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 NT35510_CMD_CORRECT_GAMMA BIT(0)
40 #define NT35510_CMD_CONTROL_DISPLAY BIT(1)
41 
42 #define MCS_CMD_MAUCCTR		0xF0 /* Manufacturer command enable */
43 #define MCS_CMD_READ_ID1	0xDA
44 #define MCS_CMD_READ_ID2	0xDB
45 #define MCS_CMD_READ_ID3	0xDC
46 #define MCS_CMD_MTP_READ_SETTING 0xF8 /* Uncertain about name */
47 #define MCS_CMD_MTP_READ_PARAM 0xFF /* Uncertain about name */
48 
49 /*
50  * These manufacturer commands are available after we enable manufacturer
51  * command set (MCS) for page 0.
52  */
53 #define NT35510_P0_DOPCTR 0xB1
54 #define NT35510_P0_SDHDTCTR 0xB6
55 #define NT35510_P0_GSEQCTR 0xB7
56 #define NT35510_P0_SDEQCTR 0xB8
57 #define NT35510_P0_SDVPCTR 0xBA
58 #define NT35510_P0_DPFRCTR1 0xBD
59 #define NT35510_P0_DPFRCTR2 0xBE
60 #define NT35510_P0_DPFRCTR3 0xBF
61 #define NT35510_P0_DPMCTR12 0xCC
62 
63 #define NT35510_P0_DOPCTR_LEN 2
64 #define NT35510_P0_GSEQCTR_LEN 2
65 #define NT35510_P0_SDEQCTR_LEN 4
66 #define NT35510_P0_SDVPCTR_LEN 1
67 #define NT35510_P0_DPFRCTR1_LEN 5
68 #define NT35510_P0_DPFRCTR2_LEN 5
69 #define NT35510_P0_DPFRCTR3_LEN 5
70 #define NT35510_P0_DPMCTR12_LEN 3
71 
72 #define NT35510_DOPCTR_0_RAMKP BIT(7) /* Contents kept in sleep */
73 #define NT35510_DOPCTR_0_DSITE BIT(6) /* Enable TE signal */
74 #define NT35510_DOPCTR_0_DSIG BIT(5) /* Enable generic read/write */
75 #define NT35510_DOPCTR_0_DSIM BIT(4) /* Enable video mode on DSI */
76 #define NT35510_DOPCTR_0_EOTP BIT(3) /* Support EoTP */
77 #define NT35510_DOPCTR_0_N565 BIT(2) /* RGB or BGR pixel format */
78 #define NT35510_DOPCTR_1_TW_PWR_SEL BIT(4) /* TE power selector */
79 #define NT35510_DOPCTR_1_CRGB BIT(3) /* RGB or BGR byte order */
80 #define NT35510_DOPCTR_1_CTB BIT(2) /* Vertical scanning direction */
81 #define NT35510_DOPCTR_1_CRL BIT(1) /* Source driver data shift */
82 #define NT35510_P0_SDVPCTR_PRG BIT(2) /* 0 = normal operation, 1 = VGLO */
83 #define NT35510_P0_SDVPCTR_AVDD 0 /* source driver output = AVDD */
84 #define NT35510_P0_SDVPCTR_OFFCOL 1 /* source driver output = off color */
85 #define NT35510_P0_SDVPCTR_AVSS 2 /* source driver output = AVSS */
86 #define NT35510_P0_SDVPCTR_HI_Z 3 /* source driver output = High impedance */
87 
88 /*
89  * These manufacturer commands are available after we enable manufacturer
90  * command set (MCS) for page 1.
91  */
92 #define NT35510_P1_SETAVDD 0xB0
93 #define NT35510_P1_SETAVEE 0xB1
94 #define NT35510_P1_SETVCL 0xB2
95 #define NT35510_P1_SETVGH 0xB3
96 #define NT35510_P1_SETVRGH 0xB4
97 #define NT35510_P1_SETVGL 0xB5
98 #define NT35510_P1_BT1CTR 0xB6
99 #define NT35510_P1_BT2CTR 0xB7
100 #define NT35510_P1_BT3CTR 0xB8
101 #define NT35510_P1_BT4CTR 0xB9 /* VGH boosting times/freq */
102 #define NT35510_P1_BT5CTR 0xBA
103 #define NT35510_P1_PFMCTR 0xBB
104 #define NT35510_P1_SETVGP 0xBC
105 #define NT35510_P1_SETVGN 0xBD
106 #define NT35510_P1_SETVCMOFF 0xBE
107 #define NT35510_P1_VGHCTR 0xBF /* VGH output ctrl */
108 #define NT35510_P1_SET_GAMMA_RED_POS 0xD1
109 #define NT35510_P1_SET_GAMMA_GREEN_POS 0xD2
110 #define NT35510_P1_SET_GAMMA_BLUE_POS 0xD3
111 #define NT35510_P1_SET_GAMMA_RED_NEG 0xD4
112 #define NT35510_P1_SET_GAMMA_GREEN_NEG 0xD5
113 #define NT35510_P1_SET_GAMMA_BLUE_NEG 0xD6
114 
115 /* AVDD and AVEE setting 3 bytes */
116 #define NT35510_P1_AVDD_LEN 3
117 #define NT35510_P1_AVEE_LEN 3
118 #define NT35510_P1_VCL_LEN 3
119 #define NT35510_P1_VGH_LEN 3
120 #define NT35510_P1_VGL_LEN 3
121 #define NT35510_P1_VGP_LEN 3
122 #define NT35510_P1_VGN_LEN 3
123 #define NT35510_P1_VCMOFF_LEN 2
124 /* BT1CTR thru BT5CTR setting 3 bytes */
125 #define NT35510_P1_BT1CTR_LEN 3
126 #define NT35510_P1_BT2CTR_LEN 3
127 #define NT35510_P1_BT3CTR_LEN 3
128 #define NT35510_P1_BT4CTR_LEN 3
129 #define NT35510_P1_BT5CTR_LEN 3
130 /* 52 gamma parameters times two per color: positive and negative */
131 #define NT35510_P1_GAMMA_LEN 52
132 
133 #define NT35510_WRCTRLD_BCTRL BIT(5)
134 #define NT35510_WRCTRLD_A BIT(4)
135 #define NT35510_WRCTRLD_DD BIT(3)
136 #define NT35510_WRCTRLD_BL BIT(2)
137 #define NT35510_WRCTRLD_DB BIT(1)
138 #define NT35510_WRCTRLD_G BIT(0)
139 
140 #define NT35510_WRCABC_OFF 0
141 #define NT35510_WRCABC_UI_MODE 1
142 #define NT35510_WRCABC_STILL_MODE 2
143 #define NT35510_WRCABC_MOVING_MODE 3
144 
145 /**
146  * struct nt35510_config - the display-specific NT35510 configuration
147  *
148  * Some of the settings provide an array of bytes, A, B C which mean:
149  * A = normal / idle off mode
150  * B = idle on mode
151  * C = partial / idle off mode
152  *
153  * Gamma correction arrays are 10bit numbers, two consecutive bytes
154  * makes out one point on the gamma correction curve. The points are
155  * not linearly placed along the X axis, we get points 0, 1, 3, 5
156  * 7, 11, 15, 23, 31, 47, 63, 95, 127, 128, 160, 192, 208, 224, 232,
157  * 240, 244, 248, 250, 252, 254, 255. The voltages tuples form
158  * V0, V1, V3 ... V255, with 0x0000 being the lowest voltage and
159  * 0x03FF being the highest voltage.
160  *
161  * Each value must be strictly higher than the previous value forming
162  * a rising curve like this:
163  *
164  * ^
165  * |                                        V255
166  * |                                 V254
167  * |                         ....
168  * |                    V5
169  * |           V3
170  * |     V1
171  * | V0
172  * +------------------------------------------->
173  *
174  * The details about all settings can be found in the NT35510 Application
175  * Note.
176  */
177 struct nt35510_config {
178 	/**
179 	 * @width_mm: physical panel width [mm]
180 	 */
181 	u32 width_mm;
182 	/**
183 	 * @height_mm: physical panel height [mm]
184 	 */
185 	u32 height_mm;
186 	/**
187 	 * @mode: the display mode. This is only relevant outside the panel
188 	 * in video mode: in command mode this is configuring the internal
189 	 * timing in the display controller.
