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 */
37static 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
90struct 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
113static inline struct ld9040 *panel_to_ld9040(struct drm_panel *panel)
114{
115	return container_of(panel, struct ld9040, panel);
116}
117
118static int ld9040_clear_error(struct ld9040 *ctx)
119{
120	int ret = ctx->error;
121
122	ctx->error = 0;
123	return ret;
124}
125
126static 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
141static 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
171static 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
179static 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
198static 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
215static int ld9040_power_off(struct ld9040 *ctx)
216{
217	return regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
218}
219
220static int ld9040_disable(struct drm_panel *panel)
221{
222	return 0;
223}
224
225static 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
239static 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
258static int ld9040_enable(struct drm_panel *panel)
259{
260	return 0;
261}
262
263static 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
287static 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
295static 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
313static 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
360static 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
370static const struct of_device_id ld9040_of_match[] = {
371	{ .compatible = "samsung,ld9040" },
372	{ }
373};
374MODULE_DEVICE_TABLE(of, ld9040_of_match);
375
376static 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};
384module_spi_driver(ld9040_driver);
385
386MODULE_AUTHOR("Andrzej Hajda <a.hajda@samsung.com>");
387MODULE_DESCRIPTION("ld9040 LCD Driver");
388MODULE_LICENSE("GPL v2");
389