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 <drm/drmP.h>
12 #include <drm/drm_panel.h>
13 
14 #include <linux/gpio/consumer.h>
15 #include <linux/regulator/consumer.h>
16 #include <linux/spi/spi.h>
17 
18 #include <video/mipi_display.h>
19 #include <video/of_videomode.h>
20 #include <video/videomode.h>
21 
22 /* Manufacturer Command Set */
23 #define MCS_MANPWR		0xb0
24 #define MCS_ELVSS_ON		0xb1
25 #define MCS_USER_SETTING	0xf0
26 #define MCS_DISPCTL		0xf2
27 #define MCS_POWER_CTRL		0xf4
28 #define MCS_GTCON		0xf7
29 #define MCS_PANEL_CONDITION	0xf8
30 #define MCS_GAMMA_SET1		0xf9
31 #define MCS_GAMMA_CTRL		0xfb
32 
33 /* array of gamma tables for gamma value 2.2 */
34 static u8 const ld9040_gammas[25][22] = {
35 	{ 0xf9, 0x00, 0x13, 0xb2, 0xba, 0xd2, 0x00, 0x30, 0x00, 0xaf, 0xc0,
36 	  0xb8, 0xcd, 0x00, 0x3d, 0x00, 0xa8, 0xb8, 0xb7, 0xcd, 0x00, 0x44 },
37 	{ 0xf9, 0x00, 0x13, 0xb9, 0xb9, 0xd0, 0x00, 0x3c, 0x00, 0xaf, 0xbf,
38 	  0xb6, 0xcb, 0x00, 0x4b, 0x00, 0xa8, 0xb9, 0xb5, 0xcc, 0x00, 0x52 },
39 	{ 0xf9, 0x00, 0x13, 0xba, 0xb9, 0xcd, 0x00, 0x41, 0x00, 0xb0, 0xbe,
40 	  0xb5, 0xc9, 0x00, 0x51, 0x00, 0xa9, 0xb9, 0xb5, 0xca, 0x00, 0x57 },
41 	{ 0xf9, 0x00, 0x13, 0xb9, 0xb8, 0xcd, 0x00, 0x46, 0x00, 0xb1, 0xbc,
42 	  0xb5, 0xc8, 0x00, 0x56, 0x00, 0xaa, 0xb8, 0xb4, 0xc9, 0x00, 0x5d },
43 	{ 0xf9, 0x00, 0x13, 0xba, 0xb8, 0xcb, 0x00, 0x4b, 0x00, 0xb3, 0xbc,
44 	  0xb4, 0xc7, 0x00, 0x5c, 0x00, 0xac, 0xb8, 0xb4, 0xc8, 0x00, 0x62 },
45 	{ 0xf9, 0x00, 0x13, 0xbb, 0xb7, 0xca, 0x00, 0x4f, 0x00, 0xb4, 0xbb,
46 	  0xb3, 0xc7, 0x00, 0x60, 0x00, 0xad, 0xb8, 0xb4, 0xc7, 0x00, 0x67 },
47 	{ 0xf9, 0x00, 0x47, 0xba, 0xb6, 0xca, 0x00, 0x53, 0x00, 0xb5, 0xbb,
48 	  0xb3, 0xc6, 0x00, 0x65, 0x00, 0xae, 0xb8, 0xb3, 0xc7, 0x00, 0x6c },
49 	{ 0xf9, 0x00, 0x71, 0xbb, 0xb5, 0xc8, 0x00, 0x57, 0x00, 0xb5, 0xbb,
50 	  0xb0, 0xc5, 0x00, 0x6a, 0x00, 0xae, 0xb9, 0xb1, 0xc6, 0x00, 0x70 },
51 	{ 0xf9, 0x00, 0x7b, 0xbb, 0xb4, 0xc8, 0x00, 0x5b, 0x00, 0xb5, 0xba,
52 	  0xb1, 0xc4, 0x00, 0x6e, 0x00, 0xae, 0xb9, 0xb0, 0xc5, 0x00, 0x75 },
53 	{ 0xf9, 0x00, 0x82, 0xba, 0xb4, 0xc7, 0x00, 0x5f, 0x00, 0xb5, 0xba,
54 	  0xb0, 0xc3, 0x00, 0x72, 0x00, 0xae, 0xb8, 0xb0, 0xc3, 0x00, 0x7a },
55 	{ 0xf9, 0x00, 0x89, 0xba, 0xb3, 0xc8, 0x00, 0x62, 0x00, 0xb6, 0xba,
56 	  0xaf, 0xc3, 0x00, 0x76, 0x00, 0xaf, 0xb7, 0xae, 0xc4, 0x00, 0x7e },
57 	{ 0xf9, 0x00, 0x8b, 0xb9, 0xb3, 0xc7, 0x00, 0x65, 0x00, 0xb7, 0xb8,
58 	  0xaf, 0xc3, 0x00, 0x7a, 0x00, 0x80, 0xb6, 0xae, 0xc4, 0x00, 0x81 },