190 	 */
191 	const struct drm_display_mode mode;
192 	/**
193 	 * @mode_flags: DSI operation mode related flags
194 	 */
195 	unsigned long mode_flags;
196 	/**
197 	 * @cmds: enable DSI commands
198 	 */
199 	u32 cmds;
200 	/**
201 	 * @avdd: setting for AVDD ranging from 0x00 = 6.5V to 0x14 = 4.5V
202 	 * in 0.1V steps the default is 0x05 which means 6.0V
203 	 */
204 	u8 avdd[NT35510_P1_AVDD_LEN];
205 	/**
206 	 * @bt1ctr: setting for boost power control for the AVDD step-up
207 	 * circuit (1)
208 	 * bits 0..2 in the lower nibble controls PCK, the booster clock
209 	 * frequency for the step-up circuit:
210 	 * 0 = Hsync/32
211 	 * 1 = Hsync/16
212 	 * 2 = Hsync/8
213 	 * 3 = Hsync/4
214 	 * 4 = Hsync/2
215 	 * 5 = Hsync
216 	 * 6 = Hsync x 2
217 	 * 7 = Hsync x 4
218 	 * bits 4..6 in the upper nibble controls BTP, the boosting
219 	 * amplification for the step-up circuit:
220 	 * 0 = Disable
221 	 * 1 = 1.5 x VDDB
222 	 * 2 = 1.66 x VDDB
223 	 * 3 = 2 x VDDB
224 	 * 4 = 2.5 x VDDB
225 	 * 5 = 3 x VDDB
226 	 * The defaults are 4 and 4 yielding 0x44
227 	 */
228 	u8 bt1ctr[NT35510_P1_BT1CTR_LEN];
229 	/**
230 	 * @avee: setting for AVEE ranging from 0x00 = -6.5V to 0x14 = -4.5V
231 	 * in 0.1V steps the default is 0x05 which means -6.0V
232 	 */
233 	u8 avee[NT35510_P1_AVEE_LEN];
234 	/**
235 	 * @bt2ctr: setting for boost power control for the AVEE step-up
236 	 * circuit (2)
237 	 * bits 0..2 in the lower nibble controls NCK, the booster clock
238 	 * frequency, the values are the same as for PCK in @bt1ctr.
239 	 * bits 4..5 in the upper nibble controls BTN, the boosting
240 	 * amplification for the step-up circuit.
241 	 * 0 = Disable
242 	 * 1 = -1.5 x VDDB
243 	 * 2 = -2 x VDDB
244 	 * 3 = -2.5 x VDDB
245 	 * 4 = -3 x VDDB
246 	 * The defaults are 4 and 3 yielding 0x34
247 	 */
248 	u8 bt2ctr[NT35510_P1_BT2CTR_LEN];
249 	/**
250 	 * @vcl: setting for VCL ranging from 0x00 = -2.5V to 0x11 = -4.0V
251 	 * in 1V steps, the default is 0x00 which means -2.5V
252 	 */
253 	u8 vcl[NT35510_P1_VCL_LEN];
254 	/**
255 	 * @bt3ctr: setting for boost power control for the VCL step-up
256 	 * circuit (3)
257 	 * bits 0..2 in the lower nibble controls CLCK, the booster clock
258 	 * frequency, the values are the same as for PCK in @bt1ctr.
259 	 * bits 4..5 in the upper nibble controls BTCL, the boosting
260 	 * amplification for the step-up circuit.
261 	 * 0 = Disable
262 	 * 1 = -0.5 x VDDB
263 	 * 2 = -1 x VDDB
264 	 * 3 = -2 x VDDB
265 	 * The defaults are 4 and 2 yielding 0x24
266 	 */
267 	u8 bt3ctr[NT35510_P1_BT3CTR_LEN];
268 	/**
269 	 * @vgh: setting for VGH ranging from 0x00 = 7.0V to 0x0B = 18.0V
270 	 * in 1V steps, the default is 0x08 which means 15V
271 	 */
272 	u8 vgh[NT35510_P1_VGH_LEN];
273 	/**
274 	 * @bt4ctr: setting for boost power control for the VGH step-up
275 	 * circuit (4)
276 	 * bits 0..2 in the lower nibble controls HCK, the booster clock
277 	 * frequency, the values are the same as for PCK in @bt1ctr.
278 	 * bits 4..5 in the upper nibble controls BTH, the boosting
279 	 * amplification for the step-up circuit.
280 	 * 0 = AVDD + VDDB
281 	 * 1 = AVDD - AVEE
282 	 * 2 = AVDD - AVEE + VDDB
283 	 * 3 = AVDD x 2 - AVEE
284 	 * The defaults are 4 and 3 yielding 0x34
285 	 */
286 	u8 bt4ctr[NT35510_P1_BT4CTR_LEN];
287 	/**
288 	 * @vgl: setting for VGL ranging from 0x00 = -2V to 0x0f = -15V in
289 	 * 1V steps, the default is 0x08 which means -10V
290 	 */
291 	u8 vgl[NT35510_P1_VGL_LEN];
292 	/**
293 	 * @bt5ctr: setting for boost power control for the VGL step-up
294 	 * circuit (5)
295 	 * bits 0..2 in the lower nibble controls LCK, the booster clock
296 	 * frequency, the values are the same as for PCK in @bt1ctr.
297 	 * bits 4..5 in the upper nibble controls BTL, the boosting
298 	 * amplification for the step-up circuit.
299 	 * 0 = AVEE + VCL
300 	 * 1 = AVEE - AVDD
301 	 * 2 = AVEE + VCL - AVDD
302 	 * 3 = AVEE x 2 - AVDD
303 	 * The defaults are 3 and 2 yielding 0x32
304 	 */
305 	u8 bt5ctr[NT35510_P1_BT5CTR_LEN];
306 	/**
307 	 * @vgp: setting for VGP, the positive gamma divider voltages
308 	 * VGMP the high voltage and VGSP the low voltage.
309 	 * The first byte contains bit 8 of VGMP and VGSP in bits 4 and 0
310 	 * The second byte contains bit 0..7 of VGMP
311 	 * The third byte contains bit 0..7 of VGSP
312 	 * VGMP 0x00 = 3.0V .. 0x108 = 6.3V in steps of 12.5mV
313 	 * VGSP 0x00 = 0V .. 0x111 = 3.7V in steps of 12.5mV
314 	 */
315 	u8 vgp[NT35510_P1_VGP_LEN];
316 	/**
317 	 * @vgn: setting for VGN, the negative gamma divider voltages,
318 	 * same layout of bytes as @vgp.
319 	 */
320 	u8 vgn[NT35510_P1_VGN_LEN];
321 	/**
322 	 * @vcmoff: setting the DC VCOM offset voltage
323 	 * The first byte contains bit 8 of VCM in bit 0 and VCMOFFSEL in bit 4.
324 	 * The second byte contains bits 0..7 of VCM.
325 	 * VCMOFFSEL the common voltage offset mode.
326 	 * VCMOFFSEL 0x00 = VCOM .. 0x01 Gamma.
327 	 * The default is 0x00.
328 	 * VCM the VCOM output voltage (VCMOFFSEL = 0) or the internal register
329 	 * offset for gamma voltage (VCMOFFSEL = 1).
330 	 * VCM 0x00 = 0V/0 .. 0x118 = 3.5V/280 in steps of 12.5mV/1step
331 	 * The default is 0x00 = 0V/0.
332 	 */
333 	u8 vcmoff[NT35510_P1_VCMOFF_LEN];
334 	/**
335 	 * @dopctr: setting optional control for display
336 	 * ERR bits 0..1 in the first byte is the ERR pin output signal setting.
337 	 * 0 = Disable, ERR pin output low
338 	 * 1 = ERR pin output CRC error only
339 	 * 2 = ERR pin output ECC error only
340 	 * 3 = ERR pin output CRC and ECC error
341 	 * The default is 0.
342 	 * N565 bit 2 in the first byte is the 16-bit/pixel format selection.
343 	 * 0 = R[4:0] + G[5:3] & G[2:0] + B[4:0]
344 	 * 1 = G[2:0] + R[4:0] & B[4:0] + G[5:3]
345 	 * The default is 0.
