1/*
2 * lws abstract display
3 *
4 * Copyright (C) 2019 - 2020 Andy Green <andy@warmcat.com>
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22 * IN THE SOFTWARE.
23 */
24
25#if !defined(__LWS_DISPLAY_H__)
26#define __LWS_DISPLAY_H__
27
28#include <stdint.h>
29
30typedef uint16_t lws_display_scalar;
31
32/*
33 * This is embedded in the actual display implementation object at the top,
34 * so a pointer to this can be cast to a pointer to the implementation object
35 * by any code that is specific to how it was implemented.
36 *
37 * Notice for the backlight / display intensity we contain pwm_ops... these can
38 * be some other pwm_ops like existing gpio pwm ops, or handled in a customized
39 * way like set oled contrast. Either way, the pwm level is arrived at via a
40 * full set of lws_led_sequences capable of generic lws transitions
41 */
42
43typedef struct lws_display {
44 int (*init)(const struct lws_display *disp);
45 const lws_pwm_ops_t *bl_pwm_ops;
46 int (*contrast)(const struct lws_display *disp, uint8_t contrast);
47 int (*blit)(const struct lws_display *disp, const uint8_t *src,
48 lws_display_scalar x, lws_display_scalar y,
49 lws_display_scalar w, lws_display_scalar h);
50 int (*power)(const struct lws_display *disp, int state);
51
52 const lws_led_sequence_def_t *bl_active;
53 const lws_led_sequence_def_t *bl_dim;
54 const lws_led_sequence_def_t *bl_transition;
55
56 void *variant;
57
58 int bl_index;
59
60 lws_display_scalar w;
61 /**< display surface width in pixels */
62 lws_display_scalar h;
63 /**< display surface height in pixels */
64
65 uint8_t latency_wake_ms;
66 /**< ms required after wake from sleep before display usable again...
67 * delay bringing up the backlight for this amount of time on wake.
68 * This is managed via a sul on the event loop, not blocking. */
69} lws_display_t;
70
71/*
72 * This contains dynamic data related to display state
73 */
74
75enum lws_display_controller_state {
76 LWSDISPS_OFF,
77 LWSDISPS_AUTODIMMED, /* is in pre- blanking static dim mode */
78 LWSDISPS_BECOMING_ACTIVE, /* waiting for wake latency before active */
79 LWSDISPS_ACTIVE, /* is active */
80 LWSDISPS_GOING_OFF /* dimming then off */
81};
82
83typedef struct lws_display_state {
84
85 lws_sorted_usec_list_t sul_autodim;
86 const lws_display_t *disp;
87 struct lws_context *ctx;
88
89 int autodim_ms;
90 int off_ms;
91
92 struct lws_led_state *bl_lcs;
93
94 lws_led_state_chs_t chs;
95 /* set of sequencer transition channels */
96
97 enum lws_display_controller_state state;
98
99} lws_display_state_t;
100
101/**
102 * lws_display_state_init() - initialize display states
103 *
104 * \param lds: the display state object
105 * \param ctx: the lws context
106 * \param autodim_ms: ms since last active report to dim display (<0 = never)
107 * \param off_ms: ms since dim to turn display off (<0 = never)
108 * \param bl_lcs: the led controller instance that has the backlight
109 * \param disp: generic display object we belong to
110 *
111 * This initializes a display's state, and sets up the optional screen auto-dim
112 * and blanking on inactive, and gradual brightness change timer.
113 *
114 * - auto-dim then off: set autodim to some ms and off_ms to some ms
115 * - auto-dim only: set autodim to some ms and off_ms to -1
116 * - off-only: set autodim to some ms and off_ms to 0
117 * - neither: set both autodim and off_ms to -1
118 */
119LWS_VISIBLE LWS_EXTERN void
120lws_display_state_init(lws_display_state_t *lds, struct lws_context *ctx,
121 int autodim_ms, int off_ms, struct lws_led_state *bl_lcs,
122 const lws_display_t *disp);
123
124/**
125 * lws_display_state_set_brightness() - gradually change the brightness
126 *
127 * \param lds: the display state we are changing
128 * \param target: the target brightness to transition to
129 *
130 * Adjusts the brightness gradually twoards the target at 20Hz
131 */
132LWS_VISIBLE LWS_EXTERN void
133lws_display_state_set_brightness(lws_display_state_t *lds,
134 const lws_led_sequence_def_t *pwmseq);
135
136/*
137 * lws_display_state_active() - inform the system the display is active
138 *
139 * \param lds: the display state we are marking as active
140 *
141 * Resets the auto-dim and auto-off timers and makes sure the display is on and
142 * at the active brightness level
143 */
144LWS_VISIBLE LWS_EXTERN void
145lws_display_state_active(lws_display_state_t *lds);
146
147/*
148 * lws_display_state_off() - turns off the related display
149 *
150 * \param lds: the display state we are turning off
151 *
152 * Turns the display to least power mode or completely off if possible.
153 * Disables the timers related to dimming and blanking.
154 */
155LWS_VISIBLE LWS_EXTERN void
156lws_display_state_off(lws_display_state_t *lds);
157
158#endif
159