diff options
Diffstat (limited to 'Documentation/serial/driver')
| -rw-r--r-- | Documentation/serial/driver | 25 | 
1 files changed, 25 insertions, 0 deletions
| diff --git a/Documentation/serial/driver b/Documentation/serial/driver index c3a7689a90e6..3bba1aeb799c 100644 --- a/Documentation/serial/driver +++ b/Documentation/serial/driver @@ -429,3 +429,28 @@ thus:  		struct uart_port	port;  		int			my_stuff;  	}; + +Modem control lines via GPIO +---------------------------- + +Some helpers are provided in order to set/get modem control lines via GPIO. + +mctrl_gpio_init(dev, idx): +	This will get the {cts,rts,...}-gpios from device tree if they are +	present and request them, set direction etc, and return an +	allocated structure. devm_* functions are used, so there's no need +	to call mctrl_gpio_free(). + +mctrl_gpio_free(dev, gpios): +	This will free the requested gpios in mctrl_gpio_init(). +	As devm_* function are used, there's generally no need to call +	this function. + +mctrl_gpio_to_gpiod(gpios, gidx) +	This returns the gpio structure associated to the modem line index. + +mctrl_gpio_set(gpios, mctrl): +	This will sets the gpios according to the mctrl state. + +mctrl_gpio_get(gpios, mctrl): +	This will update mctrl with the gpios values. | 
