1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Novatek NT35510 panel driver
4 * Copyright (C) 2020 Linus Walleij <linus.walleij@linaro.org>
5 * Based on code by Robert Teather (C) 2012 Samsung
6 *
7 * This display driver (and I refer to the physical component NT35510,
8 * not this Linux kernel software driver) can handle:
9 * 480x864, 480x854, 480x800, 480x720 and 480x640 pixel displays.
10 * It has 480x840x24bit SRAM embedded for storing a frame.
11 * When powered on the display is by default in 480x800 mode.
12 *
13 * The actual panels using this component have different names, but
14 * the code needed to set up and configure the panel will be similar,
15 * so they should all use the NT35510 driver with appropriate configuration
16 * per-panel, e.g. for physical size.
17 *
18 * This driver is for the DSI interface to panels using the NT35510.
19 *
20 * The NT35510 can also use an RGB (DPI) interface combined with an
21 * I2C or SPI interface for setting up the NT35510. If this is needed
22 * this panel driver should be refactored to also support that use
23 * case.
24 */
25#include <linux/backlight.h>
26#include <linux/bitops.h>
27#include <linux/gpio/consumer.h>
28#include <linux/module.h>
29#include <linux/of.h>
30#include <linux/regmap.h>
31#include <linux/regulator/consumer.h>
32
33#include <video/mipi_display.h>
34
35#include <drm/drm_mipi_dsi.h>
36#include <drm/drm_modes.h>
37#include <drm/drm_panel.h>
38
39#define MCS_CMD_MAUCCTR		0xF0 /* Manufacturer command enable */
40#define MCS_CMD_READ_ID1	0xDA
41#define MCS_CMD_READ_ID2	0xDB
42#define MCS_CMD_READ_ID3	0xDC
43#define MCS_CMD_MTP_READ_SETTING 0xF8 /* Uncertain about name */
44#define MCS_CMD_MTP_READ_PARAM 0xFF /* Uncertain about name */
45
46/*
47 * These manufacturer commands are available after we enable manufacturer
48 * command set (MCS) for page 0.
49 */
50#define NT35510_P0_DOPCTR 0xB1
51#define NT35510_P0_SDHDTCTR 0xB6
52#define NT35510_P0_GSEQCTR 0xB7
53#define NT35510_P0_SDEQCTR 0xB8
54#define NT35510_P0_SDVPCTR 0xBA
55#define NT35510_P0_DPFRCTR1 0xBD
56#define NT35510_P0_DPFRCTR2 0xBE
57#define NT35510_P0_DPFRCTR3 0xBF
58#define NT35510_P0_DPMCTR12 0xCC
59
60#define NT35510_P0_DOPCTR_LEN 2
61#define NT35510_P0_GSEQCTR_LEN 2
62#define NT35510_P0_SDEQCTR_LEN 4
63#define NT35510_P0_SDVPCTR_LEN 1
64#define NT35510_P0_DPFRCTR1_LEN 5
65#define NT35510_P0_DPFRCTR2_LEN 5
66#define NT35510_P0_DPFRCTR3_LEN 5
67#define NT35510_P0_DPMCTR12_LEN 3
68
69#define NT35510_DOPCTR_0_RAMKP BIT(7) /* Contents kept in sleep */
70#define NT35510_DOPCTR_0_DSITE BIT(6) /* Enable TE signal */
71#define NT35510_DOPCTR_0_DSIG BIT(5) /* Enable generic read/write */
72#define NT35510_DOPCTR_0_DSIM BIT(4) /* Enable video mode on DSI */
73#define NT35510_DOPCTR_0_EOTP BIT(3) /* Support EoTP */
74#define NT35510_DOPCTR_0_N565 BIT(2) /* RGB or BGR pixel format */
75#define NT35510_DOPCTR_1_TW_PWR_SEL BIT(4) /* TE power selector */
76#define NT35510_DOPCTR_1_CRGB BIT(3) /* RGB or BGR byte order */
77#define NT35510_DOPCTR_1_CTB BIT(2) /* Vertical scanning direction */
78#define NT35510_DOPCTR_1_CRL BIT(1) /* Source driver data shift */
79#define NT35510_P0_SDVPCTR_PRG BIT(2) /* 0 = normal operation, 1 = VGLO */
80#define NT35510_P0_SDVPCTR_AVDD 0 /* source driver output = AVDD */
81#define NT35510_P0_SDVPCTR_OFFCOL 1 /* source driver output = off color */
82#define NT35510_P0_SDVPCTR_AVSS 2 /* source driver output = AVSS */
83#define NT35510_P0_SDVPCTR_HI_Z 3 /* source driver output = High impedance */
84
85/*
86 * These manufacturer commands are available after we enable manufacturer
87 * command set (MCS) for page 1.
