1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Toppoly TD028TTEC1 Panel Driver
4 *
5 * Copyright (C) 2019 Texas Instruments Incorporated
6 *
7 * Based on the omapdrm-specific panel-tpo-td028ttec1 driver
8 *
9 * Copyright (C) 2008 Nokia Corporation
10 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
11 *
12 * Neo 1973 code (jbt6k74.c):
13 * Copyright (C) 2006-2007 OpenMoko, Inc.
14 * Author: Harald Welte <laforge@openmoko.org>
15 *
16 * Ported and adapted from Neo 1973 U-Boot by:
17 * H. Nikolaus Schaller <hns@goldelico.com>
18 */
19
20#include <linux/delay.h>
21#include <linux/module.h>
22#include <linux/spi/spi.h>
23
24#include <drm/drm_connector.h>
25#include <drm/drm_modes.h>
26#include <drm/drm_panel.h>
27
28#define JBT_COMMAND			0x000
29#define JBT_DATA			0x100
30
31#define JBT_REG_SLEEP_IN		0x10
32#define JBT_REG_SLEEP_OUT		0x11
33
34#define JBT_REG_DISPLAY_OFF		0x28
35#define JBT_REG_DISPLAY_ON		0x29
36
37#define JBT_REG_RGB_FORMAT		0x3a
38#define JBT_REG_QUAD_RATE		0x3b
39
40#define JBT_REG_POWER_ON_OFF		0xb0
41#define JBT_REG_BOOSTER_OP		0xb1
42#define JBT_REG_BOOSTER_MODE		0xb2
43#define JBT_REG_BOOSTER_FREQ		0xb3
44#define JBT_REG_OPAMP_SYSCLK		0xb4
45#define JBT_REG_VSC_VOLTAGE		0xb5
46#define JBT_REG_VCOM_VOLTAGE		0xb6
47#define JBT_REG_EXT_DISPL		0xb7
48#define JBT_REG_OUTPUT_CONTROL		0xb8
49#define JBT_REG_DCCLK_DCEV		0xb9
50#define JBT_REG_DISPLAY_MODE1		0xba
51#define JBT_REG_DISPLAY_MODE2		0xbb
52#define JBT_REG_DISPLAY_MODE		0xbc
53#define JBT_REG_ASW_SLEW		0xbd
54#define JBT_REG_DUMMY_DISPLAY		0xbe
55#define JBT_REG_DRIVE_SYSTEM		0xbf
56
57#define JBT_REG_SLEEP_OUT_FR_A		0xc0
58#define JBT_REG_SLEEP_OUT_FR_B		0xc1
59#define JBT_REG_SLEEP_OUT_FR_C		0xc2
60#define JBT_REG_SLEEP_IN_LCCNT_D	0xc3
61#define JBT_REG_SLEEP_IN_LCCNT_E	0xc4
62#define JBT_REG_SLEEP_IN_LCCNT_F	0xc5
63#define JBT_REG_SLEEP_IN_LCCNT_G	0xc6
64
65#define JBT_REG_GAMMA1_FINE_1		0xc7
66#define JBT_REG_GAMMA1_FINE_2		0xc8
67#define JBT_REG_GAMMA1_INCLINATION	0xc9
68#define JBT_REG_GAMMA1_BLUE_OFFSET	0xca
69
70#define JBT_REG_BLANK_CONTROL		0xcf
71#define JBT_REG_BLANK_TH_TV		0xd0
72#define JBT_REG_CKV_ON_OFF		0xd1
73#define JBT_REG_CKV_1_2			0xd2
74#define JBT_REG_OEV_TIMING		0xd3
75#define JBT_REG_ASW_TIMING_1		0xd4
76#define JBT_REG_ASW_TIMING_2		0xd5
77
78#define JBT_REG_HCLOCK_VGA		0xec
79#define JBT_REG_HCLOCK_QVGA		0xed
80
81struct td028ttec1_panel {
82	struct drm_panel panel;
83
84	struct spi_device *spi;
85};
86
87#define to_td028ttec1_device(p) container_of(p, struct td028ttec1_panel, panel)
88
89/*
90 * noinline_for_stack so we don't get multiple copies of tx_buf
91 * on the stack in case of gcc-plugin-structleak
92 */
93static int noinline_for_stack
94jbt_ret_write_0(struct td028ttec1_panel *lcd, u8 reg, int *err)
95{
96	struct spi_device *spi = lcd->spi;
97	u16 tx_buf = JBT_COMMAND | reg;
98	int ret;
99
100	if (err && *err)
101		return *err;
102
