1/*
  2 * ld9040 AMOLED LCD drm_panel driver.
  3 *
  4 * Copyright (c) 2014 Samsung Electronics Co., Ltd
  5 * Derived from drivers/video/backlight/ld9040.c
  6 *
  7 * Andrzej Hajda <a.hajda@samsung.com>
  8 *
  9 * This program is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License version 2 as
 11 * published by the Free Software Foundation.
 12*/
 13
 14#include <drm/drmP.h>
 15#include <drm/drm_panel.h>
 16
 17#include <linux/gpio/consumer.h>
 18#include <linux/regulator/consumer.h>
 19#include <linux/spi/spi.h>
 20
 21#include <video/mipi_display.h>
 22#include <video/of_videomode.h>
 23#include <video/videomode.h>
 24
 25/* Manufacturer Command Set */
 26#define MCS_MANPWR		0xb0
 27#define MCS_ELVSS_ON		0xb1
 28#define MCS_USER_SETTING	0xf0
 29#define MCS_DISPCTL		0xf2
 30#define MCS_GTCON		0xf7
 31#define MCS_PANEL_CONDITION	0xf8
 32#define MCS_GAMMA_SET1		0xf9
 33#define MCS_GAMMA_CTRL		0xfb
 34
 35/* array of gamma tables for gamma value 2.2 */
 36static u8 const ld9040_gammas[25][22] = {
 37	{ 0xf9, 0x00, 0x13, 0xb2, 0xba, 0xd2, 0x00, 0x30, 0x00, 0xaf, 0xc0,
 38	  0xb8, 0xcd, 0x00, 0x3d, 0x00, 0xa8, 0xb8, 0xb7, 0xcd, 0x00, 0x44 },
 39	{ 0xf9, 0x00, 0x13, 0xb9, 0xb9, 0xd0, 0x00, 0x3c, 0x00, 0xaf, 0xbf,
 40	  0xb6, 0xcb, 0x00, 0x4b, 0x00, 0xa8, 0xb9, 0xb5, 0xcc, 0x00, 0x52 },
 41	{ 0xf9, 0x00, 0x13, 0xba, 0xb9, 0xcd, 0x00, 0x41, 0x00, 0xb0, 0xbe,
 42	  0xb5, 0xc9, 0x00, 0x51, 0x00, 0xa9, 0xb9, 0xb5, 0xca, 0x00, 0x57 },
 43	{ 0xf9, 0x00, 0x13, 0xb9, 0xb8, 0xcd, 0x00, 0x46, 0x00, 0xb1, 0xbc,
 44	  0xb5, 0xc8, 0x00, 0x56, 0x00, 0xaa, 0xb8, 0xb4, 0xc9, 0x00, 0x5d },
 45	{ 0xf9, 0x00, 0x13, 0xba, 0xb8, 0xcb, 0x00, 0x4b, 0x00, 0xb3, 0xbc,
 46	  0xb4, 0xc7, 0x00, 0x5c, 0x00, 0xac, 0xb8, 0xb4, 0xc8, 0x00, 0x62 },
 47	{ 0xf9, 0x00, 0x13, 0xbb, 0xb7, 0xca, 0x00, 0x4f, 0x00, 0xb4, 0xbb,
 48	  0xb3, 0xc7, 0x00, 0x60, 0x00, 0xad, 0xb8, 0xb4, 0xc7, 0x00, 0x67 },
 49	{ 0xf9, 0x00, 0x47, 0xba, 0xb6, 0xca, 0x00, 0x53, 0x00, 0xb5, 0xbb,
 50	  0xb3, 0xc6, 0x00, 0x65, 0x00, 0xae, 0xb8, 0xb3, 0xc7, 0x00, 0x6c },
 51	{ 0xf9, 0x00, 0x71, 0xbb, 0xb5, 0xc8, 0x00, 0x57, 0x00, 0xb5, 0xbb,
 52	  0xb0, 0xc5, 0x00, 0x6a, 0x00, 0xae, 0xb9, 0xb1, 0xc6, 0x00, 0x70 },
 53	{ 0xf9, 0x00, 0x7b, 0xbb, 0xb4, 0xc8, 0x00, 0x5b, 0x00, 0xb5, 0xba,
 54	  0xb1, 0xc4, 0x00, 0x6e, 0x00, 0xae, 0xb9, 0xb0, 0xc5, 0x00, 0x75 },
 55	{ 0xf9, 0x00, 0x82, 0xba, 0xb4, 0xc7, 0x00, 0x5f, 0x00, 0xb5, 0xba,
 56	  0xb0, 0xc3, 0x00, 0x72, 0x00, 0xae, 0xb8, 0xb0, 0xc3, 0x00, 0x7a },
