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 regulator *supply;
44 struct gpio_desc *reset_gpio;
45 bool video_mode;
46 };
47
48 static const struct drm_display_mode sony_acx424akp_vid_mode = {
49 .clock = 27234,
50 .hdisplay = 480,
51 .hsync_start = 480 + 15,
52 .hsync_end = 480 + 15 + 0,
53 .htotal = 480 + 15 + 0 + 15,
54 .vdisplay = 864,
55 .vsync_start = 864 + 14,
56 .vsync_end = 864 + 14 + 1,
57 .vtotal = 864 + 14 + 1 + 11,
58 .width_mm = 48,
59 .height_mm = 84,
60 .flags = DRM_MODE_FLAG_PVSYNC,
61 };
62
63 /*
64 * The timings are not very helpful as the display is used in
65 * command mode using the maximum HS frequency.
66 */
67 static const struct drm_display_mode sony_acx424akp_cmd_mode = {
68 .clock = 35478,
69 .hdisplay = 480,
70 .hsync_start = 480 + 154,
71 .hsync_end = 480 + 154 + 16,
72 .htotal = 480 + 154 + 16 + 32,
73 .vdisplay = 864,
74 .vsync_start = 864 + 1,
75 .vsync_end = 864 + 1 + 1,
76 .vtotal = 864 + 1 + 1 + 1,
77 /*
78 * Some desired refresh rate, experiments at the maximum "pixel"
79 * clock speed (HS clock 420 MHz) yields around 117Hz.
80 */
81 .width_mm = 48,
82 .height_mm = 84,
83 };
84
panel_to_acx424akp(struct drm_panel * panel)85 static inline struct acx424akp *panel_to_acx424akp(struct drm_panel *panel)
86 {
87 return container_of(panel, struct acx424akp, panel);
88 }
89
90 #define FOSC 20 /* 20Mhz */
91 #define SCALE_FACTOR_NS_DIV_MHZ 1000
92
acx424akp_set_brightness(struct backlight_device * bl)93 static int acx424akp_set_brightness(struct backlight_device *bl)
94 {
95 struct acx424akp *acx = bl_get_data(bl);
96 struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
97 int period_ns = 1023;
98 int duty_ns = bl->props.brightness;
99 u8 pwm_ratio;
100 u8 pwm_div;
101 u8 par;
102 int ret;
103
104 if (backlight_is_blank(bl)) {
105 /* Disable backlight */
106 par = 0x00;
107 ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
108 &par, 1);
109 if (ret) {
110 dev_err(acx->dev, "failed to disable display backlight (%d)\n", ret);
111 return ret;
112 }
113 return 0;
114 }
115
116 /* Calculate the PWM duty cycle in n/256's */
117 pwm_ratio = max(((duty_ns * 256) / period_ns) - 1, 1);
118 pwm_div = max(1,
119 ((FOSC * period_ns) / 256) /
120 SCALE_FACTOR_NS_DIV_MHZ);
121
122 /* Set up PWM dutycycle ONE byte (differs from the standard) */
123 dev_dbg(acx->dev, "calculated duty cycle %02x\n", pwm_ratio);
124 ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
125 &pwm_ratio, 1);
126 if (ret < 0) {
127 dev_err(acx->dev, "failed to set display PWM ratio (%d)\n", ret);
128 return ret;
129 }
130
131 /*
132 * Sequence to write PWMDIV:
133 * address data
134 * 0xF3 0xAA CMD2 Unlock
135 * 0x00 0x01 Enter CMD2 page 0
136 * 0X7D 0x01 No reload MTP of CMD2 P1
137 * 0x22 PWMDIV
138 * 0x7F 0xAA CMD2 page 1 lock
139 */
140 par = 0xaa;
141 ret = mipi_dsi_dcs_write(dsi, 0xf3, &par, 1);
142 if (ret < 0) {
143 dev_err(acx->dev, "failed to unlock CMD 2 (%d)\n", ret);
144 return ret;
145 }
146 par = 0x01;
147 ret = mipi_dsi_dcs_write(dsi, 0x00, &par, 1);
148 if (ret < 0) {
149 dev_err(acx->dev, "failed to enter page 1 (%d)\n", ret);
150 return ret;
151 }
152 par = 0x01;
153 ret = mipi_dsi_dcs_write(dsi, 0x7d, &par, 1);
154 if (ret < 0) {
155 dev_err(acx->dev, "failed to disable MTP reload (%d)\n", ret);
156 return ret;
157 }
158 ret = mipi_dsi_dcs_write(dsi, 0x22, &pwm_div, 1);
159 if (ret < 0) {
160 dev_err(acx->dev, "failed to set PWM divisor (%d)\n", ret);
161 return ret;
162 }
163 par = 0xaa;
164 ret = mipi_dsi_dcs_write(dsi, 0x7f, &par, 1);
165 if (ret < 0) {
166 dev_err(acx->dev, "failed to lock CMD 2 (%d)\n", ret);
167 return ret;
168 }
169
170 /* Enable backlight */
171 par = 0x24;