88 */
89#define NT35510_P1_SETAVDD 0xB0
90#define NT35510_P1_SETAVEE 0xB1
91#define NT35510_P1_SETVCL 0xB2
92#define NT35510_P1_SETVGH 0xB3
93#define NT35510_P1_SETVRGH 0xB4
94#define NT35510_P1_SETVGL 0xB5
95#define NT35510_P1_BT1CTR 0xB6
96#define NT35510_P1_BT2CTR 0xB7
97#define NT35510_P1_BT3CTR 0xB8
98#define NT35510_P1_BT4CTR 0xB9 /* VGH boosting times/freq */
99#define NT35510_P1_BT5CTR 0xBA
100#define NT35510_P1_PFMCTR 0xBB
101#define NT35510_P1_SETVGP 0xBC
102#define NT35510_P1_SETVGN 0xBD
103#define NT35510_P1_SETVCMOFF 0xBE
104#define NT35510_P1_VGHCTR 0xBF /* VGH output ctrl */
105#define NT35510_P1_SET_GAMMA_RED_POS 0xD1
106#define NT35510_P1_SET_GAMMA_GREEN_POS 0xD2
107#define NT35510_P1_SET_GAMMA_BLUE_POS 0xD3
108#define NT35510_P1_SET_GAMMA_RED_NEG 0xD4
109#define NT35510_P1_SET_GAMMA_GREEN_NEG 0xD5
110#define NT35510_P1_SET_GAMMA_BLUE_NEG 0xD6
111
112/* AVDD and AVEE setting 3 bytes */
113#define NT35510_P1_AVDD_LEN 3
114#define NT35510_P1_AVEE_LEN 3
115#define NT35510_P1_VGH_LEN 3
116#define NT35510_P1_VGL_LEN 3
117#define NT35510_P1_VGP_LEN 3
118#define NT35510_P1_VGN_LEN 3
119/* BT1CTR thru BT5CTR setting 3 bytes */
120#define NT35510_P1_BT1CTR_LEN 3
121#define NT35510_P1_BT2CTR_LEN 3
122#define NT35510_P1_BT4CTR_LEN 3
123#define NT35510_P1_BT5CTR_LEN 3
124/* 52 gamma parameters times two per color: positive and negative */
125#define NT35510_P1_GAMMA_LEN 52
126
127/**
128 * struct nt35510_config - the display-specific NT35510 configuration
129 *
130 * Some of the settings provide an array of bytes, A, B C which mean:
131 * A = normal / idle off mode
132 * B = idle on mode
133 * C = partial / idle off mode
134 *
135 * Gamma correction arrays are 10bit numbers, two consecutive bytes
136 * makes out one point on the gamma correction curve. The points are
137 * not linearly placed along the X axis, we get points 0, 1, 3, 5
138 * 7, 11, 15, 23, 31, 47, 63, 95, 127, 128, 160, 192, 208, 224, 232,
139 * 240, 244, 248, 250, 252, 254, 255. The voltages tuples form
140 * V0, V1, V3 ... V255, with 0x0000 being the lowest voltage and
141 * 0x03FF being the highest voltage.
142 *
143 * Each value must be strictly higher than the previous value forming
144 * a rising curve like this:
145 *
146 * ^
147 * |                                        V255
148 * |                                 V254
149 * |                         ....
150 * |                    V5
151 * |           V3
152 * |     V1
153 * | V0
154 * +------------------------------------------->
155 *
156 * The details about all settings can be found in the NT35510 Application
157 * Note.
158 */
159struct nt35510_config {
160	/**
161	 * @width_mm: physical panel width [mm]
162	 */
163	u32 width_mm;
164	/**
165	 * @height_mm: physical panel height [mm]
166	 */
167	u32 height_mm;
168	/**
169	 * @mode: the display mode. This is only relevant outside the panel
170	 * in video mode: in command mode this is configuring the internal
171	 * timing in the display controller.
172	 */
173	const struct drm_display_mode mode;
174	/**
175	 * @avdd: setting for AVDD ranging from 0x00 = 6.5V to 0x14 = 4.5V
176	 * in 0.1V steps the default is 0x05 which means 6.0V
177	 */
178	u8 avdd[NT35510_P1_AVDD_LEN];
179	/**
180	 * @bt1ctr: setting for boost power control for the AVDD step-up
181	 * circuit (1)
182	 * bits 0..2 in the lower nibble controls PCK, the booster clock
183	 * frequency for the step-up circuit:
184	 * 0 = Hsync/32
185	 * 1 = Hsync/16
186	 * 2 = Hsync/8
187	 * 3 = Hsync/4
188	 * 4 = Hsync/2
189	 * 5 = Hsync
190	 * 6 = Hsync x 2
191	 * 7 = Hsync x 4
192	 * bits 4..6 in the upper nibble controls BTP, the boosting
193	 * amplification for the step-up circuit:
194	 * 0 = Disable
195	 * 1 = 1.5 x VDDB
196	 * 2 = 1.66 x VDDB
197	 * 3 = 2 x VDDB
198	 * 4 = 2.5 x VDDB
199	 * 5 = 3 x VDDB
200	 * The defaults are 4 and 4 yielding 0x44
201	 */
202	u8 bt1ctr[NT35510_P1_BT1CTR_LEN];
203	/**
204	 * @avee: setting for AVEE ranging from 0x00 = -6.5V to 0x14 = -4.5V
205	 * in 0.1V steps the default is 0x05 which means -6.0V
206	 */
207	u8 avee[NT35510_P1_AVEE_LEN];
208	/**
209	 * @bt2ctr: setting for boost power control for the AVEE step-up
210	 * circuit (2)
211	 * bits 0..2 in the lower nibble controls NCK, the booster clock
212	 * frequency, the values are the same as for PCK in @bt1ctr.
213	 * bits 4..5 in the upper nibble controls BTN, the boosting
214	 * amplification for the step-up circuit.
215	 * 0 = Disable
216	 * 1 = -1.5 x VDDB
217	 * 2 = -2 x VDDB
218	 * 3 = -2.5 x VDDB
219	 * 4 = -3 x VDDB
220	 * The defaults are 4 and 3 yielding 0x34
221	 */
222	u8 bt2ctr[NT35510_P1_BT2CTR_LEN];
223	/**
224	 * @vgh: setting for VGH ranging from 0x00 = 7.0V to 0x0B = 18.0V
225	 * in 1V steps, the default is 0x08 which means 15V
226	 */
227	u8 vgh[NT35510_P1_VGH_LEN];
228	/**
229	 * @bt4ctr: setting for boost power control for the VGH step-up
230	 * circuit (4)
231	 * bits 0..2 in the lower nibble controls HCK, the booster clock
232	 * frequency, the values are the same as for PCK in @bt1ctr.
233	 * bits 4..5 in the upper nibble controls BTH, the boosting
234	 * amplification for the step-up circuit.
