1 
2 /**
3  * @file hal_disp.c
4  *
5  * @description HAL layer for display driver
6  *
7  */
8 
9 /*********************
10  *      INCLUDES
11  *********************/
12 #include <stdint.h>
13 #include <stddef.h>
14 #include "lv_hal.h"
15 #include "../lv_misc/lv_mem.h"
16 #include "../lv_core/lv_obj.h"
17 #include "../lv_core/lv_refr.h"
18 #include "../lv_misc/lv_gc.h"
19 
20 #if defined(LV_GC_INCLUDE)
21 #include LV_GC_INCLUDE
22 #endif /* LV_ENABLE_GC */
23 
24 /*********************
25  *      DEFINES
26  *********************/
27 
28 /**********************
29  *      TYPEDEFS
30  **********************/
31 
32 /**********************
33  *  STATIC PROTOTYPES
34  **********************/
35 
36 /**********************
37  *  STATIC VARIABLES
38  **********************/
39 static lv_disp_t * disp_def;
40 
41 /**********************
42  *      MACROS
43  **********************/
44 
45 /**********************
46  *   GLOBAL FUNCTIONS
47  **********************/
48 
49 /**
50  * Initialize a display driver with default values.
51  * It is used to surly have known values in the fields ant not memory junk.
52  * After it you can set the fields.
53  * @param driver pointer to driver variable to initialize
54  */
lv_disp_drv_init(lv_disp_drv_t * driver)55 void lv_disp_drv_init(lv_disp_drv_t * driver)
56 {
57     memset(driver, 0, sizeof(lv_disp_drv_t));
58 
59     driver->flush_cb         = NULL;
60     driver->hor_res          = LV_HOR_RES_MAX;
61     driver->ver_res          = LV_VER_RES_MAX;
62     driver->buffer           = NULL;
63     driver->rotated          = 0;
64     driver->color_chroma_key = LV_COLOR_TRANSP;
65 
66 #if LV_ANTIALIAS
67     driver->antialiasing = true;
68 #endif
69 
70 #if LV_COLOR_SCREEN_TRANSP
71     driver->screen_transp = 1;
72 #endif
73 
74 #if LV_USE_GPU
75     driver->gpu_blend_cb = NULL;
76     driver->gpu_fill_cb  = NULL;
77 #endif
78 
79 #if LV_USE_USER_DATA
80     driver->user_data = NULL;
81 #endif
82 
83     driver->set_px_cb = NULL;
84 }
85 
86 /**
87  * Initialize a display buffer
88  * @param disp_buf pointer `lv_disp_buf_t` variable to initialize
89  * @param buf1 A buffer to be used by LittlevGL to draw the image.
90  *             Always has to specified and can't be NULL.
91  *             Can be an array allocated by the user. E.g. `static lv_color_t disp_buf1[1024 * 10]`
92  *             Or a memory address e.g. in external SRAM
93  * @param buf2 Optionally specify a second buffer to make image rendering and image flushing
94  *             (sending to the display) parallel.
95  *             In the `disp_drv->flush` you should use DMA or similar hardware to send
96  *             the image to the display in the background.
97  *             It lets LittlevGL to render next frame into the other buffer while previous is being
98  * sent. Set to `NULL` if unused.
99  * @param size_in_px_cnt size of the `buf1` and `buf2` in pixel count.
100  */
lv_disp_buf_init(lv_disp_buf_t * disp_buf,void * buf1,void * buf2,uint32_t size_in_px_cnt)101 void lv_disp_buf_init(lv_disp_buf_t * disp_buf, void * buf1, void * buf2, uint32_t size_in_px_cnt)
102 {
103     memset(disp_buf, 0, sizeof(lv_disp_buf_t));
104 
105     disp_buf->buf1    = buf1;
106     disp_buf->buf2    = buf2;
107     disp_buf->buf_act = disp_buf->buf1;
108     disp_buf->size    = size_in_px_cnt;
109 }
110 
111 /**
112  * Register an initialized display driver.
113  * Automatically set the first display as active.
