summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/panel/panel-widechips-ws2401.c
blob: 2591ff8f0d4e8b84b7283718bf05684e8d44d1f5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
// SPDX-License-Identifier: GPL-2.0
/*
 * Panel driver for the WideChips WS2401 480x800 DPI RGB panel, used in
 * the Samsung Mobile Display (SMD) LMS380KF01.
 * Found in the Samsung Galaxy Ace 2 GT-I8160 mobile phone.
 * Linus Walleij <linus.walleij@linaro.org>
 * Inspired by code and know-how in the vendor driver by Gareth Phillips.
 */
#include <drm/drm_mipi_dbi.h>
#include <drm/drm_modes.h>
#include <drm/drm_panel.h>

#include <linux/backlight.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/media-bus-format.h>
#include <linux/module.h>
#include <linux/regulator/consumer.h>
#include <linux/spi/spi.h>

#include <video/mipi_display.h>

#define WS2401_RESCTL			0xb8 /* Resolution select control */
#define WS2401_PSMPS			0xbd /* SMPS positive control */
#define WS2401_NSMPS			0xbe /* SMPS negative control */
#define WS2401_SMPS			0xbf
#define WS2401_BCMODE			0xc1 /* Backlight control mode */
#define WS2401_WRBLCTL			0xc3 /* Backlight control */
#define WS2401_WRDISBV			0xc4 /* Write manual brightness */
#define WS2401_WRCTRLD			0xc6 /* Write BL control */
#define WS2401_WRMIE			0xc7 /* Write MIE mode */
#define WS2401_READ_ID1			0xda /* Read panel ID 1 */
#define WS2401_READ_ID2			0xdb /* Read panel ID 2 */
#define WS2401_READ_ID3			0xdc /* Read panel ID 3 */
#define WS2401_GAMMA_R1			0xe7 /* Gamma red 1 */
#define WS2401_GAMMA_G1			0xe8 /* Gamma green 1 */
#define WS2401_GAMMA_B1			0xe9 /* Gamma blue 1 */
#define WS2401_GAMMA_R2			0xea /* Gamma red 2 */
#define WS2401_GAMMA_G2			0xeb /* Gamma green 2 */
#define WS2401_GAMMA_B2			0xec /* Gamma blue 2 */
#define WS2401_PASSWD1			0xf0 /* Password command for level 2 */
#define WS2401_DISCTL			0xf2 /* Display control */
#define WS2401_PWRCTL			0xf3 /* Power control */
#define WS2401_VCOMCTL			0xf4 /* VCOM control */
#define WS2401_SRCCTL			0xf5 /* Source control */
#define WS2401_PANELCTL			0xf6 /* Panel control */

static const u8 ws2401_dbi_read_commands[] = {
	WS2401_READ_ID1,
	WS2401_READ_ID2,
	WS2401_READ_ID3,
	0, /* sentinel */
};

/**
 * struct ws2401 - state container for a panel controlled by the WS2401
 * controller
 */
struct ws2401 {
	/** @dev: the container device */
	struct device *dev;
	/** @dbi: the DBI bus abstraction handle */
	struct mipi_dbi dbi;
	/** @panel: the DRM panel instance for this device */
	struct drm_panel panel;
	/** @width: the width of this panel in mm */
	u32 width;
	/** @height: the height of this panel in mm */
	u32 height;
	/** @reset: reset GPIO line */
	struct gpio_desc *reset;
	/** @regulators: VCCIO and VIO supply regulators */
	struct regulator_bulk_data regulators[2];
	/** @internal_bl: If using internal backlight */
	bool internal_bl;
};

static const struct drm_display_mode lms380kf01_480_800_mode = {
	/*
	 * The vendor driver states that the "SMD panel" has a clock
	 * frequency of 49920000 Hz / 2 = 24960000 Hz.
	 */
	.clock = 24960,
	.hdisplay = 480,
	.hsync_start = 480 + 8,
	.hsync_end = 480 + 8 + 10,
	.htotal = 480 + 8 + 10 + 8,
	.vdisplay = 800,
	.vsync_start = 800 + 8,
	.vsync_end = 800 + 8 + 2,
	.vtotal = 800 + 8 + 2 + 18,
	.width_mm = 50,
	.height_mm = 84,
	.flags = DRM_MODE_FLAG_NVSYNC | DRM_MODE_FLAG_NHSYNC,
};

static inline struct ws2401 *to_ws2401(struct drm_panel *panel)
{
	return container_of(panel, struct ws2401, panel);
}

