1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2019, Amarula Solutions.
4 * Author: Jagan Teki <jagan@amarulasolutions.com>
5 */
6
7 #include <drm/drm_mipi_dsi.h>
8 #include <drm/drm_modes.h>
9 #include <drm/drm_panel.h>
10
11 #include <linux/gpio/consumer.h>
12 #include <linux/delay.h>
13 #include <linux/module.h>
14 #include <linux/of_device.h>
15 #include <linux/regulator/consumer.h>
16
17 #include <video/mipi_display.h>
18
19 /* Command2 BKx selection command */
20 #define DSI_CMD2BKX_SEL 0xFF
21
22 /* Command2, BK0 commands */
23 #define DSI_CMD2_BK0_PVGAMCTRL 0xB0 /* Positive Voltage Gamma Control */
24 #define DSI_CMD2_BK0_NVGAMCTRL 0xB1 /* Negative Voltage Gamma Control */
25 #define DSI_CMD2_BK0_LNESET 0xC0 /* Display Line setting */
26 #define DSI_CMD2_BK0_PORCTRL 0xC1 /* Porch control */
27 #define DSI_CMD2_BK0_INVSEL 0xC2 /* Inversion selection, Frame Rate Control */
28
29 /* Command2, BK1 commands */
30 #define DSI_CMD2_BK1_VRHS 0xB0 /* Vop amplitude setting */
31 #define DSI_CMD2_BK1_VCOM 0xB1 /* VCOM amplitude setting */
32 #define DSI_CMD2_BK1_VGHSS 0xB2 /* VGH Voltage setting */
33 #define DSI_CMD2_BK1_TESTCMD 0xB3 /* TEST Command Setting */
34 #define DSI_CMD2_BK1_VGLS 0xB5 /* VGL Voltage setting */
35 #define DSI_CMD2_BK1_PWCTLR1 0xB7 /* Power Control 1 */
36 #define DSI_CMD2_BK1_PWCTLR2 0xB8 /* Power Control 2 */
37 #define DSI_CMD2_BK1_SPD1 0xC1 /* Source pre_drive timing set1 */
38 #define DSI_CMD2_BK1_SPD2 0xC2 /* Source EQ2 Setting */
39 #define DSI_CMD2_BK1_MIPISET1 0xD0 /* MIPI Setting 1 */
40
41 /*
42 * Command2 with BK function selection.
43 *
44 * BIT[4, 0]: [CN2, BKXSEL]
45 * 10 = CMD2BK0, Command2 BK0
46 * 11 = CMD2BK1, Command2 BK1
47 * 00 = Command2 disable
48 */
49 #define DSI_CMD2BK1_SEL 0x11
50 #define DSI_CMD2BK0_SEL 0x10
51 #define DSI_CMD2BKX_SEL_NONE 0x00
52
53 /* Command2, BK0 bytes */
54 #define DSI_LINESET_LINE 0x69
55 #define DSI_LINESET_LDE_EN BIT(7)
56 #define DSI_LINESET_LINEDELTA GENMASK(1, 0)
57 #define DSI_CMD2_BK0_LNESET_B1 DSI_LINESET_LINEDELTA
58 #define DSI_CMD2_BK0_LNESET_B0 (DSI_LINESET_LDE_EN | DSI_LINESET_LINE)
59 #define DSI_INVSEL_DEFAULT GENMASK(5, 4)
60 #define DSI_INVSEL_NLINV GENMASK(2, 0)
61 #define DSI_INVSEL_RTNI GENMASK(2, 1)
62 #define DSI_CMD2_BK0_INVSEL_B1 DSI_INVSEL_RTNI
63 #define DSI_CMD2_BK0_INVSEL_B0 (DSI_INVSEL_DEFAULT | DSI_INVSEL_NLINV)
64 #define DSI_CMD2_BK0_PORCTRL_B0(m) ((m)->vtotal - (m)->vsync_end)
65 #define DSI_CMD2_BK0_PORCTRL_B1(m) ((m)->vsync_start - (m)->vdisplay)
66
67 /* Command2, BK1 bytes */
68 #define DSI_CMD2_BK1_VRHA_SET 0x45
69 #define DSI_CMD2_BK1_VCOM_SET 0x13
70 #define DSI_CMD2_BK1_VGHSS_SET GENMASK(2, 0)
71 #define DSI_CMD2_BK1_TESTCMD_VAL BIT(7)
72 #define DSI_VGLS_DEFAULT BIT(6)
73 #define DSI_VGLS_SEL GENMASK(2, 0)
74 #define DSI_CMD2_BK1_VGLS_SET (DSI_VGLS_DEFAULT | DSI_VGLS_SEL)
