xref: /linux/drivers/gpu/drm/panel/panel-ilitek-ili9322.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Ilitek ILI9322 TFT LCD drm_panel driver.
4  *
5  * This panel can be configured to support:
6  * - 8-bit serial RGB interface
7  * - 24-bit parallel RGB interface
8  * - 8-bit ITU-R BT.601 interface
9  * - 8-bit ITU-R BT.656 interface
10  * - Up to 320RGBx240 dots resolution TFT LCD displays
11  * - Scaling, brightness and contrast
12  *
13  * The scaling means that the display accepts a 640x480 or 720x480
14  * input and rescales it to fit to the 320x240 display. So what we
15  * present to the system is something else than what comes out on the
16  * actual display.
17  *
18  * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
19  * Derived from drivers/drm/gpu/panel/panel-samsung-ld9040.c
20  */
21 
22 #include <linux/bitops.h>
23 #include <linux/gpio/consumer.h>
24 #include <linux/module.h>
25 #include <linux/of.h>
26 #include <linux/platform_device.h>
27 #include <linux/regmap.h>
28 #include <linux/regulator/consumer.h>
29 #include <linux/spi/spi.h>
30 
31 #include <video/mipi_display.h>
32 #include <video/of_videomode.h>
33 #include <video/videomode.h>
34 
35 #include <drm/drm_modes.h>
36 #include <drm/drm_panel.h>
37 
38 #define ILI9322_CHIP_ID			0x00
39 #define ILI9322_CHIP_ID_MAGIC		0x96
40 
41 /*
42  * Voltage on the communication interface, from 0.7 (0x00)
43  * to 1.32 (0x1f) times the VREG1OUT voltage in 2% increments.
44  * 1.00 (0x0f) is the default.
45  */
46 #define ILI9322_VCOM_AMP		0x01
47 
48 /*
49  * High voltage on the communication signals, from 0.37 (0x00) to
50  * 1.0 (0x3f) times the VREGOUT1 voltage in 1% increments.
51  * 0.83 (0x2e) is the default.
52  */
53 #define ILI9322_VCOM_HIGH		0x02
54 
55 /*
56  * VREG1 voltage regulator from 3.6V (0x00) to 6.0V (0x18) in 0.1V
57  * increments. 5.4V (0x12) is the default. This is the reference
58  * voltage for the VCOM levels and the greyscale level.
59  */
60 #define ILI9322_VREG1_VOLTAGE		0x03
61 
62 /* Describes the incoming signal */
63 #define ILI9322_ENTRY			0x06
64 /* 0 = right-to-left, 1 = left-to-right (default), horizontal flip */
65 #define ILI9322_ENTRY_HDIR		BIT(0)
66 /* 0 = down-to-up, 1 = up-to-down (default), vertical flip  */
67 #define ILI9322_ENTRY_VDIR		BIT(1)
68 /* NTSC, PAL or autodetect */
69 #define ILI9322_ENTRY_NTSC		(0 << 2)
70 #define ILI9322_ENTRY_PAL		(1 << 2)
71 #define ILI9322_ENTRY_AUTODETECT	(3 << 2)
72 /* Input format */
73 #define ILI9322_ENTRY_SERIAL_RGB_THROUGH (0 << 4)
74 #define ILI9322_ENTRY_SERIAL_RGB_ALIGNED (1 << 4)
75 #define ILI9322_ENTRY_SERIAL_RGB_DUMMY_320X240 (2 << 4)
76 #define ILI9322_ENTRY_SERIAL_RGB_DUMMY_360X240 (3 << 4)
77 #define ILI9322_ENTRY_DISABLE_1		(4 << 4)
78 #define ILI9322_ENTRY_PARALLEL_RGB_THROUGH (5 << 4)
79 #define ILI9322_ENTRY_PARALLEL_RGB_ALIGNED (6 << 4)
80 #define ILI9322_ENTRY_YUV_640Y_320CBCR_25_54_MHZ (7 << 4)
81 #define ILI9322_ENTRY_YUV_720Y_360CBCR_27_MHZ (8 << 4)
82 #define ILI9322_ENTRY_DISABLE_2		(9 << 4)
83 #define ILI9322_ENTRY_ITU_R_BT_656_720X360 (10 << 4)
