1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Innolux/Chimei EJ030NA TFT LCD panel driver
  4 *
  5 * Copyright (C) 2020, Paul Cercueil <paul@crapouillou.net>
  6 * Copyright (C) 2020, Christophe Branchereau <cbranchereau@gmail.com>
  7 */
  8
  9#include <linux/delay.h>
 10#include <linux/device.h>
 11#include <linux/gpio/consumer.h>
 12#include <linux/media-bus-format.h>
 13#include <linux/module.h>
 14#include <linux/of_device.h>
 15#include <linux/regmap.h>
 16#include <linux/regulator/consumer.h>
 17#include <linux/spi/spi.h>
 18
 19#include <drm/drm_modes.h>
 20#include <drm/drm_panel.h>
 21
 22struct ej030na_info {
 23	const struct drm_display_mode *display_modes;
 24	unsigned int num_modes;
 25	u16 width_mm, height_mm;
 26	u32 bus_format, bus_flags;
 27};
 28
 29struct ej030na {
 30	struct drm_panel panel;
 31	struct spi_device *spi;
 32	struct regmap *map;
 33
 34	const struct ej030na_info *panel_info;
 35
 36	struct regulator *supply;
 37	struct gpio_desc *reset_gpio;
 38};
 39
 40static inline struct ej030na *to_ej030na(struct drm_panel *panel)
 41{
 42	return container_of(panel, struct ej030na, panel);
 43}
 44
 45static const struct reg_sequence ej030na_init_sequence[] = {
 46	{ 0x05, 0x1e },
 47	{ 0x05, 0x5c },
 48	{ 0x02, 0x14 },
 49	{ 0x03, 0x40 },
 50	{ 0x04, 0x07 },
 51	{ 0x06, 0x12 },
 52	{ 0x07, 0xd2 },
 53	{ 0x0c, 0x06 },
 54	{ 0x0d, 0x40 },
 55	{ 0x0e, 0x40 },
 56	{ 0x0f, 0x40 },
 57	{ 0x10, 0x40 },
 58	{ 0x11, 0x40 },
 59	{ 0x2f, 0x40 },
 60	{ 0x5a, 0x02 },
 61
 62	{ 0x30, 0x07 },
 63	{ 0x31, 0x57 },
 64	{ 0x32, 0x53 },
 65	{ 0x33, 0x77 },
 66	{ 0x34, 0xb8 },
 67	{ 0x35, 0xbd },
 68	{ 0x36, 0xb8 },
 69	{ 0x37, 0xe7 },
 70	{ 0x38, 0x04 },
 71	{ 0x39, 0xff },
 72
 73	{ 0x40, 0x0b },
 74	{ 0x41, 0xb8 },
 75	{ 0x42, 0xab },
 76	{ 0x43, 0xb9 },
 77	{ 0x44, 0x6a },
 78	{ 0x45, 0x56 },
 79	{ 0x46, 0x61 },
 80	{ 0x47, 0x08 },
 81	{ 0x48, 0x0f },
 82	{ 0x49, 0x0f },
 83};
 84
 85static int ej030na_prepare(struct drm_panel *panel)
 86{
 87	struct ej030na *priv = to_ej030na(panel);
 88	struct device *dev = &priv->spi->dev;
 89	int err;
 90
 91	err = regulator_enable(priv->supply);
 92	if (err) {
 93		dev_err(dev, "Failed to enable power supply: %d\n", err);
 94		return err;
 95	}
 96
 97	/* Reset the chip */
 98	gpiod_set_value_cansleep(priv->reset_gpio, 1);
 99	usleep_range(50, 150);
100	gpiod_set_value_cansleep(priv->reset_gpio, 0);
101	usleep_range(50, 150);
102
103	err = regmap_multi_reg_write(priv->map, ej030na_init_sequence,
104				     ARRAY_SIZE(ej030na_init_sequence));
105	if (err) {
106		dev_err(dev, "Failed to init registers: %d\n", err);
107		goto err_disable_regulator;
108	}
109
110	return 0;
111
112err_disable_regulator:
113	regulator_disable(priv->supply);
114	return err;
115}
116
117static int ej030na_unprepare(struct drm_panel *panel)
118{
119	struct ej030na *priv = to_ej030na(panel);
120
121	gpiod_set_value_cansleep(priv->reset_gpio, 1);
122	regulator_disable(priv->supply);
123
124	return 0;
125}
126
127static int ej030na_enable(struct drm_panel *panel)
128{
129	struct ej030na *priv = to_ej030na(panel);
130
131	/* standby off */
132	regmap_write(priv->map, 0x2b, 0x01);
133
134	if (panel->backlight) {
135		/* Wait for the picture to be ready before enabling backlight */
136		msleep(120);
137	}
138
139	return 0;
140}
141
142static int ej030na_disable(struct drm_panel *panel)
143{
144	struct ej030na *priv = to_ej030na(panel);
145
146	/* standby on */
147	regmap_write(priv->map, 0x2b, 0x00);
148
149	return 0;
150}
151
152static int ej030na_get_modes(struct drm_panel *panel,
153			     struct drm_connector *connector)
154{
155	struct ej030na *priv = to_ej030na(panel);
156	const struct ej030na_info *panel_info = priv->panel_info;
157	struct drm_display_mode *mode;
158	unsigned int i;
159
160	for (i = 0; i < panel_info->num_modes; i++) {
161		mode = drm_mode_duplicate(connector->dev,
162					  &panel_info->display_modes[i]);
163		if (!mode)
164			return -ENOMEM;
165
166		drm_mode_set_name(mode);
167
168		mode->type = DRM_MODE_TYPE_DRIVER;