static void ws2401_read_mtp_id(struct ws2401 *ws)
{
	struct mipi_dbi *dbi = &ws->dbi;
	u8 id1, id2, id3;
	int ret;

	ret = mipi_dbi_command_read(dbi, WS2401_READ_ID1, &id1);
	if (ret) {
		dev_err(ws->dev, "unable to read MTP ID 1\n");
		return;
	}
	ret = mipi_dbi_command_read(dbi, WS2401_READ_ID2, &id2);
	if (ret) {
		dev_err(ws->dev, "unable to read MTP ID 2\n");
		return;
	}
	ret = mipi_dbi_command_read(dbi, WS2401_READ_ID3, &id3);
	if (ret) {
		dev_err(ws->dev, "unable to read MTP ID 3\n");
		return;
	}
	dev_info(ws->dev, "MTP ID: %02x %02x %02x\n", id1, id2, id3);
}

static int ws2401_power_on(struct ws2401 *ws)
{
	struct mipi_dbi *dbi = &ws->dbi;
	int ret;

	/* Power up */
	ret = regulator_bulk_enable(ARRAY_SIZE(ws->regulators),
				    ws->regulators);
	if (ret) {
		dev_err(ws->dev, "failed to enable regulators: %d\n", ret);
		return ret;
	}
	msleep(10);

	/* Assert reset >=1 ms */
	gpiod_set_value_cansleep(ws->reset, 1);
	usleep_range(1000, 5000);
	/* De-assert reset */
	gpiod_set_value_cansleep(ws->reset, 0);
	/* Wait >= 10 ms */
	msleep(10);
	dev_dbg(ws->dev, "de-asserted RESET\n");

	/*
	 * Exit sleep mode and initialize display - some hammering is
	 * necessary.
	 */
	mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
	mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
	msleep(50);

	/* Magic to unlock level 2 control of the display */
	mipi_dbi_command(dbi, WS2401_PASSWD1, 0x5a, 0x5a);
	/* Configure resolution to 480RGBx800 */
	mipi_dbi_command(dbi, WS2401_RESCTL, 0x12);
	/* Set addressing mode Flip V(d0), Flip H(d1) RGB/BGR(d3) */
	mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, 0x01);
	/* Set pixel format: 24 bpp */
	mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT, 0x70);
	mipi_dbi_command(dbi, WS2401_SMPS, 0x00, 0x0f);
	mipi_dbi_command(dbi, WS2401_PSMPS, 0x06, 0x03, /* DDVDH: 4.6v */
			 0x7e, 0x03, 0x12, 0x37);
	mipi_dbi_command(dbi, WS2401_NSMPS, 0x06, 0x03, /* DDVDH: -4.6v */
			 0x7e, 0x02, 0x15, 0x37);
	mipi_dbi_command(dbi, WS2401_SMPS, 0x02, 0x0f);
	mipi_dbi_command(dbi, WS2401_PWRCTL, 0x10, 0xA9, 0x00, 0x01, 0x44,
			 0xb4,	/* VGH:16.1v, VGL:-13.8v */
			 0x50,	/* GREFP:4.2v (default) */
			 0x50,	/* GREFN:-4.2v (default) */
			 0x00,
			 0x44);	/* VOUTL:-10v (default) */
	mipi_dbi_command(dbi, WS2401_DISCTL, 0x01, 0x00, 0x00, 0x00, 0x14,
			 0x16);
	mipi_dbi_command(dbi, WS2401_VCOMCTL, 0x30, 0x53, 0x53);
	mipi_dbi_command(dbi, WS2401_SRCCTL, 0x03, 0x0C, 0x00, 0x00, 0x00,
			 0x01,	/* 2 dot inversion */
			 0x01, 0x06, 0x03);
	mipi_dbi_command(dbi, WS2401_PANELCTL, 0x14, 0x00, 0x80, 0x00);
	mipi_dbi_command(dbi, WS2401_WRMIE, 0x01);

