xref: /openbmc/linux/include/drm/gud.h (revision cf21eb6a)
1 /* SPDX-License-Identifier: MIT */
2 /*
3  * Copyright 2020 Noralf Trønnes
4  */
5 
6 #ifndef __LINUX_GUD_H
7 #define __LINUX_GUD_H
8 
9 #include <linux/types.h>
10 
11 /*
12  * struct gud_display_descriptor_req - Display descriptor
13  * @magic: Magic value GUD_DISPLAY_MAGIC
14  * @version: Protocol version
15  * @flags: Flags
16  *         - STATUS_ON_SET: Always do a status request after a SET request.
17  *                          This is used by the Linux gadget driver since it has
18  *                          no way to control the status stage of a control OUT
19  *                          request that has a payload.
20  *         - FULL_UPDATE:   Always send the entire framebuffer when flushing changes.
21  *                          The GUD_REQ_SET_BUFFER request will not be sent
22  *                          before each bulk transfer, it will only be sent if the
23  *                          previous bulk transfer had failed. This gives the device
24  *                          a chance to reset its state machine if needed.
25  *                          This flag can not be used in combination with compression.
26  * @compression: Supported compression types
27  *               - GUD_COMPRESSION_LZ4: LZ4 lossless compression.
28  * @max_buffer_size: Maximum buffer size the device can handle (optional).
29  *                   This is useful for devices that don't have a big enough
30  *                   buffer to decompress the entire framebuffer in one go.
31  * @min_width: Minimum pixel width the controller can handle
32  * @max_width: Maximum width
33  * @min_height: Minimum height
34  * @max_height: Maximum height
35  *
36  * Devices that have only one display mode will have min_width == max_width
37  * and min_height == max_height.
38  */
39 struct gud_display_descriptor_req {
40 	__le32 magic;
41 #define GUD_DISPLAY_MAGIC			0x1d50614d
42 	__u8 version;
43 	__le32 flags;
44 #define GUD_DISPLAY_FLAG_STATUS_ON_SET		BIT(0)
45 #define GUD_DISPLAY_FLAG_FULL_UPDATE		BIT(1)
46 	__u8 compression;
47 #define GUD_COMPRESSION_LZ4			BIT(0)
48 	__le32 max_buffer_size;
49 	__le32 min_width;
50 	__le32 max_width;
51 	__le32 min_height;
52 	__le32 max_height;
53 } __packed;
54 
55 /*
56  * struct gud_property_req - Property
57  * @prop: Property
58  * @val: Value
59  */
60 struct gud_property_req {
61 	__le16 prop;
62 	__le64 val;
63 } __packed;
64 
65 /*
66  * struct gud_display_mode_req - Display mode
67  * @clock: Pixel clock in kHz
68  * @hdisplay: Horizontal display size
69  * @hsync_start: Horizontal sync start
70  * @hsync_end: Horizontal sync end
71  * @htotal: Horizontal total size
72  * @vdisplay: Vertical display size
73  * @vsync_start: Vertical sync start
74  * @vsync_end: Vertical sync end
75  * @vtotal: Vertical total size
76  * @flags: Bits 0-13 are the same as in the RandR protocol and also what DRM uses.
77  *         The deprecated bits are reused for internal protocol flags leaving us
78  *         free to follow DRM for the other bits in the future.
79  *         - FLAG_PREFERRED: Set on the preferred display mode.