235	 * 0 = AVDD + VDDB
236	 * 1 = AVDD - AVEE
237	 * 2 = AVDD - AVEE + VDDB
238	 * 3 = AVDD x 2 - AVEE
239	 * The defaults are 4 and 3 yielding 0x34
240	 */
241	u8 bt4ctr[NT35510_P1_BT4CTR_LEN];
242	/**
243	 * @vgl: setting for VGL ranging from 0x00 = -2V to 0x0f = -15V in
244	 * 1V steps, the default is 0x08 which means -10V
245	 */
246	u8 vgl[NT35510_P1_VGL_LEN];
247	/**
248	 * @bt5ctr: setting for boost power control for the VGL step-up
249	 * circuit (5)
250	 * bits 0..2 in the lower nibble controls LCK, the booster clock
251	 * frequency, the values are the same as for PCK in @bt1ctr.
252	 * bits 4..5 in the upper nibble controls BTL, the boosting
253	 * amplification for the step-up circuit.
254	 * 0 = AVEE + VCL
255	 * 1 = AVEE - AVDD
256	 * 2 = AVEE + VCL - AVDD
257	 * 3 = AVEE x 2 - AVDD
258	 * The defaults are 3 and 2 yielding 0x32
259	 */
260	u8 bt5ctr[NT35510_P1_BT5CTR_LEN];
261	/**
262	 * @vgp: setting for VGP, the positive gamma divider voltages
263	 * VGMP the high voltage and VGSP the low voltage.
264	 * The first byte contains bit 8 of VGMP and VGSP in bits 4 and 0
265	 * The second byte contains bit 0..7 of VGMP
266	 * The third byte contains bit 0..7 of VGSP
267	 * VGMP 0x00 = 3.0V .. 0x108 = 6.3V in steps of 12.5mV
268	 * VGSP 0x00 = 0V .. 0x111 = 3.7V in steps of 12.5mV
269	 */
270	u8 vgp[NT35510_P1_VGP_LEN];
271	/**
272	 * @vgn: setting for VGN, the negative gamma divider voltages,
273	 * same layout of bytes as @vgp.
274	 */
275	u8 vgn[NT35510_P1_VGN_LEN];
276	/**
277	 * @sdeqctr: Source driver control settings, first byte is
278	 * 0 for mode 1 and 1 for mode 2. Mode 1 uses two steps and
279	 * mode 2 uses three steps meaning EQS3 is not used in mode
280	 * 1. Mode 2 is default. The last three parameters are EQS1, EQS2
281	 * and EQS3, setting the rise time for each equalizer step:
282	 * 0x00 = 0.0 us to 0x0f = 7.5 us in steps of 0.5us. The default
283	 * is 0x07 = 3.5 us.
284	 */
285	u8 sdeqctr[NT35510_P0_SDEQCTR_LEN];
286	/**
287	 * @sdvpctr: power/voltage behaviour during vertical porch time
288	 */
289	u8 sdvpctr;
290	/**
291	 * @t1: the number of pixel clocks on one scanline, range
292	 * 0x100 (258 ticks) .. 0x3FF (1024 ticks) so the value + 1
293	 * clock ticks.
294	 */
295	u16 t1;
296	/**
297	 * @vbp: vertical back porch toward the PANEL note: not toward
298	 * the DSI host; these are separate interfaces, in from DSI host
299	 * and out to the panel.
300	 */
301	u8 vbp;
302	/**
303	 * @vfp: vertical front porch toward the PANEL.
304	 */
305	u8 vfp;
306	/**
307	 * @psel: pixel clock divisor: 0 = 1, 1 = 2, 2 = 4, 3 = 8.
308	 */
309	u8 psel;
310	/**
311	 * @dpmctr12: Display timing control 12
312	 * Byte 1 bit 4 selects LVGL voltage level: 0 = VGLX, 1 = VGL_REG
313	 * Byte 1 bit 1 selects gate signal mode: 0 = non-overlap, 1 = overlap
314	 * Byte 1 bit 0 selects output signal control R/L swap, 0 = normal
315	 * 1 = swap all O->E, L->R
316	 * Byte 2 is CLW delay clock for CK O/E and CKB O/E signals:
317	 * 0x00 = 0us .. 0xFF = 12.75us in 0.05us steps
318	 * Byte 3 is FTI_H0 delay time for STP O/E signals:
319	 * 0x00 = 0us .. 0xFF = 12.75us in 0.05us steps
320	 */
321	u8 dpmctr12[NT35510_P0_DPMCTR12_LEN];
322	/**
323	 * @gamma_corr_pos_r: Red gamma correction parameters, positive
324	 */
325	u8 gamma_corr_pos_r[NT35510_P1_GAMMA_LEN];
326	/**
327	 * @gamma_corr_pos_g: Green gamma correction parameters, positive
328	 */
329	u8 gamma_corr_pos_g[NT35510_P1_GAMMA_LEN];
330	/**
331	 * @gamma_corr_pos_b: Blue gamma correction parameters, positive
332	 */
333	u8 gamma_corr_pos_b[NT35510_P1_GAMMA_LEN];
334	/**
335	 * @gamma_corr_neg_r: Red gamma correction parameters, negative
336	 */
337	u8 gamma_corr_neg_r[NT35510_P1_GAMMA_LEN];
338	/**
339	 * @gamma_corr_neg_g: Green gamma correction parameters, negative
340	 */
341	u8 gamma_corr_neg_g[NT35510_P1_GAMMA_LEN];
342	/**
343	 * @gamma_corr_neg_b: Blue gamma correction parameters, negative
344	 */
345	u8 gamma_corr_neg_b[NT35510_P1_GAMMA_LEN];
346};
347
348/**
349 * struct nt35510 - state container for the NT35510 panel
350 */
351struct nt35510 {
352	/**
353	 * @dev: the container device
354	 */
355	struct device *dev;
356	/**
357	 * @conf: the specific panel configuration, as the NT35510
358	 * can be combined with many physical panels, they can have
359	 * different physical dimensions and gamma correction etc,
360	 * so this is stored in the config.