172 ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
173 &par, 1);
174 if (ret < 0) {
175 dev_err(acx->dev, "failed to enable display backlight (%d)\n", ret);
176 return ret;
177 }
178
179 return 0;
180 }
181
182 static const struct backlight_ops acx424akp_bl_ops = {
183 .update_status = acx424akp_set_brightness,
184 };
185
186 static const struct backlight_properties acx424akp_bl_props = {
187 .type = BACKLIGHT_RAW,
188 .brightness = 512,
189 .max_brightness = 1023,
190 };
191
acx424akp_read_id(struct acx424akp * acx)192 static int acx424akp_read_id(struct acx424akp *acx)
193 {
194 struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
195 u8 vendor, version, panel;
196 u16 val;
197 int ret;
198
199 ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID1, &vendor, 1);
200 if (ret < 0) {
201 dev_err(acx->dev, "could not vendor ID byte\n");
202 return ret;
203 }
204 ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID2, &version, 1);
205 if (ret < 0) {
206 dev_err(acx->dev, "could not read device version byte\n");
207 return ret;
208 }
209 ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID3, &panel, 1);
210 if (ret < 0) {
211 dev_err(acx->dev, "could not read panel ID byte\n");
212 return ret;
213 }
214
215 if (vendor == 0x00) {
216 dev_err(acx->dev, "device vendor ID is zero\n");
217 return -ENODEV;
218 }
219
220 val = (vendor << 8) | panel;
221 switch (val) {
222 case DISPLAY_SONY_ACX424AKP_ID1:
223 case DISPLAY_SONY_ACX424AKP_ID2:
224 case DISPLAY_SONY_ACX424AKP_ID3:
225 dev_info(acx->dev, "MTP vendor: %02x, version: %02x, panel: %02x\n",
226 vendor, version, panel);
227 break;
228 default:
229 dev_info(acx->dev, "unknown vendor: %02x, version: %02x, panel: %02x\n",
230 vendor, version, panel);
231 break;
232 }
233
234 return 0;
235 }
236
acx424akp_power_on(struct acx424akp * acx)237 static int acx424akp_power_on(struct acx424akp *acx)
238 {
239 int ret;
240
241 ret = regulator_enable(acx->supply);
242 if (ret) {
243 dev_err(acx->dev, "failed to enable supply (%d)\n", ret);
244 return ret;
245 }
246
247 /* Assert RESET */
248 gpiod_set_value_cansleep(acx->reset_gpio, 1);
249 udelay(20);
250 /* De-assert RESET */
251 gpiod_set_value_cansleep(acx->reset_gpio, 0);
252 usleep_range(11000, 20000);
253
254 return 0;
255 }
256
acx424akp_power_off(struct acx424akp * acx)257 static void acx424akp_power_off(struct acx424akp *acx)
258 {
259 /* Assert RESET */
260 gpiod_set_value_cansleep(acx->reset_gpio, 1);
261 usleep_range(11000, 20000);
262
263 regulator_disable(acx->supply);
264 }
265
acx424akp_prepare(struct drm_panel * panel)266 static int acx424akp_prepare(struct drm_panel *panel)
267 {
268 struct acx424akp *acx = panel_to_acx424akp(panel);
269 struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
270 const u8 mddi = 3;
271 int ret;
272
273 ret = acx424akp_power_on(acx);
274 if (ret)
275 return ret;
276
277 ret = acx424akp_read_id(acx);
278 if (ret) {
279 dev_err(acx->dev, "failed to read panel ID (%d)\n", ret);
280 goto err_power_off;
281 }
282
283 /* Enabe tearing mode: send TE (tearing effect) at VBLANK */
284 ret = mipi_dsi_dcs_set_tear_on(dsi,
285 MIPI_DSI_DCS_TEAR_MODE_VBLANK);
286 if (ret) {
287 dev_err(acx->dev, "failed to enable vblank TE (%d)\n", ret);
288 goto err_power_off;
289 }
290
291 /*
292 * Set MDDI
293 *
294 * This presumably deactivates the Qualcomm MDDI interface and
295 * selects DSI, similar code is found in other drivers such as the
296 * Sharp LS043T1LE01 which makes us suspect that this panel may be
297 * using a Novatek NT35565 or similar display driver chip that shares
298 * this command. Due to the lack of documentation we cannot know for
299 * sure.