80  */
81 struct gud_display_mode_req {
82 	__le32 clock;
83 	__le16 hdisplay;
84 	__le16 hsync_start;
85 	__le16 hsync_end;
86 	__le16 htotal;
87 	__le16 vdisplay;
88 	__le16 vsync_start;
89 	__le16 vsync_end;
90 	__le16 vtotal;
91 	__le32 flags;
92 #define GUD_DISPLAY_MODE_FLAG_PHSYNC		BIT(0)
93 #define GUD_DISPLAY_MODE_FLAG_NHSYNC		BIT(1)
94 #define GUD_DISPLAY_MODE_FLAG_PVSYNC		BIT(2)
95 #define GUD_DISPLAY_MODE_FLAG_NVSYNC		BIT(3)
96 #define GUD_DISPLAY_MODE_FLAG_INTERLACE		BIT(4)
97 #define GUD_DISPLAY_MODE_FLAG_DBLSCAN		BIT(5)
98 #define GUD_DISPLAY_MODE_FLAG_CSYNC		BIT(6)
99 #define GUD_DISPLAY_MODE_FLAG_PCSYNC		BIT(7)
100 #define GUD_DISPLAY_MODE_FLAG_NCSYNC		BIT(8)
101 #define GUD_DISPLAY_MODE_FLAG_HSKEW		BIT(9)
102 /* BCast and PixelMultiplex are deprecated */
103 #define GUD_DISPLAY_MODE_FLAG_DBLCLK		BIT(12)
104 #define GUD_DISPLAY_MODE_FLAG_CLKDIV2		BIT(13)
105 #define GUD_DISPLAY_MODE_FLAG_USER_MASK		\
106 		(GUD_DISPLAY_MODE_FLAG_PHSYNC | GUD_DISPLAY_MODE_FLAG_NHSYNC | \
107 		GUD_DISPLAY_MODE_FLAG_PVSYNC | GUD_DISPLAY_MODE_FLAG_NVSYNC | \
108 		GUD_DISPLAY_MODE_FLAG_INTERLACE | GUD_DISPLAY_MODE_FLAG_DBLSCAN | \
109 		GUD_DISPLAY_MODE_FLAG_CSYNC | GUD_DISPLAY_MODE_FLAG_PCSYNC | \
110 		GUD_DISPLAY_MODE_FLAG_NCSYNC | GUD_DISPLAY_MODE_FLAG_HSKEW | \
111 		GUD_DISPLAY_MODE_FLAG_DBLCLK | GUD_DISPLAY_MODE_FLAG_CLKDIV2)
112 /* Internal protocol flags */
113 #define GUD_DISPLAY_MODE_FLAG_PREFERRED		BIT(10)
114 } __packed;
115 
116 /*
117  * struct gud_connector_descriptor_req - Connector descriptor
118  * @connector_type: Connector type (GUD_CONNECTOR_TYPE_*).
119  *                  If the host doesn't support the type it should fall back to PANEL.
120  * @flags: Flags
121  *         - POLL_STATUS: Connector status can change (polled every 10 seconds)
122  *         - INTERLACE: Interlaced modes are supported
123  *         - DOUBLESCAN: Doublescan modes are supported
124  */
125 struct gud_connector_descriptor_req {
126 	__u8 connector_type;
127 #define GUD_CONNECTOR_TYPE_PANEL		0
128 #define GUD_CONNECTOR_TYPE_VGA			1
129 #define GUD_CONNECTOR_TYPE_COMPOSITE		2
130 #define GUD_CONNECTOR_TYPE_SVIDEO		3
131 #define GUD_CONNECTOR_TYPE_COMPONENT		4
132 #define GUD_CONNECTOR_TYPE_DVI			5
133 #define GUD_CONNECTOR_TYPE_DISPLAYPORT		6
134 #define GUD_CONNECTOR_TYPE_HDMI			7
135 	__le32 flags;
136 #define GUD_CONNECTOR_FLAGS_POLL_STATUS		BIT(0)
137 #define GUD_CONNECTOR_FLAGS_INTERLACE		BIT(1)
138 #define GUD_CONNECTOR_FLAGS_DOUBLESCAN		BIT(2)
139 } __packed;
140 
141 /*
142  * struct gud_set_buffer_req - Set buffer transfer info
143  * @x: X position of rectangle
144  * @y: Y position
145  * @width: Pixel width of rectangle
146  * @height: Pixel height
147  * @length: Buffer length in bytes
148  * @compression: Transfer compression
149  * @compressed_length: Compressed buffer length
150  *
151  * This request is issued right before the bulk transfer.
152  * @x, @y, @width and @height specifies the rectangle where the buffer should be
153  * placed inside the framebuffer.
154  */
155 struct gud_set_buffer_req {
156 	__le32 x;
157 	__le32 y;
158 	__le32 width;
159 	__le32 height;
160 	__le32 length;
161 	__u8 compression;
162 	__le32 compressed_length;
163 } __packed;
164 
165 /*
166  * struct gud_state_req - Display state
167  * @mode: Display mode
168  * @format: Pixel format GUD_PIXEL_FORMAT_*
169  * @connector: Connector index
170  * @properties: Array of properties
171  *
172  * The entire state is transferred each time there's a change.