103	ret = spi_write(spi, (u8 *)&tx_buf, sizeof(tx_buf));
104	if (ret < 0) {
105		dev_err(&spi->dev, "%s: SPI write failed: %d\n", __func__, ret);
106		if (err)
107			*err = ret;
108	}
109
110	return ret;
111}
112
113static int noinline_for_stack
114jbt_reg_write_1(struct td028ttec1_panel *lcd,
115		u8 reg, u8 data, int *err)
116{
117	struct spi_device *spi = lcd->spi;
118	u16 tx_buf[2];
119	int ret;
120
121	if (err && *err)
122		return *err;
123
124	tx_buf[0] = JBT_COMMAND | reg;
125	tx_buf[1] = JBT_DATA | data;
126
127	ret = spi_write(spi, (u8 *)tx_buf, sizeof(tx_buf));
128	if (ret < 0) {
129		dev_err(&spi->dev, "%s: SPI write failed: %d\n", __func__, ret);
130		if (err)
131			*err = ret;
132	}
133
134	return ret;
135}
136
137static int noinline_for_stack
138jbt_reg_write_2(struct td028ttec1_panel *lcd,
139		u8 reg, u16 data, int *err)
140{
141	struct spi_device *spi = lcd->spi;
142	u16 tx_buf[3];
143	int ret;
144
145	if (err && *err)
146		return *err;
147
148	tx_buf[0] = JBT_COMMAND | reg;
149	tx_buf[1] = JBT_DATA | (data >> 8);
150	tx_buf[2] = JBT_DATA | (data & 0xff);
151
152	ret = spi_write(spi, (u8 *)tx_buf, sizeof(tx_buf));
153	if (ret < 0) {
154		dev_err(&spi->dev, "%s: SPI write failed: %d\n", __func__, ret);
155		if (err)
156			*err = ret;
157	}
158
159	return ret;
160}
161
162static int td028ttec1_prepare(struct drm_panel *panel)
163{
164	struct td028ttec1_panel *lcd = to_td028ttec1_device(panel);
165	unsigned int i;
166	int ret = 0;
167
168	/* Three times command zero */
169	for (i = 0; i < 3; ++i) {
170		jbt_ret_write_0(lcd, 0x00, &ret);
171		usleep_range(1000, 2000);
172	}
173
174	/* deep standby out */
175	jbt_reg_write_1(lcd, JBT_REG_POWER_ON_OFF, 0x17, &ret);
176
177	/* RGB I/F on, RAM write off, QVGA through, SIGCON enable */
178	jbt_reg_write_1(lcd, JBT_REG_DISPLAY_MODE, 0x80, &ret);
179
180	/* Quad mode off */
181	jbt_reg_write_1(lcd, JBT_REG_QUAD_RATE, 0x00, &ret);
182
183	/* AVDD on, XVDD on */
184	jbt_reg_write_1(lcd, JBT_REG_POWER_ON_OFF, 0x16, &ret);
185
186	/* Output control */
187	jbt_reg_write_2(lcd, JBT_REG_OUTPUT_CONTROL, 0xfff9, &ret);
188
189	/* Sleep mode off */
190	jbt_ret_write_0(lcd, JBT_REG_SLEEP_OUT, &ret);
191
192	/* at this point we have like 50% grey */
193
194	/* initialize register set */
195	jbt_reg_write_1(lcd, JBT_REG_DISPLAY_MODE1, 0x01, &ret);
196	jbt_reg_write_1(lcd, JBT_REG_DISPLAY_MODE2, 0x00, &ret);
197	jbt_reg_write_1(lcd, JBT_REG_RGB_FORMAT, 0x60, &ret);
198	jbt_reg_write_1(lcd, JBT_REG_DRIVE_SYSTEM, 0x10, &ret);
199	jbt_reg_write_1(lcd, JBT_REG_BOOSTER_OP, 0x56, &ret);
200	jbt_reg_write_1(lcd, JBT_REG_BOOSTER_MODE, 0x33, &ret);
201	jbt_reg_write_1(lcd, JBT_REG_BOOSTER_FREQ, 0x11, &ret);
202	jbt_reg_write_1(lcd, JBT_REG_BOOSTER_FREQ, 0x11, &ret);
203	jbt_reg_write_1(lcd, JBT_REG_OPAMP_SYSCLK, 0x02, &ret);
204	jbt_reg_write_1(lcd, JBT_REG_VSC_VOLTAGE, 0x2b, &ret);
205	jbt_reg_write_1(lcd, JBT_REG_VCOM_VOLTAGE, 0x40, &ret);
