| Message ID | 20191127084253.16356-4-geert+renesas@glider.be (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | gpio: Add GPIO Aggregator/Repeater | expand |
> On November 27, 2019 at 9:42 AM Geert Uytterhoeven <geert+renesas@glider.be> wrote: > > > Currently GPIOs can only be referred to by GPIO controller and offset in > GPIO lookup tables. > > Add support for looking them up by line name. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> > --- > If this is rejected, the GPIO Aggregator documentation and code must be > updated. > > v3: > - New. > --- > drivers/gpio/gpiolib.c | 12 ++++++++++++ > include/linux/gpio/machine.h | 2 +- > 2 files changed, 13 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c > index d24a3d79dcfe69ad..cb608512ad6bbded 100644 > --- a/drivers/gpio/gpiolib.c > +++ b/drivers/gpio/gpiolib.c > @@ -4475,6 +4475,18 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, > if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) > continue; > > + if (p->chip_hwnum == (u16)-1) { > + desc = gpio_name_to_desc(p->chip_label); > + if (desc) { > + *flags = p->flags; > + return desc; > + } > + > + dev_warn(dev, "cannot find GPIO line %s, deferring\n", > + p->chip_label); > + return ERR_PTR(-EPROBE_DEFER); > + } > + > chip = find_chip_by_name(p->chip_label); > > if (!chip) { > diff --git a/include/linux/gpio/machine.h b/include/linux/gpio/machine.h > index 1ebe5be05d5f81fa..84c1c097e55eefaf 100644 > --- a/include/linux/gpio/machine.h > +++ b/include/linux/gpio/machine.h > @@ -31,7 +31,7 @@ enum gpio_lookup_flags { > */ > struct gpiod_lookup { > const char *chip_label; > - u16 chip_hwnum; > + u16 chip_hwnum; /* if -1, chip_label is named line */ The magic number "-1" might deserve a #define. > const char *con_id; > unsigned int idx; > unsigned long flags; > -- > 2.17.1 > With or without #define, Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> CU Uli
On Wed, Nov 27, 2019 at 9:43 AM Geert Uytterhoeven <geert+renesas@glider.be> wrote: > Currently GPIOs can only be referred to by GPIO controller and offset in > GPIO lookup tables. > > Add support for looking them up by line name. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> OK I see what you want to do... > + if (p->chip_hwnum == (u16)-1) { If you want to use this then use: if (p->chip_hwnum == U16_MAX) from <linux/limits.h> > + desc = gpio_name_to_desc(p->chip_label); > + if (desc) { > + *flags = p->flags; > + return desc; > + } > + > + dev_warn(dev, "cannot find GPIO line %s, deferring\n", > + p->chip_label); > + return ERR_PTR(-EPROBE_DEFER); > + } > + > chip = find_chip_by_name(p->chip_label); > > if (!chip) { > diff --git a/include/linux/gpio/machine.h b/include/linux/gpio/machine.h > index 1ebe5be05d5f81fa..84c1c097e55eefaf 100644 > --- a/include/linux/gpio/machine.h > +++ b/include/linux/gpio/machine.h > @@ -31,7 +31,7 @@ enum gpio_lookup_flags { > */ > struct gpiod_lookup { > const char *chip_label; > - u16 chip_hwnum; > + u16 chip_hwnum; /* if -1, chip_label is named line */ /* if U16_MAX then chip_label is the named line we are looking for */ But the member name "chip_label" is completely abused with this setup, it should then be renamed as part of the patch set to something like chip_label_or_line_name so it is clear what it is or just name it "const char *key". But I'm not entirely convinced about reusing the existing struct gpio_lookup for this. What about constructing a new lookup struct specifically for this? I understand it is more work, but will that not be more maintainable and readable? Yours, Linus Walleij
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index d24a3d79dcfe69ad..cb608512ad6bbded 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -4475,6 +4475,18 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) continue; + if (p->chip_hwnum == (u16)-1) { + desc = gpio_name_to_desc(p->chip_label); + if (desc) { + *flags = p->flags; + return desc; + } + + dev_warn(dev, "cannot find GPIO line %s, deferring\n", + p->chip_label); + return ERR_PTR(-EPROBE_DEFER); + } + chip = find_chip_by_name(p->chip_label); if (!chip) { diff --git a/include/linux/gpio/machine.h b/include/linux/gpio/machine.h index 1ebe5be05d5f81fa..84c1c097e55eefaf 100644 --- a/include/linux/gpio/machine.h +++ b/include/linux/gpio/machine.h @@ -31,7 +31,7 @@ enum gpio_lookup_flags { */ struct gpiod_lookup { const char *chip_label; - u16 chip_hwnum; + u16 chip_hwnum; /* if -1, chip_label is named line */ const char *con_id; unsigned int idx; unsigned long flags;
Currently GPIOs can only be referred to by GPIO controller and offset in GPIO lookup tables. Add support for looking them up by line name. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> --- If this is rejected, the GPIO Aggregator documentation and code must be updated. v3: - New. --- drivers/gpio/gpiolib.c | 12 ++++++++++++ include/linux/gpio/machine.h | 2 +- 2 files changed, 13 insertions(+), 1 deletion(-)