diff options
Diffstat (limited to 'include/asm-generic/gpio.h')
| -rw-r--r-- | include/asm-generic/gpio.h | 142 |
1 files changed, 121 insertions, 21 deletions
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h index 82294cbdc5..2cb0500aec 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -128,6 +128,12 @@ struct gpio_desc { #define GPIOD_PULL_UP BIT(7) /* GPIO has pull-up enabled */ #define GPIOD_PULL_DOWN BIT(8) /* GPIO has pull-down enabled */ +/* Flags for updating the above */ +#define GPIOD_MASK_DIR (GPIOD_IS_OUT | GPIOD_IS_IN | \ + GPIOD_IS_OUT_ACTIVE) +#define GPIOD_MASK_DSTYPE (GPIOD_OPEN_DRAIN | GPIOD_OPEN_SOURCE) +#define GPIOD_MASK_PULL (GPIOD_PULL_UP | GPIOD_PULL_DOWN) + uint offset; /* GPIO offset within the device */ /* * We could consider adding the GPIO label in here. Possibly we could @@ -135,12 +141,6 @@ struct gpio_desc { */ }; -/* helper to compute the value of the gpio output */ -#define GPIOD_FLAGS_OUTPUT_MASK (GPIOD_ACTIVE_LOW | GPIOD_IS_OUT_ACTIVE) -#define GPIOD_FLAGS_OUTPUT(flags) \ - (((((flags) & GPIOD_FLAGS_OUTPUT_MASK) == GPIOD_IS_OUT_ACTIVE) || \ - (((flags) & GPIOD_FLAGS_OUTPUT_MASK) == GPIOD_ACTIVE_LOW))) - /** * dm_gpio_is_valid() - Check if a GPIO is valid * @@ -260,10 +260,32 @@ int gpio_xlate_offs_flags(struct udevice *dev, struct gpio_desc *desc, struct dm_gpio_ops { int (*request)(struct udevice *dev, unsigned offset, const char *label); int (*rfree)(struct udevice *dev, unsigned int offset); + + /** + * direction_input() - deprecated + * + * Equivalent to set_flags(...GPIOD_IS_IN) + */ int (*direction_input)(struct udevice *dev, unsigned offset); + + /** + * direction_output() - deprecated + * + * Equivalent to set_flags(...GPIOD_IS_OUT) with GPIOD_IS_OUT_ACTIVE + * also set if @value + */ int (*direction_output)(struct udevice *dev, unsigned offset, int value); + int (*get_value)(struct udevice *dev, unsigned offset); + + /** + * set_value() - Sets the GPIO value of an output + * + * If the driver provides an @set_flags() method then that is used + * in preference to this, with GPIOD_IS_OUT_ACTIVE set according to + * @value. + */ int (*set_value)(struct udevice *dev, unsigned offset, int value); /** * get_function() Get the GPIO function @@ -301,35 +323,54 @@ struct dm_gpio_ops { struct ofnode_phandle_args *args); /** - * set_dir_flags() - Set GPIO dir flags + * set_flags() - Adjust GPIO flags * * This function should set up the GPIO configuration according to the - * information provide by the direction flags bitfield. + * information provided by @flags. * - * This method is optional. + * If any flags cannot be set (e.g. the driver or hardware does not + * support them or this particular GPIO does not have the requested + * feature), the driver should return -EINVAL. + * + * The uclass checks that flags do not obviously conflict (e.g. input + * and output). If the driver finds other conflicts it should return + * -ERECALLCONFLICT + * + * Note that GPIOD_ACTIVE_LOW should be ignored, since the uclass + * adjusts for it automatically. For example, for an output GPIO, + * GPIOD_ACTIVE_LOW causes GPIOD_IS_OUT_ACTIVE to be inverted by the + * uclass, so the driver always sees the value that should be set at the + * pin (1=high, 0=low). + * + * This method is required and should be implemented by new drivers. At + * some point, it will supersede direction_input() and + * direction_output(), which wil be removed. * * @dev: GPIO device * @offset: GPIO offset within that device - * @flags: GPIO configuration to use - * @return 0 if OK, -ve on error + * @flags: New flags value (GPIOD_...) + * + * @return 0 if OK, -EINVAL if unsupported, -ERECALLCONFLICT if flags + * conflict in some * non-obvious way and were not applied, + * other -ve on error */ - int (*set_dir_flags)(struct udevice *dev, unsigned int offset, - ulong flags); + int (*set_flags)(struct udevice *dev, unsigned int offset, ulong flags); /** - * get_dir_flags() - Get GPIO dir flags + * get_flags() - Get GPIO flags * - * This function return the GPIO direction flags used. + * This function return the GPIO flags used. It should read this from + * the hardware directly. * * This method is optional. * * @dev: GPIO device * @offset: GPIO offset within that device - * @flags: place to put the used direction flags by GPIO + * @flagsp: place to put the current flags value * @return 0 if OK, -ve on error */ - int (*get_dir_flags)(struct udevice *dev, unsigned int offset, - ulong *flags); + int (*get_flags)(struct udevice *dev, unsigned int offset, + ulong *flagsp); #if CONFIG_IS_ENABLED(ACPIGEN) /** @@ -457,6 +498,31 @@ int gpio_get_values_as_int(const int *gpio_list); int dm_gpio_get_values_as_int(const struct gpio_desc *desc_list, int count); /** + * dm_gpio_get_values_as_int_base3() - Create a base-3 int from a list of GPIOs + * + * This uses pull-ups/pull-downs to figure out whether a GPIO line is externally + * pulled down, pulled up or floating. This allows three different strap values + * for each pin: + * 0 : external pull-down + * 1 : external pull-up + * 2 : floating + * + * With this it is possible to obtain more combinations from the same number of + * strapping pins, when compared to dm_gpio_get_values_as_int(). The external + * pull resistors should be made stronger that the internal SoC pull resistors, + * for this to work. + * + * With 2 pins, 6 combinations are possible, compared with 4 + * With 3 pins, 27 are possible, compared with 8 + * + * @desc_list: List of GPIOs to collect + * @count: Number of GPIOs + * @return resulting integer value, or -ve on error + */ +int dm_gpio_get_values_as_int_base3(struct gpio_desc *desc_list, + int count); + +/** * gpio_claim_vector() - claim a number of GPIOs for input * * @gpio_num_array: array of gpios to claim, terminated by -1 @@ -652,6 +718,25 @@ int dm_gpio_set_value(const struct gpio_desc *desc, int value); int dm_gpio_set_dir(struct gpio_desc *desc); /** + * dm_gpio_clrset_flags() - Update flags + * + * This updates the flags as directled. Note that desc->flags is updated by this + * function on success. If any changes cannot be made, best efforts are made. + * + * By use of @clr and @set any of flags can be individually updated, or left + * alone + * + * @desc: GPIO description containing device, offset and flags, + * previously returned by gpio_request_by_name() + * @clr: Flags to clear (GPIOD_...) + * @set: Flags to set (GPIOD_...) + * @return 0 if OK, -EINVAL if the flags had obvious conflicts, + * -ERECALLCONFLICT if there was a non-obvious hardware conflict when attempting + * to set the flags + */ +int dm_gpio_clrset_flags(struct gpio_desc *desc, ulong clr, ulong set); + +/** * dm_gpio_set_dir_flags() - Set direction using description and added flags * * This sets up the direction according to the provided flags and the GPIO @@ -666,16 +751,31 @@ int dm_gpio_set_dir(struct gpio_desc *desc); int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags); /** - * dm_gpio_get_dir_flags() - Get direction flags + * dm_gpios_clrset_flags() - Sets flags for a set of GPIOs + * + * This clears and sets flags individually for each GPIO. + * + * @desc: List of GPIOs to update + * @count: Number of GPIOs in the list + * @clr: Flags to clear (GPIOD_...), e.g. GPIOD_MASK_DIR if you are + * changing the direction + * @set: Flags to set (GPIOD_...) + * @return 0 if OK, -ve on error + */ +int dm_gpios_clrset_flags(struct gpio_desc *desc, int count, ulong clr, + ulong set); + +/** + * dm_gpio_get_flags() - Get flags * - * read the current direction flags + * Read the current flags * * @desc: GPIO description containing device, offset and flags, * previously returned by gpio_request_by_name() * @flags: place to put the used flags * @return 0 if OK, -ve on error, in which case desc->flags is not updated */ -int dm_gpio_get_dir_flags(struct gpio_desc *desc, ulong *flags); +int dm_gpio_get_flags(struct gpio_desc *desc, ulong *flags); /** * gpio_get_number() - Get the global GPIO number of a GPIO |