	/* Set up gamma, probably these are P-gamma and N-gamma for each color */
	mipi_dbi_command(dbi, WS2401_GAMMA_R1, 0x00,
			 0x5b, 0x42, 0x41, 0x3f, 0x42, 0x3d, 0x38, 0x2e,
			 0x2b, 0x2a, 0x27, 0x22, 0x27, 0x0f, 0x00, 0x00);
	mipi_dbi_command(dbi, WS2401_GAMMA_R2, 0x00,
			 0x5b, 0x42, 0x41, 0x3f, 0x42, 0x3d, 0x38, 0x2e,
			 0x2b, 0x2a, 0x27, 0x22, 0x27, 0x0f, 0x00, 0x00);
	mipi_dbi_command(dbi, WS2401_GAMMA_G1, 0x00,
			 0x59, 0x40, 0x3f, 0x3e, 0x41, 0x3d, 0x39, 0x2f,
			 0x2c, 0x2b, 0x29, 0x25, 0x29, 0x19, 0x08, 0x00);
	mipi_dbi_command(dbi, WS2401_GAMMA_G2, 0x00,
			 0x59, 0x40, 0x3f, 0x3e, 0x41, 0x3d, 0x39, 0x2f,
			 0x2c, 0x2b, 0x29, 0x25, 0x29, 0x19, 0x08, 0x00);
	mipi_dbi_command(dbi, WS2401_GAMMA_B1, 0x00,
			 0x57, 0x3b, 0x3a, 0x3b, 0x3f, 0x3b, 0x38, 0x27,
			 0x38, 0x2a, 0x26, 0x22, 0x34, 0x0c, 0x09, 0x00);
	mipi_dbi_command(dbi, WS2401_GAMMA_B2, 0x00,
			 0x57, 0x3b, 0x3a, 0x3b, 0x3f, 0x3b, 0x38, 0x27,
			 0x38, 0x2a, 0x26, 0x22, 0x34, 0x0c, 0x09, 0x00);

	if (ws->internal_bl) {
		mipi_dbi_command(dbi, WS2401_WRCTRLD, 0x2c);
	} else {
		mipi_dbi_command(dbi, WS2401_WRCTRLD, 0x00);
		/*
		 * When not using internal backlight we do not need any further
		 * L2 accesses to the panel so we close the door on our way out.
		 * Otherwise we need to leave the L2 door open.
		 */
		mipi_dbi_command(dbi, WS2401_PASSWD1, 0xa5, 0xa5);
	}

	return 0;
}

static int ws2401_power_off(struct ws2401 *ws)
{
	/* Go into RESET and disable regulators */
	gpiod_set_value_cansleep(ws->reset, 1);
	return regulator_bulk_disable(ARRAY_SIZE(ws->regulators),
				      ws->regulators);
}

static int ws2401_unprepare(struct drm_panel *panel)
{
	struct ws2401 *ws = to_ws2401(panel);
	struct mipi_dbi *dbi = &ws->dbi;

	/* Make sure we disable backlight, if any */
	if (ws->internal_bl)
		mipi_dbi_command(dbi, WS2401_WRCTRLD, 0x00);
	mipi_dbi_command(dbi, MIPI_DCS_ENTER_SLEEP_MODE);
	msleep(120);
	return ws2401_power_off(to_ws2401(panel));
}

static int ws2401_disable(struct drm_panel *panel)
{
	struct ws2401 *ws = to_ws2401(panel);
	struct mipi_dbi *dbi = &ws->dbi;

	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_OFF);
	msleep(25);

	return 0;
}

static int ws2401_prepare(struct drm_panel *panel)
{
	return ws2401_power_on(to_ws2401(panel));
}

static int ws2401_enable(struct drm_panel *panel)
{
	struct ws2401 *ws = to_ws2401(panel);
	struct mipi_dbi *dbi = &ws->dbi;

	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);

	return 0;
}

/**
 * ws2401_get_modes() - return the mode
 * @panel: the panel to get the mode for
 * @connector: reference to the central DRM connector control structure
 */
static int ws2401_get_modes(struct drm_panel *panel,
			    struct drm_connector *connector)
{
	struct ws2401 *ws = to_ws2401(panel);
	struct drm_display_mode *mode;
	static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;

	/*
	 * We just support the LMS380KF01 so far, if we implement more panels
	 * this mode, the following connector display_info settings and
	 * probably the custom DCS sequences needs to selected based on what
	 * the target panel needs.
	 */
	mode = drm_mode_duplicate(connector->dev, &lms380kf01_480_800_mode);
	if (!mode) {
		dev_err(ws->dev, "failed to add mode\n");
		return -ENOMEM;
	}

	connector->display_info.bpc = 8;
	connector->display_info.width_mm = mode->width_mm;
	connector->display_info.height_mm = mode->height_mm;
	connector->display_info.bus_flags =
		DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE;
	drm_display_info_set_bus_formats(&connector->display_info,
					 &bus_format, 1);

	drm_mode_set_name(mode);
	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;

	drm_mode_probed_add(connector, mode);