75 #define DSI_PWCTLR1_AP BIT(7) /* Gamma OP bias, max */
76 #define DSI_PWCTLR1_APIS BIT(2) /* Source OP input bias, min */
77 #define DSI_PWCTLR1_APOS BIT(0) /* Source OP output bias, min */
78 #define DSI_CMD2_BK1_PWCTLR1_SET (DSI_PWCTLR1_AP | DSI_PWCTLR1_APIS | \
79 DSI_PWCTLR1_APOS)
80 #define DSI_PWCTLR2_AVDD BIT(5) /* AVDD 6.6v */
81 #define DSI_PWCTLR2_AVCL 0x0 /* AVCL -4.4v */
82 #define DSI_CMD2_BK1_PWCTLR2_SET (DSI_PWCTLR2_AVDD | DSI_PWCTLR2_AVCL)
83 #define DSI_SPD1_T2D BIT(3)
84 #define DSI_CMD2_BK1_SPD1_SET (GENMASK(6, 4) | DSI_SPD1_T2D)
85 #define DSI_CMD2_BK1_SPD2_SET DSI_CMD2_BK1_SPD1_SET
86 #define DSI_MIPISET1_EOT_EN BIT(3)
87 #define DSI_CMD2_BK1_MIPISET1_SET (BIT(7) | DSI_MIPISET1_EOT_EN)
88
89 struct st7701_panel_desc {
90 const struct drm_display_mode *mode;
91 unsigned int lanes;
92 unsigned long flags;
93 enum mipi_dsi_pixel_format format;
94 const char *const *supply_names;
95 unsigned int num_supplies;
96 unsigned int panel_sleep_delay;
97 };
98
99 struct st7701 {
100 struct drm_panel panel;
101 struct mipi_dsi_device *dsi;
102 const struct st7701_panel_desc *desc;
103
104 struct regulator_bulk_data *supplies;
105 struct gpio_desc *reset;
106 unsigned int sleep_delay;
107 };
108
panel_to_st7701(struct drm_panel * panel)109 static inline struct st7701 *panel_to_st7701(struct drm_panel *panel)
110 {
111 return container_of(panel, struct st7701, panel);
112 }
113
st7701_dsi_write(struct st7701 * st7701,const void * seq,size_t len)114 static inline int st7701_dsi_write(struct st7701 *st7701, const void *seq,
115 size_t len)
116 {
117 return mipi_dsi_dcs_write_buffer(st7701->dsi, seq, len);
118 }
119
120 #define ST7701_DSI(st7701, seq...) \
121 { \
122 const u8 d[] = { seq }; \
123 st7701_dsi_write(st7701, d, ARRAY_SIZE(d)); \
124 }
125
st7701_init_sequence(struct st7701 * st7701)126 static void st7701_init_sequence(struct st7701 *st7701)
127 {
128 const struct drm_display_mode *mode = st7701->desc->mode;
129
130 ST7701_DSI(st7701, MIPI_DCS_SOFT_RESET, 0x00);
131
132 /* We need to wait 5ms before sending new commands */
133 msleep(5);
134
135 ST7701_DSI(st7701, MIPI_DCS_EXIT_SLEEP_MODE, 0x00);
136
137 msleep(st7701->sleep_delay);
138
139 /* Command2, BK0 */
140 ST7701_DSI(st7701, DSI_CMD2BKX_SEL,
141 0x77, 0x01, 0x00, 0x00, DSI_CMD2BK0_SEL);
142 ST7701_DSI(st7701, DSI_CMD2_BK0_PVGAMCTRL, 0x00, 0x0E, 0x15, 0x0F,
143 0x11, 0x08, 0x08, 0x08, 0x08, 0x23, 0x04, 0x13, 0x12,
144 0x2B, 0x34, 0x1F);
145 ST7701_DSI(st7701, DSI_CMD2_BK0_NVGAMCTRL, 0x00, 0x0E, 0x95, 0x0F,
146 0x13, 0x07, 0x09, 0x08, 0x08, 0x22, 0x04, 0x10, 0x0E,
147 0x2C, 0x34, 0x1F);
148 ST7701_DSI(st7701, DSI_CMD2_BK0_LNESET,
149 DSI_CMD2_BK0_LNESET_B0, DSI_CMD2_BK0_LNESET_B1);
150 ST7701_DSI(st7701, DSI_CMD2_BK0_PORCTRL,
151 DSI_CMD2_BK0_PORCTRL_B0(mode),
152 DSI_CMD2_BK0_PORCTRL_B1(mode));
153 ST7701_DSI(st7701, DSI_CMD2_BK0_INVSEL,