346 	 * DIS_EoTP_HS bit 3 in the first byte is "DSI protocol violation" error
347 	 * reporting.
348 	 * 0 = reporting when error
349 	 * 1 = not reporting when error
350 	 * DSIM bit 4 in the first byte is the video mode data type enable
351 	 * 0 = Video mode data type disable
352 	 * 1 = Video mode data type enable
353 	 * The default is 0.
354 	 * DSIG bit 5 int the first byte is the generic r/w data type enable
355 	 * 0 = Generic r/w disable
356 	 * 1 = Generic r/w enable
357 	 * The default is 0.
358 	 * DSITE bit 6 in the first byte is TE line enable
359 	 * 0 = TE line is disabled
360 	 * 1 = TE line is enabled
361 	 * The default is 0.
362 	 * RAMKP bit 7 in the first byte is the frame memory keep/loss in
363 	 * sleep-in mode
364 	 * 0 = contents loss in sleep-in
365 	 * 1 = contents keep in sleep-in
366 	 * The default is 0.
367 	 * CRL bit 1 in the second byte is the source driver data shift
368 	 * direction selection. This bit is XOR operation with bit RSMX
369 	 * of 3600h command.
370 	 * 0 (RMSX = 0) = S1 -> S1440
371 	 * 0 (RMSX = 1) = S1440 -> S1
372 	 * 1 (RMSX = 0) = S1440 -> S1
373 	 * 1 (RMSX = 1) = S1 -> S1440
374 	 * The default is 0.
375 	 * CTB bit 2 in the second byte is the vertical scanning direction
376 	 * selection for gate control signals. This bit is XOR operation
377 	 * with bit ML of 3600h command.
378 	 * 0 (ML = 0) = Forward (top -> bottom)
379 	 * 0 (ML = 1) = Reverse (bottom -> top)
380 	 * 1 (ML = 0) = Reverse (bottom -> top)
381 	 * 1 (ML = 1) = Forward (top -> bottom)
382 	 * The default is 0.
383 	 * CRGB bit 3 in the second byte is RGB-BGR order selection. This
384 	 * bit is XOR operation with bit RGB of 3600h command.
385 	 * 0 (RGB = 0) = RGB/Normal
386 	 * 0 (RGB = 1) = BGR/RB swap
387 	 * 1 (RGB = 0) = BGR/RB swap
388 	 * 1 (RGB = 1) = RGB/Normal
389 	 * The default is 0.
390 	 * TE_PWR_SEL bit 4 in the second byte is the TE output voltage
391 	 * level selection (only valid when DSTB_SEL = 0 or DSTB_SEL = 1,
392 	 * VSEL = High and VDDI = 1.665~3.3V).
393 	 * 0 = TE output voltage level is VDDI
394 	 * 1 = TE output voltage level is VDDA
395 	 * The default is 0.
396 	 */
397 	u8 dopctr[NT35510_P0_DOPCTR_LEN];
398 	/**
399 	 * @madctl: Memory data access control
400 	 * RSMY bit 0 is flip vertical. Flips the display image top to down.
401 	 * RSMX bit 1 is flip horizontal. Flips the display image left to right.
402 	 * MH bit 2 is the horizontal refresh order.
403 	 * RGB bit 3 is the RGB-BGR order.
404 	 * 0 = RGB color sequence
405 	 * 1 = BGR color sequence
406 	 * ML bit 4 is the vertical refresh order.
407 	 * MV bit 5 is the row/column exchange.
408 	 * MX bit 6 is the column address order.
409 	 * MY bit 7 is the row address order.
410 	 */
411 	u8 madctl;
412 	/**
413 	 * @sdhdtctr: source output data hold time
414 	 * 0x00..0x3F = 0..31.5us in steps of 0.5us
415 	 * The default is 0x05 = 2.5us.
416 	 */
417 	u8 sdhdtctr;
418 	/**
419 	 * @gseqctr: EQ control for gate signals
420 	 * GFEQ_XX[3:0]: time setting of EQ step for falling edge in steps
421 	 * of 0.5us.
422 	 * The default is 0x07 = 3.5us
423 	 * GREQ_XX[7:4]: time setting of EQ step for rising edge in steps
424 	 * of 0.5us.
425 	 * The default is 0x07 = 3.5us
426 	 */
427 	u8 gseqctr[NT35510_P0_GSEQCTR_LEN];
428 	/**
429 	 * @sdeqctr: Source driver control settings, first byte is
430 	 * 0 for mode 1 and 1 for mode 2. Mode 1 uses two steps and
431 	 * mode 2 uses three steps meaning EQS3 is not used in mode
432 	 * 1. Mode 2 is default. The last three parameters are EQS1, EQS2
433 	 * and EQS3, setting the rise time for each equalizer step:
434 	 * 0x00 = 0.0 us to 0x0f = 7.5 us in steps of 0.5us. The default
435 	 * is 0x07 = 3.5 us.
436 	 */
437 	u8 sdeqctr[NT35510_P0_SDEQCTR_LEN];
438 	/**
439 	 * @sdvpctr: power/voltage behaviour during vertical porch time
440 	 */
441 	u8 sdvpctr;
442 	/**
443 	 * @t1: the number of pixel clocks on one scanline, range
444 	 * 0x100 (258 ticks) .. 0x3FF (1024 ticks) so the value + 1
445 	 * clock ticks.
446 	 */
447 	u16 t1;
448 	/**
449 	 * @vbp: vertical back porch toward the PANEL note: not toward
450 	 * the DSI host; these are separate interfaces, in from DSI host
451 	 * and out to the panel.
452 	 */
453 	u8 vbp;
454 	/**
455 	 * @vfp: vertical front porch toward the PANEL.
456 	 */
457 	u8 vfp;
458 	/**
459 	 * @psel: pixel clock divisor: 0 = 1, 1 = 2, 2 = 4, 3 = 8.
460 	 */
461 	u8 psel;
462 	/**
463 	 * @dpmctr12: Display timing control 12
464 	 * Byte 1 bit 4 selects LVGL voltage level: 0 = VGLX, 1 = VGL_REG
465 	 * Byte 1 bit 1 selects gate signal mode: 0 = non-overlap, 1 = overlap
466 	 * Byte 1 bit 0 selects output signal control R/L swap, 0 = normal
467 	 * 1 = swap all O->E, L->R
468 	 * Byte 2 is CLW delay clock for CK O/E and CKB O/E signals:
469 	 * 0x00 = 0us .. 0xFF = 12.75us in 0.05us steps
470 	 * Byte 3 is FTI_H0 delay time for STP O/E signals:
471 	 * 0x00 = 0us .. 0xFF = 12.75us in 0.05us steps
472 	 */
473 	u8 dpmctr12[NT35510_P0_DPMCTR12_LEN];
474 	/**
475 	 * @gamma_corr_pos_r: Red gamma correction parameters, positive
476 	 */
477 	u8 gamma_corr_pos_r[NT35510_P1_GAMMA_LEN];
478 	/**
479 	 * @gamma_corr_pos_g: Green gamma correction parameters, positive
480 	 */
481 	u8 gamma_corr_pos_g[NT35510_P1_GAMMA_LEN];
482 	/**
483 	 * @gamma_corr_pos_b: Blue gamma correction parameters, positive
484 	 */
485 	u8 gamma_corr_pos_b[NT35510_P1_GAMMA_LEN];
486 	/**
487 	 * @gamma_corr_neg_r: Red gamma correction parameters, negative
488 	 */
489 	u8 gamma_corr_neg_r[NT35510_P1_GAMMA_LEN];
490 	/**
491 	 * @gamma_corr_neg_g: Green gamma correction parameters, negative
492 	 */
493 	u8 gamma_corr_neg_g[NT35510_P1_GAMMA_LEN];
494 	/**
495 	 * @gamma_corr_neg_b: Blue gamma correction parameters, negative
496 	 */
497 	u8 gamma_corr_neg_b[NT35510_P1_GAMMA_LEN];
498 	/**
499 	 * @wrdisbv: write display brightness
500 	 * 0x00 value means the lowest brightness and 0xff value means
501 	 * the highest brightness.
502 	 * The default is 0x00.