361	 */
362	const struct nt35510_config *conf;
363	/**
364	 * @panel: the DRM panel object for the instance
365	 */
366	struct drm_panel panel;
367	/**
368	 * @supplies: regulators supplying the panel
369	 */
370	struct regulator_bulk_data supplies[2];
371	/**
372	 * @reset_gpio: the reset line
373	 */
374	struct gpio_desc *reset_gpio;
375};
376
377/* Manufacturer command has strictly this byte sequence */
378static const u8 nt35510_mauc_mtp_read_param[] = { 0xAA, 0x55, 0x25, 0x01 };
379static const u8 nt35510_mauc_mtp_read_setting[] = { 0x01, 0x02, 0x00, 0x20,
380						    0x33, 0x13, 0x00, 0x40,
381						    0x00, 0x00, 0x23, 0x02 };
382static const u8 nt35510_mauc_select_page_0[] = { 0x55, 0xAA, 0x52, 0x08, 0x00 };
383static const u8 nt35510_mauc_select_page_1[] = { 0x55, 0xAA, 0x52, 0x08, 0x01 };
384static const u8 nt35510_vgh_on[] = { 0x01 };
385
386static inline struct nt35510 *panel_to_nt35510(struct drm_panel *panel)
387{
388	return container_of(panel, struct nt35510, panel);
389}
390
391#define NT35510_ROTATE_0_SETTING	0x02
392#define NT35510_ROTATE_180_SETTING	0x00
393
394static int nt35510_send_long(struct nt35510 *nt, struct mipi_dsi_device *dsi,
395			     u8 cmd, u8 cmdlen, const u8 *seq)
396{
397	const u8 *seqp = seq;
398	int cmdwritten = 0;
399	int chunk = cmdlen;
400	int ret;
401
402	if (chunk > 15)
403		chunk = 15;
404	ret = mipi_dsi_dcs_write(dsi, cmd, seqp, chunk);
405	if (ret < 0) {
406		dev_err(nt->dev, "error sending DCS command seq cmd %02x\n", cmd);
407		return ret;
408	}
409	cmdwritten += chunk;
410	seqp += chunk;
411
412	while (cmdwritten < cmdlen) {
413		chunk = cmdlen - cmdwritten;
414		if (chunk > 15)
415			chunk = 15;
416		ret = mipi_dsi_generic_write(dsi, seqp, chunk);
417		if (ret < 0) {
418			dev_err(nt->dev, "error sending generic write seq %02x\n", cmd);
419			return ret;
420		}
421		cmdwritten += chunk;
422		seqp += chunk;
423	}
424	dev_dbg(nt->dev, "sent command %02x %02x bytes\n", cmd, cmdlen);
425	return 0;
426}
427
428static int nt35510_read_id(struct nt35510 *nt)
429{
430	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
431	u8 id1, id2, id3;
432	int ret;
433
434	ret = mipi_dsi_dcs_read(dsi, MCS_CMD_READ_ID1, &id1, 1);
435	if (ret < 0) {
436		dev_err(nt->dev, "could not read MTP ID1\n");
437		return ret;
438	}
439	ret = mipi_dsi_dcs_read(dsi, MCS_CMD_READ_ID2, &id2, 1);
440	if (ret < 0) {
441		dev_err(nt->dev, "could not read MTP ID2\n");
442		return ret;
443	}
444	ret = mipi_dsi_dcs_read(dsi, MCS_CMD_READ_ID3, &id3, 1);
445	if (ret < 0) {
446		dev_err(nt->dev, "could not read MTP ID3\n");
447		return ret;
448	}
449
450	/*
451	 * Multi-Time Programmable (?) memory contains manufacturer
452	 * ID (e.g. Hydis 0x55), driver ID (e.g. NT35510 0xc0) and
453	 * version.
454	 */
455	dev_info(nt->dev, "MTP ID manufacturer: %02x version: %02x driver: %02x\n", id1, id2, id3);
456
457	return 0;
458}
459
460/**
461 * nt35510_setup_power() - set up power config in page 1
462 * @nt: the display instance to set up
463 */
464static int nt35510_setup_power(struct nt35510 *nt)
465{
466	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
467	int ret;
468
469	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETAVDD,
470				NT35510_P1_AVDD_LEN,
471				nt->conf->avdd);
472	if (ret)
473		return ret;
474	ret = nt35510_send_long(nt, dsi, NT35510_P1_BT1CTR,
475				NT35510_P1_BT1CTR_LEN,
476				nt->conf->bt1ctr);
477	if (ret)
478		return ret;
479	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETAVEE,
480				NT35510_P1_AVEE_LEN,
481				nt->conf->avee);
482	if (ret)
483		return ret;
484	ret = nt35510_send_long(nt, dsi, NT35510_P1_BT2CTR,
485				NT35510_P1_BT2CTR_LEN,
486				nt->conf->bt2ctr);
487	if (ret)
488		return ret;
489	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETVGH,
490				NT35510_P1_VGH_LEN,
491				nt->conf->vgh);
492	if (ret)
493		return ret;
494	ret = nt35510_send_long(nt, dsi, NT35510_P1_BT4CTR,
495				NT35510_P1_BT4CTR_LEN,
496				nt->conf->bt4ctr);
497	if (ret)
498		return ret;
499	ret = nt35510_send_long(nt, dsi, NT35510_P1_VGHCTR,
500				ARRAY_SIZE(nt35510_vgh_on),
501				nt35510_vgh_on);
502	if (ret)
503		return ret;
504	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETVGL,
505				NT35510_P1_VGL_LEN,
506				nt->conf->vgl);
507	if (ret)
508		return ret;
509	ret = nt35510_send_long(nt, dsi, NT35510_P1_BT5CTR,
510				NT35510_P1_BT5CTR_LEN,
511				nt->conf->bt5ctr);
512	if (ret)
513		return ret;
514	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETVGP,
515				NT35510_P1_VGP_LEN,
516				nt->conf->vgp);
517	if (ret)
518		return ret;
519	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETVGN,
520				NT35510_P1_VGN_LEN,
521				nt->conf->vgn);
522	if (ret)
523		return ret;
524
525	/* Typically 10 ms */
526	usleep_range(10000, 20000);
527
528	return 0;
529}
530
531/**
532 * nt35510_setup_display() - set up display config in page 0
533 * @nt: the display instance to set up
