1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ld9040 AMOLED LCD drm_panel driver.
4  *
5  * Copyright (c) 2014 Samsung Electronics Co., Ltd
6  * Derived from drivers/video/backlight/ld9040.c
7  *
8  * Andrzej Hajda <a.hajda@samsung.com>
9 */
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 #include <linux/spi/spi.h>
18 
19 #include <video/mipi_display.h>
20 #include <video/of_videomode.h>
21 #include <video/videomode.h>
22 
23 #include <drm/drm_modes.h>
24 #include <drm/drm_panel.h>
25 
26 /* Manufacturer Command Set */
27 #define MCS_MANPWR		0xb0
28 #define MCS_ELVSS_ON		0xb1
29 #define MCS_USER_SETTING	0xf0
30 #define MCS_DISPCTL		0xf2
31 #define MCS_POWER_CTRL		0xf4
32 #define MCS_GTCON		0xf7
33 #define MCS_PANEL_CONDITION	0xf8
34 #define MCS_GAMMA_SET1		0xf9
35 #define MCS_GAMMA_CTRL		0xfb
36 
37 /* array of gamma tables for gamma value 2.2 */
38 static u8 const ld9040_gammas[25][22] = {
39 	{ 0xf9, 0x00, 0x13, 0xb2, 0xba, 0xd2, 0x00, 0x30, 0x00, 0xaf, 0xc0,
40 	  0xb8, 0xcd, 0x00, 0x3d, 0x00, 0xa8, 0xb8, 0xb7, 0xcd, 0x00, 0x44 },
41 	{ 0xf9, 0x00, 0x13, 0xb9, 0xb9, 0xd0, 0x00, 0x3c, 0x00, 0xaf, 0xbf,
42 	  0xb6, 0xcb, 0x00, 0x4b, 0x00, 0xa8, 0xb9, 0xb5, 0xcc, 0x00, 0x52 },
43 	{ 0xf9, 0x00, 0x13, 0xba, 0xb9, 0xcd, 0x00, 0x41, 0x00, 0xb0, 0xbe,
44 	  0xb5, 0xc9, 0x00, 0x51, 0x00, 0xa9, 0xb9, 0xb5, 0xca, 0x00, 0x57 },
45 	{ 0xf9, 0x00, 0x13, 0xb9, 0xb8, 0xcd, 0x00, 0x46, 0x00, 0xb1, 0xbc,
46 	  0xb5, 0xc8, 0x00, 0x56, 0x00, 0xaa, 0xb8, 0xb4, 0xc9, 0x00, 0x5d },
47 	{ 0xf9, 0x00, 0x13, 0xba, 0xb8, 0xcb, 0x00, 0x4b, 0x00, 0xb3, 0xbc,
48 	  0xb4, 0xc7, 0x00, 0x5c, 0x00, 0xac, 0xb8, 0xb4, 0xc8, 0x00, 0x62 },
49 	{ 0xf9, 0x00, 0x13, 0xbb, 0xb7, 0xca, 0x00, 0x4f, 0x00, 0xb4, 0xbb,
50 	  0xb3, 0xc7, 0x00, 0x60, 0x00, 0xad, 0xb8, 0xb4, 0xc7, 0x00, 0x67 },
51 	{ 0xf9, 0x00, 0x47, 0xba, 0xb6, 0xca, 0x00, 0x53, 0x00, 0xb5, 0xbb,
52 	  0xb3, 0xc6, 0x00, 0x65, 0x00, 0xae, 0xb8, 0xb3, 0xc7, 0x00, 0x6c },
53 	{ 0xf9, 0x00, 0x71, 0xbb, 0xb5, 0xc8, 0x00, 0x57, 0x00, 0xb5, 0xbb,
54 	  0xb0, 0xc5, 0x00, 0x6a, 0x00, 0xae, 0xb9, 0xb1, 0xc6, 0x00, 0x70 },
55 	{ 0xf9, 0x00, 0x7b, 0xbb, 0xb4, 0xc8, 0x00, 0x5b, 0x00, 0xb5, 0xba,
56 	  0xb1, 0xc4, 0x00, 0x6e, 0x00, 0xae, 0xb9, 0xb0, 0xc5, 0x00, 0x75 },
57 	{ 0xf9, 0x00, 0x82, 0xba, 0xb4, 0xc7, 0x00, 0x5f, 0x00, 0xb5, 0xba,
58 	  0xb0, 0xc3, 0x00, 0x72, 0x00, 0xae, 0xb8, 0xb0, 0xc3, 0x00, 0x7a },
59 	{ 0xf9, 0x00, 0x89, 0xba, 0xb3, 0xc8, 0x00, 0x62, 0x00, 0xb6, 0xba,
60 	  0xaf, 0xc3, 0x00, 0x76, 0x00, 0xaf, 0xb7, 0xae, 0xc4, 0x00, 0x7e },
61 	{ 0xf9, 0x00, 0x8b, 0xb9, 0xb3, 0xc7, 0x00, 0x65, 0x00, 0xb7, 0xb8,
62 	  0xaf, 0xc3, 0x00, 0x7a, 0x00, 0x80, 0xb6, 0xae, 0xc4, 0x00, 0x81 },
63 	{ 0xf9, 0x00, 0x93, 0xba, 0xb3, 0xc5, 0x00, 0x69, 0x00, 0xb8, 0xb9,