84 #define ILI9322_ENTRY_ITU_R_BT_656_640X320 (11 << 4)
85 
86 /* Power control */
87 #define ILI9322_POW_CTRL		0x07
88 #define ILI9322_POW_CTRL_STB		BIT(0) /* 0 = standby, 1 = normal */
89 #define ILI9322_POW_CTRL_VGL		BIT(1) /* 0 = off, 1 = on  */
90 #define ILI9322_POW_CTRL_VGH		BIT(2) /* 0 = off, 1 = on  */
91 #define ILI9322_POW_CTRL_DDVDH		BIT(3) /* 0 = off, 1 = on  */
92 #define ILI9322_POW_CTRL_VCOM		BIT(4) /* 0 = off, 1 = on  */
93 #define ILI9322_POW_CTRL_VCL		BIT(5) /* 0 = off, 1 = on  */
94 #define ILI9322_POW_CTRL_AUTO		BIT(6) /* 0 = interactive, 1 = auto */
95 #define ILI9322_POW_CTRL_STANDBY	(ILI9322_POW_CTRL_VGL | \
96 					 ILI9322_POW_CTRL_VGH | \
97 					 ILI9322_POW_CTRL_DDVDH | \
98 					 ILI9322_POW_CTRL_VCL | \
99 					 ILI9322_POW_CTRL_AUTO | \
100 					 BIT(7))
101 #define ILI9322_POW_CTRL_DEFAULT	(ILI9322_POW_CTRL_STANDBY | \
102 					 ILI9322_POW_CTRL_STB)
103 
104 /* Vertical back porch bits 0..5 */
105 #define ILI9322_VBP			0x08
106 
107 /* Horizontal back porch, 8 bits */
108 #define ILI9322_HBP			0x09
109 
110 /*
111  * Polarity settings:
112  * 1 = positive polarity
113  * 0 = negative polarity
114  */
115 #define ILI9322_POL			0x0a
116 #define ILI9322_POL_DCLK		BIT(0) /* 1 default */
117 #define ILI9322_POL_HSYNC		BIT(1) /* 0 default */
118 #define ILI9322_POL_VSYNC		BIT(2) /* 0 default */
119 #define ILI9322_POL_DE			BIT(3) /* 1 default */
120 /*
121  * 0 means YCBCR are ordered Cb0,Y0,Cr0,Y1,Cb2,Y2,Cr2,Y3 (default)
122  *   in RGB mode this means RGB comes in RGBRGB
123  * 1 means YCBCR are ordered Cr0,Y0,Cb0,Y1,Cr2,Y2,Cb2,Y3
124  *   in RGB mode this means RGB comes in BGRBGR
125  */
126 #define ILI9322_POL_YCBCR_MODE		BIT(4)
127 /* Formula A for YCbCR->RGB = 0, Formula B = 1 */
128 #define ILI9322_POL_FORMULA		BIT(5)
129 /* Reverse polarity: 0 = 0..255, 1 = 255..0 */
130 #define ILI9322_POL_REV			BIT(6)
131 
132 #define ILI9322_IF_CTRL			0x0b
133 #define ILI9322_IF_CTRL_HSYNC_VSYNC	0x00
134 #define ILI9322_IF_CTRL_HSYNC_VSYNC_DE	BIT(2)
135 #define ILI9322_IF_CTRL_DE_ONLY		BIT(3)
136 #define ILI9322_IF_CTRL_SYNC_DISABLED	(BIT(2) | BIT(3))
137 #define ILI9322_IF_CTRL_LINE_INVERSION	BIT(0) /* Not set means frame inv */
138 
139 #define ILI9322_GLOBAL_RESET		0x04
140 #define ILI9322_GLOBAL_RESET_ASSERT	0x00 /* bit 0 = 0 -> reset */
141 
142 /*
143  * 4+4 bits of negative and positive gamma correction
144  * Upper nybble, bits 4-7 are negative gamma
145  * Lower nybble, bits 0-3 are positive gamma
146  */
147 #define ILI9322_GAMMA_1			0x10
148 #define ILI9322_GAMMA_2			0x11
149 #define ILI9322_GAMMA_3			0x12
150 #define ILI9322_GAMMA_4			0x13
151 #define ILI9322_GAMMA_5			0x14
152 #define ILI9322_GAMMA_6			0x15
153 #define ILI9322_GAMMA_7			0x16
154 #define ILI9322_GAMMA_8			0x17
155 
156 /*
157  * enum ili9322_input - the format of the incoming signal to the panel
158  *
159  * The panel can be connected to various input streams and four of them can
160  * be selected by electronic straps on the display. However it is possible
161  * to select another mode or override the electronic default with this
162  * setting.
