1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /* Copyright (C) 2013 Noralf Tronnes */
3
4 #ifndef __LINUX_FBTFT_H
5 #define __LINUX_FBTFT_H
6
7 #include <linux/fb.h>
8 #include <linux/spinlock.h>
9 #include <linux/spi/spi.h>
10 #include <linux/platform_device.h>
11
12 #define FBTFT_ONBOARD_BACKLIGHT 2
13
14 #define FBTFT_GPIO_NO_MATCH 0xFFFF
15 #define FBTFT_GPIO_NAME_SIZE 32
16 #define FBTFT_MAX_INIT_SEQUENCE 512
17 #define FBTFT_GAMMA_MAX_VALUES_TOTAL 128
18
19 #define FBTFT_OF_INIT_CMD BIT(24)
20 #define FBTFT_OF_INIT_DELAY BIT(25)
21
22 /**
23 * struct fbtft_gpio - Structure that holds one pinname to gpio mapping
24 * @name: pinname (reset, dc, etc.)
25 * @gpio: GPIO number
26 *
27 */
28 struct fbtft_gpio {
29 char name[FBTFT_GPIO_NAME_SIZE];
30 struct gpio_desc *gpio;
31 };
32
33 struct fbtft_par;
34
35 /**
36 * struct fbtft_ops - FBTFT operations structure
37 * @write: Writes to interface bus
38 * @read: Reads from interface bus
39 * @write_vmem: Writes video memory to display
40 * @write_reg: Writes to controller register
41 * @set_addr_win: Set the GRAM update window
42 * @reset: Reset the LCD controller
43 * @mkdirty: Marks display lines for update
44 * @update_display: Updates the display
45 * @init_display: Initializes the display
46 * @blank: Blank the display (optional)
47 * @request_gpios_match: Do pinname to gpio matching
48 * @request_gpios: Request gpios from the kernel
49 * @free_gpios: Free previously requested gpios
50 * @verify_gpios: Verify that necessary gpios is present (optional)
51 * @register_backlight: Used to register backlight device (optional)
52 * @unregister_backlight: Unregister backlight device (optional)
53 * @set_var: Configure LCD with values from variables like @rotate and @bgr
54 * (optional)
55 * @set_gamma: Set Gamma curve (optional)
56 *
57 * Most of these operations have default functions assigned to them in
58 * fbtft_framebuffer_alloc()
59 */
60 struct fbtft_ops {
61 int (*write)(struct fbtft_par *par, void *buf, size_t len);
62 int (*read)(struct fbtft_par *par, void *buf, size_t len);
63 int (*write_vmem)(struct fbtft_par *par, size_t offset, size_t len);
64 void (*write_register)(struct fbtft_par *par, int len, ...);
65
66 void (*set_addr_win)(struct fbtft_par *par,
67 int xs, int ys, int xe, int ye);
68 void (*reset)(struct fbtft_par *par);
69 void (*mkdirty)(struct fb_info *info, int from, int to);
70 void (*update_display)(struct fbtft_par *par,
71 unsigned int start_line, unsigned int end_line);
72 int (*init_display)(struct fbtft_par *par);
73 int (*blank)(struct fbtft_par *par, bool on);
74
75 unsigned long (*request_gpios_match)(struct fbtft_par *par,
76 const struct fbtft_gpio *gpio);
77 int (*request_gpios)(struct fbtft_par *par);
78 int (*verify_gpios)(struct fbtft_par *par);
79
80 void (*register_backlight)(struct fbtft_par *par);
81 void (*unregister_backlight)(struct fbtft_par *par);
82
83 int (*set_var)(struct fbtft_par *par);
84 int (*set_gamma)(struct fbtft_par *par, u32 *curves);
85 };
86
87 /**
88 * struct fbtft_display - Describes the display properties
89 * @width: Width of display in pixels
90 * @height: Height of display in pixels
91 * @regwidth: LCD Controller Register width in bits
92 * @buswidth: Display interface bus width in bits
93 * @backlight: Backlight type.
94 * @fbtftops: FBTFT operations provided by driver or device (platform_data)
95 * @bpp: Bits per pixel
96 * @fps: Frames per second
97 * @txbuflen: Size of transmit buffer
98 * @init_sequence: Pointer to LCD initialization array
99 * @gamma: String representation of Gamma curve(s)
100 * @gamma_num: Number of Gamma curves
101 * @gamma_len: Number of values per Gamma curve
102 * @debug: Initial debug value
103 *
104 * This structure is not stored by FBTFT except for init_sequence.