300 */
301 ret = mipi_dsi_dcs_write(dsi, ACX424_DCS_SET_MDDI,
302 &mddi, sizeof(mddi));
303 if (ret < 0) {
304 dev_err(acx->dev, "failed to set MDDI (%d)\n", ret);
305 goto err_power_off;
306 }
307
308 /* Exit sleep mode */
309 ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
310 if (ret) {
311 dev_err(acx->dev, "failed to exit sleep mode (%d)\n", ret);
312 goto err_power_off;
313 }
314 msleep(140);
315
316 ret = mipi_dsi_dcs_set_display_on(dsi);
317 if (ret) {
318 dev_err(acx->dev, "failed to turn display on (%d)\n", ret);
319 goto err_power_off;
320 }
321 if (acx->video_mode) {
322 /* In video mode turn peripheral on */
323 ret = mipi_dsi_turn_on_peripheral(dsi);
324 if (ret) {
325 dev_err(acx->dev, "failed to turn on peripheral\n");
326 goto err_power_off;
327 }
328 }
329
330 return 0;
331
332 err_power_off:
333 acx424akp_power_off(acx);
334 return ret;
335 }
336
acx424akp_unprepare(struct drm_panel * panel)337 static int acx424akp_unprepare(struct drm_panel *panel)
338 {
339 struct acx424akp *acx = panel_to_acx424akp(panel);
340 struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
341 int ret;
342
343 ret = mipi_dsi_dcs_set_display_off(dsi);
344 if (ret) {
345 dev_err(acx->dev, "failed to turn display off (%d)\n", ret);
346 return ret;
347 }
348
349 /* Enter sleep mode */
350 ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
351 if (ret) {
352 dev_err(acx->dev, "failed to enter sleep mode (%d)\n", ret);
353 return ret;
354 }
355 msleep(85);
356
357 acx424akp_power_off(acx);
358
359 return 0;
360 }
361
362
acx424akp_get_modes(struct drm_panel * panel,struct drm_connector * connector)363 static int acx424akp_get_modes(struct drm_panel *panel,
364 struct drm_connector *connector)
365 {
366 struct acx424akp *acx = panel_to_acx424akp(panel);
367 struct drm_display_mode *mode;
368
369 if (acx->video_mode)
370 mode = drm_mode_duplicate(connector->dev,
371 &sony_acx424akp_vid_mode);
372 else
373 mode = drm_mode_duplicate(connector->dev,
374 &sony_acx424akp_cmd_mode);
375 if (!mode) {
376 dev_err(panel->dev, "bad mode or failed to add mode\n");
377 return -EINVAL;
378 }
379 drm_mode_set_name(mode);
380 mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
381
382 connector->display_info.width_mm = mode->width_mm;
383 connector->display_info.height_mm = mode->height_mm;
384
385 drm_mode_probed_add(connector, mode);
386
387 return 1; /* Number of modes */
388 }
389
390 static const struct drm_panel_funcs acx424akp_drm_funcs = {
391 .unprepare = acx424akp_unprepare,
392 .prepare = acx424akp_prepare,
393 .get_modes = acx424akp_get_modes,
394 };
395
acx424akp_probe(struct mipi_dsi_device * dsi)396 static int acx424akp_probe(struct mipi_dsi_device *dsi)
397 {
398 struct device *dev = &dsi->dev;
399 struct acx424akp *acx;
400 int ret;
401
402 acx = devm_kzalloc(dev, sizeof(struct acx424akp), GFP_KERNEL);
403 if (!acx)
404 return -ENOMEM;
405 acx->video_mode = of_property_read_bool(dev->of_node,
406 "enforce-video-mode");
407
408 mipi_dsi_set_drvdata(dsi, acx);
409 acx->dev = dev;
410
411 dsi->lanes = 2;
412 dsi->format = MIPI_DSI_FMT_RGB888;
413 /*
414 * FIXME: these come from the ST-Ericsson vendor driver for the
415 * HREF520 and seems to reflect limitations in the PLLs on that
416 * platform, if you have the datasheet, please cross-check the
417 * actual max rates.