206	jbt_reg_write_1(lcd, JBT_REG_EXT_DISPL, 0x03, &ret);
207	jbt_reg_write_1(lcd, JBT_REG_DCCLK_DCEV, 0x04, &ret);
208	/*
209	 * default of 0x02 in JBT_REG_ASW_SLEW responsible for 72Hz requirement
210	 * to avoid red / blue flicker
211	 */
212	jbt_reg_write_1(lcd, JBT_REG_ASW_SLEW, 0x04, &ret);
213	jbt_reg_write_1(lcd, JBT_REG_DUMMY_DISPLAY, 0x00, &ret);
214
215	jbt_reg_write_1(lcd, JBT_REG_SLEEP_OUT_FR_A, 0x11, &ret);
216	jbt_reg_write_1(lcd, JBT_REG_SLEEP_OUT_FR_B, 0x11, &ret);
217	jbt_reg_write_1(lcd, JBT_REG_SLEEP_OUT_FR_C, 0x11, &ret);
218	jbt_reg_write_2(lcd, JBT_REG_SLEEP_IN_LCCNT_D, 0x2040, &ret);
219	jbt_reg_write_2(lcd, JBT_REG_SLEEP_IN_LCCNT_E, 0x60c0, &ret);
220	jbt_reg_write_2(lcd, JBT_REG_SLEEP_IN_LCCNT_F, 0x1020, &ret);
221	jbt_reg_write_2(lcd, JBT_REG_SLEEP_IN_LCCNT_G, 0x60c0, &ret);
222
223	jbt_reg_write_2(lcd, JBT_REG_GAMMA1_FINE_1, 0x5533, &ret);
224	jbt_reg_write_1(lcd, JBT_REG_GAMMA1_FINE_2, 0x00, &ret);
225	jbt_reg_write_1(lcd, JBT_REG_GAMMA1_INCLINATION, 0x00, &ret);
226	jbt_reg_write_1(lcd, JBT_REG_GAMMA1_BLUE_OFFSET, 0x00, &ret);
227
228	jbt_reg_write_2(lcd, JBT_REG_HCLOCK_VGA, 0x1f0, &ret);
229	jbt_reg_write_1(lcd, JBT_REG_BLANK_CONTROL, 0x02, &ret);
230	jbt_reg_write_2(lcd, JBT_REG_BLANK_TH_TV, 0x0804, &ret);
231
232	jbt_reg_write_1(lcd, JBT_REG_CKV_ON_OFF, 0x01, &ret);
233	jbt_reg_write_2(lcd, JBT_REG_CKV_1_2, 0x0000, &ret);
234
235	jbt_reg_write_2(lcd, JBT_REG_OEV_TIMING, 0x0d0e, &ret);
236	jbt_reg_write_2(lcd, JBT_REG_ASW_TIMING_1, 0x11a4, &ret);
237	jbt_reg_write_1(lcd, JBT_REG_ASW_TIMING_2, 0x0e, &ret);
238
239	return ret;
240}
241
242static int td028ttec1_enable(struct drm_panel *panel)
243{
244	struct td028ttec1_panel *lcd = to_td028ttec1_device(panel);
245
246	return jbt_ret_write_0(lcd, JBT_REG_DISPLAY_ON, NULL);
247}
248
249static int td028ttec1_disable(struct drm_panel *panel)
250{
251	struct td028ttec1_panel *lcd = to_td028ttec1_device(panel);
252
253	jbt_ret_write_0(lcd, JBT_REG_DISPLAY_OFF, NULL);
254
255	return 0;
256}
257
258static int td028ttec1_unprepare(struct drm_panel *panel)
259{
260	struct td028ttec1_panel *lcd = to_td028ttec1_device(panel);
261
262	jbt_reg_write_2(lcd, JBT_REG_OUTPUT_CONTROL, 0x8002, NULL);
263	jbt_ret_write_0(lcd, JBT_REG_SLEEP_IN, NULL);
264	jbt_reg_write_1(lcd, JBT_REG_POWER_ON_OFF, 0x00, NULL);
265
266	return 0;
267}
268
269static const struct drm_display_mode td028ttec1_mode = {
270	.clock = 22153,
271	.hdisplay = 480,
272	.hsync_start = 480 + 24,
273	.hsync_end = 480 + 24 + 8,
274	.htotal = 480 + 24 + 8 + 8,
275	.vdisplay = 640,
276	.vsync_start = 640 + 4,
277	.vsync_end = 640 + 4 + 2,
278	.vtotal = 640 + 4 + 2 + 2,
279	.type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
280	.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
281	.width_mm = 43,
282	.height_mm = 58,
283};
284
285static int td028ttec1_get_modes(struct drm_panel *panel,
286				struct drm_connector *connector)
287{
288	struct drm_display_mode *mode;