114  * @param driver pointer to an initialized 'lv_disp_drv_t' variable (can be local variable)
115  * @return pointer to the new display or NULL on error
116  */
lv_disp_drv_register(lv_disp_drv_t * driver)117 lv_disp_t * lv_disp_drv_register(lv_disp_drv_t * driver)
118 {
119     lv_disp_t * disp = lv_ll_ins_head(&LV_GC_ROOT(_lv_disp_ll));
120     if(!disp) {
121         lv_mem_assert(disp);
122         return NULL;
123     }
124 
125     memcpy(&disp->driver, driver, sizeof(lv_disp_drv_t));
126     memset(&disp->inv_area_joined, 0, sizeof(disp->inv_area_joined));
127     memset(&disp->inv_areas, 0, sizeof(disp->inv_areas));
128     lv_ll_init(&disp->scr_ll, sizeof(lv_obj_t));
129 
130     if(disp_def == NULL) disp_def = disp;
131 
132     lv_disp_t * disp_def_tmp = disp_def;
133     disp_def                 = disp; /*Temporarily change the default screen to create the default screens on the
134                                         new display*/
135 
136     disp->inv_p = 0;
137 
138     disp->act_scr   = lv_obj_create(NULL, NULL); /*Create a default screen on the display*/
139     disp->top_layer = lv_obj_create(NULL, NULL); /*Create top layer on the display*/
140     disp->sys_layer = lv_obj_create(NULL, NULL); /*Create top layer on the display*/
141     lv_obj_set_style(disp->top_layer, &lv_style_transp);
142     lv_obj_set_style(disp->sys_layer, &lv_style_transp);
143 
144     lv_obj_invalidate(disp->act_scr);
145 
146     disp_def = disp_def_tmp; /*Revert the default display*/
147 
148     /*Create a refresh task*/
149     disp->refr_task = lv_task_create(lv_disp_refr_task, LV_DISP_DEF_REFR_PERIOD, LV_TASK_PRIO_MID, disp);
150     lv_mem_assert(disp->refr_task);
151     if(disp->refr_task == NULL) return NULL;
152 
153     lv_task_ready(disp->refr_task); /*Be sure the screen will be refreshed immediately on start up*/
154 
155     return disp;
156 }
157 
158 /**
159  * Update the driver in run time.
160  * @param disp pointer to a display. (return value of `lv_disp_drv_register`)
161  * @param new_drv pointer to the new driver
162  */
lv_disp_drv_update(lv_disp_t * disp,lv_disp_drv_t * new_drv)163 void lv_disp_drv_update(lv_disp_t * disp, lv_disp_drv_t * new_drv)
164 {
165     memcpy(&disp->driver, new_drv, sizeof(lv_disp_drv_t));
166 
167     lv_obj_t * scr;
168     LV_LL_READ(disp->scr_ll, scr)
169     {
170         lv_obj_set_size(scr, lv_disp_get_hor_res(disp), lv_disp_get_ver_res(disp));
171     }
172 }
173 
174 /**
175  * Remove a display
176  * @param disp pointer to display
177  */
lv_disp_remove(lv_disp_t * disp)178 void lv_disp_remove(lv_disp_t * disp)
179 {
180     bool was_default = false;
181     if(disp == lv_disp_get_default()) was_default = true;
182 
183     /*Detach the input devices */
184     lv_indev_t * indev;
185     indev = lv_indev_get_next(NULL);
186     while(indev) {
187         if(indev->driver.disp == disp) {
188             indev->driver.disp = NULL;
189         }
190         indev = lv_indev_get_next(indev);
191     }
192 
193     lv_ll_rem(&LV_GC_ROOT(_lv_disp_ll), disp);
194     lv_mem_free(disp);
195 
196     if(was_default) lv_disp_set_default(lv_ll_get_head(&LV_GC_ROOT(_lv_disp_ll)));
197 }
198 
199 /**
200  * Set a default screen. The new screens will be created on it by default.