154 DSI_CMD2_BK0_INVSEL_B0, DSI_CMD2_BK0_INVSEL_B1);
155
156 /* Command2, BK1 */
157 ST7701_DSI(st7701, DSI_CMD2BKX_SEL,
158 0x77, 0x01, 0x00, 0x00, DSI_CMD2BK1_SEL);
159 ST7701_DSI(st7701, DSI_CMD2_BK1_VRHS, DSI_CMD2_BK1_VRHA_SET);
160 ST7701_DSI(st7701, DSI_CMD2_BK1_VCOM, DSI_CMD2_BK1_VCOM_SET);
161 ST7701_DSI(st7701, DSI_CMD2_BK1_VGHSS, DSI_CMD2_BK1_VGHSS_SET);
162 ST7701_DSI(st7701, DSI_CMD2_BK1_TESTCMD, DSI_CMD2_BK1_TESTCMD_VAL);
163 ST7701_DSI(st7701, DSI_CMD2_BK1_VGLS, DSI_CMD2_BK1_VGLS_SET);
164 ST7701_DSI(st7701, DSI_CMD2_BK1_PWCTLR1, DSI_CMD2_BK1_PWCTLR1_SET);
165 ST7701_DSI(st7701, DSI_CMD2_BK1_PWCTLR2, DSI_CMD2_BK1_PWCTLR2_SET);
166 ST7701_DSI(st7701, DSI_CMD2_BK1_SPD1, DSI_CMD2_BK1_SPD1_SET);
167 ST7701_DSI(st7701, DSI_CMD2_BK1_SPD2, DSI_CMD2_BK1_SPD2_SET);
168 ST7701_DSI(st7701, DSI_CMD2_BK1_MIPISET1, DSI_CMD2_BK1_MIPISET1_SET);
169
170 /**
171 * ST7701_SPEC_V1.2 is unable to provide enough information above this
172 * specific command sequence, so grab the same from vendor BSP driver.
173 */
174 ST7701_DSI(st7701, 0xE0, 0x00, 0x00, 0x02);
175 ST7701_DSI(st7701, 0xE1, 0x0B, 0x00, 0x0D, 0x00, 0x0C, 0x00, 0x0E,
176 0x00, 0x00, 0x44, 0x44);
177 ST7701_DSI(st7701, 0xE2, 0x33, 0x33, 0x44, 0x44, 0x64, 0x00, 0x66,
178 0x00, 0x65, 0x00, 0x67, 0x00, 0x00);
179 ST7701_DSI(st7701, 0xE3, 0x00, 0x00, 0x33, 0x33);
180 ST7701_DSI(st7701, 0xE4, 0x44, 0x44);
181 ST7701_DSI(st7701, 0xE5, 0x0C, 0x78, 0x3C, 0xA0, 0x0E, 0x78, 0x3C,
182 0xA0, 0x10, 0x78, 0x3C, 0xA0, 0x12, 0x78, 0x3C, 0xA0);
183 ST7701_DSI(st7701, 0xE6, 0x00, 0x00, 0x33, 0x33);
184 ST7701_DSI(st7701, 0xE7, 0x44, 0x44);
185 ST7701_DSI(st7701, 0xE8, 0x0D, 0x78, 0x3C, 0xA0, 0x0F, 0x78, 0x3C,
186 0xA0, 0x11, 0x78, 0x3C, 0xA0, 0x13, 0x78, 0x3C, 0xA0);
187 ST7701_DSI(st7701, 0xEB, 0x02, 0x02, 0x39, 0x39, 0xEE, 0x44, 0x00);
188 ST7701_DSI(st7701, 0xEC, 0x00, 0x00);
189 ST7701_DSI(st7701, 0xED, 0xFF, 0xF1, 0x04, 0x56, 0x72, 0x3F, 0xFF,
190 0xFF, 0xFF, 0xFF, 0xF3, 0x27, 0x65, 0x40, 0x1F, 0xFF);
191
192 /* disable Command2 */
193 ST7701_DSI(st7701, DSI_CMD2BKX_SEL,
194 0x77, 0x01, 0x00, 0x00, DSI_CMD2BKX_SEL_NONE);
195 }
196
st7701_prepare(struct drm_panel * panel)197 static int st7701_prepare(struct drm_panel *panel)
198 {
199 struct st7701 *st7701 = panel_to_st7701(panel);
200 int ret;
201
202 gpiod_set_value(st7701->reset, 0);
203
204 ret = regulator_bulk_enable(st7701->desc->num_supplies,
205 st7701->supplies);
206 if (ret < 0)
207 return ret;
208 msleep(20);
209
210 gpiod_set_value(st7701->reset, 1);
211 msleep(150);
212
213 st7701_init_sequence(st7701);
214
215 return 0;
216 }
217
st7701_enable(struct drm_panel * panel)218 static int st7701_enable(struct drm_panel *panel)
219 {
220 struct st7701 *st7701 = panel_to_st7701(panel);
221
222 ST7701_DSI(st7701, MIPI_DCS_SET_DISPLAY_ON, 0x00);
223
224 return 0;
225 }
226
