the generic 'gpio-line-names' property

[Bartosz Golaszewski]

On Fri, Sep 4, 2020 at 6:46 PM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
>
> On Fri, Sep 04, 2020 at 05:45:38PM +0200, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
> >
> > GPIO line names are currently created by the driver from the chip label.
> > We'll want to support custom formats for line names (for instance: to
> > name all lines the same) for user-space tests so create them in the
> > module init function and pass them to the driver using the standard
> > 'gpio-line-names' property.
> >
> > Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
> > ---
> >  drivers/gpio/gpio-mockup.c | 70 +++++++++++++++++++++-----------------
> >  1 file changed, 38 insertions(+), 32 deletions(-)
> >
> > diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
> > index ce83f1df1933..96976ba66598 100644
> > --- a/drivers/gpio/gpio-mockup.c
> > +++ b/drivers/gpio/gpio-mockup.c
> > @@ -18,6 +18,7 @@
> >  #include <linux/platform_device.h>
> >  #include <linux/property.h>
> >  #include <linux/slab.h>
> > +#include <linux/string_helpers.h>
> >  #include <linux/uaccess.h>
> >
> >  #include "gpiolib.h"
> > @@ -378,29 +379,6 @@ static void gpio_mockup_debugfs_setup(struct device *dev,
> >       return;
> >  }
> >
> > -static int gpio_mockup_name_lines(struct device *dev,
> > -                               struct gpio_mockup_chip *chip)
> > -{
> > -     struct gpio_chip *gc = &chip->gc;
> > -     char **names;
> > -     int i;
> > -
> > -     names = devm_kcalloc(dev, gc->ngpio, sizeof(char *), GFP_KERNEL);
> > -     if (!names)
> > -             return -ENOMEM;
> > -
> > -     for (i = 0; i < gc->ngpio; i++) {
> > -             names[i] = devm_kasprintf(dev, GFP_KERNEL,
> > -                                       "%s-%d", gc->label, i);
> > -             if (!names[i])
> > -                     return -ENOMEM;
> > -     }
> > -
> > -     gc->names = (const char *const *)names;
> > -
> > -     return 0;
> > -}
> > -
> >  static void gpio_mockup_dispose_mappings(void *data)
> >  {
> >       struct gpio_mockup_chip *chip = data;
> > @@ -468,12 +446,6 @@ static int gpio_mockup_probe(struct platform_device *pdev)
> >       for (i = 0; i < gc->ngpio; i++)
> >               chip->lines[i].dir = GPIO_LINE_DIRECTION_IN;
> >
> > -     if (device_property_read_bool(dev, "named-gpio-lines")) {
> > -             rv = gpio_mockup_name_lines(dev, chip);
> > -             if (rv)
> > -                     return rv;
> > -     }
> > -
> >       chip->irq_sim_domain = devm_irq_domain_create_sim(dev, NULL,
> >                                                         gc->ngpio);
> >       if (IS_ERR(chip->irq_sim_domain))
> > @@ -524,6 +496,27 @@ static void gpio_mockup_unregister_devices(void)
> >       }
> >  }
> >
> > +static __init char **gpio_mockup_make_line_names(const char *label,
> > +                                              unsigned int num_lines)
> > +{
> > +     unsigned int i;
> > +     char **names;
> > +
> > +     names = kcalloc(num_lines + 1, sizeof(char *), GFP_KERNEL);
> > +     if (!names)
> > +             return NULL;
> > +
> > +     for (i = 0; i < num_lines; i++) {
> > +             names[i] = kasprintf(GFP_KERNEL, "%s-%u", label, i);
> > +             if (!names[i]) {
> > +                     kfree_strarray(names, i);
> > +                     return NULL;
> > +             }
> > +     }
> > +
> > +     return names;
> > +}
> > +
> >  static int __init gpio_mockup_init(void)
> >  {
> >       struct property_entry properties[GPIO_MOCKUP_MAX_PROP];
> > @@ -531,6 +524,7 @@ static int __init gpio_mockup_init(void)
> >       struct gpio_mockup_device *mockup_dev;
> >       int i, prop, num_chips, err = 0, base;
> >       struct platform_device_info pdevinfo;
> > +     char **line_names;
> >       u16 ngpio;
> >
> >       if ((gpio_mockup_num_ranges < 2) ||
> > @@ -563,6 +557,7 @@ static int __init gpio_mockup_init(void)
> >               memset(properties, 0, sizeof(properties));
> >               memset(&pdevinfo, 0, sizeof(pdevinfo));
> >               prop = 0;
> > +             line_names = NULL;
> >
> >               snprintf(chip_label, sizeof(chip_label),
> >                        "gpio-mockup-%c", i + 'A');
> > @@ -578,9 +573,18 @@ static int __init gpio_mockup_init(void)
> >                                : gpio_mockup_range_ngpio(i) - base;
> >               properties[prop++] = PROPERTY_ENTRY_U16("nr-gpios", ngpio);
> >
> > -             if (gpio_mockup_named_lines)
> > -                     properties[prop++] = PROPERTY_ENTRY_BOOL(
> > -                                             "named-gpio-lines");
> > +             if (gpio_mockup_named_lines) {
> > +                     line_names = gpio_mockup_make_line_names(chip_label,
> > +                                                              ngpio);
> > +                     if (!line_names) {
> > +                             err = -ENOMEM;
> > +                             goto err_out;
> > +                     }
> > +
> > +                     properties[prop++] = PROPERTY_ENTRY_STRING_ARRAY_LEN(
> > +                                             "gpio-line-names",
> > +                                             line_names, ngpio);
> > +             }
>
> Indentation here looks quite deep. Maybe introduce a helper in between where
> you assign properties?
>

No need for that - this gets flattened later on in the series.

Bart