163  */
164 enum ili9322_input {
165 	ILI9322_INPUT_SRGB_THROUGH = 0x0,
166 	ILI9322_INPUT_SRGB_ALIGNED = 0x1,
167 	ILI9322_INPUT_SRGB_DUMMY_320X240 = 0x2,
168 	ILI9322_INPUT_SRGB_DUMMY_360X240 = 0x3,
169 	ILI9322_INPUT_DISABLED_1 = 0x4,
170 	ILI9322_INPUT_PRGB_THROUGH = 0x5,
171 	ILI9322_INPUT_PRGB_ALIGNED = 0x6,
172 	ILI9322_INPUT_YUV_640X320_YCBCR = 0x7,
173 	ILI9322_INPUT_YUV_720X360_YCBCR = 0x8,
174 	ILI9322_INPUT_DISABLED_2 = 0x9,
175 	ILI9322_INPUT_ITU_R_BT656_720X360_YCBCR = 0xa,
176 	ILI9322_INPUT_ITU_R_BT656_640X320_YCBCR = 0xb,
177 	ILI9322_INPUT_UNKNOWN = 0xc,
178 };
179 
180 static const char * const ili9322_inputs[] = {
181 	"8 bit serial RGB through",
182 	"8 bit serial RGB aligned",
183 	"8 bit serial RGB dummy 320x240",
184 	"8 bit serial RGB dummy 360x240",
185 	"disabled 1",
186 	"24 bit parallel RGB through",
187 	"24 bit parallel RGB aligned",
188 	"24 bit YUV 640Y 320CbCr",
189 	"24 bit YUV 720Y 360CbCr",
190 	"disabled 2",
191 	"8 bit ITU-R BT.656 720Y 360CbCr",
192 	"8 bit ITU-R BT.656 640Y 320CbCr",
193 };
194 
195 /**
196  * struct ili9322_config - the system specific ILI9322 configuration
197  * @width_mm: physical panel width [mm]
198  * @height_mm: physical panel height [mm]
199  * @flip_horizontal: flip the image horizontally (right-to-left scan)
200  * (only in RGB and YUV modes)
201  * @flip_vertical: flip the image vertically (down-to-up scan)
202  * (only in RGB and YUV modes)
203  * @input: the input/entry type used in this system, if this is set to
204  * ILI9322_INPUT_UNKNOWN the driver will try to figure it out by probing
205  * the hardware
206  * @vreg1out_mv: the output in microvolts for the VREGOUT1 regulator used
207  * to drive the physical display. Valid ranges are 3600 thru 6000 in 100
208  * microvolt increments. If not specified, hardware defaults will be
209  * used (4.5V).
210  * @vcom_high_percent: the percentage of VREGOUT1 used for the peak
211  * voltage on the communications link. Valid ranges are 37 thru 100
212  * percent. If not specified, hardware defaults will be used (91%).
213  * @vcom_amplitude_percent: the percentage of VREGOUT1 used for the
214  * peak-to-peak amplitude of the communcation signals to the physical
215  * display. Valid ranges are 70 thru 132 percent in increments if two
216  * percent. Odd percentages will be truncated. If not specified, hardware
217  * defaults will be used (114%).
218  * @dclk_active_high: data/pixel clock active high, data will be clocked
219  * in on the rising edge of the DCLK (this is usually the case).
220  * @syncmode: The synchronization mode, what sync signals are emitted.
221  * See the enum for details.
222  * @de_active_high: DE (data entry) is active high
223  * @hsync_active_high: HSYNC is active high
224  * @vsync_active_high: VSYNC is active high
225  * @gamma_corr_pos: a set of 8 nybbles describing positive
226  * gamma correction for voltages V1 thru V8. Valid range 0..15
227  * @gamma_corr_neg: a set of 8 nybbles describing negative
228  * gamma correction for voltages V1 thru V8. Valid range 0..15
229  *
230  * These adjust what grayscale voltage will be output for input data V1 = 0,
231  * V2 = 16, V3 = 48, V4 = 96, V5 = 160, V6 = 208, V7 = 240 and V8 = 255.
232  * The curve is shaped like this:
233  *
234  *  ^
235  *  |                                                        V8
236  *  |                                                   V7
237  *  |                                          V6
238  *  |                               V5
239  *  |                    V4
240  *  |            V3
241  *  |     V2
242  *  | V1
243  *  +----------------------------------------------------------->
244  *    0   16     48      96         160        208      240  255
245  *
246  * The negative and postive gamma values adjust the V1 thru V8 up/down
247  * according to the datasheet specifications. This is a property of the
248  * physical display connected to the display controller and may vary.
249  * If defined, both arrays must be supplied in full. If the properties
250  * are not supplied, hardware defaults will be used.
251  */
252 struct ili9322_config {
253 	u32 width_mm;
254 	u32 height_mm;
255 	bool flip_horizontal;
256 	bool flip_vertical;
257 	enum ili9322_input input;
258 	u32 vreg1out_mv;
259 	u32 vcom_high_percent;
260 	u32 vcom_amplitude_percent;
261 	bool dclk_active_high;
262 	bool de_active_high;
