Commit | Line | Data |
---|---|---|
7e435aad RK |
1 | #include <linux/export.h> |
2 | #include <linux/list.h> | |
3 | #include <linux/of_graph.h> | |
4 | #include <drm/drmP.h> | |
5 | #include <drm/drm_crtc.h> | |
6 | #include <drm/drm_of.h> | |
7 | ||
8 | /** | |
9 | * drm_crtc_port_mask - find the mask of a registered CRTC by port OF node | |
10 | * @dev: DRM device | |
11 | * @port: port OF node | |
12 | * | |
13 | * Given a port OF node, return the possible mask of the corresponding | |
14 | * CRTC within a device's list of CRTCs. Returns zero if not found. | |
15 | */ | |
16 | static uint32_t drm_crtc_port_mask(struct drm_device *dev, | |
17 | struct device_node *port) | |
18 | { | |
19 | unsigned int index = 0; | |
20 | struct drm_crtc *tmp; | |
21 | ||
22 | list_for_each_entry(tmp, &dev->mode_config.crtc_list, head) { | |
23 | if (tmp->port == port) | |
24 | return 1 << index; | |
25 | ||
26 | index++; | |
27 | } | |
28 | ||
29 | return 0; | |
30 | } | |
31 | ||
32 | /** | |
33 | * drm_of_find_possible_crtcs - find the possible CRTCs for an encoder port | |
34 | * @dev: DRM device | |
35 | * @port: encoder port to scan for endpoints | |
36 | * | |
37 | * Scan all endpoints attached to a port, locate their attached CRTCs, | |
38 | * and generate the DRM mask of CRTCs which may be attached to this | |
39 | * encoder. | |
40 | * | |
41 | * See Documentation/devicetree/bindings/graph.txt for the bindings. | |
42 | */ | |
43 | uint32_t drm_of_find_possible_crtcs(struct drm_device *dev, | |
44 | struct device_node *port) | |
45 | { | |
46 | struct device_node *remote_port, *ep = NULL; | |
47 | uint32_t possible_crtcs = 0; | |
48 | ||
49 | do { | |
50 | ep = of_graph_get_next_endpoint(port, ep); | |
51 | if (!ep) | |
52 | break; | |
53 | ||
54 | remote_port = of_graph_get_remote_port(ep); | |
55 | if (!remote_port) { | |
56 | of_node_put(ep); | |
57 | return 0; | |
58 | } | |
59 | ||
60 | possible_crtcs |= drm_crtc_port_mask(dev, remote_port); | |
61 | ||
62 | of_node_put(remote_port); | |
63 | } while (1); | |
64 | ||
65 | return possible_crtcs; | |
66 | } | |
67 | EXPORT_SYMBOL(drm_of_find_possible_crtcs); |