1 /*
2  * ld9040 AMOLED LCD drm_panel driver.
3  *
4  * Copyright (c) 2014 Samsung Electronics Co., Ltd
5  * Derived from drivers/video/backlight/ld9040.c
6  *
7  * Andrzej Hajda <a.hajda@samsung.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12 */
13 
14 #include <drm/drmP.h>
15 #include <drm/drm_panel.h>
16 
17 #include <linux/gpio/consumer.h>
18 #include <linux/regulator/consumer.h>
19 #include <linux/spi/spi.h>
20 
21 #include <video/mipi_display.h>
22 #include <video/of_videomode.h>
23 #include <video/videomode.h>
24 
25 /* Manufacturer Command Set */
26 #define MCS_MANPWR		0xb0
27 #define MCS_ELVSS_ON		0xb1
28 #define MCS_USER_SETTING	0xf0
29 #define MCS_DISPCTL		0xf2
30 #define MCS_POWER_CTRL		0xf4
31 #define MCS_GTCON		0xf7
32 #define MCS_PANEL_CONDITION	0xf8
33 #define MCS_GAMMA_SET1		0xf9
34 #define MCS_GAMMA_CTRL		0xfb
35 
36 /* array of gamma tables for gamma value 2.2 */
37 static u8 const ld9040_gammas[25][22] = {
38 	{ 0xf9, 0x00, 0x13, 0xb2, 0xba, 0xd2, 0x00, 0x30, 0x00, 0xaf, 0xc0,
39 	  0xb8, 0xcd, 0x00, 0x3d, 0x00, 0xa8, 0xb8, 0xb7, 0xcd, 0x00, 0x44 },
40 	{ 0xf9, 0x00, 0x13, 0xb9, 0xb9, 0xd0, 0x00, 0x3c, 0x00, 0xaf, 0xbf,
41 	  0xb6, 0xcb, 0x00, 0x4b, 0x00, 0xa8, 0xb9, 0xb5, 0xcc, 0x00, 0x52 },
42 	{ 0xf9, 0x00, 0x13, 0xba, 0xb9, 0xcd, 0x00, 0x41, 0x00, 0xb0, 0xbe,
43 	  0xb5, 0xc9, 0x00, 0x51, 0x00, 0xa9, 0xb9, 0xb5, 0xca, 0x00, 0x57 },
44 	{ 0xf9, 0x00, 0x13, 0xb9, 0xb8, 0xcd, 0x00, 0x46, 0x00, 0xb1, 0xbc,
45 	  0xb5, 0xc8, 0x00, 0x56, 0x00, 0xaa, 0xb8, 0xb4, 0xc9, 0x00, 0x5d },
46 	{ 0xf9, 0x00, 0x13, 0xba, 0xb8, 0xcb, 0x00, 0x4b, 0x00, 0xb3, 0xbc,
47 	  0xb4, 0xc7, 0x00, 0x5c, 0x00, 0xac, 0xb8, 0xb4, 0xc8, 0x00, 0x62 },
48 	{ 0xf9, 0x00, 0x13, 0xbb, 0xb7, 0xca, 0x00, 0x4f, 0x00, 0xb4, 0xbb,
49 	  0xb3, 0xc7, 0x00, 0x60, 0x00, 0xad, 0xb8, 0xb4, 0xc7, 0x00, 0x67 },
50 	{ 0xf9, 0x00, 0x47, 0xba, 0xb6, 0xca, 0x00, 0x53, 0x00, 0xb5, 0xbb,
51 	  0xb3, 0xc6, 0x00, 0x65, 0x00, 0xae, 0xb8, 0xb3, 0xc7, 0x00, 0x6c },
52 	{ 0xf9, 0x00, 0x71, 0xbb, 0xb5, 0xc8, 0x00, 0x57, 0x00, 0xb5, 0xbb,
53 	  0xb0, 0xc5, 0x00, 0x6a, 0x00, 0xae, 0xb9, 0xb1, 0xc6, 0x00, 0x70 },
54 	{ 0xf9, 0x00, 0x7b, 0xbb, 0xb4, 0xc8, 0x00, 0x5b, 0x00, 0xb5, 0xba,
55 	  0xb1, 0xc4, 0x00, 0x6e, 0x00, 0xae, 0xb9, 0xb0, 0xc5, 0x00, 0x75 },
56 	{ 0xf9, 0x00, 0x82, 0xba, 0xb4, 0xc7, 0x00, 0x5f, 0x00, 0xb5, 0xba,
57 	  0xb0, 0xc3, 0x00, 0x72, 0x00, 0xae, 0xb8, 0xb0, 0xc3, 0x00, 0x7a },
58 	{ 0xf9, 0x00, 0x89, 0xba, 0xb3, 0xc8, 0x00, 0x62, 0x00, 0xb6, 0xba,
59 	  0xaf, 0xc3, 0x00, 0x76, 0x00, 0xaf, 0xb7, 0xae, 0xc4, 0x00, 0x7e },