263 	bool hsync_active_high;
264 	bool vsync_active_high;
265 	u8 syncmode;
266 	u8 gamma_corr_pos[8];
267 	u8 gamma_corr_neg[8];
268 };
269 
270 struct ili9322 {
271 	struct device *dev;
272 	const struct ili9322_config *conf;
273 	struct drm_panel panel;
274 	struct regmap *regmap;
275 	struct regulator_bulk_data supplies[3];
276 	struct gpio_desc *reset_gpio;
277 	enum ili9322_input input;
278 	struct videomode vm;
279 	u8 gamma[8];
280 	u8 vreg1out;
281 	u8 vcom_high;
282 	u8 vcom_amplitude;
283 };
284 
285 static inline struct ili9322 *panel_to_ili9322(struct drm_panel *panel)
286 {
287 	return container_of(panel, struct ili9322, panel);
288 }
289 
290 static int ili9322_regmap_spi_write(void *context, const void *data,
291 				    size_t count)
292 {
293 	struct device *dev = context;
294 	struct spi_device *spi = to_spi_device(dev);
295 	u8 buf[2];
296 
297 	/* Clear bit 7 to write */
298 	memcpy(buf, data, 2);
299 	buf[0] &= ~0x80;
300 
301 	dev_dbg(dev, "WRITE: %02x %02x\n", buf[0], buf[1]);
302 	return spi_write_then_read(spi, buf, 2, NULL, 0);
303 }
304 
305 static int ili9322_regmap_spi_read(void *context, const void *reg,
306 				   size_t reg_size, void *val, size_t val_size)
307 {
308 	struct device *dev = context;
309 	struct spi_device *spi = to_spi_device(dev);
310 	u8 buf[1];
311 
312 	/* Set bit 7 to 1 to read */
313 	memcpy(buf, reg, 1);
314 	dev_dbg(dev, "READ: %02x reg size = %zu, val size = %zu\n",
315 		buf[0], reg_size, val_size);
316 	buf[0] |= 0x80;
317 
318 	return spi_write_then_read(spi, buf, 1, val, 1);
319 }
320 
321 static const struct regmap_bus ili9322_regmap_bus = {
322 	.write = ili9322_regmap_spi_write,
323 	.read = ili9322_regmap_spi_read,
324 	.reg_format_endian_default = REGMAP_ENDIAN_BIG,
325 	.val_format_endian_default = REGMAP_ENDIAN_BIG,
326 };
327 
328 static bool ili9322_writeable_reg(struct device *dev, unsigned int reg)
329 {
330 	/* Just register 0 is read-only */
331 	if (reg == 0x00)
332 		return false;
333 	return true;
334 }
335 
336 static const struct regmap_config ili9322_regmap_config = {
337 	.reg_bits = 8,
338 	.val_bits = 8,
339 	.max_register = 0x44,
340 	.cache_type = REGCACHE_MAPLE,
341 	.writeable_reg = ili9322_writeable_reg,
342 };
343 
344 static int ili9322_init(struct drm_panel *panel, struct ili9322 *ili)
345 {
346 	u8 reg;
347 	int ret;
348 	int i;
349 
350 	/* Reset display */
351 	ret = regmap_write(ili->regmap, ILI9322_GLOBAL_RESET,
352 			   ILI9322_GLOBAL_RESET_ASSERT);
353 	if (ret) {
354 		dev_err(ili->dev, "can't issue GRESET (%d)\n", ret);
355 		return ret;
356 	}
357 
358 	/* Set up the main voltage regulator */
359 	if (ili->vreg1out != U8_MAX) {
360 		ret = regmap_write(ili->regmap, ILI9322_VREG1_VOLTAGE,
361 				   ili->vreg1out);
362 		if (ret) {
363 			dev_err(ili->dev, "can't set up VREG1OUT (%d)\n", ret);
364 			return ret;
365 		}
366 	}
367 
368 	if (ili->vcom_amplitude != U8_MAX) {
369 		ret = regmap_write(ili->regmap, ILI9322_VCOM_AMP,
370 				   ili->vcom_amplitude);
371 		if (ret) {
372 			dev_err(ili->dev,
373 				"can't set up VCOM amplitude (%d)\n", ret);
374 			return ret;
375 		}
376 	}
377 
378 	if (ili->vcom_high != U8_MAX) {
379 		ret = regmap_write(ili->regmap, ILI9322_VCOM_HIGH,
380 				   ili->vcom_high);
381 		if (ret) {
382 			dev_err(ili->dev, "can't set up VCOM high (%d)\n", ret);
383 			return ret;
384 		}
385 	}
386 
387 	/* Set up gamma correction */
388 	for (i = 0; i < ARRAY_SIZE(ili->gamma); i++) {
389 		ret = regmap_write(ili->regmap, ILI9322_GAMMA_1 + i,
390 				   ili->gamma[i]);
391 		if (ret) {
392 			dev_err(ili->dev,
393 				"can't write gamma V%d to 0x%02x (%d)\n",
394 				i + 1, ILI9322_GAMMA_1 + i, ret);
395 			return ret;
396 		}
397 	}
398 
399 	/*
400 	 * Polarity and inverted color order for RGB input.
401 	 * None of this applies in the BT.656 mode.
402 	 */
403 	reg = 0;
404 	if (ili->conf->dclk_active_high)
405 		reg = ILI9322_POL_DCLK;
406 	if (ili->conf->de_active_high)
407 		reg |= ILI9322_POL_DE;
408 	if (ili->conf->hsync_active_high)
409 		reg |= ILI9322_POL_HSYNC;
410 	if (ili->conf->vsync_active_high)
411 		reg |= ILI9322_POL_VSYNC;
412 	ret = regmap_write(ili->regmap, ILI9322_POL, reg);
413 	if (ret) {
414 		dev_err(ili->dev, "can't write POL register (%d)\n", ret);
415 		return ret;
416 	}
417 
418 	/*
419 	 * Set up interface control.
420 	 * This is not used in the BT.656 mode (no H/Vsync or DE signals).
