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9#include <linux/backlight.h>
10#include <linux/delay.h>
11#include <linux/device.h>
12#include <linux/gpio/consumer.h>
13#include <linux/media-bus-format.h>
14#include <linux/module.h>
15#include <linux/of.h>
16#include <linux/of_device.h>
17#include <linux/regmap.h>
18#include <linux/regulator/consumer.h>
19#include <linux/spi/spi.h>
20
21#include <drm/drm_modes.h>
22#include <drm/drm_panel.h>
23
24enum nt39016_regs {
25 NT39016_REG_SYSTEM,
26 NT39016_REG_TIMING,
27 NT39016_REG_OP,
28 NT39016_REG_DATA_IN,
29 NT39016_REG_SRC_TIMING_DELAY,
30 NT39016_REG_GATE_TIMING_DELAY,
31 NT39016_REG_RESERVED,
32 NT39016_REG_INITIAL_FUNC,
33 NT39016_REG_CONTRAST,
34 NT39016_REG_BRIGHTNESS,
35 NT39016_REG_HUE_SATURATION,
36 NT39016_REG_RB_SUBCONTRAST,
37 NT39016_REG_R_SUBBRIGHTNESS,
38 NT39016_REG_B_SUBBRIGHTNESS,
39 NT39016_REG_VCOMDC,
40 NT39016_REG_VCOMAC,
41 NT39016_REG_VGAM2,
42 NT39016_REG_VGAM34,
43 NT39016_REG_VGAM56,
44 NT39016_REG_VCOMDC_TRIM = 0x1e,
45 NT39016_REG_DISPLAY_MODE = 0x20,
46};
47
48#define NT39016_SYSTEM_RESET_N BIT(0)
49#define NT39016_SYSTEM_STANDBY BIT(1)
50
51struct nt39016_panel_info {
52 struct drm_display_mode display_mode;
53 u16 width_mm, height_mm;
54 u32 bus_format, bus_flags;
55};
56
57struct nt39016 {
58 struct drm_panel drm_panel;
59 struct device *dev;
60 struct regmap *map;
61 struct regulator *supply;
62 const struct nt39016_panel_info *panel_info;
63
64 struct gpio_desc *reset_gpio;
65
66 struct backlight_device *backlight;
67};
68
69static inline struct nt39016 *to_nt39016(struct drm_panel *panel)
70{
71 return container_of(panel, struct nt39016, drm_panel);
72}
73
74#define RV(REG, VAL) { .reg = (REG), .def = (VAL), .delay_us = 2 }
75static const struct reg_sequence nt39016_panel_regs[] = {
76 RV(NT39016_REG_SYSTEM, 0x00),
77 RV(NT39016_REG_TIMING, 0x00),
78 RV(NT39016_REG_OP, 0x03),
79 RV(NT39016_REG_DATA_IN, 0xCC),
80 RV(NT39016_REG_SRC_TIMING_DELAY, 0x46),
81 RV(NT39016_REG_GATE_TIMING_DELAY, 0x05),
82 RV(NT39016_REG_RESERVED, 0x00),
83 RV(NT39016_REG_INITIAL_FUNC, 0x00),
84 RV(NT39016_REG_CONTRAST, 0x08),
85 RV(NT39016_REG_BRIGHTNESS, 0x40),
86 RV(NT39016_REG_HUE_SATURATION, 0x88),
87 RV(NT39016_REG_RB_SUBCONTRAST, 0x88),
88 RV(NT39016_REG_R_SUBBRIGHTNESS, 0x20),
89 RV(NT39016_REG_B_SUBBRIGHTNESS, 0x20),
90 RV(NT39016_REG_VCOMDC, 0x67),
91 RV(NT39016_REG_VCOMAC, 0xA4),
92 RV(NT39016_REG_VGAM2, 0x04),
93 RV(NT39016_REG_VGAM34, 0x24),
94 RV(NT39016_REG_VGAM56, 0x24),
95 RV(NT39016_REG_DISPLAY_MODE, 0x00),
96};
97
98#undef RV
99
100static const struct regmap_range nt39016_regmap_no_ranges[] = {
101 regmap_reg_range(0x13, 0x1D),
102 regmap_reg_range(0x1F, 0x1F),
103};
104
105static const struct regmap_access_table nt39016_regmap_access_table = {
106 .no_ranges = nt39016_regmap_no_ranges,
107 .n_no_ranges = ARRAY_SIZE(nt39016_regmap_no_ranges),
108};
109
110static const struct regmap_config nt39016_regmap_config = {
111 .reg_bits = 6,
112 .pad_bits = 2,
113 .val_bits = 8,
114
115 .max_register = NT39016_REG_DISPLAY_MODE,
116 .wr_table = &nt39016_regmap_access_table,
