diff options
Diffstat (limited to 'Documentation/driver-api')
| -rw-r--r-- | Documentation/driver-api/gpio/board.rst | 16 | ||||
| -rw-r--r-- | Documentation/driver-api/gpio/drivers-on-gpio.rst | 4 |
2 files changed, 20 insertions, 0 deletions
diff --git a/Documentation/driver-api/gpio/board.rst b/Documentation/driver-api/gpio/board.rst index 25d62b2e9fd0..2c112553df84 100644 --- a/Documentation/driver-api/gpio/board.rst +++ b/Documentation/driver-api/gpio/board.rst @@ -177,3 +177,19 @@ mapping and is thus transparent to GPIO consumers. A set of functions such as gpiod_set_value() is available to work with the new descriptor-oriented interface. + +Boards using platform data can also hog GPIO lines by defining GPIO hog tables. + +.. code-block:: c + + struct gpiod_hog gpio_hog_table[] = { + GPIO_HOG("gpio.0", 10, "foo", GPIO_ACTIVE_LOW, GPIOD_OUT_HIGH), + { } + }; + +And the table can be added to the board code as follows:: + + gpiod_add_hogs(gpio_hog_table); + +The line will be hogged as soon as the gpiochip is created or - in case the +chip was created earlier - when the hog table is registered. diff --git a/Documentation/driver-api/gpio/drivers-on-gpio.rst b/Documentation/driver-api/gpio/drivers-on-gpio.rst index 7da0c1dd1f7a..f3a189320e11 100644 --- a/Documentation/driver-api/gpio/drivers-on-gpio.rst +++ b/Documentation/driver-api/gpio/drivers-on-gpio.rst @@ -85,6 +85,10 @@ hardware descriptions such as device tree or ACPI: any other serio bus to the system and makes it possible to connect drivers for e.g. keyboards and other PS/2 protocol based devices. +- cec-gpio: drivers/media/platform/cec-gpio/ is used to interact with a CEC + Consumer Electronics Control bus using only GPIO. It is used to communicate + with devices on the HDMI bus. + Apart from this there are special GPIO drivers in subsystems like MMC/SD to read card detect and write protect GPIO lines, and in the TTY serial subsystem to emulate MCTRL (modem control) signals CTS/RTS by using two GPIO lines. The |