421 	 */
422 	reg = ili->conf->syncmode;
423 	reg |= ILI9322_IF_CTRL_LINE_INVERSION;
424 	ret = regmap_write(ili->regmap, ILI9322_IF_CTRL, reg);
425 	if (ret) {
426 		dev_err(ili->dev, "can't write IF CTRL register (%d)\n", ret);
427 		return ret;
428 	}
429 
430 	/* Set up the input mode */
431 	reg = (ili->input << 4);
432 	/* These are inverted, setting to 1 is the default, clearing flips */
433 	if (!ili->conf->flip_horizontal)
434 		reg |= ILI9322_ENTRY_HDIR;
435 	if (!ili->conf->flip_vertical)
436 		reg |= ILI9322_ENTRY_VDIR;
437 	reg |= ILI9322_ENTRY_AUTODETECT;
438 	ret = regmap_write(ili->regmap, ILI9322_ENTRY, reg);
439 	if (ret) {
440 		dev_err(ili->dev, "can't write ENTRY reg (%d)\n", ret);
441 		return ret;
442 	}
443 	dev_info(ili->dev, "display is in %s mode, syncmode %02x\n",
444 		 ili9322_inputs[ili->input],
445 		 ili->conf->syncmode);
446 
447 	dev_info(ili->dev, "initialized display\n");
448 
449 	return 0;
450 }
451 
452 /*
453  * This power-on sequence if from the datasheet, page 57.
454  */
455 static int ili9322_power_on(struct ili9322 *ili)
456 {
457 	int ret;
458 
459 	/* Assert RESET */
460 	gpiod_set_value(ili->reset_gpio, 1);
461 
462 	ret = regulator_bulk_enable(ARRAY_SIZE(ili->supplies), ili->supplies);
463 	if (ret < 0) {
464 		dev_err(ili->dev, "unable to enable regulators\n");
465 		return ret;
466 	}
467 	msleep(20);
468 
469 	/* De-assert RESET */
470 	gpiod_set_value(ili->reset_gpio, 0);
471 
472 	msleep(10);
473 
474 	return 0;
475 }
476 
477 static int ili9322_power_off(struct ili9322 *ili)
478 {
479 	return regulator_bulk_disable(ARRAY_SIZE(ili->supplies), ili->supplies);
480 }
481 
482 static int ili9322_disable(struct drm_panel *panel)
483 {
484 	struct ili9322 *ili = panel_to_ili9322(panel);
485 	int ret;
486 
487 	ret = regmap_write(ili->regmap, ILI9322_POW_CTRL,
488 			   ILI9322_POW_CTRL_STANDBY);
489 	if (ret) {
490 		dev_err(ili->dev, "unable to go to standby mode\n");
491 		return ret;
492 	}
493 
494 	return 0;
495 }
496 
497 static int ili9322_unprepare(struct drm_panel *panel)
498 {
499 	struct ili9322 *ili = panel_to_ili9322(panel);
500 
501 	return ili9322_power_off(ili);
502 }
503 
504 static int ili9322_prepare(struct drm_panel *panel)
505 {
506 	struct ili9322 *ili = panel_to_ili9322(panel);
507 	int ret;
508 
509 	ret = ili9322_power_on(ili);
510 	if (ret < 0)
511 		return ret;
512 
513 	ret = ili9322_init(panel, ili);
514 	if (ret < 0)
515 		ili9322_unprepare(panel);
516 
517 	return ret;
518 }
519 
520 static int ili9322_enable(struct drm_panel *panel)
521 {
522 	struct ili9322 *ili = panel_to_ili9322(panel);
523 	int ret;
524 
525 	ret = regmap_write(ili->regmap, ILI9322_POW_CTRL,
526 			   ILI9322_POW_CTRL_DEFAULT);
527 	if (ret) {
528 		dev_err(ili->dev, "unable to enable panel\n");
529 		return ret;
530 	}
531 
532 	return 0;
533 }
534 
535 /* Serial RGB modes */
536 static const struct drm_display_mode srgb_320x240_mode = {
537 	.clock = 24535,
538 	.hdisplay = 320,
539 	.hsync_start = 320 + 359,
540 	.hsync_end = 320 + 359 + 1,
541 	.htotal = 320 + 359 + 1 + 241,
542 	.vdisplay = 240,
543 	.vsync_start = 240 + 4,
544 	.vsync_end = 240 + 4 + 1,
545 	.vtotal = 262,
546 	.flags = 0,
547 };
548 
549 static const struct drm_display_mode srgb_360x240_mode = {
550 	.clock = 27000,
551 	.hdisplay = 360,
552 	.hsync_start = 360 + 35,
553 	.hsync_end = 360 + 35 + 1,
554 	.htotal = 360 + 35 + 1 + 241,
555 	.vdisplay = 240,
556 	.vsync_start = 240 + 21,
557 	.vsync_end = 240 + 21 + 1,
558 	.vtotal = 262,
559 	.flags = 0,
560 };
561 
562 /* This is the only mode listed for parallel RGB in the datasheet */
563 static const struct drm_display_mode prgb_320x240_mode = {