173  */
174 struct gud_state_req {
175 	struct gud_display_mode_req mode;
176 	__u8 format;
177 	__u8 connector;
178 	struct gud_property_req properties[];
179 } __packed;
180 
181 /* List of supported connector properties: */
182 
183 /* Margins in pixels to deal with overscan, range 0-100 */
184 #define GUD_PROPERTY_TV_LEFT_MARGIN			1
185 #define GUD_PROPERTY_TV_RIGHT_MARGIN			2
186 #define GUD_PROPERTY_TV_TOP_MARGIN			3
187 #define GUD_PROPERTY_TV_BOTTOM_MARGIN			4
188 #define GUD_PROPERTY_TV_MODE				5
189 /* Brightness in percent, range 0-100 */
190 #define GUD_PROPERTY_TV_BRIGHTNESS			6
191 /* Contrast in percent, range 0-100 */
192 #define GUD_PROPERTY_TV_CONTRAST			7
193 /* Flicker reduction in percent, range 0-100 */
194 #define GUD_PROPERTY_TV_FLICKER_REDUCTION		8
195 /* Overscan in percent, range 0-100 */
196 #define GUD_PROPERTY_TV_OVERSCAN			9
197 /* Saturation in percent, range 0-100 */
198 #define GUD_PROPERTY_TV_SATURATION			10
199 /* Hue in percent, range 0-100 */
200 #define GUD_PROPERTY_TV_HUE				11
201 
202 /*
203  * Backlight brightness is in the range 0-100 inclusive. The value represents the human perceptual
204  * brightness and not a linear PWM value. 0 is minimum brightness which should not turn the
205  * backlight completely off. The DPMS connector property should be used to control power which will
206  * trigger a GUD_REQ_SET_DISPLAY_ENABLE request.
207  *
208  * This does not map to a DRM property, it is used with the backlight device.
209  */
210 #define GUD_PROPERTY_BACKLIGHT_BRIGHTNESS		12
211 
212 /* List of supported properties that are not connector propeties: */
213 
214 /*
215  * Plane rotation. Should return the supported bitmask on
216  * GUD_REQ_GET_PROPERTIES. GUD_ROTATION_0 is mandatory.
217  *
218  * Note: This is not display rotation so 90/270 will need scaling to make it fit (unless squared).
219  */
220 #define GUD_PROPERTY_ROTATION				50
221   #define GUD_ROTATION_0			BIT(0)
222   #define GUD_ROTATION_90			BIT(1)
223   #define GUD_ROTATION_180			BIT(2)
224   #define GUD_ROTATION_270			BIT(3)
225   #define GUD_ROTATION_REFLECT_X		BIT(4)
226   #define GUD_ROTATION_REFLECT_Y		BIT(5)
227   #define GUD_ROTATION_MASK			(GUD_ROTATION_0 | GUD_ROTATION_90 | \
228 						GUD_ROTATION_180 | GUD_ROTATION_270 | \
229 						GUD_ROTATION_REFLECT_X | GUD_ROTATION_REFLECT_Y)
230 
231 /* USB Control requests: */
232 
233 /* Get status from the last GET/SET control request. Value is u8. */
234 #define GUD_REQ_GET_STATUS				0x00
235   /* Status values: */
236   #define GUD_STATUS_OK				0x00
237   #define GUD_STATUS_BUSY			0x01
238   #define GUD_STATUS_REQUEST_NOT_SUPPORTED	0x02
239   #define GUD_STATUS_PROTOCOL_ERROR		0x03
240   #define GUD_STATUS_INVALID_PARAMETER		0x04
241   #define GUD_STATUS_ERROR			0x05
242 
243 /* Get display descriptor as a &gud_display_descriptor_req */
244 #define GUD_REQ_GET_DESCRIPTOR				0x01
245 
246 /* Get supported pixel formats as a byte array of GUD_PIXEL_FORMAT_* */
247 #define GUD_REQ_GET_FORMATS				0x40
248   #define GUD_FORMATS_MAX_NUM			32
249   #define GUD_PIXEL_FORMAT_R1			0x01 /* 1-bit monochrome */
250   #define GUD_PIXEL_FORMAT_R8			0x08 /* 8-bit greyscale */
251   #define GUD_PIXEL_FORMAT_XRGB1111		0x20
252   #define GUD_PIXEL_FORMAT_RGB332		0x30
253   #define GUD_PIXEL_FORMAT_RGB565		0x40
254   #define GUD_PIXEL_FORMAT_RGB888		0x50
255   #define GUD_PIXEL_FORMAT_XRGB8888		0x80
256   #define GUD_PIXEL_FORMAT_ARGB8888		0x81
257 
258 /*
259  * Get supported properties that are not connector propeties as a &gud_property_req array.