418 */
419 dsi->lp_rate = 19200000;
420 dsi->hs_rate = 420160000;
421
422 if (acx->video_mode)
423 /* Burst mode using event for sync */
424 dsi->mode_flags =
425 MIPI_DSI_MODE_VIDEO |
426 MIPI_DSI_MODE_VIDEO_BURST;
427 else
428 dsi->mode_flags =
429 MIPI_DSI_CLOCK_NON_CONTINUOUS;
430
431 acx->supply = devm_regulator_get(dev, "vddi");
432 if (IS_ERR(acx->supply))
433 return PTR_ERR(acx->supply);
434
435 /* This asserts RESET by default */
436 acx->reset_gpio = devm_gpiod_get_optional(dev, "reset",
437 GPIOD_OUT_HIGH);
438 if (IS_ERR(acx->reset_gpio))
439 return dev_err_probe(dev, PTR_ERR(acx->reset_gpio),
440 "failed to request GPIO\n");
441
442 drm_panel_init(&acx->panel, dev, &acx424akp_drm_funcs,
443 DRM_MODE_CONNECTOR_DSI);
444
445 acx->panel.backlight = devm_backlight_device_register(dev, "acx424akp", dev, acx,
446 &acx424akp_bl_ops, &acx424akp_bl_props);
447 if (IS_ERR(acx->panel.backlight))
448 return dev_err_probe(dev, PTR_ERR(acx->panel.backlight),
449 "failed to register backlight device\n");
450
451 drm_panel_add(&acx->panel);
452
453 ret = mipi_dsi_attach(dsi);
454 if (ret < 0) {
455 drm_panel_remove(&acx->panel);
456 return ret;
457 }
458
459 return 0;
460 }
461
acx424akp_remove(struct mipi_dsi_device * dsi)462 static int acx424akp_remove(struct mipi_dsi_device *dsi)
463 {
464 struct acx424akp *acx = mipi_dsi_get_drvdata(dsi);
465
466 mipi_dsi_detach(dsi);
467 drm_panel_remove(&acx->panel);
468
469 return 0;
470 }
471
472 static const struct of_device_id acx424akp_of_match[] = {
473 { .compatible = "sony,acx424akp" },
474 { /* sentinel */ }
475 };
476 MODULE_DEVICE_TABLE(of, acx424akp_of_match);
477
478 static struct mipi_dsi_driver acx424akp_driver = {
479 .probe = acx424akp_probe,
480 .remove = acx424akp_remove,
481 .driver = {
482 .name = "panel-sony-acx424akp",
483 .of_match_table = acx424akp_of_match,
484 },
485 };
486 module_mipi_dsi_driver(acx424akp_driver);
487
488 MODULE_AUTHOR("Linus Wallei <linus.walleij@linaro.org>");
489 MODULE_DESCRIPTION("MIPI-DSI Sony acx424akp Panel Driver");
490 MODULE_LICENSE("GPL v2");
491