Linux Device Drivers Development

The polled input device sub-class

A polled input device is a special type of input device, which relies on polling to sense device state changes whereas the generic input device type relies on the IRQ to sense changes and send events to the input core.

A polled input device is described as an instance of the struct input_polled_dev structure in the kernel, and is a wrapper around the generic struct input_dev structure:

struct input_polled_dev { void *private; void (*open)(struct input_polled_dev *dev); void (*close)(struct input_polled_dev *dev); void (*poll)(struct input_polled_dev *dev); unsigned int poll_interval; /* msec */ unsigned int poll_interval_max; /* msec */ unsigned int poll_interval_min; /* msec */ struct input_dev *input; bool ...