260  * gud_property_req.val often contains the initial value for the property.
261  */
262 #define GUD_REQ_GET_PROPERTIES				0x41
263   #define GUD_PROPERTIES_MAX_NUM		32
264 
265 /* Connector requests have the connector index passed in the wValue field */
266 
267 /* Get connector descriptors as an array of &gud_connector_descriptor_req */
268 #define GUD_REQ_GET_CONNECTORS				0x50
269   #define GUD_CONNECTORS_MAX_NUM		32
270 
271 /*
272  * Get properties supported by the connector as a &gud_property_req array.
273  * gud_property_req.val often contains the initial value for the property.
274  */
275 #define GUD_REQ_GET_CONNECTOR_PROPERTIES		0x51
276   #define GUD_CONNECTOR_PROPERTIES_MAX_NUM	32
277 
278 /*
279  * Issued when there's a TV_MODE property present.
280  * Gets an array of the supported TV_MODE names each entry of length
281  * GUD_CONNECTOR_TV_MODE_NAME_LEN. Names must be NUL-terminated.
282  */
283 #define GUD_REQ_GET_CONNECTOR_TV_MODE_VALUES		0x52
284   #define GUD_CONNECTOR_TV_MODE_NAME_LEN	16
285   #define GUD_CONNECTOR_TV_MODE_MAX_NUM		16
286 
287 /* When userspace checks connector status, this is issued first, not used for poll requests. */
288 #define GUD_REQ_SET_CONNECTOR_FORCE_DETECT		0x53
289 
290 /*
291  * Get connector status. Value is u8.
292  *
293  * Userspace will get a HOTPLUG uevent if one of the following is true:
294  * - Connection status has changed since last
295  * - CHANGED is set
296  */
297 #define GUD_REQ_GET_CONNECTOR_STATUS			0x54
298   #define GUD_CONNECTOR_STATUS_DISCONNECTED	0x00
299   #define GUD_CONNECTOR_STATUS_CONNECTED	0x01
300   #define GUD_CONNECTOR_STATUS_UNKNOWN		0x02
301   #define GUD_CONNECTOR_STATUS_CONNECTED_MASK	0x03
302   #define GUD_CONNECTOR_STATUS_CHANGED		BIT(7)
303 
304 /*
305  * Display modes can be fetched as either EDID data or an array of &gud_display_mode_req.
306  *
307  * If GUD_REQ_GET_CONNECTOR_MODES returns zero, EDID is used to create display modes.
308  * If both display modes and EDID are returned, EDID is just passed on to userspace
309  * in the EDID connector property.
310  */
311 
312 /* Get &gud_display_mode_req array of supported display modes */
313 #define GUD_REQ_GET_CONNECTOR_MODES			0x55
314   #define GUD_CONNECTOR_MAX_NUM_MODES		128
315 
316 /* Get Extended Display Identification Data */
317 #define GUD_REQ_GET_CONNECTOR_EDID			0x56
318   #define GUD_CONNECTOR_MAX_EDID_LEN		2048
319 
320 /* Set buffer properties before bulk transfer as &gud_set_buffer_req */
321 #define GUD_REQ_SET_BUFFER				0x60
322 
323 /* Check display configuration as &gud_state_req */
324 #define GUD_REQ_SET_STATE_CHECK				0x61
325 
326 /* Apply the previous STATE_CHECK configuration */
327 #define GUD_REQ_SET_STATE_COMMIT			0x62
328 
329 /* Enable/disable the display controller, value is u8: 0/1 */
330 #define GUD_REQ_SET_CONTROLLER_ENABLE			0x63
331 
332 /* Enable/disable display/output (DPMS), value is u8: 0/1 */
333 #define GUD_REQ_SET_DISPLAY_ENABLE			0x64
334 
335 #endif
336