From: Ioana Ciornei ioana.ciornei@nxp.com
[ Upstream commit 00aaae60faf554c27c95e93d47f200a93ff266ef ]
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 Stable-dep-of: 2ba5772e530f ("gpio: idio-16: Define fixed direction of the GPIO lines") Signed-off-by: William Breathitt Gray wbg@kernel.org --- drivers/gpio/gpio-regmap.c | 26 ++++++++++++++++++++++++-- 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 c789001241fd..fd986afa7db5 100644 --- a/drivers/gpio/gpio-regmap.c +++ b/drivers/gpio/gpio-regmap.c @@ -29,6 +29,7 @@ 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; @@ -122,6 +123,13 @@ 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) @@ -280,9 +288,20 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config chip->direction_output = gpio_regmap_direction_output; }
+ 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); + } + 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) { @@ -291,7 +310,7 @@ 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 @@ -308,6 +327,8 @@ 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); @@ -326,6 +347,7 @@ 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 76f6c73106dc..cf55202aaec2 100644 --- a/include/linux/gpio/regmap.h +++ b/include/linux/gpio/regmap.h @@ -37,6 +37,10 @@ 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). @@ -82,6 +86,7 @@ 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;