564 	.clock = 64000,
565 	.hdisplay = 320,
566 	.hsync_start = 320 + 38,
567 	.hsync_end = 320 + 38 + 1,
568 	.htotal = 320 + 38 + 1 + 50,
569 	.vdisplay = 240,
570 	.vsync_start = 240 + 4,
571 	.vsync_end = 240 + 4 + 1,
572 	.vtotal = 262,
573 	.flags = 0,
574 };
575 
576 /* YUV modes */
577 static const struct drm_display_mode yuv_640x320_mode = {
578 	.clock = 24540,
579 	.hdisplay = 640,
580 	.hsync_start = 640 + 252,
581 	.hsync_end = 640 + 252 + 1,
582 	.htotal = 640 + 252 + 1 + 28,
583 	.vdisplay = 320,
584 	.vsync_start = 320 + 4,
585 	.vsync_end = 320 + 4 + 1,
586 	.vtotal = 320 + 4 + 1 + 18,
587 	.flags = 0,
588 };
589 
590 static const struct drm_display_mode yuv_720x360_mode = {
591 	.clock = 27000,
592 	.hdisplay = 720,
593 	.hsync_start = 720 + 252,
594 	.hsync_end = 720 + 252 + 1,
595 	.htotal = 720 + 252 + 1 + 24,
596 	.vdisplay = 360,
597 	.vsync_start = 360 + 4,
598 	.vsync_end = 360 + 4 + 1,
599 	.vtotal = 360 + 4 + 1 + 18,
600 	.flags = 0,
601 };
602 
603 /* BT.656 VGA mode, 640x480 */
604 static const struct drm_display_mode itu_r_bt_656_640_mode = {
605 	.clock = 24540,
606 	.hdisplay = 640,
607 	.hsync_start = 640 + 3,
608 	.hsync_end = 640 + 3 + 1,
609 	.htotal = 640 + 3 + 1 + 272,
610 	.vdisplay = 480,
611 	.vsync_start = 480 + 4,
612 	.vsync_end = 480 + 4 + 1,
613 	.vtotal = 500,
614 	.flags = 0,
615 };
616 
617 /* BT.656 D1 mode 720x480 */
618 static const struct drm_display_mode itu_r_bt_656_720_mode = {
619 	.clock = 27000,
620 	.hdisplay = 720,
621 	.hsync_start = 720 + 3,
622 	.hsync_end = 720 + 3 + 1,
623 	.htotal = 720 + 3 + 1 + 272,
624 	.vdisplay = 480,
625 	.vsync_start = 480 + 4,
626 	.vsync_end = 480 + 4 + 1,
627 	.vtotal = 500,
628 	.flags = 0,
629 };
630 
631 static int ili9322_get_modes(struct drm_panel *panel,
632 			     struct drm_connector *connector)
633 {
634 	struct ili9322 *ili = panel_to_ili9322(panel);
635 	struct drm_device *drm = connector->dev;
636 	struct drm_display_mode *mode;
637 	struct drm_display_info *info;
638 
639 	info = &connector->display_info;
640 	info->width_mm = ili->conf->width_mm;
641 	info->height_mm = ili->conf->height_mm;
642 	if (ili->conf->dclk_active_high)
643 		info->bus_flags |= DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE;
644 	else
645 		info->bus_flags |= DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE;
646 
647 	if (ili->conf->de_active_high)
648 		info->bus_flags |= DRM_BUS_FLAG_DE_HIGH;
649 	else
650 		info->bus_flags |= DRM_BUS_FLAG_DE_LOW;
651 
652 	switch (ili->input) {
653 	case ILI9322_INPUT_SRGB_DUMMY_320X240:
654 		mode = drm_mode_duplicate(drm, &srgb_320x240_mode);
655 		break;
656 	case ILI9322_INPUT_SRGB_DUMMY_360X240:
657 		mode = drm_mode_duplicate(drm, &srgb_360x240_mode);
658 		break;
659 	case ILI9322_INPUT_PRGB_THROUGH:
660 	case ILI9322_INPUT_PRGB_ALIGNED:
661 		mode = drm_mode_duplicate(drm, &prgb_320x240_mode);
662 		break;
663 	case ILI9322_INPUT_YUV_640X320_YCBCR:
664 		mode = drm_mode_duplicate(drm, &yuv_640x320_mode);
665 		break;
666 	case ILI9322_INPUT_YUV_720X360_YCBCR:
667 		mode = drm_mode_duplicate(drm, &yuv_720x360_mode);
668 		break;
669 	case ILI9322_INPUT_ITU_R_BT656_720X360_YCBCR:
670 		mode = drm_mode_duplicate(drm, &itu_r_bt_656_720_mode);
671 		break;
672 	case ILI9322_INPUT_ITU_R_BT656_640X320_YCBCR:
673 		mode = drm_mode_duplicate(drm, &itu_r_bt_656_640_mode);
674 		break;
675 	default:
676 		mode = NULL;
677 		break;
678 	}
679 	if (!mode) {
680 		dev_err(panel->dev, "bad mode or failed to add mode\n");
681 		return -EINVAL;
682 	}
683 	drm_mode_set_name(mode);
684 	/*
685 	 * This is the preferred mode because most people are going
686 	 * to want to use the display with VGA type graphics.
