Re: [PATCH v2] gpiolib: make struct comments into real kernel docs

From: Randy Dunlap
Date: Tue Feb 08 2022 - 11:46:01 EST


Hi--

On 2/8/22 02:48, Bartosz Golaszewski wrote:
> We have several comments that start with '/**' but don't conform to the
> kernel doc standard. Add proper detailed descriptions for the affected
> definitions and move the docs from the forward declarations to the
> struct definitions where applicable.
>
> Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> Signed-off-by: Bartosz Golaszewski <brgl@xxxxxxxx>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

Tested-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>

> ---
> v1 -> v2:
> - described fields not yet documented
> - added missing '@'
> - made using periods consistent
> - fixed struct references
>
> drivers/gpio/gpiolib.h | 34 ++++++++++++++++++++++++++++++++++
> include/linux/gpio/consumer.h | 35 ++++++++++++++++-------------------
> 2 files changed, 50 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h
> index 30bc3f80f83e..40723a179902 100644
> --- a/drivers/gpio/gpiolib.h
> +++ b/drivers/gpio/gpiolib.h
> @@ -37,6 +37,9 @@
> * or name of the IP component in a System on Chip.
> * @data: per-instance data assigned by the driver
> * @list: links gpio_device:s together for traversal
> + * @notifier: used to notify subscribers about lines being requested, released
> + * or reconfigured
> + * @pin_ranges: range of pins served by the GPIO driver
> *
> * This state container holds most of the runtime variable data
> * for a GPIO device and can hold references and live on after the
> @@ -72,6 +75,20 @@ struct gpio_device {
> /* gpio suffixes used for ACPI and device tree lookup */
> static __maybe_unused const char * const gpio_suffixes[] = { "gpios", "gpio" };
>
> +/**
> + * struct gpio_array - Opaque descriptor for a structure of GPIO array attributes
> + *
> + * @desc: Array of pointers to the GPIO descriptors
> + * @size: Number of elements in desc
> + * @chip: Parent GPIO chip
> + * @get_mask: Get mask used in fastpath
> + * @set_mask: Set mask used in fastpath
> + * @invert_mask: Invert mask used in fastpath
> + *
> + * This structure is attached to struct gpiod_descs obtained from

maybe
&struct gpiod_descs

> + * gpiod_get_array() and can be passed back to get/set array functions in order
> + * to activate fast processing path if applicable.
> + */
> struct gpio_array {
> struct gpio_desc **desc;
> unsigned int size;
> @@ -96,6 +113,23 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep,
> extern spinlock_t gpio_lock;
> extern struct list_head gpio_devices;
>
> +
> +/**
> + * struct gpio_desc - Opaque descriptor for a GPIO
> + *
> + * @gdev: Pointer to the parent GPIO device
> + * @flags: Binary descriptor flags
> + * @label: Name of the consumer
> + * @name: Line name
> + * @hog: Pointer to the device node that hogs this line (if any)
> + * @debounce_period_us: Debounce period in microseconds
> + *
> + * These are obtained using gpiod_get() and are preferable to the old
> + * integer-based handles.
> + *
> + * Contrary to integers, a pointer to a &struct gpio_desc is guaranteed to be
> + * valid until the GPIO is released.
> + */
> struct gpio_desc {
> struct gpio_device *gdev;
> unsigned long flags;
> diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
> index 3ad67b4a72be..c3aa8b330e1c 100644
> --- a/include/linux/gpio/consumer.h
> +++ b/include/linux/gpio/consumer.h
> @@ -8,27 +8,16 @@
> #include <linux/err.h>
>
> struct device;
> -
> -/**
> - * Opaque descriptor for a GPIO. These are obtained using gpiod_get() and are
> - * preferable to the old integer-based handles.
> - *
> - * Contrary to integers, a pointer to a gpio_desc is guaranteed to be valid
> - * until the GPIO is released.
> - */
> struct gpio_desc;
> -
> -/**
> - * Opaque descriptor for a structure of GPIO array attributes. This structure
> - * is attached to struct gpiod_descs obtained from gpiod_get_array() and can be
> - * passed back to get/set array functions in order to activate fast processing
> - * path if applicable.
> - */
> struct gpio_array;
>
> /**
> - * Struct containing an array of descriptors that can be obtained using
> - * gpiod_get_array().
> + * struct gpio_descs - Struct containing an array of descriptors that can be
> + * obtained using gpiod_get_array()
> + *
> + * @info: Pointer to the opaque gpio_array structure
> + * @ndescs: Number of held descriptors
> + * @desc: Array of pointers to GPIO descriptors
> */
> struct gpio_descs {
> struct gpio_array *info;
> @@ -43,8 +32,16 @@ struct gpio_descs {
> #define GPIOD_FLAGS_BIT_NONEXCLUSIVE BIT(4)
>
> /**
> - * Optional flags that can be passed to one of gpiod_* to configure direction
> - * and output value. These values cannot be OR'd.
> + * enum gpiod_flags - Optional flags that can be passed to one of gpiod_* to
> + * configure direction and output value. These values
> + * cannot be OR'd.
> + *
> + * @GPIOD_ASIS: Don't change anything
> + * @GPIOD_IN: Set lines to input mode
> + * @GPIOD_OUT_LOW: Set lines to output and drive them low
> + * @GPIOD_OUT_HIGH: Set lines to output and drive them high
> + * @GPIOD_OUT_LOW_OPEN_DRAIN: Set lines to open-drain output and drive them low
> + * @GPIOD_OUT_HIGH_OPEN_DRAIN: Set lines to open-drain output and drive them high
> */
> enum gpiod_flags {
> GPIOD_ASIS = 0,


thanks.
--
~Randy