60 	{ 0xf9, 0x00, 0x8b, 0xb9, 0xb3, 0xc7, 0x00, 0x65, 0x00, 0xb7, 0xb8,
61 	  0xaf, 0xc3, 0x00, 0x7a, 0x00, 0x80, 0xb6, 0xae, 0xc4, 0x00, 0x81 },
62 	{ 0xf9, 0x00, 0x93, 0xba, 0xb3, 0xc5, 0x00, 0x69, 0x00, 0xb8, 0xb9,
63 	  0xae, 0xc1, 0x00, 0x7f, 0x00, 0xb0, 0xb6, 0xae, 0xc3, 0x00, 0x85 },
64 	{ 0xf9, 0x00, 0x97, 0xba, 0xb2, 0xc5, 0x00, 0x6c, 0x00, 0xb8, 0xb8,
65 	  0xae, 0xc1, 0x00, 0x82, 0x00, 0xb0, 0xb6, 0xae, 0xc2, 0x00, 0x89 },
66 	{ 0xf9, 0x00, 0x9a, 0xba, 0xb1, 0xc4, 0x00, 0x6f, 0x00, 0xb8, 0xb8,
67 	  0xad, 0xc0, 0x00, 0x86, 0x00, 0xb0, 0xb7, 0xad, 0xc0, 0x00, 0x8d },
68 	{ 0xf9, 0x00, 0x9c, 0xb9, 0xb0, 0xc4, 0x00, 0x72, 0x00, 0xb8, 0xb8,
69 	  0xac, 0xbf, 0x00, 0x8a, 0x00, 0xb0, 0xb6, 0xac, 0xc0, 0x00, 0x91 },
70 	{ 0xf9, 0x00, 0x9e, 0xba, 0xb0, 0xc2, 0x00, 0x75, 0x00, 0xb9, 0xb8,
71 	  0xab, 0xbe, 0x00, 0x8e, 0x00, 0xb0, 0xb6, 0xac, 0xbf, 0x00, 0x94 },
72 	{ 0xf9, 0x00, 0xa0, 0xb9, 0xaf, 0xc3, 0x00, 0x77, 0x00, 0xb9, 0xb7,
73 	  0xab, 0xbe, 0x00, 0x90, 0x00, 0xb0, 0xb6, 0xab, 0xbf, 0x00, 0x97 },
74 	{ 0xf9, 0x00, 0xa2, 0xb9, 0xaf, 0xc2, 0x00, 0x7a, 0x00, 0xb9, 0xb7,
75 	  0xaa, 0xbd, 0x00, 0x94, 0x00, 0xb0, 0xb5, 0xab, 0xbf, 0x00, 0x9a },
76 	{ 0xf9, 0x00, 0xa4, 0xb9, 0xaf, 0xc1, 0x00, 0x7d, 0x00, 0xb9, 0xb6,
77 	  0xaa, 0xbb, 0x00, 0x97, 0x00, 0xb1, 0xb5, 0xaa, 0xbf, 0x00, 0x9d },
78 	{ 0xf9, 0x00, 0xa4, 0xb8, 0xb0, 0xbf, 0x00, 0x80, 0x00, 0xb8, 0xb6,
79 	  0xaa, 0xbc, 0x00, 0x9a, 0x00, 0xb0, 0xb5, 0xab, 0xbd, 0x00, 0xa0 },
80 	{ 0xf9, 0x00, 0xa8, 0xb8, 0xae, 0xbe, 0x00, 0x84, 0x00, 0xb9, 0xb7,
81 	  0xa8, 0xbc, 0x00, 0x9d, 0x00, 0xb2, 0xb5, 0xaa, 0xbc, 0x00, 0xa4 },
82 	{ 0xf9, 0x00, 0xa9, 0xb6, 0xad, 0xbf, 0x00, 0x86, 0x00, 0xb8, 0xb5,
83 	  0xa8, 0xbc, 0x00, 0xa0, 0x00, 0xb3, 0xb3, 0xa9, 0xbc, 0x00, 0xa7 },
84 	{ 0xf9, 0x00, 0xa9, 0xb7, 0xae, 0xbd, 0x00, 0x89, 0x00, 0xb7, 0xb6,
85 	  0xa8, 0xba, 0x00, 0xa4, 0x00, 0xb1, 0xb4, 0xaa, 0xbb, 0x00, 0xaa },
86 	{ 0xf9, 0x00, 0xa7, 0xb4, 0xae, 0xbf, 0x00, 0x91, 0x00, 0xb2, 0xb4,
87 	  0xaa, 0xbb, 0x00, 0xac, 0x00, 0xb3, 0xb1, 0xaa, 0xbc, 0x00, 0xb3 },
88 };
89 
90 struct ld9040 {
91 	struct device *dev;
92 	struct drm_panel panel;
93 
94 	struct regulator_bulk_data supplies[2];
95 	struct gpio_desc *reset_gpio;
96 	u32 power_on_delay;
97 	u32 reset_delay;
98 	struct videomode vm;
99 	u32 width_mm;
100 	u32 height_mm;
101 
102 	int brightness;
103 
104 	/* This field is tested by functions directly accessing bus before
105 	 * transfer, transfer is skipped if it is set. In case of transfer
106 	 * failure or unexpected response the field is set to error value.