59 	{ 0xf9, 0x00, 0x93, 0xba, 0xb3, 0xc5, 0x00, 0x69, 0x00, 0xb8, 0xb9,
60 	  0xae, 0xc1, 0x00, 0x7f, 0x00, 0xb0, 0xb6, 0xae, 0xc3, 0x00, 0x85 },
61 	{ 0xf9, 0x00, 0x97, 0xba, 0xb2, 0xc5, 0x00, 0x6c, 0x00, 0xb8, 0xb8,
62 	  0xae, 0xc1, 0x00, 0x82, 0x00, 0xb0, 0xb6, 0xae, 0xc2, 0x00, 0x89 },
63 	{ 0xf9, 0x00, 0x9a, 0xba, 0xb1, 0xc4, 0x00, 0x6f, 0x00, 0xb8, 0xb8,
64 	  0xad, 0xc0, 0x00, 0x86, 0x00, 0xb0, 0xb7, 0xad, 0xc0, 0x00, 0x8d },
65 	{ 0xf9, 0x00, 0x9c, 0xb9, 0xb0, 0xc4, 0x00, 0x72, 0x00, 0xb8, 0xb8,
66 	  0xac, 0xbf, 0x00, 0x8a, 0x00, 0xb0, 0xb6, 0xac, 0xc0, 0x00, 0x91 },
67 	{ 0xf9, 0x00, 0x9e, 0xba, 0xb0, 0xc2, 0x00, 0x75, 0x00, 0xb9, 0xb8,
68 	  0xab, 0xbe, 0x00, 0x8e, 0x00, 0xb0, 0xb6, 0xac, 0xbf, 0x00, 0x94 },
69 	{ 0xf9, 0x00, 0xa0, 0xb9, 0xaf, 0xc3, 0x00, 0x77, 0x00, 0xb9, 0xb7,
70 	  0xab, 0xbe, 0x00, 0x90, 0x00, 0xb0, 0xb6, 0xab, 0xbf, 0x00, 0x97 },
71 	{ 0xf9, 0x00, 0xa2, 0xb9, 0xaf, 0xc2, 0x00, 0x7a, 0x00, 0xb9, 0xb7,
72 	  0xaa, 0xbd, 0x00, 0x94, 0x00, 0xb0, 0xb5, 0xab, 0xbf, 0x00, 0x9a },
73 	{ 0xf9, 0x00, 0xa4, 0xb9, 0xaf, 0xc1, 0x00, 0x7d, 0x00, 0xb9, 0xb6,
74 	  0xaa, 0xbb, 0x00, 0x97, 0x00, 0xb1, 0xb5, 0xaa, 0xbf, 0x00, 0x9d },
75 	{ 0xf9, 0x00, 0xa4, 0xb8, 0xb0, 0xbf, 0x00, 0x80, 0x00, 0xb8, 0xb6,
76 	  0xaa, 0xbc, 0x00, 0x9a, 0x00, 0xb0, 0xb5, 0xab, 0xbd, 0x00, 0xa0 },
77 	{ 0xf9, 0x00, 0xa8, 0xb8, 0xae, 0xbe, 0x00, 0x84, 0x00, 0xb9, 0xb7,
78 	  0xa8, 0xbc, 0x00, 0x9d, 0x00, 0xb2, 0xb5, 0xaa, 0xbc, 0x00, 0xa4 },
79 	{ 0xf9, 0x00, 0xa9, 0xb6, 0xad, 0xbf, 0x00, 0x86, 0x00, 0xb8, 0xb5,
80 	  0xa8, 0xbc, 0x00, 0xa0, 0x00, 0xb3, 0xb3, 0xa9, 0xbc, 0x00, 0xa7 },
81 	{ 0xf9, 0x00, 0xa9, 0xb7, 0xae, 0xbd, 0x00, 0x89, 0x00, 0xb7, 0xb6,
82 	  0xa8, 0xba, 0x00, 0xa4, 0x00, 0xb1, 0xb4, 0xaa, 0xbb, 0x00, 0xaa },
83 	{ 0xf9, 0x00, 0xa7, 0xb4, 0xae, 0xbf, 0x00, 0x91, 0x00, 0xb2, 0xb4,
84 	  0xaa, 0xbb, 0x00, 0xac, 0x00, 0xb3, 0xb1, 0xaa, 0xbc, 0x00, 0xb3 },
85 };
86 
87 struct ld9040 {
88 	struct device *dev;
89 	struct drm_panel panel;
90 
91 	struct regulator_bulk_data supplies[2];
92 	struct gpio_desc *reset_gpio;
93 	u32 power_on_delay;
94 	u32 reset_delay;
95 	struct videomode vm;
96 	u32 width_mm;
97 	u32 height_mm;
98 
99 	int brightness;
100 
101 	/* This field is tested by functions directly accessing bus before
102 	 * transfer, transfer is skipped if it is set. In case of transfer
103 	 * failure or unexpected response the field is set to error value.
104 	 * Such construct allows to eliminate many checks in higher level
105 	 * functions.
106 	 */