105 */
106 struct fbtft_display {
107 unsigned int width;
108 unsigned int height;
109 unsigned int regwidth;
110 unsigned int buswidth;
111 unsigned int backlight;
112 struct fbtft_ops fbtftops;
113 unsigned int bpp;
114 unsigned int fps;
115 int txbuflen;
116 const s16 *init_sequence;
117 char *gamma;
118 int gamma_num;
119 int gamma_len;
120 unsigned long debug;
121 };
122
123 /**
124 * struct fbtft_platform_data - Passes display specific data to the driver
125 * @display: Display properties
126 * @gpios: Pointer to an array of pinname to gpio mappings
127 * @rotate: Display rotation angle
128 * @bgr: LCD Controller BGR bit
129 * @fps: Frames per second (this will go away, use @fps in @fbtft_display)
130 * @txbuflen: Size of transmit buffer
131 * @startbyte: When set, enables use of Startbyte in transfers
132 * @gamma: String representation of Gamma curve(s)
133 * @extra: A way to pass extra info
134 */
135 struct fbtft_platform_data {
136 struct fbtft_display display;
137 unsigned int rotate;
138 bool bgr;
139 unsigned int fps;
140 int txbuflen;
141 u8 startbyte;
142 char *gamma;
143 void *extra;
144 };
145
146 /**
147 * struct fbtft_par - Main FBTFT data structure
148 *
149 * This structure holds all relevant data to operate the display
150 *
151 * See sourcefile for documentation since nested structs is not
152 * supported by kernel-doc.
153 *
154 */
155 /* @spi: Set if it is a SPI device
156 * @pdev: Set if it is a platform device
157 * @info: Pointer to framebuffer fb_info structure
158 * @pdata: Pointer to platform data
159 * @ssbuf: Not used
160 * @pseudo_palette: Used by fb_set_colreg()
161 * @txbuf.buf: Transmit buffer
162 * @txbuf.len: Transmit buffer length
163 * @buf: Small buffer used when writing init data over SPI
164 * @startbyte: Used by some controllers when in SPI mode.
165 * Format: 6 bit Device id + RS bit + RW bit
166 * @fbtftops: FBTFT operations provided by driver or device (platform_data)
167 * @dirty_lock: Protects dirty_lines_start and dirty_lines_end
168 * @dirty_lines_start: Where to begin updating display
169 * @dirty_lines_end: Where to end updating display
170 * @gpio.reset: GPIO used to reset display
171 * @gpio.dc: Data/Command signal, also known as RS
172 * @gpio.rd: Read latching signal
173 * @gpio.wr: Write latching signal
174 * @gpio.latch: Bus latch signal, eg. 16->8 bit bus latch
175 * @gpio.cs: LCD Chip Select with parallel interface bus
176 * @gpio.db[16]: Parallel databus
177 * @gpio.led[16]: Led control signals
178 * @gpio.aux[16]: Auxiliary signals, not used by core
179 * @init_sequence: Pointer to LCD initialization array
180 * @gamma.lock: Mutex for Gamma curve locking
181 * @gamma.curves: Pointer to Gamma curve array
182 * @gamma.num_values: Number of values per Gamma curve
183 * @gamma.num_curves: Number of Gamma curves
184 * @debug: Pointer to debug value
185 * @current_debug:
186 * @first_update_done: Used to only time the first display update
187 * @update_time: Used to calculate 'fps' in debug output
188 * @bgr: BGR mode/\n
189 * @extra: Extra info needed by driver
190 */
191 struct fbtft_par {
192 struct spi_device *spi;
193 struct platform_device *pdev;
194 struct fb_info *info;
195 struct fbtft_platform_data *pdata;
196 u16 *ssbuf;
197 u32 pseudo_palette[16];
198 struct {
199 void *buf;
200 size_t len;
201 } txbuf;
202 u8 *buf;
203 u8 startbyte;
204 struct fbtft_ops fbtftops;
205 spinlock_t dirty_lock;
206 unsigned int dirty_lines_start;
207 unsigned int dirty_lines_end;
208 struct {
209 struct gpio_desc *reset;
210 struct gpio_desc *dc;
211 struct gpio_desc *rd;
212 struct gpio_desc *wr;