 57	{ 0xf9, 0x00, 0x89, 0xba, 0xb3, 0xc8, 0x00, 0x62, 0x00, 0xb6, 0xba,
 58	  0xaf, 0xc3, 0x00, 0x76, 0x00, 0xaf, 0xb7, 0xae, 0xc4, 0x00, 0x7e },
 59	{ 0xf9, 0x00, 0x8b, 0xb9, 0xb3, 0xc7, 0x00, 0x65, 0x00, 0xb7, 0xb8,
 60	  0xaf, 0xc3, 0x00, 0x7a, 0x00, 0x80, 0xb6, 0xae, 0xc4, 0x00, 0x81 },
 61	{ 0xf9, 0x00, 0x93, 0xba, 0xb3, 0xc5, 0x00, 0x69, 0x00, 0xb8, 0xb9,
 62	  0xae, 0xc1, 0x00, 0x7f, 0x00, 0xb0, 0xb6, 0xae, 0xc3, 0x00, 0x85 },
 63	{ 0xf9, 0x00, 0x97, 0xba, 0xb2, 0xc5, 0x00, 0x6c, 0x00, 0xb8, 0xb8,
 64	  0xae, 0xc1, 0x00, 0x82, 0x00, 0xb0, 0xb6, 0xae, 0xc2, 0x00, 0x89 },
 65	{ 0xf9, 0x00, 0x9a, 0xba, 0xb1, 0xc4, 0x00, 0x6f, 0x00, 0xb8, 0xb8,
 66	  0xad, 0xc0, 0x00, 0x86, 0x00, 0xb0, 0xb7, 0xad, 0xc0, 0x00, 0x8d },
 67	{ 0xf9, 0x00, 0x9c, 0xb9, 0xb0, 0xc4, 0x00, 0x72, 0x00, 0xb8, 0xb8,
 68	  0xac, 0xbf, 0x00, 0x8a, 0x00, 0xb0, 0xb6, 0xac, 0xc0, 0x00, 0x91 },
 69	{ 0xf9, 0x00, 0x9e, 0xba, 0xb0, 0xc2, 0x00, 0x75, 0x00, 0xb9, 0xb8,
 70	  0xab, 0xbe, 0x00, 0x8e, 0x00, 0xb0, 0xb6, 0xac, 0xbf, 0x00, 0x94 },
 71	{ 0xf9, 0x00, 0xa0, 0xb9, 0xaf, 0xc3, 0x00, 0x77, 0x00, 0xb9, 0xb7,
 72	  0xab, 0xbe, 0x00, 0x90, 0x00, 0xb0, 0xb6, 0xab, 0xbf, 0x00, 0x97 },
 73	{ 0xf9, 0x00, 0xa2, 0xb9, 0xaf, 0xc2, 0x00, 0x7a, 0x00, 0xb9, 0xb7,
 74	  0xaa, 0xbd, 0x00, 0x94, 0x00, 0xb0, 0xb5, 0xab, 0xbf, 0x00, 0x9a },
 75	{ 0xf9, 0x00, 0xa4, 0xb9, 0xaf, 0xc1, 0x00, 0x7d, 0x00, 0xb9, 0xb6,
 76	  0xaa, 0xbb, 0x00, 0x97, 0x00, 0xb1, 0xb5, 0xaa, 0xbf, 0x00, 0x9d },
 77	{ 0xf9, 0x00, 0xa4, 0xb8, 0xb0, 0xbf, 0x00, 0x80, 0x00, 0xb8, 0xb6,
 78	  0xaa, 0xbc, 0x00, 0x9a, 0x00, 0xb0, 0xb5, 0xab, 0xbd, 0x00, 0xa0 },
 79	{ 0xf9, 0x00, 0xa8, 0xb8, 0xae, 0xbe, 0x00, 0x84, 0x00, 0xb9, 0xb7,
 80	  0xa8, 0xbc, 0x00, 0x9d, 0x00, 0xb2, 0xb5, 0xaa, 0xbc, 0x00, 0xa4 },
 81	{ 0xf9, 0x00, 0xa9, 0xb6, 0xad, 0xbf, 0x00, 0x86, 0x00, 0xb8, 0xb5,
 82	  0xa8, 0xbc, 0x00, 0xa0, 0x00, 0xb3, 0xb3, 0xa9, 0xbc, 0x00, 0xa7 },
 83	{ 0xf9, 0x00, 0xa9, 0xb7, 0xae, 0xbd, 0x00, 0x89, 0x00, 0xb7, 0xb6,
 84	  0xa8, 0xba, 0x00, 0xa4, 0x00, 0xb1, 0xb4, 0xaa, 0xbb, 0x00, 0xaa },
 85	{ 0xf9, 0x00, 0xa7, 0xb4, 0xae, 0xbf, 0x00, 0x91, 0x00, 0xb2, 0xb4,
 86	  0xaa, 0xbb, 0x00, 0xac, 0x00, 0xb3, 0xb1, 0xaa, 0xbc, 0x00, 0xb3 },
 87};
 88
 89struct ld9040 {
 90	struct device *dev;
 91	struct drm_panel panel;
 92
 93	struct regulator_bulk_data supplies[2];
 94	struct gpio_desc *reset_gpio;
 95	u32 power_on_delay;
 96	u32 reset_delay;
 97	struct videomode vm;
