diff options
| author | Ioana Ciornei <ioana.ciornei@nxp.com> | 2025-10-14 18:53:53 +0300 |
|---|---|---|
| committer | Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2025-10-22 08:52:17 +0200 |
| commit | 00aaae60faf554c27c95e93d47f200a93ff266ef (patch) | |
| tree | 982d7fc3dd747b844accbae21e59eff576d541dd | |
| parent | d37623132a6347b4ab9e2179eb3f2fa77863c364 (diff) | |
| download | net-00aaae60faf554c27c95e93d47f200a93ff266ef.tar.gz | |
gpio: regmap: add the .fixed_direction_output configuration parameter
There are GPIO controllers such as the one present in the LX2160ARDB
QIXIS FPGA which have fixed-direction input and output GPIO lines mixed
together in a single register. This cannot be modeled using the
gpio-regmap as-is since there is no way to present the true direction of
a GPIO line.
In order to make this use case possible, add a new configuration
parameter - fixed_direction_output - into the gpio_regmap_config
structure. This will enable user drivers to provide a bitmap that
represents the fixed direction of the GPIO lines.
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Michael Walle <mwalle@kernel.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
| -rw-r--r-- | drivers/gpio/gpio-regmap.c | 26 | ||||
| -rw-r--r-- | include/linux/gpio/regmap.h | 5 |
2 files changed, 29 insertions, 2 deletions
diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c index ab9e4077fa608c..f4267af00027e2 100644 --- a/drivers/gpio/gpio-regmap.c +++ b/drivers/gpio/gpio-regmap.c @@ -31,6 +31,7 @@ struct gpio_regmap { unsigned int reg_clr_base; unsigned int reg_dir_in_base; unsigned int reg_dir_out_base; + unsigned long *fixed_direction_output; #ifdef CONFIG_REGMAP_IRQ int regmap_irq_line; @@ -134,6 +135,13 @@ static int gpio_regmap_get_direction(struct gpio_chip *chip, unsigned int base, val, reg, mask; int invert, ret; + if (gpio->fixed_direction_output) { + if (test_bit(offset, gpio->fixed_direction_output)) + return GPIO_LINE_DIRECTION_OUT; + else + return GPIO_LINE_DIRECTION_IN; + } + if (gpio->reg_dat_base && !gpio->reg_set_base) return GPIO_LINE_DIRECTION_IN; if (gpio->reg_set_base && !gpio->reg_dat_base) @@ -284,6 +292,17 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config goto err_free_gpio; } + if (config->fixed_direction_output) { + gpio->fixed_direction_output = bitmap_alloc(chip->ngpio, + GFP_KERNEL); + if (!gpio->fixed_direction_output) { + ret = -ENOMEM; + goto err_free_gpio; + } + bitmap_copy(gpio->fixed_direction_output, + config->fixed_direction_output, chip->ngpio); + } + /* if not set, assume there is only one register */ gpio->ngpio_per_reg = config->ngpio_per_reg; if (!gpio->ngpio_per_reg) @@ -300,7 +319,7 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config ret = gpiochip_add_data(chip, gpio); if (ret < 0) - goto err_free_gpio; + goto err_free_bitmap; #ifdef CONFIG_REGMAP_IRQ if (config->regmap_irq_chip) { @@ -309,7 +328,7 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config config->regmap_irq_line, config->regmap_irq_flags, 0, config->regmap_irq_chip, &gpio->irq_chip_data); if (ret) - goto err_free_gpio; + goto err_free_bitmap; irq_domain = regmap_irq_get_domain(gpio->irq_chip_data); } else @@ -326,6 +345,8 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config err_remove_gpiochip: gpiochip_remove(chip); +err_free_bitmap: + bitmap_free(gpio->fixed_direction_output); err_free_gpio: kfree(gpio); return ERR_PTR(ret); @@ -344,6 +365,7 @@ void gpio_regmap_unregister(struct gpio_regmap *gpio) #endif gpiochip_remove(&gpio->gpio_chip); + bitmap_free(gpio->fixed_direction_output); kfree(gpio); } EXPORT_SYMBOL_GPL(gpio_regmap_unregister); diff --git a/include/linux/gpio/regmap.h b/include/linux/gpio/regmap.h index 622a2939ebe0fd..87983a5f3681e5 100644 --- a/include/linux/gpio/regmap.h +++ b/include/linux/gpio/regmap.h @@ -38,6 +38,10 @@ struct regmap; * offset to a register/bitmask pair. If not * given the default gpio_regmap_simple_xlate() * is used. + * @fixed_direction_output: + * (Optional) Bitmap representing the fixed direction of + * the GPIO lines. Useful when there are GPIO lines with a + * fixed direction mixed together in the same register. * @drvdata: (Optional) Pointer to driver specific data which is * not used by gpio-remap but is provided "as is" to the * driver callback(s). @@ -85,6 +89,7 @@ struct gpio_regmap_config { int reg_stride; int ngpio_per_reg; struct irq_domain *irq_domain; + unsigned long *fixed_direction_output; #ifdef CONFIG_REGMAP_IRQ struct regmap_irq_chip *regmap_irq_chip; |