1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2014 NVIDIA Corporation
  4 */
  5
  6#include <linux/backlight.h>
  7#include <linux/delay.h>
  8#include <linux/gpio/consumer.h>
  9#include <linux/module.h>
 10#include <linux/of.h>
 11#include <linux/regulator/consumer.h>
 12
 13#include <video/mipi_display.h>
 14
 15#include <drm/drm_crtc.h>
 16#include <drm/drm_device.h>
 17#include <drm/drm_mipi_dsi.h>
 18#include <drm/drm_panel.h>
 19
 20struct sharp_panel {
 21	struct drm_panel base;
 22	/* the datasheet refers to them as DSI-LINK1 and DSI-LINK2 */
 23	struct mipi_dsi_device *link1;
 24	struct mipi_dsi_device *link2;
 25
 26	struct backlight_device *backlight;
 27	struct regulator *supply;
 28
 29	bool prepared;
 30	bool enabled;
 31
 32	const struct drm_display_mode *mode;
 33};
 34
 35static inline struct sharp_panel *to_sharp_panel(struct drm_panel *panel)
 36{
 37	return container_of(panel, struct sharp_panel, base);
 38}
 39
 40static void sharp_wait_frames(struct sharp_panel *sharp, unsigned int frames)
 41{
 42	unsigned int refresh = drm_mode_vrefresh(sharp->mode);
 43
 44	if (WARN_ON(frames > refresh))
 45		return;
 46
 47	msleep(1000 / (refresh / frames));
 48}
 49
 50static int sharp_panel_write(struct sharp_panel *sharp, u16 offset, u8 value)
 51{
 52	u8 payload[3] = { offset >> 8, offset & 0xff, value };
 53	struct mipi_dsi_device *dsi = sharp->link1;
 54	ssize_t err;
 55
 56	err = mipi_dsi_generic_write(dsi, payload, sizeof(payload));
 57	if (err < 0) {
 58		dev_err(&dsi->dev, "failed to write %02x to %04x: %zd\n",
 59			value, offset, err);
 60		return err;
 61	}
 62
 63	err = mipi_dsi_dcs_nop(dsi);
 64	if (err < 0) {
 65		dev_err(&dsi->dev, "failed to send DCS nop: %zd\n", err);
 66		return err;
 67	}
 68
 69	usleep_range(10, 20);
 70
 71	return 0;
 72}
 73
 74static __maybe_unused int sharp_panel_read(struct sharp_panel *sharp,
 75					   u16 offset, u8 *value)
 76{
 77	ssize_t err;
 78
 79	cpu_to_be16s(&offset);
 80
 81	err = mipi_dsi_generic_read(sharp->link1, &offset, sizeof(offset),
 82				    value, sizeof(*value));
 83	if (err < 0)
 84		dev_err(&sharp->link1->dev, "failed to read from %04x: %zd\n",
 85			offset, err);
 86
 87	return err;
 88}
 89
 90static int sharp_panel_disable(struct drm_panel *panel)
 91{
 92	struct sharp_panel *sharp = to_sharp_panel(panel);
 93
 94	if (!sharp->enabled)
 95		return 0;
 96
 97	backlight_disable(sharp->backlight);
 98
 99	sharp->enabled = false;
100
101	return 0;
102}
103
104static int sharp_panel_unprepare(struct drm_panel *panel)
105{
106	struct sharp_panel *sharp = to_sharp_panel(panel);
107	int err;
108
109	if (!sharp->prepared)
110		return 0;
111
112	sharp_wait_frames(sharp, 4);
113
114	err = mipi_dsi_dcs_set_display_off(sharp->link1);
115	if (err < 0)
116		dev_err(panel->dev, "failed to set display off: %d\n", err);
117
118	err = mipi_dsi_dcs_enter_sleep_mode(sharp->link1);
119	if (err < 0)
120		dev_err(panel->dev, "failed to enter sleep mode: %d\n", err);
121
122	msleep(120);
123
124	regulator_disable(sharp->supply);
125
126	sharp->prepared = false;
127
128	return 0;
129}
130
131static int sharp_setup_symmetrical_split(struct mipi_dsi_device *left,
132					 struct mipi_dsi_device *right,
133					 const struct drm_display_mode *mode)
134{
135	int err;
136
137	err = mipi_dsi_dcs_set_column_address(left, 0, mode->hdisplay / 2 - 1);
138	if (err < 0) {
139		dev_err(&left->dev, "failed to set column address: %d\n", err);
140		return err;
141	}
142
143	err = mipi_dsi_dcs_set_page_address(left, 0, mode->vdisplay - 1);
144	if (err < 0) {
145		dev_err(&left->dev, "failed to set page address: %d\n", err);
146		return err;
147	}
148
149	err = mipi_dsi_dcs_set_column_address(right, mode->hdisplay / 2,
150					      mode->hdisplay - 1);
151	if (err < 0) {
152		dev_err(&right->dev, "failed to set column address: %d\n", err);
153		return err;
154	}
155
156	err = mipi_dsi_dcs_set_page_address(right, 0, mode->vdisplay - 1);
157	if (err < 0) {
158		dev_err(&right->dev, "failed to set page address: %d\n", err);
159		return err;
160	}
161
162	return 0;
163}
164
165static int sharp_panel_prepare(struct drm_panel *panel)
166{
167	struct sharp_panel *sharp = to_sharp_panel(panel);
168	u8 format = MIPI_DCS_PIXEL_FMT_24BIT;
169	int err;
170
171	if (sharp->prepared)
172		return 0;
173
174	err = regulator_enable(sharp->supply);
175	if (err < 0)
176		return err;
177
178	/*
179	 * According to the datasheet, the panel needs around 10 ms to fully
180	 * power up. At least another 120 ms is required before exiting sleep
181	 * mode to make sure the panel is ready. Throw in another 20 ms for
182	 * good measure.