107 	int error;
108 };
109 
110 static inline struct ld9040 *panel_to_ld9040(struct drm_panel *panel)
111 {
112 	return container_of(panel, struct ld9040, panel);
113 }
114 
115 static int ld9040_clear_error(struct ld9040 *ctx)
116 {
117 	int ret = ctx->error;
118 
119 	ctx->error = 0;
120 	return ret;
121 }
122 
123 static int ld9040_spi_write_word(struct ld9040 *ctx, u16 data)
124 {
125 	struct spi_device *spi = to_spi_device(ctx->dev);
126 	struct spi_transfer xfer = {
127 		.len		= 2,
128 		.tx_buf		= &data,
129 	};
130 	struct spi_message msg;
131 
132 	spi_message_init(&msg);
133 	spi_message_add_tail(&xfer, &msg);
134 
135 	return spi_sync(spi, &msg);
136 }
137 
138 static void ld9040_dcs_write(struct ld9040 *ctx, const u8 *data, size_t len)
139 {
140 	int ret = 0;
141 
142 	if (ctx->error < 0 || len == 0)
143 		return;
144 
145 	dev_dbg(ctx->dev, "writing dcs seq: %*ph\n", (int)len, data);
146 	ret = ld9040_spi_write_word(ctx, *data);
147 
148 	while (!ret && --len) {
149 		++data;
150 		ret = ld9040_spi_write_word(ctx, *data | 0x100);
151 	}
152 
153 	if (ret) {
154 		dev_err(ctx->dev, "error %d writing dcs seq: %*ph\n", ret,
155 			(int)len, data);
156 		ctx->error = ret;
157 	}
158 
159 	usleep_range(300, 310);
160 }
161 
162 #define ld9040_dcs_write_seq_static(ctx, seq...) \
163 ({\
164 	static const u8 d[] = { seq };\
165 	ld9040_dcs_write(ctx, d, ARRAY_SIZE(d));\
166 })
167 
168 static void ld9040_brightness_set(struct ld9040 *ctx)
169 {
170 	ld9040_dcs_write(ctx, ld9040_gammas[ctx->brightness],
171 			 ARRAY_SIZE(ld9040_gammas[ctx->brightness]));
172 
173 	ld9040_dcs_write_seq_static(ctx, MCS_GAMMA_CTRL, 0x02, 0x5a);
174 }
175 
176 static void ld9040_init(struct ld9040 *ctx)
177 {
178 	ld9040_dcs_write_seq_static(ctx, MCS_USER_SETTING, 0x5a, 0x5a);
179 	ld9040_dcs_write_seq_static(ctx, MCS_PANEL_CONDITION,
180 		0x05, 0x65, 0x96, 0x71, 0x7d, 0x19, 0x3b, 0x0d,
181 		0x19, 0x7e, 0x0d, 0xe2, 0x00, 0x00, 0x7e, 0x7d,
182 		0x07, 0x07, 0x20, 0x20, 0x20, 0x02, 0x02);
183 	ld9040_dcs_write_seq_static(ctx, MCS_DISPCTL,
184 		0x02, 0x08, 0x08, 0x10, 0x10);
185 	ld9040_dcs_write_seq_static(ctx, MCS_MANPWR, 0x04);
186 	ld9040_dcs_write_seq_static(ctx, MCS_POWER_CTRL,
187 		0x0a, 0x87, 0x25, 0x6a, 0x44, 0x02, 0x88);
188 	ld9040_dcs_write_seq_static(ctx, MCS_ELVSS_ON, 0x0d, 0x00, 0x16);
189 	ld9040_dcs_write_seq_static(ctx, MCS_GTCON, 0x09, 0x00, 0x00);
190 	ld9040_brightness_set(ctx);
191 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_EXIT_SLEEP_MODE);
