diff options
Diffstat (limited to 'include/linux/gpio/driver.h')
| -rw-r--r-- | include/linux/gpio/driver.h | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index bee976f82788..50882e09289b 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -20,6 +20,18 @@ struct gpio_device; #ifdef CONFIG_GPIOLIB /** + * enum single_ended_mode - mode for single ended operation + * @LINE_MODE_PUSH_PULL: normal mode for a GPIO line, drive actively high/low + * @LINE_MODE_OPEN_DRAIN: set line to be open drain + * @LINE_MODE_OPEN_SOURCE: set line to be open source + */ +enum single_ended_mode { + LINE_MODE_PUSH_PULL, + LINE_MODE_OPEN_DRAIN, + LINE_MODE_OPEN_SOURCE, +}; + +/** * struct gpio_chip - abstract a GPIO controller * @label: a functional name for the GPIO device, such as a part * number or the name of the SoC IP-block implementing it. @@ -38,7 +50,15 @@ struct gpio_device; * @set: assigns output value for signal "offset" * @set_multiple: assigns output values for multiple signals defined by "mask" * @set_debounce: optional hook for setting debounce time for specified gpio in - * interrupt triggered gpio chips + * interrupt triggered gpio chips + * @set_single_ended: optional hook for setting a line as open drain, open + * source, or non-single ended (restore from open drain/source to normal + * push-pull mode) this should be implemented if the hardware supports + * open drain or open source settings. The GPIOlib will otherwise try + * to emulate open drain/source by not actively driving lines high/low + * if a consumer request this. The driver may return -ENOTSUPP if e.g. + * it supports just open drain but not open source and is called + * with LINE_MODE_OPEN_SOURCE as mode argument. * @to_irq: optional hook supporting non-static gpio_to_irq() mappings; * implementation may not sleep * @dbg_show: optional routine to show contents in debugfs; default code @@ -130,6 +150,9 @@ struct gpio_chip { int (*set_debounce)(struct gpio_chip *chip, unsigned offset, unsigned debounce); + int (*set_single_ended)(struct gpio_chip *chip, + unsigned offset, + enum single_ended_mode mode); int (*to_irq)(struct gpio_chip *chip, unsigned offset); |