117 .write_flag_mask = 0x02,
118
119 .cache_type = REGCACHE_FLAT,
120};
121
122static int nt39016_prepare(struct drm_panel *drm_panel)
123{
124 struct nt39016 *panel = to_nt39016(drm_panel);
125 int err;
126
127 err = regulator_enable(panel->supply);
128 if (err) {
129 dev_err(panel->dev, "Failed to enable power supply: %d", err);
130 return err;
131 }
132
133
134
135
136
137
138
139 gpiod_set_value_cansleep(panel->reset_gpio, 1);
140 usleep_range(100, 1000);
141 gpiod_set_value_cansleep(panel->reset_gpio, 0);
142 udelay(2);
143
144
145 err = regmap_multi_reg_write(panel->map, nt39016_panel_regs,
146 ARRAY_SIZE(nt39016_panel_regs));
147 if (err) {
148 dev_err(panel->dev, "Failed to init registers: %d", err);
149 goto err_disable_regulator;
150 }
151
152 return 0;
153
154err_disable_regulator:
155 regulator_disable(panel->supply);
156 return err;
157}
158
159static int nt39016_unprepare(struct drm_panel *drm_panel)
160{
161 struct nt39016 *panel = to_nt39016(drm_panel);
162
163 gpiod_set_value_cansleep(panel->reset_gpio, 1);
164
165 regulator_disable(panel->supply);
166
167 return 0;
168}
169
170static int nt39016_enable(struct drm_panel *drm_panel)
171{
172 struct nt39016 *panel = to_nt39016(drm_panel);
173 int ret;
174
175 ret = regmap_write(panel->map, NT39016_REG_SYSTEM,
176 NT39016_SYSTEM_RESET_N | NT39016_SYSTEM_STANDBY);
177 if (ret) {
178 dev_err(panel->dev, "Unable to enable panel: %d", ret);
179 return ret;
180 }
181
182 if (panel->backlight) {
183
184 msleep(150);
185
186 ret = backlight_enable(panel->backlight);
187 }
188
189 return ret;
190}
191
192static int nt39016_disable(struct drm_panel *drm_panel)
193{
194 struct nt39016 *panel = to_nt39016(drm_panel);
195 int err;
196
197 backlight_disable(panel->backlight);
198
199 err = regmap_write(panel->map, NT39016_REG_SYSTEM,
200 NT39016_SYSTEM_RESET_N);
201 if (err) {
202 dev_err(panel->dev, "Unable to disable panel: %d", err);
203 return err;
204 }
205
206 return 0;
207}
208
209static int nt39016_get_modes(struct drm_panel *drm_panel)
210{
211 struct nt39016 *panel = to_nt39016(drm_panel);
212 const struct nt39016_panel_info *panel_info = panel->panel_info;
213 struct drm_connector *connector = drm_panel->connector;
214 struct drm_display_mode *mode;
215
216 mode = drm_mode_duplicate(drm_panel->drm, &panel_info->display_mode);
217 if (!mode)
218 return -ENOMEM;
219
220 drm_mode_set_name(mode);
221
222 mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
223 drm_mode_probed_add(connector, mode);
224
225 connector->display_info.bpc = 8;
226 connector->display_info.width_mm = panel_info->width_mm;
227 connector->display_info.height_mm = panel_info->height_mm;
228
229 drm_display_info_set_bus_formats(&connector->display_info,
230 &panel_info->bus_format, 1);
231 connector->display_info.bus_flags = panel_info->bus_flags;
232
233 return 1;
234}
235
236static const struct drm_panel_funcs nt39016_funcs = {
237 .prepare = nt39016_prepare,
238 .unprepare = nt39016_unprepare,
239 .enable = nt39016_enable,
240 .disable = nt39016_disable,
241 .get_modes = nt39016_get_modes,