289
290	mode = drm_mode_duplicate(connector->dev, &td028ttec1_mode);
291	if (!mode)
292		return -ENOMEM;
293
294	drm_mode_set_name(mode);
295	drm_mode_probed_add(connector, mode);
296
297	connector->display_info.width_mm = td028ttec1_mode.width_mm;
298	connector->display_info.height_mm = td028ttec1_mode.height_mm;
299	/*
300	 * FIXME: According to the datasheet sync signals are sampled on the
301	 * rising edge of the clock, but the code running on the OpenMoko Neo
302	 * FreeRunner and Neo 1973 indicates sampling on the falling edge. This
303	 * should be tested on a real device.
304	 */
305	connector->display_info.bus_flags = DRM_BUS_FLAG_DE_HIGH
306					  | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE
307					  | DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE;
308
309	return 1;
310}
311
312static const struct drm_panel_funcs td028ttec1_funcs = {
313	.prepare = td028ttec1_prepare,
314	.enable = td028ttec1_enable,
315	.disable = td028ttec1_disable,
316	.unprepare = td028ttec1_unprepare,
317	.get_modes = td028ttec1_get_modes,
318};
319
320static int td028ttec1_probe(struct spi_device *spi)
321{
322	struct td028ttec1_panel *lcd;
323	int ret;
324
325	lcd = devm_kzalloc(&spi->dev, sizeof(*lcd), GFP_KERNEL);
326	if (!lcd)
327		return -ENOMEM;
328
329	spi_set_drvdata(spi, lcd);
330	lcd->spi = spi;
331
332	spi->mode = SPI_MODE_3;
333	spi->bits_per_word = 9;
334
335	ret = spi_setup(spi);
336	if (ret < 0) {
337		dev_err(&spi->dev, "failed to setup SPI: %d\n", ret);
338		return ret;
339	}
340
341	drm_panel_init(&lcd->panel, &lcd->spi->dev, &td028ttec1_funcs,
342		       DRM_MODE_CONNECTOR_DPI);
343
344	ret = drm_panel_of_backlight(&lcd->panel);
345	if (ret)
346		return ret;
347
348	drm_panel_add(&lcd->panel);
349
350	return 0;
351}
352
353static void td028ttec1_remove(struct spi_device *spi)
354{
355	struct td028ttec1_panel *lcd = spi_get_drvdata(spi);
356
357	drm_panel_remove(&lcd->panel);
358	drm_panel_disable(&lcd->panel);
359	drm_panel_unprepare(&lcd->panel);
360}
361
362static const struct of_device_id td028ttec1_of_match[] = {
363	{ .compatible = "tpo,td028ttec1", },
364	/* DT backward compatibility. */
365	{ .compatible = "toppoly,td028ttec1", },
366	{ /* sentinel */ },
367};
368
369MODULE_DEVICE_TABLE(of, td028ttec1_of_match);
370
371static const struct spi_device_id td028ttec1_ids[] = {
372	{ "td028ttec1", 0 },
373	{ /* sentinel */ }
374};
375
376MODULE_DEVICE_TABLE(spi, td028ttec1_ids);
377
378static struct spi_driver td028ttec1_driver = {
379	.probe		= td028ttec1_probe,
380	.remove		= td028ttec1_remove,
381	.id_table	= td028ttec1_ids,
382	.driver		= {
383		.name   = "panel-tpo-td028ttec1",
384		.of_match_table = td028ttec1_of_match,
385	},
386};
387
388module_spi_driver(td028ttec1_driver);
389
390MODULE_AUTHOR("H. Nikolaus Schaller <hns@goldelico.com>");
391MODULE_DESCRIPTION("Toppoly TD028TTEC1 panel driver");
392MODULE_LICENSE("GPL");
393