534 */
535static int nt35510_setup_display(struct nt35510 *nt)
536{
537	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
538	const struct nt35510_config *conf = nt->conf;
539	u8 dopctr[NT35510_P0_DOPCTR_LEN];
540	u8 gseqctr[NT35510_P0_GSEQCTR_LEN];
541	u8 dpfrctr[NT35510_P0_DPFRCTR1_LEN];
542	/* FIXME: set up any rotation (assume none for now) */
543	u8 addr_mode = NT35510_ROTATE_0_SETTING;
544	u8 val;
545	int ret;
546
547	/* Enable TE, EoTP and RGB pixel format */
548	dopctr[0] = NT35510_DOPCTR_0_DSITE | NT35510_DOPCTR_0_EOTP |
549		NT35510_DOPCTR_0_N565;
550	dopctr[1] = NT35510_DOPCTR_1_CTB;
551	ret = nt35510_send_long(nt, dsi, NT35510_P0_DOPCTR,
552				NT35510_P0_DOPCTR_LEN,
553				dopctr);
554	if (ret)
555		return ret;
556
557	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_ADDRESS_MODE, &addr_mode,
558				 sizeof(addr_mode));
559	if (ret < 0)
560		return ret;
561
562	/*
563	 * Source data hold time, default 0x05 = 2.5us
564	 * 0x00..0x3F = 0 .. 31.5us in steps of 0.5us
565	 * 0x0A = 5us
566	 */
567	val = 0x0A;
568	ret = mipi_dsi_dcs_write(dsi, NT35510_P0_SDHDTCTR, &val,
569				 sizeof(val));
570	if (ret < 0)
571		return ret;
572
573	/* EQ control for gate signals, 0x00 = 0 us */
574	gseqctr[0] = 0x00;
575	gseqctr[1] = 0x00;
576	ret = nt35510_send_long(nt, dsi, NT35510_P0_GSEQCTR,
577				NT35510_P0_GSEQCTR_LEN,
578				gseqctr);
579	if (ret)
580		return ret;
581
582	ret = nt35510_send_long(nt, dsi, NT35510_P0_SDEQCTR,
583				NT35510_P0_SDEQCTR_LEN,
584				conf->sdeqctr);
585	if (ret)
586		return ret;
587
588	ret = mipi_dsi_dcs_write(dsi, NT35510_P0_SDVPCTR,
589				 &conf->sdvpctr, 1);
590	if (ret < 0)
591		return ret;
592
593	/*
594	 * Display timing control for active and idle off mode:
595	 * the first byte contains
596	 * the two high bits of T1A and second byte the low 8 bits, and
597	 * the valid range is 0x100 (257) to 0x3ff (1023) representing
598	 * 258..1024 (+1) pixel clock ticks for one scanline. At 20MHz pixel
599	 * clock this covers the range of 12.90us .. 51.20us in steps of
600	 * 0.05us, the default is 0x184 (388) representing 389 ticks.
601	 * The third byte is VBPDA, vertical back porch display active
602	 * and the fourth VFPDA, vertical front porch display active,
603	 * both given in number of scanlines in the range 0x02..0xff
604	 * for 2..255 scanlines. The fifth byte is 2 bits selecting
605	 * PSEL for active and idle off mode, how much the 20MHz clock
606	 * is divided by 0..3.  This needs to be adjusted to get the right
607	 * frame rate.
608	 */
609	dpfrctr[0] = (conf->t1 >> 8) & 0xFF;
610	dpfrctr[1] = conf->t1 & 0xFF;
611	/* Vertical back porch */
612	dpfrctr[2] = conf->vbp;
613	/* Vertical front porch */
614	dpfrctr[3] = conf->vfp;
615	dpfrctr[4] = conf->psel;
616	ret = nt35510_send_long(nt, dsi, NT35510_P0_DPFRCTR1,
617				NT35510_P0_DPFRCTR1_LEN,
618				dpfrctr);
619	if (ret)
620		return ret;
621	/* For idle and partial idle off mode we decrease front porch by one */
622	dpfrctr[3]--;
623	ret = nt35510_send_long(nt, dsi, NT35510_P0_DPFRCTR2,
624				NT35510_P0_DPFRCTR2_LEN,
625				dpfrctr);
626	if (ret)
627		return ret;
628	ret = nt35510_send_long(nt, dsi, NT35510_P0_DPFRCTR3,
629				NT35510_P0_DPFRCTR3_LEN,
630				dpfrctr);
631	if (ret)
632		return ret;
633
634	/* Enable TE on vblank */
635	ret = mipi_dsi_dcs_set_tear_on(dsi, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
636	if (ret)
637		return ret;
638
639	/* Turn on the pads? */
640	ret = nt35510_send_long(nt, dsi, NT35510_P0_DPMCTR12,
641				NT35510_P0_DPMCTR12_LEN,
642				conf->dpmctr12);
643	if (ret)
644		return ret;
645
646	return 0;
647}
648
649static int nt35510_set_brightness(struct backlight_device *bl)
650{
651	struct nt35510 *nt = bl_get_data(bl);
652	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
653	u8 brightness = bl->props.brightness;
654	int ret;
655
656	dev_dbg(nt->dev, "set brightness %d\n", brightness);
657	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
658				 &brightness,
659				 sizeof(brightness));
660	if (ret < 0)
661		return ret;
662
663	return 0;
664}
665
666static const struct backlight_ops nt35510_bl_ops = {
667	.update_status = nt35510_set_brightness,
668};
669
670/*
671 * This power-on sequence
672 */
673static int nt35510_power_on(struct nt35510 *nt)
674{
675	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
676	int ret;
677
678	ret = regulator_bulk_enable(ARRAY_SIZE(nt->supplies), nt->supplies);
679	if (ret < 0) {
680		dev_err(nt->dev, "unable to enable regulators\n");
681		return ret;
682	}
683
684	/* Toggle RESET in accordance with datasheet page 370 */
685	if (nt->reset_gpio) {
686		gpiod_set_value(nt->reset_gpio, 1);
687		/* Active min 10 us according to datasheet, let's say 20 */
688		usleep_range(20, 1000);
689		gpiod_set_value(nt->reset_gpio, 0);
690		/*
691		 * 5 ms during sleep mode, 120 ms during sleep out mode
692		 * according to datasheet, let's use 120-140 ms.