64 	  0xae, 0xc1, 0x00, 0x7f, 0x00, 0xb0, 0xb6, 0xae, 0xc3, 0x00, 0x85 },
65 	{ 0xf9, 0x00, 0x97, 0xba, 0xb2, 0xc5, 0x00, 0x6c, 0x00, 0xb8, 0xb8,
66 	  0xae, 0xc1, 0x00, 0x82, 0x00, 0xb0, 0xb6, 0xae, 0xc2, 0x00, 0x89 },
67 	{ 0xf9, 0x00, 0x9a, 0xba, 0xb1, 0xc4, 0x00, 0x6f, 0x00, 0xb8, 0xb8,
68 	  0xad, 0xc0, 0x00, 0x86, 0x00, 0xb0, 0xb7, 0xad, 0xc0, 0x00, 0x8d },
69 	{ 0xf9, 0x00, 0x9c, 0xb9, 0xb0, 0xc4, 0x00, 0x72, 0x00, 0xb8, 0xb8,
70 	  0xac, 0xbf, 0x00, 0x8a, 0x00, 0xb0, 0xb6, 0xac, 0xc0, 0x00, 0x91 },
71 	{ 0xf9, 0x00, 0x9e, 0xba, 0xb0, 0xc2, 0x00, 0x75, 0x00, 0xb9, 0xb8,
72 	  0xab, 0xbe, 0x00, 0x8e, 0x00, 0xb0, 0xb6, 0xac, 0xbf, 0x00, 0x94 },
73 	{ 0xf9, 0x00, 0xa0, 0xb9, 0xaf, 0xc3, 0x00, 0x77, 0x00, 0xb9, 0xb7,
74 	  0xab, 0xbe, 0x00, 0x90, 0x00, 0xb0, 0xb6, 0xab, 0xbf, 0x00, 0x97 },
75 	{ 0xf9, 0x00, 0xa2, 0xb9, 0xaf, 0xc2, 0x00, 0x7a, 0x00, 0xb9, 0xb7,
76 	  0xaa, 0xbd, 0x00, 0x94, 0x00, 0xb0, 0xb5, 0xab, 0xbf, 0x00, 0x9a },
77 	{ 0xf9, 0x00, 0xa4, 0xb9, 0xaf, 0xc1, 0x00, 0x7d, 0x00, 0xb9, 0xb6,
78 	  0xaa, 0xbb, 0x00, 0x97, 0x00, 0xb1, 0xb5, 0xaa, 0xbf, 0x00, 0x9d },
79 	{ 0xf9, 0x00, 0xa4, 0xb8, 0xb0, 0xbf, 0x00, 0x80, 0x00, 0xb8, 0xb6,
80 	  0xaa, 0xbc, 0x00, 0x9a, 0x00, 0xb0, 0xb5, 0xab, 0xbd, 0x00, 0xa0 },
81 	{ 0xf9, 0x00, 0xa8, 0xb8, 0xae, 0xbe, 0x00, 0x84, 0x00, 0xb9, 0xb7,
82 	  0xa8, 0xbc, 0x00, 0x9d, 0x00, 0xb2, 0xb5, 0xaa, 0xbc, 0x00, 0xa4 },
83 	{ 0xf9, 0x00, 0xa9, 0xb6, 0xad, 0xbf, 0x00, 0x86, 0x00, 0xb8, 0xb5,
84 	  0xa8, 0xbc, 0x00, 0xa0, 0x00, 0xb3, 0xb3, 0xa9, 0xbc, 0x00, 0xa7 },
85 	{ 0xf9, 0x00, 0xa9, 0xb7, 0xae, 0xbd, 0x00, 0x89, 0x00, 0xb7, 0xb6,
86 	  0xa8, 0xba, 0x00, 0xa4, 0x00, 0xb1, 0xb4, 0xaa, 0xbb, 0x00, 0xaa },
87 	{ 0xf9, 0x00, 0xa7, 0xb4, 0xae, 0xbf, 0x00, 0x91, 0x00, 0xb2, 0xb4,
88 	  0xaa, 0xbb, 0x00, 0xac, 0x00, 0xb3, 0xb1, 0xaa, 0xbc, 0x00, 0xb3 },
89 };
90 
91 struct ld9040 {
92 	struct device *dev;
93 	struct drm_panel panel;
94 
95 	struct regulator_bulk_data supplies[2];
96 	struct gpio_desc *reset_gpio;
97 	u32 power_on_delay;
98 	u32 reset_delay;
99 	struct videomode vm;
100 	u32 width_mm;
101 	u32 height_mm;
102 
103 	int brightness;
104 
105 	/* This field is tested by functions directly accessing bus before
106 	 * transfer, transfer is skipped if it is set. In case of transfer
107 	 * failure or unexpected response the field is set to error value.
108 	 * Such construct allows to eliminate many checks in higher level
109 	 * functions.
110 	 */
111 	int error;
112 };
113 
114 static inline struct ld9040 *panel_to_ld9040(struct drm_panel *panel)
115 {
116 	return container_of(panel, struct ld9040, panel);
117 }
118 
119 static int ld9040_clear_error(struct ld9040 *ctx)
120 {
121 	int ret = ctx->error;
122 
123 	ctx->error = 0;
124 	return ret;
