diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 130 |
1 files changed, 84 insertions, 46 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index cd003b74512f..eb80dac4e26a 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -84,7 +84,12 @@ static inline void desc_set_label(struct gpio_desc *d, const char *label) } /** - * Convert a GPIO number to its descriptor + * gpio_to_desc - Convert a GPIO number to its descriptor + * @gpio: global GPIO number + * + * Returns: + * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO + * with the given number exists in the system. */ struct gpio_desc *gpio_to_desc(unsigned gpio) { @@ -111,7 +116,14 @@ struct gpio_desc *gpio_to_desc(unsigned gpio) EXPORT_SYMBOL_GPL(gpio_to_desc); /** - * Get the GPIO descriptor corresponding to the given hw number for this chip. + * gpiochip_get_desc - get the GPIO descriptor corresponding to the given + * hardware number for this chip + * @chip: GPIO chip + * @hwnum: hardware number of the GPIO for this chip + * + * Returns: + * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists + * in the given chip for the specified hardware number. */ struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum) @@ -125,9 +137,14 @@ struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, } /** - * Convert a GPIO descriptor to the integer namespace. + * desc_to_gpio - convert a GPIO descriptor to the integer namespace + * @desc: GPIO descriptor + * * This should disappear in the future but is needed since we still - * use GPIO numbers for error messages and sysfs nodes + * use GPIO numbers for error messages and sysfs nodes. + * + * Returns: + * The global GPIO number for the GPIO specified by its descriptor. */ int desc_to_gpio(const struct gpio_desc *desc) { @@ -254,7 +271,7 @@ static int gpiodev_add_to_list(struct gpio_device *gdev) return -EBUSY; } -/** +/* * Convert a GPIO name to its descriptor */ static struct gpio_desc *gpio_name_to_desc(const char * const name) @@ -878,7 +895,7 @@ out_free_le: return ret; } -/** +/* * gpio_ioctl() - ioctl handler for the GPIO chardev */ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) @@ -1077,11 +1094,9 @@ static void gpiochip_setup_devs(void) /** * gpiochip_add_data() - register a gpio_chip * @chip: the chip to register, with chip->base initialized - * Context: potentially before irqs will work + * @data: driver-private data associated with this chip * - * Returns a negative errno if the chip can't be registered, such as - * because the chip->base is invalid or already associated with a - * different chip. Otherwise it returns zero as a success code. + * Context: potentially before irqs will work * * When gpiochip_add_data() is called very early during boot, so that GPIOs * can be freely used, the chip->parent device must be registered before @@ -1093,6 +1108,11 @@ static void gpiochip_setup_devs(void) * * If chip->base is negative, this requests dynamic assignment of * a range of valid GPIOs. + * + * Returns: + * A negative errno if the chip can't be registered, such as because the + * chip->base is invalid or already associated with a different chip. + * Otherwise it returns zero as a success code. */ int gpiochip_add_data(struct gpio_chip *chip, void *data) { @@ -1287,6 +1307,10 @@ EXPORT_SYMBOL_GPL(gpiochip_add_data); /** * gpiochip_get_data() - get per-subdriver data for the chip + * @chip: GPIO chip + * + * Returns: + * The per-subdriver data for the chip. */ void *gpiochip_get_data(struct gpio_chip *chip) { @@ -1370,13 +1394,16 @@ static int devm_gpio_chip_match(struct device *dev, void *res, void *data) * devm_gpiochip_add_data() - Resource manager piochip_add_data() * @dev: the device pointer on which irq_chip belongs to. * @chip: the chip to register, with chip->base initialized - * Context: potentially before irqs will work + * @data: driver-private data associated with this chip * - * Returns a negative errno if the chip can't be registered, such as - * because the chip->base is invalid or already associated with a - * different chip. Otherwise it returns zero as a success code. + * Context: potentially before irqs will work * * The gpio chip automatically be released when the device is unbound. + * + * Returns: + * A negative errno if the chip can't be registered, such as because the + * chip->base is invalid or already associated with a different chip. + * Otherwise it returns zero as a success code. */ int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip, void *data) @@ -1422,7 +1449,7 @@ EXPORT_SYMBOL_GPL(devm_gpiochip_remove); /** * gpiochip_find() - iterator for locating a specific gpio_chip * @data: data to pass to match function - * @callback: Callback function to check gpio_chip + * @match: Callback function to check gpio_chip * * Similar to bus_find_device. It returns a reference to a gpio_chip as * determined by a user supplied @match callback. The callback should return @@ -1604,6 +1631,9 @@ static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, { struct gpio_chip *chip = d->host_data; + if (!gpiochip_irqchip_irq_valid(chip, hwirq)) + return -ENXIO; + irq_set_chip_data(irq, chip); /* * This lock class tells lockdep that GPIO irqs are in a different @@ -1670,7 +1700,9 @@ static void gpiochip_irq_relres(struct irq_data *d) static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) { - return