1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * MIPI-DSI Sony ACX424AKP panel driver. This is a 480x864
4 * AMOLED panel with a command-only DSI interface.
5 *
6 * Copyright (C) Linaro Ltd. 2019
7 * Author: Linus Walleij
8 * Based on code and know-how from Marcus Lorentzon
9 * Copyright (C) ST-Ericsson SA 2010
10 */
11 #include <linux/backlight.h>
12 #include <linux/delay.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/regulator/consumer.h>
17
18 #include <video/mipi_display.h>
19
20 #include <drm/drm_mipi_dsi.h>
21 #include <drm/drm_modes.h>
22 #include <drm/drm_panel.h>
23
24 #define ACX424_DCS_READ_ID1 0xDA
25 #define ACX424_DCS_READ_ID2 0xDB
26 #define ACX424_DCS_READ_ID3 0xDC
27 #define ACX424_DCS_SET_MDDI 0xAE
28
29 /*
30 * Sony seems to use vendor ID 0x81
31 */
32 #define DISPLAY_SONY_ACX424AKP_ID1 0x811b
33 #define DISPLAY_SONY_ACX424AKP_ID2 0x811a
34 /*
35 * The third ID looks like a bug, vendor IDs begin at 0x80
36 * and panel 00 ... seems like default values.
37 */
38 #define DISPLAY_SONY_ACX424AKP_ID3 0x8000
39
40 struct acx424akp {
41 struct drm_panel panel;
42 struct device *dev;
43 struct backlight_device *bl;
44 struct regulator *supply;
45 struct gpio_desc *reset_gpio;
46 bool video_mode;
47 };
48
49 static const struct drm_display_mode sony_acx424akp_vid_mode = {
50 .clock = 27234,
51 .hdisplay = 480,
52 .hsync_start = 480 + 15,
53 .hsync_end = 480 + 15 + 0,
54 .htotal = 480 + 15 + 0 + 15,
55 .vdisplay = 864,
56 .vsync_start = 864 + 14,
57 .vsync_end = 864 + 14 + 1,
58 .vtotal = 864 + 14 + 1 + 11,
59 .width_mm = 48,
60 .height_mm = 84,
61 .flags = DRM_MODE_FLAG_PVSYNC,
62 };
63
64 /*
65 * The timings are not very helpful as the display is used in
66 * command mode using the maximum HS frequency.
67 */
68 static const struct drm_display_mode sony_acx424akp_cmd_mode = {
69 .clock = 35478,
70 .hdisplay = 480,
71 .hsync_start = 480 + 154,
72 .hsync_end = 480 + 154 + 16,
73 .htotal = 480 + 154 + 16 + 32,
74 .vdisplay = 864,
75 .vsync_start = 864 + 1,
76 .vsync_end = 864 + 1 + 1,
77 .vtotal = 864 + 1 + 1 + 1,
78 /*
79 * Some desired refresh rate, experiments at the maximum "pixel"
80 * clock speed (HS clock 420 MHz) yields around 117Hz.
81 */
82 .width_mm = 48,
83 .height_mm = 84,
84 };
85
panel_to_acx424akp(struct drm_panel * panel)86 static inline struct acx424akp *panel_to_acx424akp(struct drm_panel *panel)
87 {
88 return container_of(panel, struct acx424akp, panel);
89 }
90
91 #define FOSC 20 /* 20Mhz */
92 #define SCALE_FACTOR_NS_DIV_MHZ 1000
93
acx424akp_set_brightness(struct backlight_device * bl)94 static int acx424akp_set_brightness(struct backlight_device *bl)
95 {
96 struct acx424akp *acx = bl_get_data(bl);
97 struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
98 int period_ns = 1023;
99 int duty_ns = bl->props.brightness;
100 u8 pwm_ratio;
101 u8 pwm_div;
102 u8 par;
103 int ret;
104
105 /* Calculate the PWM duty cycle in n/256's */
106 pwm_ratio = max(((duty_ns * 256) / period_ns) - 1, 1);
107 pwm_div = max(1,
108 ((FOSC * period_ns) / 256) /
109 SCALE_FACTOR_NS_DIV_MHZ);
110
111 /* Set up PWM dutycycle ONE byte (differs from the standard) */
112 dev_dbg(acx->dev, "calculated duty cycle %02x\n", pwm_ratio);
113 ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
114 &pwm_ratio, 1);
115 if (ret < 0) {
116 dev_err(acx->dev, "failed to set display PWM ratio (%d)\n", ret);
117 return ret;
118 }
119
120 /*
121 * Sequence to write PWMDIV:
122 * address data
123 * 0xF3 0xAA CMD2 Unlock
124 * 0x00 0x01 Enter CMD2 page 0
125 * 0X7D 0x01 No reload MTP of CMD2 P1
126 * 0x22 PWMDIV
127 * 0x7F 0xAA CMD2 page 1 lock
128 */
129 par = 0xaa;
130 ret = mipi_dsi_dcs_write(dsi, 0xf3, &par, 1);
131 if (ret < 0) {
132 dev_err(acx->dev, "failed to unlock CMD 2 (%d)\n", ret);
133 return ret;
134 }
135 par = 0x01;
136 ret = mipi_dsi_dcs_write(dsi, 0x00, &par, 1);
137 if (ret < 0) {
138 dev_err(acx->dev, "failed to enter page 1 (%d)\n", ret);
139 return ret;
140 }
141 par = 0x01;
142 ret = mipi_dsi_dcs_write(dsi, 0x7d, &par, 1);