	return 1;
}

static const struct drm_panel_funcs ws2401_drm_funcs = {
	.disable = ws2401_disable,
	.unprepare = ws2401_unprepare,
	.prepare = ws2401_prepare,
	.enable = ws2401_enable,
	.get_modes = ws2401_get_modes,
};

static int ws2401_set_brightness(struct backlight_device *bl)
{
	struct ws2401 *ws = bl_get_data(bl);
	struct mipi_dbi *dbi = &ws->dbi;
	u8 brightness = backlight_get_brightness(bl);

	if (backlight_is_blank(bl)) {
		mipi_dbi_command(dbi, WS2401_WRCTRLD, 0x00);
	} else {
		mipi_dbi_command(dbi, WS2401_WRCTRLD, 0x2c);
		mipi_dbi_command(dbi, WS2401_WRDISBV, brightness);
	}

	return 0;
}

static const struct backlight_ops ws2401_bl_ops = {
	.update_status = ws2401_set_brightness,
};

static const struct backlight_properties ws2401_bl_props = {
	.type = BACKLIGHT_PLATFORM,
	.brightness = 120,
	.max_brightness = U8_MAX,
};

static int ws2401_probe(struct spi_device *spi)
{
	struct device *dev = &spi->dev;
	struct ws2401 *ws;
	int ret;

	ws = devm_kzalloc(dev, sizeof(*ws), GFP_KERNEL);
	if (!ws)
		return -ENOMEM;
	ws->dev = dev;

	/*
	 * VCI   is the analog voltage supply
	 * VCCIO is the digital I/O voltage supply
	 */
	ws->regulators[0].supply = "vci";
	ws->regulators[1].supply = "vccio";
	ret = devm_regulator_bulk_get(dev,
				      ARRAY_SIZE(ws->regulators),
				      ws->regulators);
	if (ret)
		return dev_err_probe(dev, ret, "failed to get regulators\n");

	ws->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
	if (IS_ERR(ws->reset)) {
		ret = PTR_ERR(ws->reset);
		return dev_err_probe(dev, ret, "no RESET GPIO\n");
	}

	ret = mipi_dbi_spi_init(spi, &ws->dbi, NULL);
	if (ret)
		return dev_err_probe(dev, ret, "MIPI DBI init failed\n");
	ws->dbi.read_commands = ws2401_dbi_read_commands;

	ws2401_power_on(ws);
	ws2401_read_mtp_id(ws);
	ws2401_power_off(ws);

	drm_panel_init(&ws->panel, dev, &ws2401_drm_funcs,
		       DRM_MODE_CONNECTOR_DPI);

	ret = drm_panel_of_backlight(&ws->panel);
	if (ret)
		return dev_err_probe(dev, ret,
				"failed to get external backlight device\n");

	if (!ws->panel.backlight) {
		dev_dbg(dev, "no external backlight, using internal backlight\n");
		ws->panel.backlight =
			devm_backlight_device_register(dev, "ws2401", dev, ws,
				&ws2401_bl_ops, &ws2401_bl_props);
		if (IS_ERR(ws->panel.backlight))
			return dev_err_probe(dev, PTR_ERR(ws->panel.backlight),
				"failed to register backlight device\n");
	} else {
		dev_dbg(dev, "using external backlight\n");
	}

	spi_set_drvdata(spi, ws);

	drm_panel_add(&ws->panel);
	dev_dbg(dev, "added panel\n");

	return 0;
}

static void ws2401_remove(struct spi_device *spi)
{
	struct ws2401 *ws = spi_get_drvdata(spi);

	drm_panel_remove(&ws->panel);
}

/*
 * Samsung LMS380KF01 is the one instance of this display controller that we
 * know about, but if more are found, the controller can be parameterized
 * here and used for other configurations.
 */
static const struct of_device_id ws2401_match[] = {
	{ .compatible = "samsung,lms380kf01", },
	{},
};
MODULE_DEVICE_TABLE(of, ws2401_match);

static const struct spi_device_id ws2401_ids[] = {
	{ "lms380kf01" },
	{ },
};
MODULE_DEVICE_TABLE(spi, ws2401_ids);

static struct spi_driver ws2401_driver = {
	.probe		= ws2401_probe,
	.remove		= ws2401_remove,
	.id_table	= ws2401_ids,
	.driver		= {
		.name	= "ws2401-panel",
		.of_match_table = ws2401_match,
	},
};
module_spi_driver(ws2401_driver);

MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
MODULE_DESCRIPTION("Samsung WS2401 panel driver");
MODULE_LICENSE("GPL v2");