192 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_ON);
193 }
194 
195 static int ld9040_power_on(struct ld9040 *ctx)
196 {
197 	int ret;
198 
199 	ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
200 	if (ret < 0)
201 		return ret;
202 
203 	msleep(ctx->power_on_delay);
204 	gpiod_set_value(ctx->reset_gpio, 0);
205 	msleep(ctx->reset_delay);
206 	gpiod_set_value(ctx->reset_gpio, 1);
207 	msleep(ctx->reset_delay);
208 
209 	return 0;
210 }
211 
212 static int ld9040_power_off(struct ld9040 *ctx)
213 {
214 	return regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
215 }
216 
217 static int ld9040_disable(struct drm_panel *panel)
218 {
219 	return 0;
220 }
221 
222 static int ld9040_unprepare(struct drm_panel *panel)
223 {
224 	struct ld9040 *ctx = panel_to_ld9040(panel);
225 
226 	msleep(120);
227 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_OFF);
228 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_ENTER_SLEEP_MODE);
229 	msleep(40);
230 
231 	ld9040_clear_error(ctx);
232 
233 	return ld9040_power_off(ctx);
234 }
235 
236 static int ld9040_prepare(struct drm_panel *panel)
237 {
238 	struct ld9040 *ctx = panel_to_ld9040(panel);
239 	int ret;
240 
241 	ret = ld9040_power_on(ctx);
242 	if (ret < 0)
243 		return ret;
244 
245 	ld9040_init(ctx);
246 
247 	ret = ld9040_clear_error(ctx);
248 
249 	if (ret < 0)
250 		ld9040_unprepare(panel);
251 
252 	return ret;
253 }
254 
255 static int ld9040_enable(struct drm_panel *panel)
256 {
257 	return 0;
258 }
259 
260 static int ld9040_get_modes(struct drm_panel *panel)
261 {
262 	struct drm_connector *connector = panel->connector;
263 	struct ld9040 *ctx = panel_to_ld9040(panel);
264 	struct drm_display_mode *mode;
265 
266 	mode = drm_mode_create(connector->dev);
267 	if (!mode) {
268 		DRM_ERROR("failed to create a new display mode\n");
269 		return 0;
270 	}
271 
272 	drm_display_mode_from_videomode(&ctx->vm, mode);
273 	mode->width_mm = ctx->width_mm;
274 	mode->height_mm = ctx->height_mm;
275 	connector->display_info.width_mm = mode->width_mm;
276 	connector->display_info.height_mm = mode->height_mm;
277 
278 	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
279 	drm_mode_probed_add(connector, mode);
280 
281 	return 1;
282 }
283 
284 static const struct drm_panel_funcs ld9040_drm_funcs = {
285 	.disable = ld9040_disable,
286 	.unprepare = ld9040_unprepare,
287 	.prepare = ld9040_prepare,
288 	.enable = ld9040_enable,
289 	.get_modes = ld9040_get_modes,
290 };
291 
