1/* SPDX-License-Identifier: MIT */
2/*
3 * Copyright 2020 Noralf Tr��nnes
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 */
39struct 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 */
60struct 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 */
81struct 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 */
125struct 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 */
155struct 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 */
174struct 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