143 if (ret < 0) {
144 dev_err(acx->dev, "failed to disable MTP reload (%d)\n", ret);
145 return ret;
146 }
147 ret = mipi_dsi_dcs_write(dsi, 0x22, &pwm_div, 1);
148 if (ret < 0) {
149 dev_err(acx->dev, "failed to set PWM divisor (%d)\n", ret);
150 return ret;
151 }
152 par = 0xaa;
153 ret = mipi_dsi_dcs_write(dsi, 0x7f, &par, 1);
154 if (ret < 0) {
155 dev_err(acx->dev, "failed to lock CMD 2 (%d)\n", ret);
156 return ret;
157 }
158
159 /* Enable backlight */
160 par = 0x24;
161 ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
162 &par, 1);
163 if (ret < 0) {
164 dev_err(acx->dev, "failed to enable display backlight (%d)\n", ret);
165 return ret;
166 }
167
168 return 0;
169 }
170
171 static const struct backlight_ops acx424akp_bl_ops = {
172 .update_status = acx424akp_set_brightness,
173 };
174
acx424akp_read_id(struct acx424akp * acx)175 static int acx424akp_read_id(struct acx424akp *acx)
176 {
177 struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
178 u8 vendor, version, panel;
179 u16 val;
180 int ret;
181
182 ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID1, &vendor, 1);
183 if (ret < 0) {
184 dev_err(acx->dev, "could not vendor ID byte\n");
185 return ret;
186 }
187 ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID2, &version, 1);
188 if (ret < 0) {
189 dev_err(acx->dev, "could not read device version byte\n");
190 return ret;
191 }
192 ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID3, &panel, 1);
193 if (ret < 0) {
194 dev_err(acx->dev, "could not read panel ID byte\n");
195 return ret;
196 }
197
198 if (vendor == 0x00) {
199 dev_err(acx->dev, "device vendor ID is zero\n");
200 return -ENODEV;
201 }
202
203 val = (vendor << 8) | panel;
204 switch (val) {
205 case DISPLAY_SONY_ACX424AKP_ID1:
206 case DISPLAY_SONY_ACX424AKP_ID2:
207 case DISPLAY_SONY_ACX424AKP_ID3:
208 dev_info(acx->dev, "MTP vendor: %02x, version: %02x, panel: %02x\n",
209 vendor, version, panel);
210 break;
211 default:
212 dev_info(acx->dev, "unknown vendor: %02x, version: %02x, panel: %02x\n",
213 vendor, version, panel);
214 break;
215 }
216
217 return 0;
218 }
219
acx424akp_power_on(struct acx424akp * acx)220 static int acx424akp_power_on(struct acx424akp *acx)
221 {
222 int ret;
223
224 ret = regulator_enable(acx->supply);
225 if (ret) {
226 dev_err(acx->dev, "failed to enable supply (%d)\n", ret);
227 return ret;
228 }
229
230 /* Assert RESET */
231 gpiod_set_value_cansleep(acx->reset_gpio, 1);
232 udelay(20);
233 /* De-assert RESET */
234 gpiod_set_value_cansleep(acx->reset_gpio, 0);
235 usleep_range(11000, 20000);
236
237 return 0;
238 }
239
acx424akp_power_off(struct acx424akp * acx)240 static void acx424akp_power_off(struct acx424akp *acx)
241 {
242 /* Assert RESET */
243 gpiod_set_value_cansleep(acx->reset_gpio, 1);
244 usleep_range(11000, 20000);
245
246 regulator_disable(acx->supply);
247 }
248
acx424akp_prepare(struct drm_panel * panel)249 static int acx424akp_prepare(struct drm_panel *panel)
250 {
251 struct acx424akp *acx = panel_to_acx424akp(panel);
252 struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
253 const u8 mddi = 3;
254 int ret;
255
256 ret = acx424akp_power_on(acx);
257 if (ret)
258 return ret;
259
260 ret = acx424akp_read_id(acx);
261 if (ret) {
262 dev_err(acx->dev, "failed to read panel ID (%d)\n", ret);
263 goto err_power_off;
264 }
265
266 /* Enabe tearing mode: send TE (tearing effect) at VBLANK */
267 ret = mipi_dsi_dcs_set_tear_on(dsi,
268 MIPI_DSI_DCS_TEAR_MODE_VBLANK);
269 if (ret) {
270 dev_err(acx->dev, "failed to enable vblank TE (%d)\n", ret);
271 goto err_power_off;
272 }
273
274 /*
275 * Set MDDI
276 *
277 * This presumably deactivates the Qualcomm MDDI interface and
278 * selects DSI, similar code is found in other drivers such as the
279 * Sharp LS043T1LE01 which makes us suspect that this panel may be
280 * using a Novatek NT35565 or similar display driver chip that shares
281 * this command. Due to the lack of documentation we cannot know for
282 * sure.