 98	u32 width_mm;
 99	u32 height_mm;
100
101	int brightness;
102
103	/* This field is tested by functions directly accessing bus before
104	 * transfer, transfer is skipped if it is set. In case of transfer
105	 * failure or unexpected response the field is set to error value.
106	 * Such construct allows to eliminate many checks in higher level
107	 * functions.
108	 */
109	int error;
110};
111
112#define panel_to_ld9040(p) container_of(p, struct ld9040, panel)
113
114static int ld9040_clear_error(struct ld9040 *ctx)
115{
116	int ret = ctx->error;
117
118	ctx->error = 0;
119	return ret;
120}
121
122static int ld9040_spi_write_word(struct ld9040 *ctx, u16 data)
123{
124	struct spi_device *spi = to_spi_device(ctx->dev);
125	struct spi_transfer xfer = {
126		.len		= 2,
127		.tx_buf		= &data,
128	};
129	struct spi_message msg;
130
131	spi_message_init(&msg);
132	spi_message_add_tail(&xfer, &msg);
133
134	return spi_sync(spi, &msg);
135}
136
137static void ld9040_dcs_write(struct ld9040 *ctx, const u8 *data, size_t len)
138{
139	int ret = 0;
140
141	if (ctx->error < 0 || len == 0)
142		return;
143
144	dev_dbg(ctx->dev, "writing dcs seq: %*ph\n", len, data);
145	ret = ld9040_spi_write_word(ctx, *data);
146
147	while (!ret && --len) {
148		++data;
149		ret = ld9040_spi_write_word(ctx, *data | 0x100);
150	}
151
152	if (ret) {
153		dev_err(ctx->dev, "error %d writing dcs seq: %*ph\n", ret, len,
154			data);
155		ctx->error = ret;
156	}
157
158	usleep_range(300, 310);
159}
160
161#define ld9040_dcs_write_seq_static(ctx, seq...) \
162({\
163	static const u8 d[] = { seq };\
164	ld9040_dcs_write(ctx, d, ARRAY_SIZE(d));\
165})
166
167static void ld9040_brightness_set(struct ld9040 *ctx)
168{
169	ld9040_dcs_write(ctx, ld9040_gammas[ctx->brightness],
170			 ARRAY_SIZE(ld9040_gammas[ctx->brightness]));
171
172	ld9040_dcs_write_seq_static(ctx, MCS_GAMMA_CTRL, 0x02, 0x5a);
173}
174
175static void ld9040_init(struct ld9040 *ctx)
176{
177	ld9040_dcs_write_seq_static(ctx, MCS_USER_SETTING, 0x5a, 0x5a);
178	ld9040_dcs_write_seq_static(ctx, MCS_PANEL_CONDITION,
179		0x05, 0x65, 0x96, 0x71, 0x7d, 0x19, 0x3b, 0x0d,
180		0x19, 0x7e, 0x0d, 0xe2, 0x00, 0x00, 0x7e, 0x7d,
181		0x07, 0x07, 0x20, 0x20, 0x20, 0x02, 0x02);
182	ld9040_dcs_write_seq_static(ctx, MCS_DISPCTL,
183		0x02, 0x08, 0x08, 0x10, 0x10);
184	ld9040_dcs_write_seq_static(ctx, MCS_MANPWR, 0x04);
185	ld9040_dcs_write_seq_static(ctx, MCS_ELVSS_ON, 0x0d, 0x00, 0x16);