183	 */
184	msleep(150);
185
186	err = mipi_dsi_dcs_exit_sleep_mode(sharp->link1);
187	if (err < 0) {
188		dev_err(panel->dev, "failed to exit sleep mode: %d\n", err);
189		goto poweroff;
190	}
191
192	/*
193	 * The MIPI DCS specification mandates this delay only between the
194	 * exit_sleep_mode and enter_sleep_mode commands, so it isn't strictly
195	 * necessary here.
196	 */
197	/*
198	msleep(120);
199	*/
200
201	/* set left-right mode */
202	err = sharp_panel_write(sharp, 0x1000, 0x2a);
203	if (err < 0) {
204		dev_err(panel->dev, "failed to set left-right mode: %d\n", err);
205		goto poweroff;
206	}
207
208	/* enable command mode */
209	err = sharp_panel_write(sharp, 0x1001, 0x01);
210	if (err < 0) {
211		dev_err(panel->dev, "failed to enable command mode: %d\n", err);
212		goto poweroff;
213	}
214
215	err = mipi_dsi_dcs_set_pixel_format(sharp->link1, format);
216	if (err < 0) {
217		dev_err(panel->dev, "failed to set pixel format: %d\n", err);
218		goto poweroff;
219	}
220
221	/*
222	 * TODO: The device supports both left-right and even-odd split
223	 * configurations, but this driver currently supports only the left-
224	 * right split. To support a different mode a mechanism needs to be
225	 * put in place to communicate the configuration back to the DSI host
226	 * controller.
227	 */
228	err = sharp_setup_symmetrical_split(sharp->link1, sharp->link2,
229					    sharp->mode);
230	if (err < 0) {
231		dev_err(panel->dev, "failed to set up symmetrical split: %d\n",
232			err);
233		goto poweroff;
234	}
235
236	err = mipi_dsi_dcs_set_display_on(sharp->link1);
237	if (err < 0) {
238		dev_err(panel->dev, "failed to set display on: %d\n", err);
239		goto poweroff;
240	}
241
242	sharp->prepared = true;
243
244	/* wait for 6 frames before continuing */
245	sharp_wait_frames(sharp, 6);
246
247	return 0;
248
249poweroff:
250	regulator_disable(sharp->supply);
251	return err;
252}
253
254static int sharp_panel_enable(struct drm_panel *panel)
255{
256	struct sharp_panel *sharp = to_sharp_panel(panel);
257
258	if (sharp->enabled)
259		return 0;
260
261	backlight_enable(sharp->backlight);
262
263	sharp->enabled = true;
264
265	return 0;
266}
267
268static const struct drm_display_mode default_mode = {
269	.clock = 278000,
270	.hdisplay = 2560,
271	.hsync_start = 2560 + 128,
272	.hsync_end = 2560 + 128 + 64,
273	.htotal = 2560 + 128 + 64 + 64,
274	.vdisplay = 1600,
275	.vsync_start = 1600 + 4,
276	.vsync_end = 1600 + 4 + 8,
277	.vtotal = 1600 + 4 + 8 + 32,
278	.vrefresh = 60,
279};
280
281static int sharp_panel_get_modes(struct drm_panel *panel)
282{
283	struct drm_display_mode *mode;
284
285	mode = drm_mode_duplicate(panel->drm, &default_mode);
286	if (!mode) {
287		dev_err(panel->drm->dev, "failed to add mode %ux%ux@%u\n",
288			default_mode.hdisplay, default_mode.vdisplay,
289			default_mode.vrefresh);
290		return -ENOMEM;
291	}
292
293	drm_mode_set_name(mode);
294
295	drm_mode_probed_add(panel->connector, mode);
296
297	panel->connector->display_info.width_mm = 217;
298	panel->connector->display_info.height_mm = 136;
299
300	return 1;
301}
302
303static const struct drm_panel_funcs sharp_panel_funcs = {
304	.disable = sharp_panel_disable,
305	.unprepare = sharp_panel_unprepare,
306	.prepare = sharp_panel_prepare,
307	.enable = sharp_panel_enable,
308	.get_modes = sharp_panel_get_modes,
309};
310