283 */
284 ret = mipi_dsi_dcs_write(dsi, ACX424_DCS_SET_MDDI,
285 &mddi, sizeof(mddi));
286 if (ret < 0) {
287 dev_err(acx->dev, "failed to set MDDI (%d)\n", ret);
288 goto err_power_off;
289 }
290
291 /* Exit sleep mode */
292 ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
293 if (ret) {
294 dev_err(acx->dev, "failed to exit sleep mode (%d)\n", ret);
295 goto err_power_off;
296 }
297 msleep(140);
298
299 ret = mipi_dsi_dcs_set_display_on(dsi);
300 if (ret) {
301 dev_err(acx->dev, "failed to turn display on (%d)\n", ret);
302 goto err_power_off;
303 }
304 if (acx->video_mode) {
305 /* In video mode turn peripheral on */
306 ret = mipi_dsi_turn_on_peripheral(dsi);
307 if (ret) {
308 dev_err(acx->dev, "failed to turn on peripheral\n");
309 goto err_power_off;
310 }
311 }
312
313 acx->bl->props.power = FB_BLANK_NORMAL;
314
315 return 0;
316
317 err_power_off:
318 acx424akp_power_off(acx);
319 return ret;
320 }
321
acx424akp_unprepare(struct drm_panel * panel)322 static int acx424akp_unprepare(struct drm_panel *panel)
323 {
324 struct acx424akp *acx = panel_to_acx424akp(panel);
325 struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
326 u8 par;
327 int ret;
328
329 /* Disable backlight */
330 par = 0x00;
331 ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
332 &par, 1);
333 if (ret) {
334 dev_err(acx->dev, "failed to disable display backlight (%d)\n", ret);
335 return ret;
336 }
337
338 ret = mipi_dsi_dcs_set_display_off(dsi);
339 if (ret) {
340 dev_err(acx->dev, "failed to turn display off (%d)\n", ret);
341 return ret;
342 }
343
344 /* Enter sleep mode */
345 ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
346 if (ret) {
347 dev_err(acx->dev, "failed to enter sleep mode (%d)\n", ret);
348 return ret;
349 }
350 msleep(85);
351
352 acx424akp_power_off(acx);
353 acx->bl->props.power = FB_BLANK_POWERDOWN;
354
355 return 0;
356 }
357
acx424akp_enable(struct drm_panel * panel)358 static int acx424akp_enable(struct drm_panel *panel)
359 {
360 struct acx424akp *acx = panel_to_acx424akp(panel);
361
362 /*
363 * The backlight is on as long as the display is on
364 * so no use to call backlight_enable() here.
365 */
366 acx->bl->props.power = FB_BLANK_UNBLANK;
367
368 return 0;
369 }
370
acx424akp_disable(struct drm_panel * panel)371 static int acx424akp_disable(struct drm_panel *panel)
372 {
373 struct acx424akp *acx = panel_to_acx424akp(panel);
374
375 /*
376 * The backlight is on as long as the display is on
377 * so no use to call backlight_disable() here.