693		 */
694		usleep_range(120000, 140000);
695	}
696
697	ret = nt35510_send_long(nt, dsi, MCS_CMD_MTP_READ_PARAM,
698				ARRAY_SIZE(nt35510_mauc_mtp_read_param),
699				nt35510_mauc_mtp_read_param);
700	if (ret)
701		return ret;
702
703	ret = nt35510_send_long(nt, dsi, MCS_CMD_MTP_READ_SETTING,
704				ARRAY_SIZE(nt35510_mauc_mtp_read_setting),
705				nt35510_mauc_mtp_read_setting);
706	if (ret)
707		return ret;
708
709	nt35510_read_id(nt);
710
711	/* Set up stuff in  manufacturer control, page 1 */
712	ret = nt35510_send_long(nt, dsi, MCS_CMD_MAUCCTR,
713				ARRAY_SIZE(nt35510_mauc_select_page_1),
714				nt35510_mauc_select_page_1);
715	if (ret)
716		return ret;
717
718	ret = nt35510_setup_power(nt);
719	if (ret)
720		return ret;
721
722	ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_RED_POS,
723				NT35510_P1_GAMMA_LEN,
724				nt->conf->gamma_corr_pos_r);
725	if (ret)
726		return ret;
727	ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_GREEN_POS,
728				NT35510_P1_GAMMA_LEN,
729				nt->conf->gamma_corr_pos_g);
730	if (ret)
731		return ret;
732	ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_BLUE_POS,
733				NT35510_P1_GAMMA_LEN,
734				nt->conf->gamma_corr_pos_b);
735	if (ret)
736		return ret;
737	ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_RED_NEG,
738				NT35510_P1_GAMMA_LEN,
739				nt->conf->gamma_corr_neg_r);
740	if (ret)
741		return ret;
742	ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_GREEN_NEG,
743				NT35510_P1_GAMMA_LEN,
744				nt->conf->gamma_corr_neg_g);
745	if (ret)
746		return ret;
747	ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_BLUE_NEG,
748				NT35510_P1_GAMMA_LEN,
749				nt->conf->gamma_corr_neg_b);
750	if (ret)
751		return ret;
752
753	/* Set up stuff in  manufacturer control, page 0 */
754	ret = nt35510_send_long(nt, dsi, MCS_CMD_MAUCCTR,
755				ARRAY_SIZE(nt35510_mauc_select_page_0),
756				nt35510_mauc_select_page_0);
757	if (ret)
758		return ret;
759
760	ret = nt35510_setup_display(nt);
761	if (ret)
762		return ret;
763
764	return 0;
765}
766
767static int nt35510_power_off(struct nt35510 *nt)
768{
769	int ret;
770
771	ret = regulator_bulk_disable(ARRAY_SIZE(nt->supplies), nt->supplies);
772	if (ret)
773		return ret;
774
775	if (nt->reset_gpio)
776		gpiod_set_value(nt->reset_gpio, 1);
777
778	return 0;
779}
780
781static int nt35510_unprepare(struct drm_panel *panel)
782{
783	struct nt35510 *nt = panel_to_nt35510(panel);
784	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
785	int ret;
786
787	ret = mipi_dsi_dcs_set_display_off(dsi);
788	if (ret) {
789		dev_err(nt->dev, "failed to turn display off (%d)\n", ret);
790		return ret;
791	}
792	usleep_range(10000, 20000);
793
794	/* Enter sleep mode */
795	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
796	if (ret) {
797		dev_err(nt->dev, "failed to enter sleep mode (%d)\n", ret);
798		return ret;
799	}
800
801	/* Wait 4 frames, how much is that 5ms in the vendor driver */
802	usleep_range(5000, 10000);
803
804	ret = nt35510_power_off(nt);
805	if (ret)
806		return ret;
807
808	return 0;
809}
810
811static int nt35510_prepare(struct drm_panel *panel)
812{
813	struct nt35510 *nt = panel_to_nt35510(panel);
814	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
815	int ret;
816
817	ret = nt35510_power_on(nt);
818	if (ret)
819		return ret;
820
821	/* Exit sleep mode */
822	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
823	if (ret) {
824		dev_err(nt->dev, "failed to exit sleep mode (%d)\n", ret);
825		return ret;
826	}
827	/* Up to 120 ms */
828	usleep_range(120000, 150000);
829
830	ret = mipi_dsi_dcs_set_display_on(dsi);
831	if (ret) {
832		dev_err(nt->dev, "failed to turn display on (%d)\n", ret);
833		return ret;
834	}
835	/* Some 10 ms */
836	usleep_range(10000, 20000);
837
838	return 0;
839}
840
841static int nt35510_get_modes(struct drm_panel *panel,
842			     struct drm_connector *connector)
843{
844	struct nt35510 *nt = panel_to_nt35510(panel);
845	struct drm_display_mode *mode;
846	struct drm_display_info *info;
847
848	info = &connector->display_info;
849	info->width_mm = nt->conf->width_mm;
850	info->height_mm = nt->conf->height_mm;
851	mode = drm_mode_duplicate(connector->dev, &nt->conf->mode);
852	if (!mode) {
853		dev_err(panel->dev, "bad mode or failed to add mode\n");
854		return -EINVAL;
855	}
856	drm_mode_set_name(mode);
857	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
858
859	mode->width_mm = nt->conf->width_mm;
860	mode->height_mm = nt->conf->height_mm;
861	drm_mode_probed_add(connector, mode);
862
863	return 1; /* Number of modes */
864}
865
866static const struct drm_panel_funcs nt35510_drm_funcs = {
867	.unprepare = nt35510_unprepare,
868	.prepare = nt35510_prepare,
869	.get_modes = nt35510_get_modes,
870};
871
872static int nt35510_probe(struct mipi_dsi_device *dsi)
873{
874	struct device *dev = &dsi->dev;
875	struct nt35510 *nt;
876	int ret;
877
878	nt = devm_kzalloc(dev, sizeof(struct nt35510), GFP_KERNEL);
879	if (!nt)
880		return -ENOMEM;
881	mipi_dsi_set_drvdata(dsi, nt);
882	nt->dev = dev;
883
884	dsi->lanes = 2;
885	dsi->format = MIPI_DSI_FMT_RGB888;
886	/*
887	 * Datasheet suggests max HS rate for NT35510 is 250 MHz
888	 * (period time 4ns, see figure 7.6.4 page 365) and max LP rate is
889	 * 20 MHz (period time 50ns, see figure 7.6.6. page 366).