311static const struct of_device_id sharp_of_match[] = {
312	{ .compatible = "sharp,lq101r1sx01", },
313	{ }
314};
315MODULE_DEVICE_TABLE(of, sharp_of_match);
316
317static int sharp_panel_add(struct sharp_panel *sharp)
318{
319	struct device *dev = &sharp->link1->dev;
320
321	sharp->mode = &default_mode;
322
323	sharp->supply = devm_regulator_get(&sharp->link1->dev, "power");
324	if (IS_ERR(sharp->supply))
325		return PTR_ERR(sharp->supply);
326
327	sharp->backlight = devm_of_find_backlight(dev);
328
329	if (IS_ERR(sharp->backlight))
330		return PTR_ERR(sharp->backlight);
331
332	drm_panel_init(&sharp->base);
333	sharp->base.funcs = &sharp_panel_funcs;
334	sharp->base.dev = &sharp->link1->dev;
335
336	return drm_panel_add(&sharp->base);
337}
338
339static void sharp_panel_del(struct sharp_panel *sharp)
340{
341	if (sharp->base.dev)
342		drm_panel_remove(&sharp->base);
343
344	if (sharp->link2)
345		put_device(&sharp->link2->dev);
346}
347
348static int sharp_panel_probe(struct mipi_dsi_device *dsi)
349{
350	struct mipi_dsi_device *secondary = NULL;
351	struct sharp_panel *sharp;
352	struct device_node *np;
353	int err;
354
355	dsi->lanes = 4;
356	dsi->format = MIPI_DSI_FMT_RGB888;
357	dsi->mode_flags = MIPI_DSI_MODE_LPM;
358
359	/* Find DSI-LINK1 */
360	np = of_parse_phandle(dsi->dev.of_node, "link2", 0);
361	if (np) {
362		secondary = of_find_mipi_dsi_device_by_node(np);
363		of_node_put(np);
364
365		if (!secondary)
366			return -EPROBE_DEFER;
367	}
368
369	/* register a panel for only the DSI-LINK1 interface */
370	if (secondary) {
371		sharp = devm_kzalloc(&dsi->dev, sizeof(*sharp), GFP_KERNEL);
372		if (!sharp) {
373			put_device(&secondary->dev);
374			return -ENOMEM;
375		}
376
377		mipi_dsi_set_drvdata(dsi, sharp);
378
379		sharp->link2 = secondary;
380		sharp->link1 = dsi;
381
382		err = sharp_panel_add(sharp);
383		if (err < 0) {
384			put_device(&secondary->dev);
385			return err;
386		}
387	}
388
389	err = mipi_dsi_attach(dsi);
390	if (err < 0) {
391		if (secondary)
392			sharp_panel_del(sharp);
393
394		return err;
395	}
396
397	return 0;
398}
399
400static int sharp_panel_remove(struct mipi_dsi_device *dsi)
401{
402	struct sharp_panel *sharp = mipi_dsi_get_drvdata(dsi);
403	int err;
404
405	/* only detach from host for the DSI-LINK2 interface */
406	if (!sharp) {
407		mipi_dsi_detach(dsi);
408		return 0;
409	}
410
411	err = sharp_panel_disable(&sharp->base);
412	if (err < 0)
413		dev_err(&dsi->dev, "failed to disable panel: %d\n", err);
414
415	err = mipi_dsi_detach(dsi);
416	if (err < 0)
417		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", err);
418
419	sharp_panel_del(sharp);
420
421	return 0;
422}
423
424static void sharp_panel_shutdown(struct mipi_dsi_device *dsi)
425{
426	struct sharp_panel *sharp = mipi_dsi_get_drvdata(dsi);
427
428	/* nothing to do for DSI-LINK2 */
429	if (!sharp)
430		return;
431
432	sharp_panel_disable(&sharp->base);
433}
434
435static struct mipi_dsi_driver sharp_panel_driver = {
436	.driver = {
437		.name = "panel-sharp-lq101r1sx01",
438		.of_match_table = sharp_of_match,
439	},
440	.probe = sharp_panel_probe,
441	.remove = sharp_panel_remove,
442	.shutdown = sharp_panel_shutdown,
443};
444module_mipi_dsi_driver(sharp_panel_driver);
445
446MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
447MODULE_DESCRIPTION("Sharp LQ101R1SX01 panel driver");
448MODULE_LICENSE("GPL v2");