125 }
126 
127 static int ld9040_spi_write_word(struct ld9040 *ctx, u16 data)
128 {
129 	struct spi_device *spi = to_spi_device(ctx->dev);
130 	struct spi_transfer xfer = {
131 		.len		= 2,
132 		.tx_buf		= &data,
133 	};
134 	struct spi_message msg;
135 
136 	spi_message_init(&msg);
137 	spi_message_add_tail(&xfer, &msg);
138 
139 	return spi_sync(spi, &msg);
140 }
141 
142 static void ld9040_dcs_write(struct ld9040 *ctx, const u8 *data, size_t len)
143 {
144 	int ret = 0;
145 
146 	if (ctx->error < 0 || len == 0)
147 		return;
148 
149 	dev_dbg(ctx->dev, "writing dcs seq: %*ph\n", (int)len, data);
150 	ret = ld9040_spi_write_word(ctx, *data);
151 
152 	while (!ret && --len) {
153 		++data;
154 		ret = ld9040_spi_write_word(ctx, *data | 0x100);
155 	}
156 
157 	if (ret) {
158 		dev_err(ctx->dev, "error %d writing dcs seq: %*ph\n", ret,
159 			(int)len, data);
160 		ctx->error = ret;
161 	}
162 
163 	usleep_range(300, 310);
164 }
165 
166 #define ld9040_dcs_write_seq_static(ctx, seq...) \
167 ({\
168 	static const u8 d[] = { seq };\
169 	ld9040_dcs_write(ctx, d, ARRAY_SIZE(d));\
170 })
171 
172 static void ld9040_brightness_set(struct ld9040 *ctx)
173 {
174 	ld9040_dcs_write(ctx, ld9040_gammas[ctx->brightness],
175 			 ARRAY_SIZE(ld9040_gammas[ctx->brightness]));
176 
177 	ld9040_dcs_write_seq_static(ctx, MCS_GAMMA_CTRL, 0x02, 0x5a);
178 }
179 
180 static void ld9040_init(struct ld9040 *ctx)
181 {
182 	ld9040_dcs_write_seq_static(ctx, MCS_USER_SETTING, 0x5a, 0x5a);
183 	ld9040_dcs_write_seq_static(ctx, MCS_PANEL_CONDITION,
184 		0x05, 0x5e, 0x96, 0x6b, 0x7d, 0x0d, 0x3f, 0x00,
185 		0x00, 0x32, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
186 		0x07, 0x05, 0x1f, 0x1f, 0x1f, 0x00, 0x00);
187 	ld9040_dcs_write_seq_static(ctx, MCS_DISPCTL,
188 		0x02, 0x06, 0x0a, 0x10, 0x10);
189 	ld9040_dcs_write_seq_static(ctx, MCS_MANPWR, 0x04);
190 	ld9040_dcs_write_seq_static(ctx, MCS_POWER_CTRL,
191 		0x0a, 0x87, 0x25, 0x6a, 0x44, 0x02, 0x88);
192 	ld9040_dcs_write_seq_static(ctx, MCS_ELVSS_ON, 0x0f, 0x00, 0x16);
193 	ld9040_dcs_write_seq_static(ctx, MCS_GTCON, 0x09, 0x00, 0x00);
194 	ld9040_brightness_set(ctx);
195 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_EXIT_SLEEP_MODE);
196 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_ON);
197 }
198 
199 static int ld9040_power_on(struct ld9040 *ctx)
200 {
201 	int ret;
202 
203 	ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
204 	if (ret < 0)
205 		return ret;
206 
207 	msleep(ctx->power_on_delay);
208 	gpiod_set_value(ctx->reset_gpio, 0);
209 	msleep(ctx->reset_delay);
210 	gpiod_set_value(ctx->reset_gpio, 1);
211 	msleep(ctx->reset_delay);
212 
213 	return 0;
214 }
215 
216 static int ld9040_power_off(struct ld9040 *ctx)
217 {