503 	 */
504 	u8 wrdisbv;
505 	/**
506 	 * @wrctrld: write control display
507 	 * G bit 0 selects gamma curve: 0 = Manual, 1 = Automatic
508 	 * DB bit 1 selects display brightness: 0 = Manual, 1 = Automatic
509 	 * BL bit 2 controls backlight control: 0 = Off, 1 = On
510 	 * DD bit 3 controls display dimming: 0 = Off, 1 = On
511 	 * A bit 4 controls LABC block: 0 = Off, 1 = On
512 	 * BCTRL bit 5 controls brightness block: 0 = Off, 1 = On
513 	 */
514 	u8 wrctrld;
515 	/**
516 	 * @wrcabc: write content adaptive brightness control
517 	 * There is possible to use 4 different modes for content adaptive
518 	 * image functionality:
519 	 * 0: Off
520 	 * 1: User Interface Image (UI-Mode)
521 	 * 2: Still Picture Image (Still-Mode)
522 	 * 3: Moving Picture Image (Moving-Mode)
523 	 * The default is 0
524 	 */
525 	u8 wrcabc;
526 	/**
527 	 * @wrcabcmb: write CABC minimum brightness
528 	 * Set the minimum brightness value of the display for CABC
529 	 * function.
530 	 * 0x00 value means the lowest brightness for CABC and 0xff
531 	 * value means the highest brightness for CABC.
532 	 * The default is 0x00.
533 	 */
534 	u8 wrcabcmb;
535 };
536 
537 /**
538  * struct nt35510 - state container for the NT35510 panel
539  */
540 struct nt35510 {
541 	/**
542 	 * @dev: the container device
543 	 */
544 	struct device *dev;
545 	/**
546 	 * @conf: the specific panel configuration, as the NT35510
547 	 * can be combined with many physical panels, they can have
548 	 * different physical dimensions and gamma correction etc,
549 	 * so this is stored in the config.
550 	 */
551 	const struct nt35510_config *conf;
552 	/**
553 	 * @panel: the DRM panel object for the instance
554 	 */
555 	struct drm_panel panel;
556 	/**
557 	 * @supplies: regulators supplying the panel
558 	 */
559 	struct regulator_bulk_data supplies[2];
560 	/**
561 	 * @reset_gpio: the reset line
562 	 */
563 	struct gpio_desc *reset_gpio;
564 };
565 
566 /* Manufacturer command has strictly this byte sequence */
567 static const u8 nt35510_mauc_mtp_read_param[] = { 0xAA, 0x55, 0x25, 0x01 };
568 static const u8 nt35510_mauc_mtp_read_setting[] = { 0x01, 0x02, 0x00, 0x20,
569 						    0x33, 0x13, 0x00, 0x40,
570 						    0x00, 0x00, 0x23, 0x02 };
571 static const u8 nt35510_mauc_select_page_0[] = { 0x55, 0xAA, 0x52, 0x08, 0x00 };
572 static const u8 nt35510_mauc_select_page_1[] = { 0x55, 0xAA, 0x52, 0x08, 0x01 };
573 static const u8 nt35510_vgh_on[] = { 0x01 };
574 
panel_to_nt35510(struct drm_panel * panel)575 static inline struct nt35510 *panel_to_nt35510(struct drm_panel *panel)
576 {
577 	return container_of(panel, struct nt35510, panel);
578 }
579 
580 #define NT35510_ROTATE_0_SETTING	0x02
581 #define NT35510_ROTATE_180_SETTING	0x00
582 
nt35510_send_long(struct nt35510 * nt,struct mipi_dsi_device * dsi,u8 cmd,u8 cmdlen,const u8 * seq)583 static int nt35510_send_long(struct nt35510 *nt, struct mipi_dsi_device *dsi,
584 			     u8 cmd, u8 cmdlen, const u8 *seq)
585 {
586 	const u8 *seqp = seq;
587 	int cmdwritten = 0;
588 	int chunk = cmdlen;
589 	int ret;
590 
591 	if (chunk > 15)
592 		chunk = 15;
593 	ret = mipi_dsi_dcs_write(dsi, cmd, seqp, chunk);
594 	if (ret < 0) {
595 		dev_err(nt->dev, "error sending DCS command seq cmd %02x\n", cmd);
596 		return ret;
597 	}
598 	cmdwritten += chunk;
599 	seqp += chunk;
600 
601 	while (cmdwritten < cmdlen) {
602 		chunk = cmdlen - cmdwritten;
603 		if (chunk > 15)
604 			chunk = 15;
605 		ret = mipi_dsi_generic_write(dsi, seqp, chunk);
606 		if (ret < 0) {
607 			dev_err(nt->dev, "error sending generic write seq %02x\n", cmd);
608 			return ret;
609 		}
610 		cmdwritten += chunk;
611 		seqp += chunk;
612 	}
613 	dev_dbg(nt->dev, "sent command %02x %02x bytes\n", cmd, cmdlen);
614 	return 0;
615 }
616 
nt35510_read_id(struct nt35510 * nt)617 static int nt35510_read_id(struct nt35510 *nt)
618 {
619 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
620 	u8 id1, id2, id3;
621 	int ret;
622 
623 	ret = mipi_dsi_dcs_read(dsi, MCS_CMD_READ_ID1, &id1, 1);
624 	if (ret < 0) {
625 		dev_err(nt->dev, "could not read MTP ID1\n");
626 		return ret;
627 	}
628 	ret = mipi_dsi_dcs_read(dsi, MCS_CMD_READ_ID2, &id2, 1);
629 	if (ret < 0) {
630 		dev_err(nt->dev, "could not read MTP ID2\n");
631 		return ret;
632 	}
633 	ret = mipi_dsi_dcs_read(dsi, MCS_CMD_READ_ID3, &id3, 1);
634 	if (ret < 0) {
635 		dev_err(nt->dev, "could not read MTP ID3\n");
636 		return ret;
637 	}
638 
639 	/*
640 	 * Multi-Time Programmable (?) memory contains manufacturer
641 	 * ID (e.g. Hydis 0x55), driver ID (e.g. NT35510 0xc0) and
642 	 * version.