186	ld9040_dcs_write_seq_static(ctx, MCS_GTCON, 0x09, 0x00, 0x00);
187	ld9040_brightness_set(ctx);
188	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_EXIT_SLEEP_MODE);
189	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_ON);
190}
191
192static int ld9040_power_on(struct ld9040 *ctx)
193{
194	int ret;
195
196	ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
197	if (ret < 0)
198		return ret;
199
200	msleep(ctx->power_on_delay);
201	gpiod_set_value(ctx->reset_gpio, 0);
202	msleep(ctx->reset_delay);
203	gpiod_set_value(ctx->reset_gpio, 1);
204	msleep(ctx->reset_delay);
205
206	return 0;
207}
208
209static int ld9040_power_off(struct ld9040 *ctx)
210{
211	return regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
212}
213
214static int ld9040_disable(struct drm_panel *panel)
215{
216	struct ld9040 *ctx = panel_to_ld9040(panel);
217
218	msleep(120);
219	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_OFF);
220	ld9040_dcs_write_seq_static(ctx, MIPI_DCS_ENTER_SLEEP_MODE);
221	msleep(40);
222
223	ld9040_clear_error(ctx);
224
225	return ld9040_power_off(ctx);
226}
227
228static int ld9040_enable(struct drm_panel *panel)
229{
230	struct ld9040 *ctx = panel_to_ld9040(panel);
231	int ret;
232
233	ret = ld9040_power_on(ctx);
234	if (ret < 0)
235		return ret;
236
237	ld9040_init(ctx);
238
239	ret = ld9040_clear_error(ctx);
240
241	if (ret < 0)
242		ld9040_disable(panel);
243
244	return ret;
245}
246
247static int ld9040_get_modes(struct drm_panel *panel)
248{
249	struct drm_connector *connector = panel->connector;
250	struct ld9040 *ctx = panel_to_ld9040(panel);
251	struct drm_display_mode *mode;
252
253	mode = drm_mode_create(connector->dev);
254	if (!mode) {
255		DRM_ERROR("failed to create a new display mode\n");
256		return 0;
257	}
258
259	drm_display_mode_from_videomode(&ctx->vm, mode);
260	mode->width_mm = ctx->width_mm;
261	mode->height_mm = ctx->height_mm;
262	connector->display_info.width_mm = mode->width_mm;
263	connector->display_info.height_mm = mode->height_mm;
264
265	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
266	drm_mode_probed_add(connector, mode);
267
268	return 1;
269}
270
271static const struct drm_panel_funcs ld9040_drm_funcs = {
272	.disable = ld9040_disable,
273	.enable = ld9040_enable,
274	.get_modes = ld9040_get_modes,
275};
276
277static int ld9040_parse_dt(struct ld9040 *ctx)
278{
279	struct device *dev = ctx->dev;
280	struct device_node *np = dev->of_node;