292 static int ld9040_parse_dt(struct ld9040 *ctx)
293 {
294 	struct device *dev = ctx->dev;
295 	struct device_node *np = dev->of_node;
296 	int ret;
297 
298 	ret = of_get_videomode(np, &ctx->vm, 0);
299 	if (ret < 0)
300 		return ret;
301 
302 	of_property_read_u32(np, "power-on-delay", &ctx->power_on_delay);
303 	of_property_read_u32(np, "reset-delay", &ctx->reset_delay);
304 	of_property_read_u32(np, "panel-width-mm", &ctx->width_mm);
305 	of_property_read_u32(np, "panel-height-mm", &ctx->height_mm);
306 
307 	return 0;
308 }
309 
310 static int ld9040_probe(struct spi_device *spi)
311 {
312 	struct device *dev = &spi->dev;
313 	struct ld9040 *ctx;
314 	int ret;
315 
316 	ctx = devm_kzalloc(dev, sizeof(struct ld9040), GFP_KERNEL);
317 	if (!ctx)
318 		return -ENOMEM;
319 
320 	spi_set_drvdata(spi, ctx);
321 
322 	ctx->dev = dev;
323 	ctx->brightness = ARRAY_SIZE(ld9040_gammas) - 1;
324 
325 	ret = ld9040_parse_dt(ctx);
326 	if (ret < 0)
327 		return ret;
328 
329 	ctx->supplies[0].supply = "vdd3";
330 	ctx->supplies[1].supply = "vci";
331 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ctx->supplies),
332 				      ctx->supplies);
333 	if (ret < 0)
334 		return ret;
335 
336 	ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
337 	if (IS_ERR(ctx->reset_gpio)) {
338 		dev_err(dev, "cannot get reset-gpios %ld\n",
339 			PTR_ERR(ctx->reset_gpio));
340 		return PTR_ERR(ctx->reset_gpio);
341 	}
342 
343 	spi->bits_per_word = 9;
344 	ret = spi_setup(spi);
345 	if (ret < 0) {
346 		dev_err(dev, "spi setup failed.\n");
347 		return ret;
348 	}
349 
350 	drm_panel_init(&ctx->panel);
351 	ctx->panel.dev = dev;
352 	ctx->panel.funcs = &ld9040_drm_funcs;
353 
354 	return drm_panel_add(&ctx->panel);
355 }
356 
357 static int ld9040_remove(struct spi_device *spi)
358 {
359 	struct ld9040 *ctx = spi_get_drvdata(spi);
360 
361 	ld9040_power_off(ctx);
362 	drm_panel_remove(&ctx->panel);
363 
364 	return 0;
365 }
366 
367 static const struct of_device_id ld9040_of_match[] = {
368 	{ .compatible = "samsung,ld9040" },
369 	{ }
370 };
371 MODULE_DEVICE_TABLE(of, ld9040_of_match);
372 
373 static struct spi_driver ld9040_driver = {
374 	.probe = ld9040_probe,
375 	.remove = ld9040_remove,
376 	.driver = {
377 		.name = "panel-samsung-ld9040",
378 		.of_match_table = ld9040_of_match,
379 	},
380 };
381 module_spi_driver(ld9040_driver);
382 
383 MODULE_AUTHOR("Andrzej Hajda <a.hajda@samsung.com>");
384 MODULE_DESCRIPTION("ld9040 LCD Driver");
385 MODULE_LICENSE("GPL v2");
386