643 	 */
644 	dev_info(nt->dev, "MTP ID manufacturer: %02x version: %02x driver: %02x\n", id1, id2, id3);
645 
646 	return 0;
647 }
648 
649 /**
650  * nt35510_setup_power() - set up power config in page 1
651  * @nt: the display instance to set up
652  */
nt35510_setup_power(struct nt35510 * nt)653 static int nt35510_setup_power(struct nt35510 *nt)
654 {
655 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
656 	int ret;
657 
658 	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETAVDD,
659 				NT35510_P1_AVDD_LEN,
660 				nt->conf->avdd);
661 	if (ret)
662 		return ret;
663 	ret = nt35510_send_long(nt, dsi, NT35510_P1_BT1CTR,
664 				NT35510_P1_BT1CTR_LEN,
665 				nt->conf->bt1ctr);
666 	if (ret)
667 		return ret;
668 	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETAVEE,
669 				NT35510_P1_AVEE_LEN,
670 				nt->conf->avee);
671 	if (ret)
672 		return ret;
673 	ret = nt35510_send_long(nt, dsi, NT35510_P1_BT2CTR,
674 				NT35510_P1_BT2CTR_LEN,
675 				nt->conf->bt2ctr);
676 	if (ret)
677 		return ret;
678 	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETVCL,
679 				NT35510_P1_VCL_LEN,
680 				nt->conf->vcl);
681 	if (ret)
682 		return ret;
683 	ret = nt35510_send_long(nt, dsi, NT35510_P1_BT3CTR,
684 				NT35510_P1_BT3CTR_LEN,
685 				nt->conf->bt3ctr);
686 	if (ret)
687 		return ret;
688 	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETVGH,
689 				NT35510_P1_VGH_LEN,
690 				nt->conf->vgh);
691 	if (ret)
692 		return ret;
693 	ret = nt35510_send_long(nt, dsi, NT35510_P1_BT4CTR,
694 				NT35510_P1_BT4CTR_LEN,
695 				nt->conf->bt4ctr);
696 	if (ret)
697 		return ret;
698 	ret = nt35510_send_long(nt, dsi, NT35510_P1_VGHCTR,
699 				ARRAY_SIZE(nt35510_vgh_on),
700 				nt35510_vgh_on);
701 	if (ret)
702 		return ret;
703 	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETVGL,
704 				NT35510_P1_VGL_LEN,
705 				nt->conf->vgl);
706 	if (ret)
707 		return ret;
708 	ret = nt35510_send_long(nt, dsi, NT35510_P1_BT5CTR,
709 				NT35510_P1_BT5CTR_LEN,
710 				nt->conf->bt5ctr);
711 	if (ret)
712 		return ret;
713 	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETVGP,
714 				NT35510_P1_VGP_LEN,
715 				nt->conf->vgp);
716 	if (ret)
717 		return ret;
718 	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETVGN,
719 				NT35510_P1_VGN_LEN,
720 				nt->conf->vgn);
721 	if (ret)
722 		return ret;
723 
724 	ret = nt35510_send_long(nt, dsi, NT35510_P1_SETVCMOFF,
725 				NT35510_P1_VCMOFF_LEN,
726 				nt->conf->vcmoff);
727 	if (ret)
728 		return ret;
729 
730 	/* Typically 10 ms */
731 	usleep_range(10000, 20000);
732 
733 	return 0;
734 }
735 
736 /**
737  * nt35510_setup_display() - set up display config in page 0
738  * @nt: the display instance to set up
739  */
nt35510_setup_display(struct nt35510 * nt)740 static int nt35510_setup_display(struct nt35510 *nt)
741 {
742 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
743 	const struct nt35510_config *conf = nt->conf;
744 	u8 dpfrctr[NT35510_P0_DPFRCTR1_LEN];
745 	int ret;
746 
747 	ret = nt35510_send_long(nt, dsi, NT35510_P0_DOPCTR,
748 				NT35510_P0_DOPCTR_LEN,
749 				conf->dopctr);
750 	if (ret)
751 		return ret;
752 
753 	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_ADDRESS_MODE, &conf->madctl,
754 				 sizeof(conf->madctl));
755 	if (ret < 0)
756 		return ret;
757 
758 	ret = mipi_dsi_dcs_write(dsi, NT35510_P0_SDHDTCTR, &conf->sdhdtctr,
759 				 sizeof(conf->sdhdtctr));
760 	if (ret < 0)
761 		return ret;
762 
763 	ret = nt35510_send_long(nt, dsi, NT35510_P0_GSEQCTR,
764 				NT35510_P0_GSEQCTR_LEN,
765 				conf->gseqctr);
766 	if (ret)
767 		return ret;
768 
769 	ret = nt35510_send_long(nt, dsi, NT35510_P0_SDEQCTR,
770 				NT35510_P0_SDEQCTR_LEN,
771 				conf->sdeqctr);
772 	if (ret)
773 		return ret;
774 
775 	ret = mipi_dsi_dcs_write(dsi, NT35510_P0_SDVPCTR,
776 				 &conf->sdvpctr, 1);
777 	if (ret < 0)
778 		return ret;
779 
780 	/*
781 	 * Display timing control for active and idle off mode:
782 	 * the first byte contains
783 	 * the two high bits of T1A and second byte the low 8 bits, and
784 	 * the valid range is 0x100 (257) to 0x3ff (1023) representing
785 	 * 258..1024 (+1) pixel clock ticks for one scanline. At 20MHz pixel
786 	 * clock this covers the range of 12.90us .. 51.20us in steps of
787 	 * 0.05us, the default is 0x184 (388) representing 389 ticks.
788 	 * The third byte is VBPDA, vertical back porch display active
789 	 * and the fourth VFPDA, vertical front porch display active,
790 	 * both given in number of scanlines in the range 0x02..0xff
791 	 * for 2..255 scanlines. The fifth byte is 2 bits selecting
792 	 * PSEL for active and idle off mode, how much the 20MHz clock
793 	 * is divided by 0..3.  This needs to be adjusted to get the right
794 	 * frame rate.
795 	 */
796 	dpfrctr[0] = (conf->t1 >> 8) & 0xFF;
797 	dpfrctr[1] = conf->t1 & 0xFF;
798 	/* Vertical back porch */
799 	dpfrctr[2] = conf->vbp;
800 	/* Vertical front porch */
801 	dpfrctr[3] = conf->vfp;
802 	dpfrctr[4] = conf->psel;
803 	ret = nt35510_send_long(nt, dsi, NT35510_P0_DPFRCTR1,
804 				NT35510_P0_DPFRCTR1_LEN,
805 				dpfrctr);
806 	if (ret)
807 		return ret;
808 	/* For idle and partial idle off mode we decrease front porch by one */
809 	dpfrctr[3]--;
810 	ret = nt35510_send_long(nt, dsi, NT35510_P0_DPFRCTR2,
811 				NT35510_P0_DPFRCTR2_LEN,
812 				dpfrctr);
813 	if (ret)
814 		return ret;
815 	ret = nt35510_send_long(nt, dsi, NT35510_P0_DPFRCTR3,
816 				NT35510_P0_DPFRCTR3_LEN,
817 				dpfrctr);
818 	if (ret)
819 		return ret;
820 
821 	/* Enable TE on vblank */
822 	ret = mipi_dsi_dcs_set_tear_on(dsi, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
823 	if (ret)
824 		return ret;
825 
826 	/* Turn on the pads? */
827 	ret = nt35510_send_long(nt, dsi, NT35510_P0_DPMCTR12,
828 				NT35510_P0_DPMCTR12_LEN,
829 				conf->dpmctr12);
830 	if (ret)
831 		return ret;
832 
833 	return 0;
834 }
835 
nt35510_set_brightness(struct backlight_device * bl)836 static int nt35510_set_brightness(struct backlight_device *bl)
837 {
838 	struct nt35510 *nt = bl_get_data(bl);
839 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
840 	u8 brightness = bl->props.brightness;
841 	int ret;
842 
843 	dev_dbg(nt->dev, "set brightness %d\n", brightness);
844 	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
845 				 &brightness,
846 				 sizeof(brightness));
847 	if (ret < 0)
848 		return ret;
849 
850 	return 0;
851 }
852 
853 static const struct backlight_ops nt35510_bl_ops = {
854 	.update_status = nt35510_set_brightness,
855 };
856 
857 /*
858  * This power-on sequence
859  */
nt35510_power_on(struct nt35510 * nt)860 static int nt35510_power_on(struct nt35510 *nt)
861 {
862 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
863 	int ret;
864 
865 	ret = regulator_bulk_enable(ARRAY_SIZE(nt->supplies), nt->supplies);
866 	if (ret < 0) {
867 		dev_err(nt->dev, "unable to enable regulators\n");
868 		return ret;
869 	}
870 
871 	/* Toggle RESET in accordance with datasheet page 370 */
872 	if (nt->reset_gpio) {
873 		gpiod_set_value(nt->reset_gpio, 1);
874 		/* Active min 10 us according to datasheet, let's say 20 */
875 		usleep_range(20, 1000);
876 		gpiod_set_value(nt->reset_gpio, 0);
877 		/*
878 		 * 5 ms during sleep mode, 120 ms during sleep out mode
879 		 * according to datasheet, let's use 120-140 ms.