890	 * However these frequencies appear in source code for the Hydis
891	 * HVA40WV1 panel and setting up the LP frequency makes the panel
892	 * not work.
893	 *
894	 * TODO: if other panels prove to be closer to the datasheet,
895	 * maybe make this a per-panel config in struct nt35510_config?
896	 */
897	dsi->hs_rate = 349440000;
898	dsi->lp_rate = 9600000;
899	dsi->mode_flags = MIPI_DSI_CLOCK_NON_CONTINUOUS;
900
901	/*
902	 * Every new incarnation of this display must have a unique
903	 * data entry for the system in this driver.
904	 */
905	nt->conf = of_device_get_match_data(dev);
906	if (!nt->conf) {
907		dev_err(dev, "missing device configuration\n");
908		return -ENODEV;
909	}
910
911	nt->supplies[0].supply = "vdd"; /* 2.3-4.8 V */
912	nt->supplies[1].supply = "vddi"; /* 1.65-3.3V */
913	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(nt->supplies),
914				      nt->supplies);
915	if (ret < 0)
916		return ret;
917	ret = regulator_set_voltage(nt->supplies[0].consumer,
918				    2300000, 4800000);
919	if (ret)
920		return ret;
921	ret = regulator_set_voltage(nt->supplies[1].consumer,
922				    1650000, 3300000);
923	if (ret)
924		return ret;
925
926	nt->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_ASIS);
927	if (IS_ERR(nt->reset_gpio)) {
928		dev_err(dev, "error getting RESET GPIO\n");
929		return PTR_ERR(nt->reset_gpio);
930	}
931
932	drm_panel_init(&nt->panel, dev, &nt35510_drm_funcs,
933		       DRM_MODE_CONNECTOR_DSI);
934
935	/*
936	 * First, try to locate an external backlight (such as on GPIO)
937	 * if this fails, assume we will want to use the internal backlight
938	 * control.
939	 */
940	ret = drm_panel_of_backlight(&nt->panel);
941	if (ret) {
942		dev_err(dev, "error getting external backlight %d\n", ret);
943		return ret;
944	}
945	if (!nt->panel.backlight) {
946		struct backlight_device *bl;
947
948		bl = devm_backlight_device_register(dev, "nt35510", dev, nt,
949						    &nt35510_bl_ops, NULL);
950		if (IS_ERR(bl)) {
951			dev_err(dev, "failed to register backlight device\n");
952			return PTR_ERR(bl);
953		}
954		bl->props.max_brightness = 255;
955		bl->props.brightness = 255;
956		bl->props.power = FB_BLANK_POWERDOWN;
957		nt->panel.backlight = bl;
958	}
959
960	drm_panel_add(&nt->panel);
961
962	ret = mipi_dsi_attach(dsi);
963	if (ret < 0)
964		drm_panel_remove(&nt->panel);
965
966	return 0;
967}
968
969static void nt35510_remove(struct mipi_dsi_device *dsi)
970{
971	struct nt35510 *nt = mipi_dsi_get_drvdata(dsi);
972	int ret;
973
974	mipi_dsi_detach(dsi);
975	/* Power off */
976	ret = nt35510_power_off(nt);
977	if (ret)
978		dev_err(&dsi->dev, "Failed to power off\n");
979
980	drm_panel_remove(&nt->panel);
981}
982
983/*
984 * These gamma correction values are 10bit tuples, so only bits 0 and 1 is
985 * ever used in the first byte. They form a positive and negative gamma
986 * correction curve for each color, values must be strictly higher for each
987 * step on the curve. As can be seen these default curves goes from 0x0001
988 * to 0x03FE.