687 	 */
688 	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
689 
690 	/* Set up the polarity */
691 	if (ili->conf->hsync_active_high)
692 		mode->flags |= DRM_MODE_FLAG_PHSYNC;
693 	else
694 		mode->flags |= DRM_MODE_FLAG_NHSYNC;
695 	if (ili->conf->vsync_active_high)
696 		mode->flags |= DRM_MODE_FLAG_PVSYNC;
697 	else
698 		mode->flags |= DRM_MODE_FLAG_NVSYNC;
699 
700 	mode->width_mm = ili->conf->width_mm;
701 	mode->height_mm = ili->conf->height_mm;
702 	drm_mode_probed_add(connector, mode);
703 
704 	return 1; /* Number of modes */
705 }
706 
707 static const struct drm_panel_funcs ili9322_drm_funcs = {
708 	.disable = ili9322_disable,
709 	.unprepare = ili9322_unprepare,
710 	.prepare = ili9322_prepare,
711 	.enable = ili9322_enable,
712 	.get_modes = ili9322_get_modes,
713 };
714 
715 static int ili9322_probe(struct spi_device *spi)
716 {
717 	struct device *dev = &spi->dev;
718 	struct ili9322 *ili;
719 	const struct regmap_config *regmap_config;
720 	u8 gamma;
721 	u32 val;
722 	int ret;
723 	int i;
724 
725 	ili = devm_kzalloc(dev, sizeof(struct ili9322), GFP_KERNEL);
726 	if (!ili)
727 		return -ENOMEM;
728 
729 	spi_set_drvdata(spi, ili);
730 
731 	ili->dev = dev;
732 
733 	/*
734 	 * Every new incarnation of this display must have a unique
735 	 * data entry for the system in this driver.
736 	 */
737 	ili->conf = of_device_get_match_data(dev);
738 	if (!ili->conf) {
739 		dev_err(dev, "missing device configuration\n");
740 		return -ENODEV;
741 	}
742 
743 	val = ili->conf->vreg1out_mv;
744 	if (!val) {
745 		/* Default HW value, do not touch (should be 4.5V) */
746 		ili->vreg1out = U8_MAX;
747 	} else {
748 		if (val < 3600) {
749 			dev_err(dev, "too low VREG1OUT\n");
750 			return -EINVAL;
751 		}
752 		if (val > 6000) {
753 			dev_err(dev, "too high VREG1OUT\n");
754 			return -EINVAL;
755 		}
756 		if ((val % 100) != 0) {
757 			dev_err(dev, "VREG1OUT is no even 100 microvolt\n");
758 			return -EINVAL;
759 		}
760 		val -= 3600;
761 		val /= 100;
762 		dev_dbg(dev, "VREG1OUT = 0x%02x\n", val);
763 		ili->vreg1out = val;
764 	}
765 
766 	val = ili->conf->vcom_high_percent;
767 	if (!val) {
768 		/* Default HW value, do not touch (should be 91%) */
769 		ili->vcom_high = U8_MAX;
770 	} else {
771 		if (val < 37) {
772 			dev_err(dev, "too low VCOM high\n");
773 			return -EINVAL;
774 		}
775 		if (val > 100) {
776 			dev_err(dev, "too high VCOM high\n");
777 			return -EINVAL;
778 		}
779 		val -= 37;
780 		dev_dbg(dev, "VCOM high = 0x%02x\n", val);
781 		ili->vcom_high = val;
782 	}
783 
784 	val = ili->conf->vcom_amplitude_percent;
785 	if (!val) {
786 		/* Default HW value, do not touch (should be 114%) */
787 		ili->vcom_high = U8_MAX;
788 	} else {
789 		if (val < 70) {
790 			dev_err(dev, "too low VCOM amplitude\n");
791 			return -EINVAL;
792 		}
793 		if (val > 132) {
794 			dev_err(dev, "too high VCOM amplitude\n");
795 			return -EINVAL;
796 		}
797 		val -= 70;
798 		val >>= 1; /* Increments of 2% */
799 		dev_dbg(dev, "VCOM amplitude = 0x%02x\n", val);
800 		ili->vcom_amplitude = val;
801 	}
802 
803 	for (i = 0; i < ARRAY_SIZE(ili->gamma); i++) {
804 		val = ili->conf->gamma_corr_neg[i];
805 		if (val > 15) {
806 			dev_err(dev, "negative gamma %u > 15, capping\n", val);
807 			val = 15;
808 		}
809 		gamma = val << 4;
810 		val = ili->conf->gamma_corr_pos[i];
811 		if (val > 15) {
812 			dev_err(dev, "positive gamma %u > 15, capping\n", val);
813 			val = 15;
814 		}
815 		gamma |= val;
816 		ili->gamma[i] = gamma;
817 		dev_dbg(dev, "gamma V%d: 0x%02x\n", i + 1, gamma);
818 	}
819 
820 	ili->supplies[0].supply = "vcc"; /* 2.7-3.6 V */