880 		 */
881 		usleep_range(120000, 140000);
882 	}
883 
884 	ret = nt35510_send_long(nt, dsi, MCS_CMD_MTP_READ_PARAM,
885 				ARRAY_SIZE(nt35510_mauc_mtp_read_param),
886 				nt35510_mauc_mtp_read_param);
887 	if (ret)
888 		return ret;
889 
890 	ret = nt35510_send_long(nt, dsi, MCS_CMD_MTP_READ_SETTING,
891 				ARRAY_SIZE(nt35510_mauc_mtp_read_setting),
892 				nt35510_mauc_mtp_read_setting);
893 	if (ret)
894 		return ret;
895 
896 	nt35510_read_id(nt);
897 
898 	/* Set up stuff in  manufacturer control, page 1 */
899 	ret = nt35510_send_long(nt, dsi, MCS_CMD_MAUCCTR,
900 				ARRAY_SIZE(nt35510_mauc_select_page_1),
901 				nt35510_mauc_select_page_1);
902 	if (ret)
903 		return ret;
904 
905 	ret = nt35510_setup_power(nt);
906 	if (ret)
907 		return ret;
908 
909 	if (nt->conf->cmds & NT35510_CMD_CORRECT_GAMMA) {
910 		ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_RED_POS,
911 					NT35510_P1_GAMMA_LEN,
912 					nt->conf->gamma_corr_pos_r);
913 		if (ret)
914 			return ret;
915 		ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_GREEN_POS,
916 					NT35510_P1_GAMMA_LEN,
917 					nt->conf->gamma_corr_pos_g);
918 		if (ret)
919 			return ret;
920 		ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_BLUE_POS,
921 					NT35510_P1_GAMMA_LEN,
922 					nt->conf->gamma_corr_pos_b);
923 		if (ret)
924 			return ret;
925 		ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_RED_NEG,
926 					NT35510_P1_GAMMA_LEN,
927 					nt->conf->gamma_corr_neg_r);
928 		if (ret)
929 			return ret;
930 		ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_GREEN_NEG,
931 					NT35510_P1_GAMMA_LEN,
932 					nt->conf->gamma_corr_neg_g);
933 		if (ret)
934 			return ret;
935 		ret = nt35510_send_long(nt, dsi, NT35510_P1_SET_GAMMA_BLUE_NEG,
936 					NT35510_P1_GAMMA_LEN,
937 					nt->conf->gamma_corr_neg_b);
938 		if (ret)
939 			return ret;
940 	}
941 
942 	/* Set up stuff in  manufacturer control, page 0 */
943 	ret = nt35510_send_long(nt, dsi, MCS_CMD_MAUCCTR,
944 				ARRAY_SIZE(nt35510_mauc_select_page_0),
945 				nt35510_mauc_select_page_0);
946 	if (ret)
947 		return ret;
948 
949 	ret = nt35510_setup_display(nt);
950 	if (ret)
951 		return ret;
952 
953 	return 0;
954 }
955 
nt35510_power_off(struct nt35510 * nt)956 static int nt35510_power_off(struct nt35510 *nt)
957 {
958 	int ret;
959 
960 	ret = regulator_bulk_disable(ARRAY_SIZE(nt->supplies), nt->supplies);
961 	if (ret)
962 		return ret;
963 
964 	if (nt->reset_gpio)
965 		gpiod_set_value(nt->reset_gpio, 1);
966 
967 	return 0;
968 }
969 
nt35510_unprepare(struct drm_panel * panel)970 static int nt35510_unprepare(struct drm_panel *panel)
971 {
972 	struct nt35510 *nt = panel_to_nt35510(panel);
973 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
974 	int ret;
975 
976 	ret = mipi_dsi_dcs_set_display_off(dsi);
977 	if (ret) {
978 		dev_err(nt->dev, "failed to turn display off (%d)\n", ret);
979 		return ret;
980 	}
981 	usleep_range(10000, 20000);
982 
983 	/* Enter sleep mode */
984 	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
985 	if (ret) {
986 		dev_err(nt->dev, "failed to enter sleep mode (%d)\n", ret);
987 		return ret;
988 	}
989 
990 	/* Wait 4 frames, how much is that 5ms in the vendor driver */
991 	usleep_range(5000, 10000);
992 
993 	ret = nt35510_power_off(nt);
994 	if (ret)
995 		return ret;
996 
997 	return 0;
998 }
999 
nt35510_prepare(struct drm_panel * panel)1000 static int nt35510_prepare(struct drm_panel *panel)
1001 {
1002 	struct nt35510 *nt = panel_to_nt35510(panel);
1003 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
1004 	int ret;
1005 
1006 	ret = nt35510_power_on(nt);
1007 	if (ret)
1008 		return ret;
1009 
1010 	/* Exit sleep mode */
1011 	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
1012 	if (ret) {
1013 		dev_err(nt->dev, "failed to exit sleep mode (%d)\n", ret);
1014 		return ret;
1015 	}
1016 	/* Up to 120 ms */
1017 	usleep_range(120000, 150000);
1018 
1019 	if (nt->conf->cmds & NT35510_CMD_CONTROL_DISPLAY) {
1020 		ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
1021 					 &nt->conf->wrctrld,
1022 					 sizeof(nt->conf->wrctrld));
1023 		if (ret < 0)
1024 			return ret;
1025 
1026 		ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_POWER_SAVE,
1027 					 &nt->conf->wrcabc,
1028 					 sizeof(nt->conf->wrcabc));
1029 		if (ret < 0)
1030 			return ret;
1031 
1032 		ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_CABC_MIN_BRIGHTNESS,
1033 					 &nt->conf->wrcabcmb,
1034 					 sizeof(nt->conf->wrcabcmb));
1035 		if (ret < 0)
1036 			return ret;
1037 	}
1038 
1039 	ret = mipi_dsi_dcs_set_display_on(dsi);
1040 	if (ret) {
1041 		dev_err(nt->dev, "failed to turn display on (%d)\n", ret);
1042 		return ret;
1043 	}
1044 	/* Some 10 ms */
1045 	usleep_range(10000, 20000);
1046 
1047 	return 0;
1048 }
1049 
nt35510_get_modes(struct drm_panel * panel,struct drm_connector * connector)1050 static int nt35510_get_modes(struct drm_panel *panel,
1051 			     struct drm_connector *connector)
1052 {
1053 	struct nt35510 *nt = panel_to_nt35510(panel);
1054 	struct drm_display_mode *mode;
1055 	struct drm_display_info *info;
1056 
1057 	info = &connector->display_info;
1058 	info->width_mm = nt->conf->width_mm;
1059 	info->height_mm = nt->conf->height_mm;
1060 	mode = drm_mode_duplicate(connector->dev, &nt->conf->mode);
1061 	if (!mode) {
1062 		dev_err(panel->dev, "bad mode or failed to add mode\n");
1063 		return -EINVAL;
1064 	}
1065 	drm_mode_set_name(mode);
1066 	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
1067 
1068 	mode->width_mm = nt->conf->width_mm;
1069 	mode->height_mm = nt->conf->height_mm;
1070 	drm_mode_probed_add(connector, mode);
1071 
1072 	return 1; /* Number of modes */
1073 }
1074 
1075 static const struct drm_panel_funcs nt35510_drm_funcs = {
1076 	.unprepare = nt35510_unprepare,
1077 	.prepare = nt35510_prepare,
1078 	.get_modes = nt35510_get_modes,
1079 };
1080 
nt35510_probe(struct mipi_dsi_device * dsi)1081 static int nt35510_probe(struct mipi_dsi_device *dsi)
1082 {
1083 	struct device *dev = &dsi->dev;
1084 	struct nt35510 *nt;
1085 	int ret;
1086 
1087 	nt = devm_kzalloc(dev, sizeof(struct nt35510), GFP_KERNEL);
1088 	if (!nt)
1089 		return -ENOMEM;
1090 	mipi_dsi_set_drvdata(dsi, nt);
1091 	nt->dev = dev;
1092 
1093 	dsi->lanes = 2;
1094 	dsi->format = MIPI_DSI_FMT_RGB888;
1095 	/*
1096 	 * Datasheet suggests max HS rate for NT35510 is 250 MHz
1097 	 * (period time 4ns, see figure 7.6.4 page 365) and max LP rate is
1098 	 * 20 MHz (period time 50ns, see figure 7.6.6. page 366).
1099 	 * However these frequencies appear in source code for the Hydis
1100 	 * HVA40WV1 panel and setting up the LP frequency makes the panel
1101 	 * not work.
1102 	 *
1103 	 * TODO: if other panels prove to be closer to the datasheet,
1104 	 * maybe make this a per-panel config in struct nt35510_config?
1105 	 */
1106 	dsi->hs_rate = 349440000;
1107 	dsi->lp_rate = 9600000;
1108 
1109 	/*
1110 	 * Every new incarnation of this display must have a unique
1111 	 * data entry for the system in this driver.