169		if (panel_info->num_modes == 1)
170			mode->type |= DRM_MODE_TYPE_PREFERRED;
171
172		drm_mode_probed_add(connector, mode);
173	}
174
175	connector->display_info.bpc = 8;
176	connector->display_info.width_mm = panel_info->width_mm;
177	connector->display_info.height_mm = panel_info->height_mm;
178
179	drm_display_info_set_bus_formats(&connector->display_info,
180					 &panel_info->bus_format, 1);
181	connector->display_info.bus_flags = panel_info->bus_flags;
182
183	return panel_info->num_modes;
184}
185
186static const struct drm_panel_funcs ej030na_funcs = {
187	.prepare	= ej030na_prepare,
188	.unprepare	= ej030na_unprepare,
189	.enable		= ej030na_enable,
190	.disable	= ej030na_disable,
191	.get_modes	= ej030na_get_modes,
192};
193
194static const struct regmap_config ej030na_regmap_config = {
195	.reg_bits = 8,
196	.val_bits = 8,
197	.max_register = 0x5a,
198};
199
200static int ej030na_probe(struct spi_device *spi)
201{
202	struct device *dev = &spi->dev;
203	struct ej030na *priv;
204	int err;
205
206	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
207	if (!priv)
208		return -ENOMEM;
209
210	priv->spi = spi;
211	spi_set_drvdata(spi, priv);
212
213	priv->map = devm_regmap_init_spi(spi, &ej030na_regmap_config);
214	if (IS_ERR(priv->map)) {
215		dev_err(dev, "Unable to init regmap\n");
216		return PTR_ERR(priv->map);
217	}
218
219	priv->panel_info = of_device_get_match_data(dev);
220	if (!priv->panel_info)
221		return -EINVAL;
222
223	priv->supply = devm_regulator_get(dev, "power");
224	if (IS_ERR(priv->supply))
225		return dev_err_probe(dev, PTR_ERR(priv->supply),
226				     "Failed to get power supply\n");
227
228	priv->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
229	if (IS_ERR(priv->reset_gpio))
230		return dev_err_probe(dev, PTR_ERR(priv->reset_gpio),
231				     "Failed to get reset GPIO\n");
232
233	drm_panel_init(&priv->panel, dev, &ej030na_funcs,
234		       DRM_MODE_CONNECTOR_DPI);
235
236	err = drm_panel_of_backlight(&priv->panel);
237	if (err)
238		return err;
239
240	drm_panel_add(&priv->panel);
241
242	return 0;
243}
244
245static void ej030na_remove(struct spi_device *spi)
246{
247	struct ej030na *priv = spi_get_drvdata(spi);
248
249	drm_panel_remove(&priv->panel);
250	drm_panel_disable(&priv->panel);
251	drm_panel_unprepare(&priv->panel);
252}
253
254static const struct drm_display_mode ej030na_modes[] = {
255	{ /* 60 Hz */
256		.clock = 14400,
257		.hdisplay = 320,
258		.hsync_start = 320 + 10,
259		.hsync_end = 320 + 10 + 37,
260		.htotal = 320 + 10 + 37 + 33,
261		.vdisplay = 480,
262		.vsync_start = 480 + 102,
263		.vsync_end = 480 + 102 + 9 + 9,
264		.vtotal = 480 + 102 + 9 + 9,
265		.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
266	},
267	{ /* 50 Hz */
268		.clock = 12000,
269		.hdisplay = 320,
270		.hsync_start = 320 + 10,
271		.hsync_end = 320 + 10 + 37,
272		.htotal = 320 + 10 + 37 + 33,
273		.vdisplay = 480,
274		.vsync_start = 480 + 102,
275		.vsync_end = 480 + 102 + 9,
276		.vtotal = 480 + 102 + 9 + 9,
277		.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
278	},
279};
280
281static const struct ej030na_info ej030na_info = {
282	.display_modes = ej030na_modes,
283	.num_modes = ARRAY_SIZE(ej030na_modes),
284	.width_mm = 70,
285	.height_mm = 51,
286	.bus_format = MEDIA_BUS_FMT_RGB888_3X8_DELTA,
287	.bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE | DRM_BUS_FLAG_DE_LOW,
288};
289
290static const struct of_device_id ej030na_of_match[] = {
291	{ .compatible = "innolux,ej030na", .data = &ej030na_info },
292	{ /* sentinel */ }
293};
294MODULE_DEVICE_TABLE(of, ej030na_of_match);
295
296static struct spi_driver ej030na_driver = {
297	.driver = {
298		.name = "panel-innolux-ej030na",
299		.of_match_table = ej030na_of_match,
300	},
301	.probe = ej030na_probe,
302	.remove = ej030na_remove,
303};
304module_spi_driver(ej030na_driver);
305
306MODULE_AUTHOR("Paul Cercueil <paul@crapouillou.net>");
307MODULE_AUTHOR("Christophe Branchereau <cbranchereau@gmail.com>");
308MODULE_LICENSE("GPL v2");