218 	return regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
219 }
220 
221 static int ld9040_disable(struct drm_panel *panel)
222 {
223 	return 0;
224 }
225 
226 static int ld9040_unprepare(struct drm_panel *panel)
227 {
228 	struct ld9040 *ctx = panel_to_ld9040(panel);
229 
230 	msleep(120);
231 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_OFF);
232 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_ENTER_SLEEP_MODE);
233 	msleep(40);
234 
235 	ld9040_clear_error(ctx);
236 
237 	return ld9040_power_off(ctx);
238 }
239 
240 static int ld9040_prepare(struct drm_panel *panel)
241 {
242 	struct ld9040 *ctx = panel_to_ld9040(panel);
243 	int ret;
244 
245 	ret = ld9040_power_on(ctx);
246 	if (ret < 0)
247 		return ret;
248 
249 	ld9040_init(ctx);
250 
251 	ret = ld9040_clear_error(ctx);
252 
253 	if (ret < 0)
254 		ld9040_unprepare(panel);
255 
256 	return ret;
257 }
258 
259 static int ld9040_enable(struct drm_panel *panel)
260 {
261 	return 0;
262 }
263 
264 static int ld9040_get_modes(struct drm_panel *panel,
265 			    struct drm_connector *connector)
266 {
267 	struct ld9040 *ctx = panel_to_ld9040(panel);
268 	struct drm_display_mode *mode;
269 
270 	mode = drm_mode_create(connector->dev);
271 	if (!mode) {
272 		dev_err(panel->dev, "failed to create a new display mode\n");
273 		return 0;
274 	}
275 
276 	drm_display_mode_from_videomode(&ctx->vm, mode);
277 	mode->width_mm = ctx->width_mm;
278 	mode->height_mm = ctx->height_mm;
279 	connector->display_info.width_mm = mode->width_mm;
280 	connector->display_info.height_mm = mode->height_mm;
281 
282 	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
283 	drm_mode_probed_add(connector, mode);
284 
285 	return 1;
286 }
287 
288 static const struct drm_panel_funcs ld9040_drm_funcs = {
289 	.disable = ld9040_disable,
290 	.unprepare = ld9040_unprepare,
291 	.prepare = ld9040_prepare,
292 	.enable = ld9040_enable,
293 	.get_modes = ld9040_get_modes,
294 };
295 
296 static int ld9040_parse_dt(struct ld9040 *ctx)
297 {
298 	struct device *dev = ctx->dev;
299 	struct device_node *np = dev->of_node;
300 	int ret;
301 
302 	ret = of_get_videomode(np, &ctx->vm, 0);
303 	if (ret < 0)
304 		return ret;
305 
306 	of_property_read_u32(np, "power-on-delay", &ctx->power_on_delay);
307 	of_property_read_u32(np, "reset-delay", &ctx->reset_delay);
308 	of_property_read_u32(np, "panel-width-mm", &ctx->width_mm);
309 	of_property_read_u32(np, "panel-height-mm", &ctx->height_mm);
310 
311 	return 0;
312 }
313 
314 static int ld9040_bl_update_status(struct backlight_device *dev)
315 {
316 	struct ld9040 *ctx = bl_get_data(dev);
317 
318 	ctx->brightness = backlight_get_brightness(dev);
319 	ld9040_brightness_set(ctx);
320 
321 	return 0;