213 struct gpio_desc *latch;
214 struct gpio_desc *cs;
215 struct gpio_desc *db[16];
216 struct gpio_desc *led[16];
217 struct gpio_desc *aux[16];
218 } gpio;
219 const s16 *init_sequence;
220 struct {
221 struct mutex lock;
222 u32 *curves;
223 int num_values;
224 int num_curves;
225 } gamma;
226 unsigned long debug;
227 bool first_update_done;
228 ktime_t update_time;
229 bool bgr;
230 void *extra;
231 bool polarity;
232 };
233
234 #define NUMARGS(...) (sizeof((int[]){__VA_ARGS__}) / sizeof(int))
235
236 #define write_reg(par, ...) \
237 ((par)->fbtftops.write_register(par, NUMARGS(__VA_ARGS__), __VA_ARGS__))
238
239 /* fbtft-core.c */
240 int fbtft_write_buf_dc(struct fbtft_par *par, void *buf, size_t len, int dc);
241 __printf(5, 6)
242 void fbtft_dbg_hex(const struct device *dev, int groupsize,
243 void *buf, size_t len, const char *fmt, ...);
244 struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
245 struct device *dev,
246 struct fbtft_platform_data *pdata);
247 void fbtft_framebuffer_release(struct fb_info *info);
248 int fbtft_register_framebuffer(struct fb_info *fb_info);
249 int fbtft_unregister_framebuffer(struct fb_info *fb_info);
250 void fbtft_register_backlight(struct fbtft_par *par);
251 void fbtft_unregister_backlight(struct fbtft_par *par);
252 int fbtft_init_display(struct fbtft_par *par);
253 int fbtft_probe_common(struct fbtft_display *display, struct spi_device *sdev,
254 struct platform_device *pdev);
255 int fbtft_remove_common(struct device *dev, struct fb_info *info);
256
257 /* fbtft-io.c */
258 int fbtft_write_spi(struct fbtft_par *par, void *buf, size_t len);
259 int fbtft_write_spi_emulate_9(struct fbtft_par *par, void *buf, size_t len);
260 int fbtft_read_spi(struct fbtft_par *par, void *buf, size_t len);
261 int fbtft_write_gpio8_wr(struct fbtft_par *par, void *buf, size_t len);
262 int fbtft_write_gpio16_wr(struct fbtft_par *par, void *buf, size_t len);
263 int fbtft_write_gpio16_wr_latched(struct fbtft_par *par, void *buf, size_t len);
264
265 /* fbtft-bus.c */
266 int fbtft_write_vmem8_bus8(struct fbtft_par *par, size_t offset, size_t len);
267 int fbtft_write_vmem16_bus16(struct fbtft_par *par, size_t offset, size_t len);
268 int fbtft_write_vmem16_bus8(struct fbtft_par *par, size_t offset, size_t len);
269 int fbtft_write_vmem16_bus9(struct fbtft_par *par, size_t offset, size_t len);
270 void fbtft_write_reg8_bus8(struct fbtft_par *par, int len, ...);
271 void fbtft_write_reg8_bus9(struct fbtft_par *par, int len, ...);
272 void fbtft_write_reg16_bus8(struct fbtft_par *par, int len, ...);
273 void fbtft_write_reg16_bus16(struct fbtft_par *par, int len, ...);
274
275 #define FBTFT_REGISTER_DRIVER(_name, _compatible, _display) \
276 \
277 static int fbtft_driver_probe_spi(struct spi_device *spi) \
278 { \
279 return fbtft_probe_common(_display, spi, NULL); \
280 } \
281 \
282 static int fbtft_driver_remove_spi(struct spi_device *spi) \
283 { \
284 struct fb_info *info = spi_get_drvdata(spi); \
285 \
286 return fbtft_remove_common(&spi->dev, info); \
287 } \
288 \
289 static int fbtft_driver_probe_pdev(struct platform_device *pdev) \
290 { \
291 return fbtft_probe_common(_display, NULL, pdev); \
292 } \
293 \
294 static int fbtft_driver_remove_pdev(struct platform_device *pdev) \
295 { \
296 struct fb_info *info = platform_get_drvdata(pdev); \
297 \
298 return fbtft_remove_common(&pdev->dev, info); \
299 } \
300 \
301 static const struct of_device_id dt_ids[] = { \
302 { .compatible = _compatible }, \
303 {}, \
304 }; \
305 \
306 MODULE_DEVICE_TABLE(of, dt_ids); \
307 \
308 \