378 */
379 acx->bl->props.power = FB_BLANK_NORMAL;
380
381 return 0;
382 }
383
acx424akp_get_modes(struct drm_panel * panel,struct drm_connector * connector)384 static int acx424akp_get_modes(struct drm_panel *panel,
385 struct drm_connector *connector)
386 {
387 struct acx424akp *acx = panel_to_acx424akp(panel);
388 struct drm_display_mode *mode;
389
390 if (acx->video_mode)
391 mode = drm_mode_duplicate(connector->dev,
392 &sony_acx424akp_vid_mode);
393 else
394 mode = drm_mode_duplicate(connector->dev,
395 &sony_acx424akp_cmd_mode);
396 if (!mode) {
397 dev_err(panel->dev, "bad mode or failed to add mode\n");
398 return -EINVAL;
399 }
400 drm_mode_set_name(mode);
401 mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
402
403 connector->display_info.width_mm = mode->width_mm;
404 connector->display_info.height_mm = mode->height_mm;
405
406 drm_mode_probed_add(connector, mode);
407
408 return 1; /* Number of modes */
409 }
410
411 static const struct drm_panel_funcs acx424akp_drm_funcs = {
412 .disable = acx424akp_disable,
413 .unprepare = acx424akp_unprepare,
414 .prepare = acx424akp_prepare,
415 .enable = acx424akp_enable,
416 .get_modes = acx424akp_get_modes,
417 };
418
acx424akp_probe(struct mipi_dsi_device * dsi)419 static int acx424akp_probe(struct mipi_dsi_device *dsi)
420 {
421 struct device *dev = &dsi->dev;
422 struct acx424akp *acx;
423 int ret;
424
425 acx = devm_kzalloc(dev, sizeof(struct acx424akp), GFP_KERNEL);
426 if (!acx)
427 return -ENOMEM;
428 acx->video_mode = of_property_read_bool(dev->of_node,
429 "enforce-video-mode");
430
431 mipi_dsi_set_drvdata(dsi, acx);
432 acx->dev = dev;
433
434 dsi->lanes = 2;
435 dsi->format = MIPI_DSI_FMT_RGB888;
436 /*
437 * FIXME: these come from the ST-Ericsson vendor driver for the
438 * HREF520 and seems to reflect limitations in the PLLs on that
439 * platform, if you have the datasheet, please cross-check the
440 * actual max rates.
441 */
442 dsi->lp_rate = 19200000;
443 dsi->hs_rate = 420160000;
444
445 if (acx->video_mode)
446 /* Burst mode using event for sync */
447 dsi->mode_flags =
448 MIPI_DSI_MODE_VIDEO |
449 MIPI_DSI_MODE_VIDEO_BURST;
450 else
451 dsi->mode_flags =
452 MIPI_DSI_CLOCK_NON_CONTINUOUS |
453 MIPI_DSI_MODE_EOT_PACKET;
454
455 acx->supply = devm_regulator_get(dev, "vddi");
456 if (IS_ERR(acx->supply))
457 return PTR_ERR(acx->supply);
458
459 /* This asserts RESET by default */
460 acx->reset_gpio = devm_gpiod_get_optional(dev, "reset",
461 GPIOD_OUT_HIGH);
462 if (IS_ERR(acx->reset_gpio)) {
463 ret = PTR_ERR(acx->reset_gpio);
464 if (ret != -EPROBE_DEFER)
465 dev_err(dev, "failed to request GPIO (%d)\n", ret);
466 return ret;
467 }
468
469 drm_panel_init(&acx->panel, dev, &acx424akp_drm_funcs,
470 DRM_MODE_CONNECTOR_DSI);
471
472 acx->bl = devm_backlight_device_register(dev, "acx424akp", dev, acx,
473 &acx424akp_bl_ops, NULL);
474 if (IS_ERR(acx->bl)) {
475 dev_err(dev, "failed to register backlight device\n");
476 return PTR_ERR(acx->bl);
477 }
478 acx->bl->props.max_brightness = 1023;
479 acx->bl->props.brightness = 512;
480 acx->bl->props.power = FB_BLANK_POWERDOWN;
481
482 drm_panel_add(&acx->panel);
483
484 ret = mipi_dsi_attach(dsi);
485 if (ret < 0) {
486 drm_panel_remove(&acx->panel);
487 return ret;
488 }
489
490 return 0;
491 }
492
acx424akp_remove(struct mipi_dsi_device * dsi)493 static int acx424akp_remove(struct mipi_dsi_device *dsi)
494 {
495 struct acx424akp *acx = mipi_dsi_get_drvdata(dsi);
496
497 mipi_dsi_detach(dsi);
498 drm_panel_remove(&acx->panel);
499
500 return 0;
501 }
502
503 static const struct of_device_id acx424akp_of_match[] = {
504 { .compatible = "sony,acx424akp" },
505 { /* sentinel */ }
506 };
507 MODULE_DEVICE_TABLE(of, acx424akp_of_match);
508
509 static struct mipi_dsi_driver acx424akp_driver = {
510 .probe = acx424akp_probe,
511 .remove = acx424akp_remove,
512 .driver = {
513 .name = "panel-sony-acx424akp",
514 .of_match_table = acx424akp_of_match,
515 },
516 };
517 module_mipi_dsi_driver(acx424akp_driver);
518
519 MODULE_AUTHOR("Linus Wallei <linus.walleij@linaro.org>");
520 MODULE_DESCRIPTION("MIPI-DSI Sony acx424akp Panel Driver");
521 MODULE_LICENSE("GPL v2");
522