107 	 * Such construct allows to eliminate many checks in higher level
108 	 * functions.
109 	 */
110 	int error;
111 };
112 
113 static inline struct ld9040 *panel_to_ld9040(struct drm_panel *panel)
114 {
115 	return container_of(panel, struct ld9040, panel);
116 }
117 
118 static int ld9040_clear_error(struct ld9040 *ctx)
119 {
120 	int ret = ctx->error;
121 
122 	ctx->error = 0;
123 	return ret;
124 }
125 
126 static int ld9040_spi_write_word(struct ld9040 *ctx, u16 data)
127 {
128 	struct spi_device *spi = to_spi_device(ctx->dev);
129 	struct spi_transfer xfer = {
130 		.len		= 2,
131 		.tx_buf		= &data,
132 	};
133 	struct spi_message msg;
134 
135 	spi_message_init(&msg);
136 	spi_message_add_tail(&xfer, &msg);
137 
138 	return spi_sync(spi, &msg);
139 }
140 
141 static void ld9040_dcs_write(struct ld9040 *ctx, const u8 *data, size_t len)
142 {
143 	int ret = 0;
144 
145 	if (ctx->error < 0 || len == 0)
146 		return;
147 
148 	dev_dbg(ctx->dev, "writing dcs seq: %*ph\n", (int)len, data);
149 	ret = ld9040_spi_write_word(ctx, *data);
150 
151 	while (!ret && --len) {
152 		++data;
153 		ret = ld9040_spi_write_word(ctx, *data | 0x100);
154 	}
155 
156 	if (ret) {
157 		dev_err(ctx->dev, "error %d writing dcs seq: %*ph\n", ret,
158 			(int)len, data);
159 		ctx->error = ret;
160 	}
161 
162 	usleep_range(300, 310);
163 }
164 
165 #define ld9040_dcs_write_seq_static(ctx, seq...) \
166 ({\
167 	static const u8 d[] = { seq };\
168 	ld9040_dcs_write(ctx, d, ARRAY_SIZE(d));\
169 })
170 
171 static void ld9040_brightness_set(struct ld9040 *ctx)
172 {
173 	ld9040_dcs_write(ctx, ld9040_gammas[ctx->brightness],
174 			 ARRAY_SIZE(ld9040_gammas[ctx->brightness]));
175 
176 	ld9040_dcs_write_seq_static(ctx, MCS_GAMMA_CTRL, 0x02, 0x5a);
177 }
178 
179 static void ld9040_init(struct ld9040 *ctx)
180 {
181 	ld9040_dcs_write_seq_static(ctx, MCS_USER_SETTING, 0x5a, 0x5a);
182 	ld9040_dcs_write_seq_static(ctx, MCS_PANEL_CONDITION,
183 		0x05, 0x65, 0x96, 0x71, 0x7d, 0x19, 0x3b, 0x0d,
184 		0x19, 0x7e, 0x0d, 0xe2, 0x00, 0x00, 0x7e, 0x7d,
185 		0x07, 0x07, 0x20, 0x20, 0x20, 0x02, 0x02);
186 	ld9040_dcs_write_seq_static(ctx, MCS_DISPCTL,
187 		0x02, 0x08, 0x08, 0x10, 0x10);
188 	ld9040_dcs_write_seq_static(ctx, MCS_MANPWR, 0x04);
189 	ld9040_dcs_write_seq_static(ctx, MCS_POWER_CTRL,
190 		0x0a, 0x87, 0x25, 0x6a, 0x44, 0x02, 0x88);
191 	ld9040_dcs_write_seq_static(ctx, MCS_ELVSS_ON, 0x0d, 0x00, 0x16);
192 	ld9040_dcs_write_seq_static(ctx, MCS_GTCON, 0x09, 0x00, 0x00);
193 	ld9040_brightness_set(ctx);