st7701_disable(struct drm_panel * panel)227 static int st7701_disable(struct drm_panel *panel)
228 {
229 struct st7701 *st7701 = panel_to_st7701(panel);
230
231 ST7701_DSI(st7701, MIPI_DCS_SET_DISPLAY_OFF, 0x00);
232
233 return 0;
234 }
235
st7701_unprepare(struct drm_panel * panel)236 static int st7701_unprepare(struct drm_panel *panel)
237 {
238 struct st7701 *st7701 = panel_to_st7701(panel);
239
240 ST7701_DSI(st7701, MIPI_DCS_ENTER_SLEEP_MODE, 0x00);
241
242 msleep(st7701->sleep_delay);
243
244 gpiod_set_value(st7701->reset, 0);
245
246 /**
247 * During the Resetting period, the display will be blanked
248 * (The display is entering blanking sequence, which maximum
249 * time is 120 ms, when Reset Starts in Sleep Out –mode. The
250 * display remains the blank state in Sleep In –mode.) and
251 * then return to Default condition for Hardware Reset.
252 *
253 * So we need wait sleep_delay time to make sure reset completed.
254 */
255 msleep(st7701->sleep_delay);
256
257 regulator_bulk_disable(st7701->desc->num_supplies, st7701->supplies);
258
259 return 0;
260 }
261
st7701_get_modes(struct drm_panel * panel,struct drm_connector * connector)262 static int st7701_get_modes(struct drm_panel *panel,
263 struct drm_connector *connector)
264 {
265 struct st7701 *st7701 = panel_to_st7701(panel);
266 const struct drm_display_mode *desc_mode = st7701->desc->mode;
267 struct drm_display_mode *mode;
268
269 mode = drm_mode_duplicate(connector->dev, desc_mode);
270 if (!mode) {
271 dev_err(&st7701->dsi->dev, "failed to add mode %ux%u@%u\n",
272 desc_mode->hdisplay, desc_mode->vdisplay,
273 drm_mode_vrefresh(desc_mode));
274 return -ENOMEM;
275 }
276
277 drm_mode_set_name(mode);
278 drm_mode_probed_add(connector, mode);
279
280 connector->display_info.width_mm = desc_mode->width_mm;
281 connector->display_info.height_mm = desc_mode->height_mm;
282
283 return 1;
284 }
285
286 static const struct drm_panel_funcs st7701_funcs = {
287 .disable = st7701_disable,
288 .unprepare = st7701_unprepare,
289 .prepare = st7701_prepare,
290 .enable = st7701_enable,
291 .get_modes = st7701_get_modes,
292 };
293
294 static const struct drm_display_mode ts8550b_mode = {
295 .clock = 27500,
296
297 .hdisplay = 480,
298 .hsync_start = 480 + 38,
299 .hsync_end = 480 + 38 + 12,
300 .htotal = 480 + 38 + 12 + 12,
301
302 .vdisplay = 854,
303 .vsync_start = 854 + 18,
304 .vsync_end = 854 + 18 + 8,
305 .vtotal = 854 + 18 + 8 + 4,
306
307 .width_mm = 69,
308 .height_mm = 139,
309
310 .type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
311 };
312
313 static const char * const ts8550b_supply_names[] = {
314 "VCC",
315 "IOVCC",
316 };
317
318 static const struct st7701_panel_desc ts8550b_desc = {
319 .mode = &ts8550b_mode,
320 .lanes = 2,
321 .flags = MIPI_DSI_MODE_VIDEO,
322 .format = MIPI_DSI_FMT_RGB888,
323 .supply_names = ts8550b_supply_names,
324 .num_supplies = ARRAY_SIZE(ts8550b_supply_names),