989 */
990#define NT35510_GAMMA_POS_DEFAULT 0x00, 0x01, 0x00, 0x43, 0x00, \
991		0x6B, 0x00, 0x87, 0x00, 0xA3, 0x00, 0xCE, 0x00, 0xF1, 0x01, \
992		0x27, 0x01, 0x53, 0x01, 0x98, 0x01, 0xCE, 0x02, 0x22, 0x02, \
993		0x83, 0x02, 0x78, 0x02, 0x9E, 0x02, 0xDD, 0x03, 0x00, 0x03, \
994		0x2E, 0x03, 0x54, 0x03, 0x7F, 0x03, 0x95, 0x03, 0xB3, 0x03, \
995		0xC2, 0x03, 0xE1, 0x03, 0xF1, 0x03, 0xFE
996
997#define NT35510_GAMMA_NEG_DEFAULT 0x00, 0x01, 0x00, 0x43, 0x00, \
998		0x6B, 0x00, 0x87, 0x00, 0xA3, 0x00, 0xCE, 0x00, 0xF1, 0x01, \
999		0x27, 0x01, 0x53, 0x01, 0x98, 0x01, 0xCE, 0x02, 0x22, 0x02, \
1000		0x43, 0x02, 0x50, 0x02, 0x9E, 0x02, 0xDD, 0x03, 0x00, 0x03, \
1001		0x2E, 0x03, 0x54, 0x03, 0x7F, 0x03, 0x95, 0x03, 0xB3, 0x03, \
1002		0xC2, 0x03, 0xE1, 0x03, 0xF1, 0x03, 0xFE
1003
1004/*
1005 * The Hydis HVA40WV1 panel
1006 */
1007static const struct nt35510_config nt35510_hydis_hva40wv1 = {
1008	.width_mm = 52,
1009	.height_mm = 86,
1010	/**
1011	 * As the Hydis panel is used in command mode, the porches etc
1012	 * are settings programmed internally into the NT35510 controller
1013	 * and generated toward the physical display. As the panel is not
1014	 * used in video mode, these are not really exposed to the DSI
1015	 * host.
1016	 *
1017	 * Display frame rate control:
1018	 * Frame rate = (20 MHz / 1) / (389 * (7 + 50 + 800)) ~= 60 Hz
1019	 */
1020	.mode = {
1021		/* The internal pixel clock of the NT35510 is 20 MHz */
1022		.clock = 20000,
1023		.hdisplay = 480,
1024		.hsync_start = 480 + 2, /* HFP = 2 */
1025		.hsync_end = 480 + 2 + 0, /* HSync = 0 */
1026		.htotal = 480 + 2 + 0 + 5, /* HFP = 5 */
1027		.vdisplay = 800,
1028		.vsync_start = 800 + 2, /* VFP = 2 */
1029		.vsync_end = 800 + 2 + 0, /* VSync = 0 */
1030		.vtotal = 800 + 2 + 0 + 5, /* VBP = 5 */
1031		.flags = 0,
1032	},
1033	/* 0x09: AVDD = 5.6V */
1034	.avdd = { 0x09, 0x09, 0x09 },
1035	/* 0x34: PCK = Hsync/2, BTP = 2 x VDDB */
1036	.bt1ctr = { 0x34, 0x34, 0x34 },
1037	/* 0x09: AVEE = -5.6V */
1038	.avee = { 0x09, 0x09, 0x09 },
1039	/* 0x24: NCK = Hsync/2, BTN =  -2 x VDDB */
1040	.bt2ctr = { 0x24, 0x24, 0x24 },
1041	/* 0x05 = 12V */
1042	.vgh = { 0x05, 0x05, 0x05 },
1043	/* 0x24: NCKA = Hsync/2, VGH = 2 x AVDD - AVEE */
1044	.bt4ctr = { 0x24, 0x24, 0x24 },
1045	/* 0x0B = -13V */
1046	.vgl = { 0x0B, 0x0B, 0x0B },
1047	/* 0x24: LCKA = Hsync, VGL = AVDD + VCL - AVDD */
1048	.bt5ctr = { 0x24, 0x24, 0x24 },
1049	/* VGMP: 0x0A3 = 5.0375V, VGSP = 0V */
1050	.vgp = { 0x00, 0xA3, 0x00 },
1051	/* VGMP: 0x0A3 = 5.0375V, VGSP = 0V */
1052	.vgn = { 0x00, 0xA3, 0x00 },
1053	/* SDEQCTR: source driver EQ mode 2, 2.5 us rise time on each step */
1054	.sdeqctr = { 0x01, 0x05, 0x05, 0x05 },
1055	/* SDVPCTR: Normal operation off color during v porch */
1056	.sdvpctr = 0x01,
1057	/* T1: number of pixel clocks on one scanline: 0x184 = 389 clocks */
1058	.t1 = 0x0184,
1059	/* VBP: vertical back porch toward the panel */
1060	.vbp = 7,
1061	/* VFP: vertical front porch toward the panel */
1062	.vfp = 50,
1063	/* PSEL: divide pixel clock 20MHz with 1 (no clock downscaling) */
1064	.psel = 0,
1065	/* DPTMCTR12: 0x03: LVGL = VGLX, overlap mode, swap R->L O->E */
1066	.dpmctr12 = { 0x03, 0x00, 0x00, },
1067	/* Default gamma correction values */
1068	.gamma_corr_pos_r = { NT35510_GAMMA_POS_DEFAULT },
1069	.gamma_corr_pos_g = { NT35510_GAMMA_POS_DEFAULT },
1070	.gamma_corr_pos_b = { NT35510_GAMMA_POS_DEFAULT },
1071	.gamma_corr_neg_r = { NT35510_GAMMA_NEG_DEFAULT },
1072	.gamma_corr_neg_g = { NT35510_GAMMA_NEG_DEFAULT },
1073	.gamma_corr_neg_b = { NT35510_GAMMA_NEG_DEFAULT },
1074};
1075
1076static const struct of_device_id nt35510_of_match[] = {
1077	{
1078		.compatible = "hydis,hva40wv1",
1079		.data = &nt35510_hydis_hva40wv1,
1080	},
1081	{ }
1082};
1083MODULE_DEVICE_TABLE(of, nt35510_of_match);
1084
1085static struct mipi_dsi_driver nt35510_driver = {
1086	.probe = nt35510_probe,
1087	.remove = nt35510_remove,
1088	.driver = {
1089		.name = "panel-novatek-nt35510",
1090		.of_match_table = nt35510_of_match,
1091	},
1092};
1093module_mipi_dsi_driver(nt35510_driver);
1094
1095MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
1096MODULE_DESCRIPTION("NT35510-based panel driver");
1097MODULE_LICENSE("GPL v2");
1098