Messages in this thread | | | From | Linus Walleij <> | Date | Thu, 12 Dec 2019 14:20:45 +0100 | Subject | Re: [PATCH v3 2/7] gpiolib: Add support for gpiochipN-based table lookup |
| |
Hi Geert!
On Wed, Nov 27, 2019 at 9:43 AM Geert Uytterhoeven <geert+renesas@glider.be> wrote:
> Currently GPIO controllers can only be referred to by label in GPIO > lookup tables. > > Add support for looking them up by "gpiochipN" name, with "N" either the > corresponding GPIO device's ID number, or the GPIO controller's first > GPIO number. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
What the commit message is missing is a rationale, why is this needed?
> If this is rejected, the GPIO Aggregator documentation must be updated. > > The second variant is currently used by the legacy sysfs interface only, > so perhaps the chip->base check should be dropped?
Anything improving the sysfs is actively discouraged by me. If it is just about staying compatible it is another thing.
> +static int gpiochip_match_id(struct gpio_chip *chip, void *data) > +{ > + int id = (uintptr_t)data; > + > + return id == chip->base || id == chip->gpiodev->id; > +} > static struct gpio_chip *find_chip_by_name(const char *name) > { > - return gpiochip_find((void *)name, gpiochip_match_name); > + struct gpio_chip *chip; > + int id; > + > + chip = gpiochip_find((void *)name, gpiochip_match_name); > + if (chip) > + return chip; > + > + if (!str_has_prefix(name, GPIOCHIP_NAME)) > + return NULL; > + > + if (kstrtoint(name + strlen(GPIOCHIP_NAME), 10, &id)) > + return NULL; > + > + return gpiochip_find((void *)(uintptr_t)id, gpiochip_match_id);
Isn't it easier to just augment the existing match function to check like this:
static int gpiochip_match_name(struct gpio_chip *chip, void *data) { const char *name = data;
if (!strcmp(chip->label, name)) return 0; return !strcmp(dev_name(&chip->gpiodev->dev), name); }
We should I guess also add some kerneldoc to say we first match on the label and second on dev_name().
Yours, Linus Walleij
| |