325 .panel_sleep_delay = 80, /* panel need extra 80ms for sleep out cmd */
326 };
327
st7701_dsi_probe(struct mipi_dsi_device * dsi)328 static int st7701_dsi_probe(struct mipi_dsi_device *dsi)
329 {
330 const struct st7701_panel_desc *desc;
331 struct st7701 *st7701;
332 int ret, i;
333
334 st7701 = devm_kzalloc(&dsi->dev, sizeof(*st7701), GFP_KERNEL);
335 if (!st7701)
336 return -ENOMEM;
337
338 desc = of_device_get_match_data(&dsi->dev);
339 dsi->mode_flags = desc->flags;
340 dsi->format = desc->format;
341 dsi->lanes = desc->lanes;
342
343 st7701->supplies = devm_kcalloc(&dsi->dev, desc->num_supplies,
344 sizeof(*st7701->supplies),
345 GFP_KERNEL);
346 if (!st7701->supplies)
347 return -ENOMEM;
348
349 for (i = 0; i < desc->num_supplies; i++)
350 st7701->supplies[i].supply = desc->supply_names[i];
351
352 ret = devm_regulator_bulk_get(&dsi->dev, desc->num_supplies,
353 st7701->supplies);
354 if (ret < 0)
355 return ret;
356
357 st7701->reset = devm_gpiod_get(&dsi->dev, "reset", GPIOD_OUT_LOW);
358 if (IS_ERR(st7701->reset)) {
359 dev_err(&dsi->dev, "Couldn't get our reset GPIO\n");
360 return PTR_ERR(st7701->reset);
361 }
362
363 drm_panel_init(&st7701->panel, &dsi->dev, &st7701_funcs,
364 DRM_MODE_CONNECTOR_DSI);
365
366 /**
367 * Once sleep out has been issued, ST7701 IC required to wait 120ms
368 * before initiating new commands.
369 *
370 * On top of that some panels might need an extra delay to wait, so
371 * add panel specific delay for those cases. As now this panel specific
372 * delay information is referenced from those panel BSP driver, example
373 * ts8550b and there is no valid documentation for that.
374 */
375 st7701->sleep_delay = 120 + desc->panel_sleep_delay;
376
377 ret = drm_panel_of_backlight(&st7701->panel);
378 if (ret)
379 return ret;
380
381 drm_panel_add(&st7701->panel);
382
383 mipi_dsi_set_drvdata(dsi, st7701);
384 st7701->dsi = dsi;
385 st7701->desc = desc;
386
387 return mipi_dsi_attach(dsi);
388 }
389
st7701_dsi_remove(struct mipi_dsi_device * dsi)390 static int st7701_dsi_remove(struct mipi_dsi_device *dsi)
391 {
392 struct st7701 *st7701 = mipi_dsi_get_drvdata(dsi);
393
394 mipi_dsi_detach(dsi);
395 drm_panel_remove(&st7701->panel);
396
397 return 0;
398 }
399
400 static const struct of_device_id st7701_of_match[] = {
401 { .compatible = "techstar,ts8550b", .data = &ts8550b_desc },
402 { }
403 };
404 MODULE_DEVICE_TABLE(of, st7701_of_match);
405
406 static struct mipi_dsi_driver st7701_dsi_driver = {
407 .probe = st7701_dsi_probe,
408 .remove = st7701_dsi_remove,
409 .driver = {
410 .name = "st7701",
411 .of_match_table = st7701_of_match,
412 },
413 };
414 module_mipi_dsi_driver(st7701_dsi_driver);
415
416 MODULE_AUTHOR("Jagan Teki <jagan@amarulasolutions.com>");
417 MODULE_DESCRIPTION("Sitronix ST7701 LCD Panel Driver");
418 MODULE_LICENSE("GPL");
419