1112 	 */
1113 	nt->conf = of_device_get_match_data(dev);
1114 	if (!nt->conf) {
1115 		dev_err(dev, "missing device configuration\n");
1116 		return -ENODEV;
1117 	}
1118 
1119 	dsi->mode_flags = nt->conf->mode_flags;
1120 
1121 	nt->supplies[0].supply = "vdd"; /* 2.3-4.8 V */
1122 	nt->supplies[1].supply = "vddi"; /* 1.65-3.3V */
1123 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(nt->supplies),
1124 				      nt->supplies);
1125 	if (ret < 0)
1126 		return ret;
1127 	ret = regulator_set_voltage(nt->supplies[0].consumer,
1128 				    2300000, 4800000);
1129 	if (ret)
1130 		return ret;
1131 	ret = regulator_set_voltage(nt->supplies[1].consumer,
1132 				    1650000, 3300000);
1133 	if (ret)
1134 		return ret;
1135 
1136 	nt->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
1137 	if (IS_ERR(nt->reset_gpio)) {
1138 		dev_err(dev, "error getting RESET GPIO\n");
1139 		return PTR_ERR(nt->reset_gpio);
1140 	}
1141 
1142 	drm_panel_init(&nt->panel, dev, &nt35510_drm_funcs,
1143 		       DRM_MODE_CONNECTOR_DSI);
1144 
1145 	/*
1146 	 * First, try to locate an external backlight (such as on GPIO)
1147 	 * if this fails, assume we will want to use the internal backlight
1148 	 * control.
1149 	 */
1150 	ret = drm_panel_of_backlight(&nt->panel);
1151 	if (ret) {
1152 		dev_err(dev, "error getting external backlight %d\n", ret);
1153 		return ret;
1154 	}
1155 	if (!nt->panel.backlight) {
1156 		struct backlight_device *bl;
1157 
1158 		bl = devm_backlight_device_register(dev, "nt35510", dev, nt,
1159 						    &nt35510_bl_ops, NULL);
1160 		if (IS_ERR(bl)) {
1161 			dev_err(dev, "failed to register backlight device\n");
1162 			return PTR_ERR(bl);
1163 		}
1164 		bl->props.max_brightness = 255;
1165 		if (nt->conf->cmds & NT35510_CMD_CONTROL_DISPLAY)
1166 			bl->props.brightness = nt->conf->wrdisbv;
1167 		else
1168 			bl->props.brightness = 255;
1169 		bl->props.power = BACKLIGHT_POWER_OFF;
1170 		nt->panel.backlight = bl;
1171 	}
1172 
1173 	drm_panel_add(&nt->panel);
1174 
1175 	ret = mipi_dsi_attach(dsi);
1176 	if (ret < 0)
1177 		drm_panel_remove(&nt->panel);
1178 
1179 	return 0;
1180 }
1181 
nt35510_remove(struct mipi_dsi_device * dsi)1182 static void nt35510_remove(struct mipi_dsi_device *dsi)
1183 {
1184 	struct nt35510 *nt = mipi_dsi_get_drvdata(dsi);
1185 	int ret;
1186 
1187 	mipi_dsi_detach(dsi);
1188 	/* Power off */
1189 	ret = nt35510_power_off(nt);
1190 	if (ret)
1191 		dev_err(&dsi->dev, "Failed to power off\n");
1192 
1193 	drm_panel_remove(&nt->panel);
1194 }
1195 
1196 /*
1197  * These gamma correction values are 10bit tuples, so only bits 0 and 1 is
1198  * ever used in the first byte. They form a positive and negative gamma
1199  * correction curve for each color, values must be strictly higher for each
1200  * step on the curve. As can be seen these default curves goes from 0x0001
1201  * to 0x03FE.
1202  */
1203 #define NT35510_GAMMA_POS_DEFAULT 0x00, 0x01, 0x00, 0x43, 0x00, \
1204 		0x6B, 0x00, 0x87, 0x00, 0xA3, 0x00, 0xCE, 0x00, 0xF1, 0x01, \
1205 		0x27, 0x01, 0x53, 0x01, 0x98, 0x01, 0xCE, 0x02, 0x22, 0x02, \
1206 		0x83, 0x02, 0x78, 0x02, 0x9E, 0x02, 0xDD, 0x03, 0x00, 0x03, \
1207 		0x2E, 0x03, 0x54, 0x03, 0x7F, 0x03, 0x95, 0x03, 0xB3, 0x03, \
1208 		0xC2, 0x03, 0xE1, 0x03, 0xF1, 0x03, 0xFE
1209 
1210 #define NT35510_GAMMA_NEG_DEFAULT 0x00, 0x01, 0x00, 0x43, 0x00, \
1211 		0x6B, 0x00, 0x87, 0x00, 0xA3, 0x00, 0xCE, 0x00, 0xF1, 0x01, \
1212 		0x27, 0x01, 0x53, 0x01, 0x98, 0x01, 0xCE, 0x02, 0x22, 0x02, \
1213 		0x43, 0x02, 0x50, 0x02, 0x9E, 0x02, 0xDD, 0x03, 0x00, 0x03, \
1214 		0x2E, 0x03, 0x54, 0x03, 0x7F, 0x03, 0x95, 0x03, 0xB3, 0x03, \
1215 		0xC2, 0x03, 0xE1, 0x03, 0xF1, 0x03, 0xFE
1216 
1217 /*
1218  * The Hydis HVA40WV1 panel
1219  */
1220 static const struct nt35510_config nt35510_hydis_hva40wv1 = {
1221 	.width_mm = 52,
1222 	.height_mm = 86,
1223 	/**
1224 	 * As the Hydis panel is used in command mode, the porches etc
1225 	 * are settings programmed internally into the NT35510 controller
1226 	 * and generated toward the physical display. As the panel is not
1227 	 * used in video mode, these are not really exposed to the DSI
1228 	 * host.
1229 	 *
1230 	 * Display frame rate control:
1231 	 * Frame rate = (20 MHz / 1) / (389 * (7 + 50 + 800)) ~= 60 Hz
1232 	 */
1233 	.mode = {
1234 		/* The internal pixel clock of the NT35510 is 20 MHz */
1235 		.clock = 20000,
1236 		.hdisplay = 480,
1237 		.hsync_start = 480 + 2, /* HFP = 2 */
1238 		.hsync_end = 480 + 2 + 0, /* HSync = 0 */
1239 		.htotal = 480 + 2 + 0 + 5, /* HBP = 5 */
1240 		.vdisplay = 800,
1241 		.vsync_start = 800 + 2, /* VFP = 2 */
1242 		.vsync_end = 800 + 2 + 0, /* VSync = 0 */
1243 		.vtotal = 800 + 2 + 0 + 5, /* VBP = 5 */
1244 		.flags = 0,
1245 	},
1246 	.mode_flags = MIPI_DSI_CLOCK_NON_CONTINUOUS,
1247 	.cmds = NT35510_CMD_CORRECT_GAMMA,
1248 	/* 0x09: AVDD = 5.6V */
1249 	.avdd = { 0x09, 0x09, 0x09 },
1250 	/* 0x34: PCK = Hsync/2, BTP = 2 x VDDB */
1251 	.bt1ctr = { 0x34, 0x34, 0x34 },
1252 	/* 0x09: AVEE = -5.6V */
1253 	.avee = { 0x09, 0x09, 0x09 },
1254 	/* 0x24: NCK = Hsync/2, BTN =  -2 x VDDB */
1255 	.bt2ctr = { 0x24, 0x24, 0x24 },
1256 	/* VBCLA: -2.5V, VBCLB: -2.5V, VBCLC: -2.5V */
1257 	.vcl = { 0x00, 0x00, 0x00 },
1258 	/* 0x24: CLCK = Hsync/2, BTN =  -1 x VDDB */
1259 	.bt3ctr = { 0x24, 0x24, 0x24 },
1260 	/* 0x05 = 12V */
1261 	.vgh = { 0x05, 0x05, 0x05 },
1262 	/* 0x24: NCKA = Hsync/2, VGH = 2 x AVDD - AVEE */
1263 	.bt4ctr = { 0x24, 0x24, 0x24 },
1264 	/* 0x0B = -13V */
1265 	.vgl = { 0x0B, 0x0B, 0x0B },
1266 	/* 0x24: LCKA = Hsync, VGL = AVDD + VCL - AVDD */
