diff options
Diffstat (limited to 'drivers/gpio/gpiolib-of.c')
| -rw-r--r-- | drivers/gpio/gpiolib-of.c | 128 |
1 files changed, 121 insertions, 7 deletions
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index 9762dd6d99fa..5c38ede43c7a 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -21,6 +21,34 @@ #include <linux/gpio/machine.h> #include "gpiolib.h" +#include "gpiolib-of.h" + +/* + * This is used by external users of of_gpio_count() from <linux/of_gpio.h> + * + * FIXME: get rid of those external users by converting them to GPIO + * descriptors and let them all use gpiod_get_count() + */ +int of_gpio_get_count(struct device *dev, const char *con_id) +{ + int ret; + char propname[32]; + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { + if (con_id) + snprintf(propname, sizeof(propname), "%s-%s", + con_id, gpio_suffixes[i]); + else + snprintf(propname, sizeof(propname), "%s", + gpio_suffixes[i]); + + ret = of_gpio_named_count(dev->of_node, propname); + if (ret > 0) + break; + } + return ret ? ret : -ENOENT; +} static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data) { @@ -53,6 +81,23 @@ static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip, return gpiochip_get_desc(chip, ret); } +/** + * of_gpio_need_valid_mask() - figure out if the OF GPIO driver needs + * to set the .valid_mask + * @dev: the device for the GPIO provider + * @return: true if the valid mask needs to be set + */ +bool of_gpio_need_valid_mask(const struct gpio_chip *gc) +{ + int size; + struct device_node *np = gc->of_node; + + size = of_property_count_u32_elems(np, "gpio-reserved-ranges"); + if (size > 0 && size % 2 == 0) + return true; + return false; +} + static void of_gpio_flags_quirks(struct device_node *np, const char *propname, enum of_gpio_flags *flags, @@ -231,6 +276,75 @@ int of_get_named_gpio_flags(struct device_node *np, const char *list_name, } EXPORT_SYMBOL(of_get_named_gpio_flags); +/** + * gpiod_get_from_of_node() - obtain a GPIO from an OF node + * @node: handle of the OF node + * @propname: name of the DT property representing the GPIO + * @index: index of the GPIO to obtain for the consumer + * @dflags: GPIO initialization flags + * @label: label to attach to the requested GPIO + * + * Returns: + * On successful request the GPIO pin is configured in accordance with + * provided @dflags. + * + * In case of error an ERR_PTR() is returned. + */ +struct gpio_desc *gpiod_get_from_of_node(struct device_node *node, + const char *propname, int index, + enum gpiod_flags dflags, + const char *label) +{ + unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; + struct gpio_desc *desc; + enum of_gpio_flags flags; + bool active_low = false; + bool single_ended = false; + bool open_drain = false; + bool transitory = false; + int ret; + + desc = of_get_named_gpiod_flags(node, propname, + index, &flags); + + if (!desc || IS_ERR(desc)) { + return desc; + } + + active_low = flags & OF_GPIO_ACTIVE_LOW; + single_ended = flags & OF_GPIO_SINGLE_ENDED; + open_drain = flags & OF_GPIO_OPEN_DRAIN; + transitory = flags & OF_GPIO_TRANSITORY; + + ret = gpiod_request(desc, label); + if (ret == -EBUSY && (flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE)) + return desc; + if (ret) + return ERR_PTR(ret); + + if (active_low) + lflags |= GPIO_ACTIVE_LOW; + + if (single_ended) { + if (open_drain) + lflags |= GPIO_OPEN_DRAIN; + else + lflags |= GPIO_OPEN_SOURCE; + } + + if (transitory) + lflags |= GPIO_TRANSITORY; + + ret = gpiod_configure_flags(desc, propname, lflags, dflags); + if (ret < 0) { + gpiod_put(desc); + return ERR_PTR(ret); + } + + return desc; +} +EXPORT_SYMBOL(gpiod_get_from_of_node); + /* * The SPI GPIO bindings happened before we managed to establish that GPIO * properties should be named "foo-gpios" so we have this special kludge for @@ -734,7 +848,7 @@ static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; } int of_gpiochip_add(struct gpio_chip *chip) { - int status; + int ret; if (!chip->of_node) return 0; @@ -749,9 +863,9 @@ int of_gpiochip_add(struct gpio_chip *chip) of_gpiochip_init_valid_mask(chip); - status = of_gpiochip_add_pin_range(chip); - if (status) - return status; + ret = of_gpiochip_add_pin_range(chip); + if (ret) + return ret; /* If the chip defines names itself, these take precedence */ if (!chip->names) @@ -760,13 +874,13 @@ int of_gpiochip_add(struct gpio_chip *chip) of_node_get(chip->of_node); - status = of_gpiochip_scan_gpios(chip); - if (status) { + ret = of_gpiochip_scan_gpios(chip); + if (ret) { of_node_put(chip->of_node); gpiochip_remove_pin_ranges(chip); } - return status; + return ret; } void of_gpiochip_remove(struct gpio_chip *chip) |