194 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_EXIT_SLEEP_MODE);
195 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_ON);
196 }
197 
198 static int ld9040_power_on(struct ld9040 *ctx)
199 {
200 	int ret;
201 
202 	ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
203 	if (ret < 0)
204 		return ret;
205 
206 	msleep(ctx->power_on_delay);
207 	gpiod_set_value(ctx->reset_gpio, 0);
208 	msleep(ctx->reset_delay);
209 	gpiod_set_value(ctx->reset_gpio, 1);
210 	msleep(ctx->reset_delay);
211 
212 	return 0;
213 }
214 
215 static int ld9040_power_off(struct ld9040 *ctx)
216 {
217 	return regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
218 }
219 
220 static int ld9040_disable(struct drm_panel *panel)
221 {
222 	return 0;
223 }
224 
225 static int ld9040_unprepare(struct drm_panel *panel)
226 {
227 	struct ld9040 *ctx = panel_to_ld9040(panel);
228 
229 	msleep(120);
230 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_OFF);
231 	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_ENTER_SLEEP_MODE);
232 	msleep(40);
233 
234 	ld9040_clear_error(ctx);
235 
236 	return ld9040_power_off(ctx);
237 }
238 
239 static int ld9040_prepare(struct drm_panel *panel)
240 {
241 	struct ld9040 *ctx = panel_to_ld9040(panel);
242 	int ret;
243 
244 	ret = ld9040_power_on(ctx);
245 	if (ret < 0)
246 		return ret;
247 
248 	ld9040_init(ctx);
249 
250 	ret = ld9040_clear_error(ctx);
251 
252 	if (ret < 0)
253 		ld9040_unprepare(panel);
254 
255 	return ret;
256 }
257 
258 static int ld9040_enable(struct drm_panel *panel)
259 {
260 	return 0;
261 }
262 
263 static int ld9040_get_modes(struct drm_panel *panel)
264 {
265 	struct drm_connector *connector = panel->connector;
266 	struct ld9040 *ctx = panel_to_ld9040(panel);
267 	struct drm_display_mode *mode;
268 
269 	mode = drm_mode_create(connector->dev);
270 	if (!mode) {
271 		DRM_ERROR("failed to create a new display mode\n");
272 		return 0;
273 	}
274 
275 	drm_display_mode_from_videomode(&ctx->vm, mode);
276 	mode->width_mm = ctx->width_mm;
277 	mode->height_mm = ctx->height_mm;
278 	connector->display_info.width_mm = mode->width_mm;
279 	connector->display_info.height_mm = mode->height_mm;
280 
281 	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
282 	drm_mode_probed_add(connector, mode);
283 
284 	return 1;
285 }
286 
287 static const struct drm_panel_funcs ld9040_drm_funcs = {
288 	.disable = ld9040_disable,
289 	.unprepare = ld9040_unprepare,
290 	.prepare = ld9040_prepare,
291 	.enable = ld9040_enable,