1267 	.bt5ctr = { 0x24, 0x24, 0x24 },
1268 	/* VGMP: 0x0A3 = 5.0375V, VGSP = 0V */
1269 	.vgp = { 0x00, 0xA3, 0x00 },
1270 	/* VGMP: 0x0A3 = 5.0375V, VGSP = 0V */
1271 	.vgn = { 0x00, 0xA3, 0x00 },
1272 	/* VCMOFFSEL = VCOM voltage offset mode, VCM = 0V */
1273 	.vcmoff = { 0x00, 0x00 },
1274 	/* Enable TE, EoTP and RGB pixel format */
1275 	.dopctr = { NT35510_DOPCTR_0_DSITE | NT35510_DOPCTR_0_EOTP |
1276 		    NT35510_DOPCTR_0_N565, NT35510_DOPCTR_1_CTB },
1277 	.madctl = NT35510_ROTATE_0_SETTING,
1278 	/* 0x0A: SDT = 5 us */
1279 	.sdhdtctr = 0x0A,
1280 	/* EQ control for gate signals, 0x00 = 0 us */
1281 	.gseqctr = { 0x00, 0x00 },
1282 	/* SDEQCTR: source driver EQ mode 2, 2.5 us rise time on each step */
1283 	.sdeqctr = { 0x01, 0x05, 0x05, 0x05 },
1284 	/* SDVPCTR: Normal operation off color during v porch */
1285 	.sdvpctr = 0x01,
1286 	/* T1: number of pixel clocks on one scanline: 0x184 = 389 clocks */
1287 	.t1 = 0x0184,
1288 	/* VBP: vertical back porch toward the panel */
1289 	.vbp = 7,
1290 	/* VFP: vertical front porch toward the panel */
1291 	.vfp = 50,
1292 	/* PSEL: divide pixel clock 20MHz with 1 (no clock downscaling) */
1293 	.psel = 0,
1294 	/* DPTMCTR12: 0x03: LVGL = VGLX, overlap mode, swap R->L O->E */
1295 	.dpmctr12 = { 0x03, 0x00, 0x00, },
1296 	/* Default gamma correction values */
1297 	.gamma_corr_pos_r = { NT35510_GAMMA_POS_DEFAULT },
1298 	.gamma_corr_pos_g = { NT35510_GAMMA_POS_DEFAULT },
1299 	.gamma_corr_pos_b = { NT35510_GAMMA_POS_DEFAULT },
1300 	.gamma_corr_neg_r = { NT35510_GAMMA_NEG_DEFAULT },
1301 	.gamma_corr_neg_g = { NT35510_GAMMA_NEG_DEFAULT },
1302 	.gamma_corr_neg_b = { NT35510_GAMMA_NEG_DEFAULT },
1303 };
1304 
1305 static const struct nt35510_config nt35510_frida_frd400b25025 = {
1306 	.width_mm = 52,
1307 	.height_mm = 86,
1308 	.mode = {
1309 		.clock = 23000,
1310 		.hdisplay = 480,
1311 		.hsync_start = 480 + 34, /* HFP = 34 */
1312 		.hsync_end = 480 + 34 + 2, /* HSync = 2 */
1313 		.htotal = 480 + 34 + 2 + 34, /* HBP = 34 */
1314 		.vdisplay = 800,
1315 		.vsync_start = 800 + 15, /* VFP = 15 */
1316 		.vsync_end = 800 + 15 + 12, /* VSync = 12 */
1317 		.vtotal = 800 + 15 + 12 + 15, /* VBP = 15 */
1318 		.flags = 0,
1319 	},
1320 	.mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
1321 			MIPI_DSI_MODE_LPM,
1322 	.cmds = NT35510_CMD_CONTROL_DISPLAY,
1323 	/* 0x03: AVDD = 6.2V */
1324 	.avdd = { 0x03, 0x03, 0x03 },
1325 	/* 0x46: PCK = 2 x Hsync, BTP = 2.5 x VDDB */
1326 	.bt1ctr = { 0x46, 0x46, 0x46 },
1327 	/* 0x03: AVEE = -6.2V */
1328 	.avee = { 0x03, 0x03, 0x03 },
1329 	/* 0x36: PCK = 2 x Hsync, BTP =  2 x VDDB */
1330 	.bt2ctr = { 0x36, 0x36, 0x36 },
1331 	/* VBCLA: -2.5V, VBCLB: -2.5V, VBCLC: -3.5V */
1332 	.vcl = { 0x00, 0x00, 0x02 },
1333 	/* 0x26: CLCK = 2 x Hsync, BTN =  -1 x VDDB */
1334 	.bt3ctr = { 0x26, 0x26, 0x26 },
1335 	/* 0x09 = 16V */
1336 	.vgh = { 0x09, 0x09, 0x09 },
1337 	/* 0x36: HCK = 2 x Hsync, VGH = 2 x AVDD - AVEE */
1338 	.bt4ctr = { 0x36, 0x36, 0x36 },
1339 	/* 0x08 = -10V */
1340 	.vgl = { 0x08, 0x08, 0x08 },
1341 	/* 0x26: LCK = 2 x Hsync, VGL = AVDD + VCL - AVDD */
1342 	.bt5ctr = { 0x26, 0x26, 0x26 },
1343 	/* VGMP: 0x080 = 4.6V, VGSP = 0V */
1344 	.vgp = { 0x00, 0x80, 0x00 },
1345 	/* VGMP: 0x080 = 4.6V, VGSP = 0V */
1346 	.vgn = { 0x00, 0x80, 0x00 },
1347 	/* VCMOFFSEL = VCOM voltage offset mode, VCM = -1V */
1348 	.vcmoff = { 0x00, 0x50 },
1349 	.dopctr = { NT35510_DOPCTR_0_RAMKP | NT35510_DOPCTR_0_DSITE |
1350 		NT35510_DOPCTR_0_DSIG | NT35510_DOPCTR_0_DSIM |
1351 		NT35510_DOPCTR_0_EOTP | NT35510_DOPCTR_0_N565, 0 },
1352 	.madctl = NT35510_ROTATE_180_SETTING,
1353 	/* 0x03: SDT = 1.5 us */
1354 	.sdhdtctr = 0x03,
1355 	/* EQ control for gate signals, 0x00 = 0 us */
1356 	.gseqctr = { 0x00, 0x00 },
1357 	/* SDEQCTR: source driver EQ mode 2, 1 us rise time on each step */
1358 	.sdeqctr = { 0x01, 0x02, 0x02, 0x02 },
1359 	/* SDVPCTR: Normal operation off color during v porch */
1360 	.sdvpctr = 0x01,
1361 	/* T1: number of pixel clocks on one scanline: 0x184 = 389 clocks */
1362 	.t1 = 0x0184,
1363 	/* VBP: vertical back porch toward the panel */
1364 	.vbp = 0x1C,
1365 	/* VFP: vertical front porch toward the panel */
1366 	.vfp = 0x1C,
1367 	/* PSEL: divide pixel clock 23MHz with 1 (no clock downscaling) */
1368 	.psel = 0,
1369 	/* DPTMCTR12: 0x03: LVGL = VGLX, overlap mode, swap R->L O->E */
1370 	.dpmctr12 = { 0x03, 0x00, 0x00, },
1371 	/* write display brightness */
1372 	.wrdisbv = 0x7f,
1373 	/* write control display */
1374 	.wrctrld = NT35510_WRCTRLD_BCTRL | NT35510_WRCTRLD_DD |
1375 			NT35510_WRCTRLD_BL,
1376 	/* write content adaptive brightness control */
1377 	.wrcabc = NT35510_WRCABC_STILL_MODE,
1378 	/* write CABC minimum brightness */
1379 	.wrcabcmb = 0xff,
1380 };
1381 
1382 static const struct of_device_id nt35510_of_match[] = {
1383 	{
1384 		.compatible = "frida,frd400b25025",
1385 		.data = &nt35510_frida_frd400b25025,
1386 	},
1387 	{
1388 		.compatible = "hydis,hva40wv1",
1389 		.data = &nt35510_hydis_hva40wv1,
1390 	},
1391 	{ }
1392 };
1393 MODULE_DEVICE_TABLE(of, nt35510_of_match);
1394 
1395 static struct mipi_dsi_driver nt35510_driver = {
1396 	.probe = nt35510_probe,
1397 	.remove = nt35510_remove,
1398 	.driver = {
1399 		.name = "panel-novatek-nt35510",
1400 		.of_match_table = nt35510_of_match,
1401 	},
1402 };
1403 module_mipi_dsi_driver(nt35510_driver);
1404 
1405 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
1406 MODULE_DESCRIPTION("NT35510-based panel driver");
1407 MODULE_LICENSE("GPL v2");
1408