242};
243
244static int nt39016_probe(struct spi_device *spi)
245{
246 struct device *dev = &spi->dev;
247 struct nt39016 *panel;
248 int err;
249
250 panel = devm_kzalloc(dev, sizeof(*panel), GFP_KERNEL);
251 if (!panel)
252 return -ENOMEM;
253
254 panel->dev = dev;
255 spi_set_drvdata(spi, panel);
256
257 panel->panel_info = of_device_get_match_data(dev);
258 if (!panel->panel_info)
259 return -EINVAL;
260
261 panel->supply = devm_regulator_get(dev, "power");
262 if (IS_ERR(panel->supply)) {
263 dev_err(dev, "Failed to get power supply");
264 return PTR_ERR(panel->supply);
265 }
266
267 panel->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
268 if (IS_ERR(panel->reset_gpio)) {
269 dev_err(dev, "Failed to get reset GPIO");
270 return PTR_ERR(panel->reset_gpio);
271 }
272
273 spi->bits_per_word = 8;
274 spi->mode = SPI_MODE_3 | SPI_3WIRE;
275 err = spi_setup(spi);
276 if (err) {
277 dev_err(dev, "Failed to setup SPI");
278 return err;
279 }
280
281 panel->map = devm_regmap_init_spi(spi, &nt39016_regmap_config);
282 if (IS_ERR(panel->map)) {
283 dev_err(dev, "Failed to init regmap");
284 return PTR_ERR(panel->map);
285 }
286
287 panel->backlight = devm_of_find_backlight(dev);
288 if (IS_ERR(panel->backlight)) {
289 err = PTR_ERR(panel->backlight);
290 if (err != -EPROBE_DEFER)
291 dev_err(dev, "Failed to get backlight handle");
292 return err;
293 }
294
295 drm_panel_init(&panel->drm_panel);
296 panel->drm_panel.dev = dev;
297 panel->drm_panel.funcs = &nt39016_funcs;
298
299 err = drm_panel_add(&panel->drm_panel);
300 if (err < 0) {
301 dev_err(dev, "Failed to register panel");
302 return err;
303 }
304
305 return 0;
306}
307
308static int nt39016_remove(struct spi_device *spi)
309{
310 struct nt39016 *panel = spi_get_drvdata(spi);
311
312 drm_panel_remove(&panel->drm_panel);
313
314 nt39016_disable(&panel->drm_panel);
315 nt39016_unprepare(&panel->drm_panel);
316
317 return 0;
318}
319
320static const struct nt39016_panel_info kd035g6_info = {
321 .display_mode = {
322 .clock = 6000,
323 .hdisplay = 320,
324 .hsync_start = 320 + 10,
325 .hsync_end = 320 + 10 + 50,
326 .htotal = 320 + 10 + 50 + 20,
327 .vdisplay = 240,
328 .vsync_start = 240 + 5,
329 .vsync_end = 240 + 5 + 1,
330 .vtotal = 240 + 5 + 1 + 4,
331 .vrefresh = 60,
332 .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
333 },
334 .width_mm = 71,
335 .height_mm = 53,
336 .bus_format = MEDIA_BUS_FMT_RGB888_1X24,
337 .bus_flags = DRM_BUS_FLAG_PIXDATA_NEGEDGE,
338};
339
340static const struct of_device_id nt39016_of_match[] = {
341 { .compatible = "kingdisplay,kd035g6-54nt", .data = &kd035g6_info },
342 { }
343};
344MODULE_DEVICE_TABLE(of, nt39016_of_match);
345
346static struct spi_driver nt39016_driver = {
347 .driver = {
348 .name = "nt39016",
349 .of_match_table = nt39016_of_match,
350 },
351 .probe = nt39016_probe,
352 .remove = nt39016_remove,
353};
354
355module_spi_driver(nt39016_driver);
356
357MODULE_AUTHOR("Maarten ter Huurne <maarten@treewalker.org>");
358MODULE_AUTHOR("Paul Cercueil <paul@crapouillou.net>");
359MODULE_LICENSE("GPL v2");
360