309 static struct spi_driver fbtft_driver_spi_driver = { \
310 .driver = { \
311 .name = _name, \
312 .of_match_table = of_match_ptr(dt_ids), \
313 }, \
314 .probe = fbtft_driver_probe_spi, \
315 .remove = fbtft_driver_remove_spi, \
316 }; \
317 \
318 static struct platform_driver fbtft_driver_platform_driver = { \
319 .driver = { \
320 .name = _name, \
321 .owner = THIS_MODULE, \
322 .of_match_table = of_match_ptr(dt_ids), \
323 }, \
324 .probe = fbtft_driver_probe_pdev, \
325 .remove = fbtft_driver_remove_pdev, \
326 }; \
327 \
328 static int __init fbtft_driver_module_init(void) \
329 { \
330 int ret; \
331 \
332 ret = spi_register_driver(&fbtft_driver_spi_driver); \
333 if (ret < 0) \
334 return ret; \
335 return platform_driver_register(&fbtft_driver_platform_driver); \
336 } \
337 \
338 static void __exit fbtft_driver_module_exit(void) \
339 { \
340 spi_unregister_driver(&fbtft_driver_spi_driver); \
341 platform_driver_unregister(&fbtft_driver_platform_driver); \
342 } \
343 \
344 module_init(fbtft_driver_module_init); \
345 module_exit(fbtft_driver_module_exit);
346
347 /* Debug macros */
348
349 /* shorthand debug levels */
350 #define DEBUG_LEVEL_1 DEBUG_REQUEST_GPIOS
351 #define DEBUG_LEVEL_2 (DEBUG_LEVEL_1 | DEBUG_DRIVER_INIT_FUNCTIONS | DEBUG_TIME_FIRST_UPDATE)
352 #define DEBUG_LEVEL_3 (DEBUG_LEVEL_2 | DEBUG_RESET | DEBUG_INIT_DISPLAY | DEBUG_BLANK | DEBUG_REQUEST_GPIOS | DEBUG_FREE_GPIOS | DEBUG_VERIFY_GPIOS | DEBUG_BACKLIGHT | DEBUG_SYSFS)
353 #define DEBUG_LEVEL_4 (DEBUG_LEVEL_2 | DEBUG_FB_READ | DEBUG_FB_WRITE | DEBUG_FB_FILLRECT | DEBUG_FB_COPYAREA | DEBUG_FB_IMAGEBLIT | DEBUG_FB_BLANK)
354 #define DEBUG_LEVEL_5 (DEBUG_LEVEL_3 | DEBUG_UPDATE_DISPLAY)
355 #define DEBUG_LEVEL_6 (DEBUG_LEVEL_4 | DEBUG_LEVEL_5)
356 #define DEBUG_LEVEL_7 0xFFFFFFFF
357
358 #define DEBUG_DRIVER_INIT_FUNCTIONS BIT(3)
359 #define DEBUG_TIME_FIRST_UPDATE BIT(4)
360 #define DEBUG_TIME_EACH_UPDATE BIT(5)
361 #define DEBUG_DEFERRED_IO BIT(6)
362 #define DEBUG_FBTFT_INIT_FUNCTIONS BIT(7)
363
364 /* fbops */
365 #define DEBUG_FB_READ BIT(8)
366 #define DEBUG_FB_WRITE BIT(9)
367 #define DEBUG_FB_FILLRECT BIT(10)
368 #define DEBUG_FB_COPYAREA BIT(11)
369 #define DEBUG_FB_IMAGEBLIT BIT(12)
370 #define DEBUG_FB_SETCOLREG BIT(13)
371 #define DEBUG_FB_BLANK BIT(14)
372
373 #define DEBUG_SYSFS BIT(16)
374
375 /* fbtftops */
376 #define DEBUG_BACKLIGHT BIT(17)
377 #define DEBUG_READ BIT(18)
378 #define DEBUG_WRITE BIT(19)
379 #define DEBUG_WRITE_VMEM BIT(20)
380 #define DEBUG_WRITE_REGISTER BIT(21)
381 #define DEBUG_SET_ADDR_WIN BIT(22)
382 #define DEBUG_RESET BIT(23)
383 #define DEBUG_MKDIRTY BIT(24)
384 #define DEBUG_UPDATE_DISPLAY BIT(25)
385 #define DEBUG_INIT_DISPLAY BIT(26)
386 #define DEBUG_BLANK BIT(27)
387 #define DEBUG_REQUEST_GPIOS BIT(28)
388 #define DEBUG_FREE_GPIOS BIT(29)
389 #define DEBUG_REQUEST_GPIOS_MATCH BIT(30)
390 #define DEBUG_VERIFY_GPIOS BIT(31)
391
392 #define fbtft_init_dbg(dev, format, arg...) \
393 do { \
394 if (unlikely((dev)->platform_data && \
395 (((struct fbtft_platform_data *)(dev)->platform_data)->display.debug & DEBUG_DRIVER_INIT_FUNCTIONS))) \
396 dev_info(dev, format, ##arg); \
397 } while (0)
398
399 #define fbtft_par_dbg(level, par, format, arg...) \
400 do { \
401 if (unlikely(par->debug & level)) \
402 dev_info(par->info->device, format, ##arg); \
403 } while (0)
404
405 #define fbtft_par_dbg_hex(level, par, dev, type, buf, num, format, arg...) \
406 do { \
407 if (unlikely((par)->debug & (level))) \
408 fbtft_dbg_hex(dev, sizeof(type), buf,\
409 (num) * sizeof(type), format, ##arg); \
410 } while (0)
411
412 #endif /* __LINUX_FBTFT_H */