backend/session: add docs

This commit is contained in:
Simon Ser 2024-01-31 19:01:13 +01:00
parent 5b08f91004
commit 967e788bc8
2 changed files with 30 additions and 5 deletions

View file

@ -445,9 +445,6 @@ static void find_gpus_handle_add(struct wl_listener *listener, void *data) {
handler->added = true;
}
/* Tries to find the primary GPU by checking for the "boot_vga" attribute.
* If it's not found, it returns the first valid GPU it finds.
*/
ssize_t wlr_session_find_gpus(struct wlr_session *session,
size_t ret_len, struct wlr_device **ret) {
const char *explicit = getenv("WLR_DRM_DEVICES");

View file

@ -7,11 +7,14 @@
struct libseat;
/**
* An opened physical device.
*/
struct wlr_device {
int fd;
int device_id;
dev_t dev;
struct wl_list link;
struct wl_list link; // wlr_session.devices
struct {
struct wl_signal change; // struct wlr_device_change_event
@ -19,6 +22,20 @@ struct wlr_device {
} events;
};
/**
* A session manages access to physical devices (such as GPUs and input
* devices).
*
* A session is only required when running on bare metal (e.g. with the KMS or
* libinput backends).
*
* The session listens for device hotplug events, and relays that information
* via the add_drm_card event and the change/remove events on struct wlr_device.
* The session provides functions to gain access to physical device (which is a
* privileged operation), see wlr_session_open_file(). The session also keeps
* track of the virtual terminal state (allowing users to switch between
* compositors or TTYs), see wlr_session_change_vt() and the active event.
*/
struct wlr_session {
/*
* Signal for when the session becomes active/inactive.
@ -40,7 +57,7 @@ struct wlr_session {
struct libseat *seat_handle;
struct wl_event_source *libseat_event;
struct wl_list devices;
struct wl_list devices; // wlr_device.link
struct wl_event_loop *event_loop;
struct wl_listener event_loop_destroy;
@ -114,6 +131,17 @@ void wlr_session_close_file(struct wlr_session *session,
*/
bool wlr_session_change_vt(struct wlr_session *session, unsigned vt);
/**
* Enumerate and open KMS devices.
*
* ret is filled with up to ret_len devices. The number of devices ret has been
* filled with is returned on success. If more devices than ret_len are probed,
* the extraneous ones are ignored. If there is no KMS device, the function
* will block until such device is detected up to a timeout. The first device
* returned is the default device (marked as "boot_vga" by the kernel).
*
* On error, or if no device was found, -1 is returned.
*/
ssize_t wlr_session_find_gpus(struct wlr_session *session,
size_t ret_len, struct wlr_device **ret);