281	int ret;
282
283	ret = of_get_videomode(np, &ctx->vm, 0);
284	if (ret < 0)
285		return ret;
286
287	of_property_read_u32(np, "power-on-delay", &ctx->power_on_delay);
288	of_property_read_u32(np, "reset-delay", &ctx->reset_delay);
289	of_property_read_u32(np, "panel-width-mm", &ctx->width_mm);
290	of_property_read_u32(np, "panel-height-mm", &ctx->height_mm);
291
292	return 0;
293}
294
295static int ld9040_probe(struct spi_device *spi)
296{
297	struct device *dev = &spi->dev;
298	struct ld9040 *ctx;
299	int ret;
300
301	ctx = devm_kzalloc(dev, sizeof(struct ld9040), GFP_KERNEL);
302	if (!ctx)
303		return -ENOMEM;
304
305	spi_set_drvdata(spi, ctx);
306
307	ctx->dev = dev;
308	ctx->brightness = ARRAY_SIZE(ld9040_gammas) - 1;
309
310	ret = ld9040_parse_dt(ctx);
311	if (ret < 0)
312		return ret;
313
314	ctx->supplies[0].supply = "vdd3";
315	ctx->supplies[1].supply = "vci";
316	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ctx->supplies),
317				      ctx->supplies);
318	if (ret < 0)
319		return ret;
320
321	ctx->reset_gpio = devm_gpiod_get(dev, "reset");
322	if (IS_ERR(ctx->reset_gpio)) {
323		dev_err(dev, "cannot get reset-gpios %ld\n",
324			PTR_ERR(ctx->reset_gpio));
325		return PTR_ERR(ctx->reset_gpio);
326	}
327	ret = gpiod_direction_output(ctx->reset_gpio, 1);
328	if (ret < 0) {
329		dev_err(dev, "cannot configure reset-gpios %d\n", ret);
330		return ret;
331	}
332
333	spi->bits_per_word = 9;
334	ret = spi_setup(spi);
335	if (ret < 0) {
336		dev_err(dev, "spi setup failed.\n");
337		return ret;
338	}
339
340	drm_panel_init(&ctx->panel);
341	ctx->panel.dev = dev;
342	ctx->panel.funcs = &ld9040_drm_funcs;
343
344	return drm_panel_add(&ctx->panel);
345}
346
347static int ld9040_remove(struct spi_device *spi)
348{
349	struct ld9040 *ctx = spi_get_drvdata(spi);
350
351	ld9040_power_off(ctx);
352	drm_panel_remove(&ctx->panel);
353
354	return 0;
355}
356
357static struct of_device_id ld9040_of_match[] = {
358	{ .compatible = "samsung,ld9040" },
359	{ }
360};
361MODULE_DEVICE_TABLE(of, ld9040_of_match);
362
363static struct spi_driver ld9040_driver = {
364	.probe		= ld9040_probe,
365	.remove		= ld9040_remove,
366	.driver = {
367		.name	= "ld9040",
368		.owner	= THIS_MODULE,
369		.of_match_table = ld9040_of_match,
370	},
371};
372module_spi_driver(ld9040_driver);
373
374MODULE_AUTHOR("Andrzej Hajda <a.hajda@samsung.com>");
375MODULE_DESCRIPTION("ld9040 LCD Driver");
376MODULE_LICENSE("GPL v2");