irq_find_mapping(chip->irqdomain, offset); + if (!gpiochip_irqchip_irq_valid(chip, offset)) + return -ENXIO; + return irq_create_mapping(chip->irqdomain, offset); } /** @@ -1746,9 +1778,6 @@ int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip, struct lock_class_key *lock_key) { struct device_node *of_node; - bool irq_base_set = false; - unsigned int offset; - unsigned irq_base = 0; if (!gpiochip || !irqchip) return -EINVAL; @@ -1774,7 +1803,7 @@ int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip, * conflicting triggers. Tell the user, and reset to NONE. */ if (WARN(of_node && type != IRQ_TYPE_NONE, - "%s: Ignoring %d default trigger\n", of_node->full_name, type)) + "%pOF: Ignoring %d default trigger\n", of_node, type)) type = IRQ_TYPE_NONE; if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) { acpi_handle_warn(ACPI_HANDLE(gpiochip->parent), @@ -1805,25 +1834,6 @@ int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip, irqchip->irq_release_resources = gpiochip_irq_relres; } - /* - * Prepare the mapping since the irqchip shall be orthogonal to - * any gpiochip calls. If the first_irq was zero, this is - * necessary to allocate descriptors for all IRQs. - */ - for (offset = 0; offset < gpiochip->ngpio; offset++) { - if (!gpiochip_irqchip_irq_valid(gpiochip, offset)) - continue; - irq_base = irq_create_mapping(gpiochip->irqdomain, offset); - if (!irq_base_set) { - /* - * Store the base into the gpiochip to be used when - * unmapping the irqs. - */ - gpiochip->irq_base = irq_base; - irq_base_set = true; - } - } - acpi_gpiochip_request_interrupts(gpiochip); return 0; @@ -1930,11 +1940,14 @@ EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); /** * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping * @chip: the gpiochip to add the range for - * @pinctrl_name: the dev_name() of the pin controller to map to + * @pinctl_name: the dev_name() of the pin controller to map to * @gpio_offset: the start offset in the current gpio_chip number space * @pin_offset: the start offset in the pin controller number space * @npins: the number of pins from the offset of each pin space (GPIO and * pin controller) to accumulate in this range + * + * Returns: + * 0 on success, or a negative error-code on failure. */ int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, unsigned int gpio_offset, unsigned int pin_offset, @@ -2179,7 +2192,8 @@ EXPORT_SYMBOL_GPL(gpiochip_is_requested); /** * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor - * @desc: GPIO descriptor to request + * @chip: GPIO chip + * @hwnum: hardware number of the GPIO for which to request the descriptor * @label: label for the GPIO * * Function allows GPIO chip drivers to request and use their own GPIO @@ -2187,6 +2201,10 @@ EXPORT_SYMBOL_GPL(gpiochip_is_requested); * function will not increase reference count of the GPIO chip module. This * allows the GPIO chip module to be unloaded as needed (we assume that the * GPIO chip driver handles freeing the GPIOs it has requested). + * + * Returns: + * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error + * code on failure. */ struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum, const char *label) @@ -2368,12 +2386,13 @@ int gpiod_direction_output(struct gpio_desc *desc, int value) EXPORT_SYMBOL_GPL(gpiod_direction_output); /** - * gpiod_set_debounce - sets @debounce time for a @gpio - * @gpio: the gpio to set debounce time - * @debounce: debounce time is microseconds + * gpiod_set_debounce - sets @debounce time for a GPIO + * @desc: descriptor of the GPIO for which to set debounce time + * @debounce: debounce time in microseconds * - * returns -ENOTSUPP if the controller does not support setting - * debounce. + * Returns: + * 0 on success, %-ENOTSUPP if the controller doesn't support setting the + * debounce time. */ int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) { @@ -2981,6 +3000,23 @@ void gpiod_set_raw_array_value_cansleep(unsigned int array_size, EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep); /** + * gpiod_add_lookup_tables() - register GPIO device consumers + * @tables: list of tables of consumers to register + * @n: number of tables in the list + */ +void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) +{ + unsigned int i; + + mutex_lock(&gpio_lookup_lock); + + for (i = 0; i < n; i++) + list_add_tail(&tables[i]->list, &gpio_lookup_list); + + mutex_unlock(&gpio_lookup_lock); +} + +/** * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs * @array_size: number of elements in the descriptor / value arrays * @desc_array: array of GPIO descriptors whose values will be assigned @@ -3322,6 +3358,7 @@ EXPORT_SYMBOL_GPL(gpiod_get_index); * @propname: name of the firmware property representing the GPIO * @index: index of the GPIO to obtain in the consumer * @dflags: GPIO initialization flags + * @label: label to attach to the requested GPIO * * This function can be used for drivers that get their configuration * from firmware. @@ -3330,6 +3367,7 @@ EXPORT_SYMBOL_GPL(gpiod_get_index); * underlying firmware interface and then makes sure that the GPIO * descriptor is requested before it is returned to the caller. * + * Returns: * On successful request the GPIO pin is configured in accordance with * provided @dflags. * |