201  * @param disp pointer to a display
202  */
lv_disp_set_default(lv_disp_t * disp)203 void lv_disp_set_default(lv_disp_t * disp)
204 {
205     disp_def = disp;
206 }
207 
208 /**
209  * Get the default display
210  * @return pointer to the default display
211  */
lv_disp_get_default(void)212 lv_disp_t * lv_disp_get_default(void)
213 {
214     return disp_def;
215 }
216 
217 /**
218  * Get the horizontal resolution of a display
219  * @param disp pointer to a display (NULL to use the default display)
220  * @return the horizontal resolution of the display
221  */
lv_disp_get_hor_res(lv_disp_t * disp)222 lv_coord_t lv_disp_get_hor_res(lv_disp_t * disp)
223 {
224     if(disp == NULL) disp = lv_disp_get_default();
225 
226     if(disp == NULL)
227         return LV_HOR_RES_MAX;
228     else
229         return disp->driver.rotated == 0 ? disp->driver.hor_res : disp->driver.ver_res;
230 }
231 
232 /**
233  * Get the vertical resolution of a display
234  * @param disp pointer to a display (NULL to use the default display)
235  * @return the vertical resolution of the display
236  */
lv_disp_get_ver_res(lv_disp_t * disp)237 lv_coord_t lv_disp_get_ver_res(lv_disp_t * disp)
238 {
239     if(disp == NULL) disp = lv_disp_get_default();
240 
241     if(disp == NULL)
242         return LV_VER_RES_MAX;
243     else
244         return disp->driver.rotated == 0 ? disp->driver.ver_res : disp->driver.hor_res;
245 }
246 
247 /**
248  * Get if anti-aliasing is enabled for a display or not
249  * @param disp pointer to a display (NULL to use the default display)
250  * @return true: anti-aliasing is enabled; false: disabled
251  */
lv_disp_get_antialiasing(lv_disp_t * disp)252 bool lv_disp_get_antialiasing(lv_disp_t * disp)
253 {
254 #if LV_ANTIALIAS == 0
255     return false;
256 #else
257     if(disp == NULL) disp = lv_disp_get_default();
258     if(disp == NULL) return false;
259 
260     return disp->driver.antialiasing ? true : false;
261 #endif
262 }
263 
264 /**
265  * Call in the display driver's `flush_cb` function when the flushing is finished
266  * @param disp_drv pointer to display driver in `flush_cb` where this function is called
267  */
lv_disp_flush_ready(lv_disp_drv_t * disp_drv)268 LV_ATTRIBUTE_FLUSH_READY void lv_disp_flush_ready(lv_disp_drv_t * disp_drv)
269 {
270     disp_drv->buffer->flushing = 0;
271 
272     /*If the screen is transparent initialize it when the flushing is ready*/
273 #if LV_COLOR_SCREEN_TRANSP
274     if(disp_drv->screen_transp) {
275         memset(disp_drv->buffer->buf_act, 0x00, disp_drv->buffer->size * sizeof(lv_color32_t));
276     }
277 #endif
278 }
279 
280 /**
281  * Get the next display.
282  * @param disp pointer to the current display. NULL to initialize.
283  * @return the next display or NULL if no more. Give the first display when the parameter is NULL
284  */
lv_disp_get_next(lv_disp_t * disp)285 lv_disp_t * lv_disp_get_next(lv_disp_t * disp)
286 {
287     if(disp == NULL)
288         return lv_ll_get_head(&LV_GC_ROOT(_lv_disp_ll));
289     else
290         return lv_ll_get_next(&LV_GC_ROOT(_lv_disp_ll), disp);
291 }
292 
293 /**
294  * Get the internal buffer of a display
295  * @param disp pointer to a display
296  * @return pointer to the internal buffers
297  */
lv_disp_get_buf(lv_disp_t * disp)298 lv_disp_buf_t * lv_disp_get_buf(lv_disp_t * disp)
299 {
300     return disp->driver.buffer;
301 }
302 
303 /**
304  * Get the number of areas in the buffer
305  * @return number of invalid areas
306  */
lv_disp_get_inv_buf_size(lv_disp_t * disp)307 uint16_t lv_disp_get_inv_buf_size(lv_disp_t * disp)
308 {
309     return disp->inv_p;
310 }
311 
312 /**
313  * Pop (delete) the last 'num' invalidated areas from the buffer
314  * @param num number of areas to delete
315  */
lv_disp_pop_from_inv_buf(lv_disp_t * disp,uint16_t num)316 void lv_disp_pop_from_inv_buf(lv_disp_t * disp, uint16_t num)
317 {
318 
319     if(disp->inv_p < num)
320         disp->inv_p = 0;
321     else
322         disp->inv_p -= num;
323 }
324 
325 /**
326  * Check the driver configuration if it's double buffered (both `buf1` and `buf2` are set)
327  * @param disp pointer to to display to check
328  * @return true: double buffered; false: not double buffered
329  */
lv_disp_is_double_buf(lv_disp_t * disp)330 bool lv_disp_is_double_buf(lv_disp_t * disp)
331 {
332     if(disp->driver.buffer->buf1 && disp->driver.buffer->buf2)
333         return true;
334     else
335         return false;
336 }
337 
338 /**
339  * Check the driver configuration if it's TRUE double buffered (both `buf1` and `buf2` are set and
340  * `size` is screen sized)
341  * @param disp pointer to to display to check
342  * @return true: double buffered; false: not double buffered
343  */
lv_disp_is_true_double_buf(lv_disp_t * disp)344 bool lv_disp_is_true_double_buf(lv_disp_t * disp)
345 {
346     uint32_t scr_size = disp->driver.hor_res * disp->driver.ver_res;
347 
348     if(lv_disp_is_double_buf(disp) && disp->driver.buffer->size == scr_size) {
349         return true;
350     } else {
351         return false;
352     }
353 }
354 
355 /**********************
356  *   STATIC FUNCTIONS
357  **********************/
358