292 	.get_modes = ld9040_get_modes,
293 };
294 
295 static int ld9040_parse_dt(struct ld9040 *ctx)
296 {
297 	struct device *dev = ctx->dev;
298 	struct device_node *np = dev->of_node;
299 	int ret;
300 
301 	ret = of_get_videomode(np, &ctx->vm, 0);
302 	if (ret < 0)
303 		return ret;
304 
305 	of_property_read_u32(np, "power-on-delay", &ctx->power_on_delay);
306 	of_property_read_u32(np, "reset-delay", &ctx->reset_delay);
307 	of_property_read_u32(np, "panel-width-mm", &ctx->width_mm);
308 	of_property_read_u32(np, "panel-height-mm", &ctx->height_mm);
309 
310 	return 0;
311 }
312 
313 static int ld9040_probe(struct spi_device *spi)
314 {
315 	struct device *dev = &spi->dev;
316 	struct ld9040 *ctx;
317 	int ret;
318 
319 	ctx = devm_kzalloc(dev, sizeof(struct ld9040), GFP_KERNEL);
320 	if (!ctx)
321 		return -ENOMEM;
322 
323 	spi_set_drvdata(spi, ctx);
324 
325 	ctx->dev = dev;
326 	ctx->brightness = ARRAY_SIZE(ld9040_gammas) - 1;
327 
328 	ret = ld9040_parse_dt(ctx);
329 	if (ret < 0)
330 		return ret;
331 
332 	ctx->supplies[0].supply = "vdd3";
333 	ctx->supplies[1].supply = "vci";
334 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ctx->supplies),
335 				      ctx->supplies);
336 	if (ret < 0)
337 		return ret;
338 
339 	ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
340 	if (IS_ERR(ctx->reset_gpio)) {
341 		dev_err(dev, "cannot get reset-gpios %ld\n",
342 			PTR_ERR(ctx->reset_gpio));
343 		return PTR_ERR(ctx->reset_gpio);
344 	}
345 
346 	spi->bits_per_word = 9;
347 	ret = spi_setup(spi);
348 	if (ret < 0) {
349 		dev_err(dev, "spi setup failed.\n");
350 		return ret;
351 	}
352 
353 	drm_panel_init(&ctx->panel);
354 	ctx->panel.dev = dev;
355 	ctx->panel.funcs = &ld9040_drm_funcs;
356 
357 	return drm_panel_add(&ctx->panel);
358 }
359 
360 static int ld9040_remove(struct spi_device *spi)
361 {
362 	struct ld9040 *ctx = spi_get_drvdata(spi);
363 
364 	ld9040_power_off(ctx);
365 	drm_panel_remove(&ctx->panel);
366 
367 	return 0;
368 }
369 
370 static const struct of_device_id ld9040_of_match[] = {
371 	{ .compatible = "samsung,ld9040" },
372 	{ }
373 };
374 MODULE_DEVICE_TABLE(of, ld9040_of_match);
375 
376 static struct spi_driver ld9040_driver = {
377 	.probe = ld9040_probe,
378 	.remove = ld9040_remove,
379 	.driver = {
380 		.name = "panel-samsung-ld9040",
381 		.of_match_table = ld9040_of_match,
382 	},
383 };
384 module_spi_driver(ld9040_driver);
385 
386 MODULE_AUTHOR("Andrzej Hajda <a.hajda@samsung.com>");
387 MODULE_DESCRIPTION("ld9040 LCD Driver");
388 MODULE_LICENSE("GPL v2");
389