322 }
323 
324 static const struct backlight_ops ld9040_bl_ops = {
325 	.update_status  = ld9040_bl_update_status,
326 };
327 
328 static const struct backlight_properties ld9040_bl_props = {
329 	.type = BACKLIGHT_RAW,
330 	.scale = BACKLIGHT_SCALE_NON_LINEAR,
331 	.max_brightness = ARRAY_SIZE(ld9040_gammas) - 1,
332 	.brightness = ARRAY_SIZE(ld9040_gammas) - 1,
333 };
334 
335 static int ld9040_probe(struct spi_device *spi)
336 {
337 	struct backlight_device *bldev;
338 	struct device *dev = &spi->dev;
339 	struct ld9040 *ctx;
340 	int ret;
341 
342 	ctx = devm_kzalloc(dev, sizeof(struct ld9040), GFP_KERNEL);
343 	if (!ctx)
344 		return -ENOMEM;
345 
346 	spi_set_drvdata(spi, ctx);
347 
348 	ctx->dev = dev;
349 	ctx->brightness = ld9040_bl_props.brightness;
350 
351 	ret = ld9040_parse_dt(ctx);
352 	if (ret < 0)
353 		return ret;
354 
355 	ctx->supplies[0].supply = "vdd3";
356 	ctx->supplies[1].supply = "vci";
357 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ctx->supplies),
358 				      ctx->supplies);
359 	if (ret < 0)
360 		return ret;
361 
362 	ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
363 	if (IS_ERR(ctx->reset_gpio)) {
364 		dev_err(dev, "cannot get reset-gpios %ld\n",
365 			PTR_ERR(ctx->reset_gpio));
366 		return PTR_ERR(ctx->reset_gpio);
367 	}
368 
369 	spi->bits_per_word = 9;
370 	ret = spi_setup(spi);
371 	if (ret < 0) {
372 		dev_err(dev, "spi setup failed.\n");
373 		return ret;
374 	}
375 
376 	drm_panel_init(&ctx->panel, dev, &ld9040_drm_funcs,
377 		       DRM_MODE_CONNECTOR_DPI);
378 
379 	bldev = devm_backlight_device_register(dev, dev_name(dev), dev,
380 					       ctx, &ld9040_bl_ops,
381 					       &ld9040_bl_props);
382 	if (IS_ERR(bldev))
383 		return PTR_ERR(bldev);
384 
385 	drm_panel_add(&ctx->panel);
386 
387 	return 0;
388 }
389 
390 static void ld9040_remove(struct spi_device *spi)
391 {
392 	struct ld9040 *ctx = spi_get_drvdata(spi);
393 
394 	ld9040_power_off(ctx);
395 	drm_panel_remove(&ctx->panel);
396 }
397 
398 static const struct of_device_id ld9040_of_match[] = {
399 	{ .compatible = "samsung,ld9040" },
400 	{ }
401 };
402 MODULE_DEVICE_TABLE(of, ld9040_of_match);
403 
404 static const struct spi_device_id ld9040_ids[] = {
405 	{ "ld9040", },
406 	{ /* sentinel */ }
407 };
408 MODULE_DEVICE_TABLE(spi, ld9040_ids);
409 
410 static struct spi_driver ld9040_driver = {
411 	.probe = ld9040_probe,
412 	.remove = ld9040_remove,
413 	.id_table = ld9040_ids,
414 	.driver = {
415 		.name = "panel-samsung-ld9040",
416 		.of_match_table = ld9040_of_match,
417 	},
418 };
419 module_spi_driver(ld9040_driver);
420 
421 MODULE_AUTHOR("Andrzej Hajda <a.hajda@samsung.com>");
422 MODULE_DESCRIPTION("ld9040 LCD Driver");
423 MODULE_LICENSE("GPL v2");
424