821 	ili->supplies[1].supply = "iovcc"; /* 1.65-3.6V */
822 	ili->supplies[2].supply = "vci"; /* 2.7-3.6V */
823 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ili->supplies),
824 				      ili->supplies);
825 	if (ret < 0)
826 		return ret;
827 	ret = regulator_set_voltage(ili->supplies[0].consumer,
828 				    2700000, 3600000);
829 	if (ret)
830 		return ret;
831 	ret = regulator_set_voltage(ili->supplies[1].consumer,
832 				    1650000, 3600000);
833 	if (ret)
834 		return ret;
835 	ret = regulator_set_voltage(ili->supplies[2].consumer,
836 				    2700000, 3600000);
837 	if (ret)
838 		return ret;
839 
840 	ili->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
841 	if (IS_ERR(ili->reset_gpio)) {
842 		dev_err(dev, "failed to get RESET GPIO\n");
843 		return PTR_ERR(ili->reset_gpio);
844 	}
845 
846 	spi->bits_per_word = 8;
847 	ret = spi_setup(spi);
848 	if (ret < 0) {
849 		dev_err(dev, "spi setup failed.\n");
850 		return ret;
851 	}
852 	regmap_config = &ili9322_regmap_config;
853 	ili->regmap = devm_regmap_init(dev, &ili9322_regmap_bus, dev,
854 				       regmap_config);
855 	if (IS_ERR(ili->regmap)) {
856 		dev_err(dev, "failed to allocate register map\n");
857 		return PTR_ERR(ili->regmap);
858 	}
859 
860 	ret = regmap_read(ili->regmap, ILI9322_CHIP_ID, &val);
861 	if (ret) {
862 		dev_err(dev, "can't get chip ID (%d)\n", ret);
863 		return ret;
864 	}
865 	if (val != ILI9322_CHIP_ID_MAGIC) {
866 		dev_err(dev, "chip ID 0x%0x2, expected 0x%02x\n", val,
867 			ILI9322_CHIP_ID_MAGIC);
868 		return -ENODEV;
869 	}
870 
871 	/* Probe the system to find the display setting */
872 	if (ili->conf->input == ILI9322_INPUT_UNKNOWN) {
873 		ret = regmap_read(ili->regmap, ILI9322_ENTRY, &val);
874 		if (ret) {
875 			dev_err(dev, "can't get entry setting (%d)\n", ret);
876 			return ret;
877 		}
878 		/* Input enum corresponds to HW setting */
879 		ili->input = (val >> 4) & 0x0f;
880 		if (ili->input >= ILI9322_INPUT_UNKNOWN)
881 			ili->input = ILI9322_INPUT_UNKNOWN;
882 	} else {
883 		ili->input = ili->conf->input;
884 	}
885 
886 	drm_panel_init(&ili->panel, dev, &ili9322_drm_funcs,
887 		       DRM_MODE_CONNECTOR_DPI);
888 
889 	drm_panel_add(&ili->panel);
890 
891 	return 0;
892 }
893 
894 static void ili9322_remove(struct spi_device *spi)
895 {
896 	struct ili9322 *ili = spi_get_drvdata(spi);
897 
898 	ili9322_power_off(ili);
899 	drm_panel_remove(&ili->panel);
900 }
901 
902 /*
903  * The D-Link DIR-685 panel is marked LM918A01-1A SY-B4-091116-E0199
904  */
905 static const struct ili9322_config ili9322_dir_685 = {
906 	.width_mm = 65,
907 	.height_mm = 50,
908 	.input = ILI9322_INPUT_ITU_R_BT656_640X320_YCBCR,
909 	.vreg1out_mv = 4600,
910 	.vcom_high_percent = 91,
911 	.vcom_amplitude_percent = 114,
912 	.syncmode = ILI9322_IF_CTRL_SYNC_DISABLED,
913 	.dclk_active_high = true,
914 	.gamma_corr_neg = { 0xa, 0x5, 0x7, 0x7, 0x7, 0x5, 0x1, 0x6 },
915 	.gamma_corr_pos = { 0x7, 0x7, 0x3, 0x2, 0x3, 0x5, 0x7, 0x2 },
916 };
917 
918 static const struct of_device_id ili9322_of_match[] = {
919 	{
920 		.compatible = "dlink,dir-685-panel",
921 		.data = &ili9322_dir_685,
922 	},
923 	{
924 		.compatible = "ilitek,ili9322",
925 		.data = NULL,
926 	},
927 	{ }
928 };
929 MODULE_DEVICE_TABLE(of, ili9322_of_match);
930 
931 static struct spi_driver ili9322_driver = {
932 	.probe = ili9322_probe,
933 	.remove = ili9322_remove,
934 	.driver = {
935 		.name = "panel-ilitek-ili9322",
936 		.of_match_table = ili9322_of_match,
937 	},
938 };
939 module_spi_driver(ili9322_driver);
940 
941 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
942 MODULE_DESCRIPTION("ILI9322 LCD panel driver");
943 MODULE_LICENSE("GPL v2");
944