1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2020 Marek Vasut <marex@denx.de>
4 *
5 * Based on tc358764.c by
6 * Andrzej Hajda <a.hajda@samsung.com>
7 * Maciej Purski <m.purski@samsung.com>
8 *
9 * Based on rpi_touchscreen.c by
10 * Eric Anholt <eric@anholt.net>
11 */
12
13#include <linux/delay.h>
14#include <linux/gpio/consumer.h>
15#include <linux/mod_devicetable.h>
16#include <linux/module.h>
17#include <linux/of_graph.h>
18#include <linux/regulator/consumer.h>
19
20#include <video/mipi_display.h>
21
22#include <drm/drm_atomic_helper.h>
23#include <drm/drm_crtc.h>
24#include <drm/drm_mipi_dsi.h>
25#include <drm/drm_of.h>
26#include <drm/drm_panel.h>
27#include <drm/drm_print.h>
28#include <drm/drm_probe_helper.h>
29
30/* PPI layer registers */
31#define PPI_STARTPPI 0x0104 /* START control bit */
32#define PPI_LPTXTIMECNT 0x0114 /* LPTX timing signal */
33#define PPI_D0S_ATMR 0x0144
34#define PPI_D1S_ATMR 0x0148
35#define PPI_D0S_CLRSIPOCOUNT 0x0164 /* Assertion timer for Lane 0 */
36#define PPI_D1S_CLRSIPOCOUNT 0x0168 /* Assertion timer for Lane 1 */
37#define PPI_START_FUNCTION 1
38
39/* DSI layer registers */
40#define DSI_STARTDSI 0x0204 /* START control bit of DSI-TX */
41#define DSI_LANEENABLE 0x0210 /* Enables each lane */
42#define DSI_RX_START 1
43
44/* LCDC/DPI Host Registers, based on guesswork that this matches TC358764 */
45#define LCDCTRL 0x0420 /* Video Path Control */
46#define LCDCTRL_MSF BIT(0) /* Magic square in RGB666 */
47#define LCDCTRL_VTGEN BIT(4)/* Use chip clock for timing */
48#define LCDCTRL_UNK6 BIT(6) /* Unknown */
49#define LCDCTRL_EVTMODE BIT(5) /* Event mode */
50#define LCDCTRL_RGB888 BIT(8) /* RGB888 mode */
51#define LCDCTRL_HSPOL BIT(17) /* Polarity of HSYNC signal */
52#define LCDCTRL_DEPOL BIT(18) /* Polarity of DE signal */
53#define LCDCTRL_VSPOL BIT(19) /* Polarity of VSYNC signal */
54#define LCDCTRL_VSDELAY(v) (((v) & 0xfff) << 20) /* VSYNC delay */
55
56/* SPI Master Registers */
57#define SPICMR 0x0450
58#define SPITCR 0x0454
59
60/* System Controller Registers */
61#define SYSCTRL 0x0464
62
63/* System registers */
64#define LPX_PERIOD 3
65
66/* Lane enable PPI and DSI register bits */
67#define LANEENABLE_CLEN BIT(0)
68#define LANEENABLE_L0EN BIT(1)
69#define LANEENABLE_L1EN BIT(2)
70
71struct tc358762 {
72 struct device *dev;
73 struct drm_bridge bridge;
74 struct regulator *regulator;
75 struct drm_bridge *panel_bridge;
76 struct gpio_desc *reset_gpio;
77 struct drm_display_mode mode;
78 bool pre_enabled;
79 int error;
80};
81
82static int tc358762_clear_error(struct tc358762 *ctx)
83{
84 int ret = ctx->error;
85
86 ctx->error = 0;
87 return ret;
88}
89
90static void tc358762_write(struct tc358762 *ctx, u16 addr, u32 val)
91{
92 struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
93 ssize_t ret;
94 u8 data[6];
95
96 if (ctx->error)
97 return;
98
99 data[0] = addr;
100 data[1] = addr >> 8;
101 data[2] = val;
102 data[3] = val >> 8;
103 data[4] = val >> 16;
104 data[5] = val >> 24;
105
106 ret = mipi_dsi_generic_write(dsi, payload: data, size: sizeof(data));
107 if (ret < 0)
108 ctx->error = ret;
109}
110
111static inline struct tc358762 *bridge_to_tc358762(struct drm_bridge *bridge)
112{
113 return container_of(bridge, struct tc358762, bridge);
114}
115
116static int tc358762_init(struct tc358762 *ctx)
117{
118 u32 lcdctrl;
119
120 tc358762_write(ctx, DSI_LANEENABLE,
121 LANEENABLE_L0EN | LANEENABLE_CLEN);
122 tc358762_write(ctx, PPI_D0S_CLRSIPOCOUNT, val: 5);
123 tc358762_write(ctx, PPI_D1S_CLRSIPOCOUNT, val: 5);
124 tc358762_write(ctx, PPI_D0S_ATMR, val: 0);
125 tc358762_write(ctx, PPI_D1S_ATMR, val: 0);
126 tc358762_write(ctx, PPI_LPTXTIMECNT, LPX_PERIOD);
127
128 tc358762_write(ctx, SPICMR, val: 0x00);
129
130 lcdctrl = LCDCTRL_VSDELAY(1) | LCDCTRL_RGB888 |
131 LCDCTRL_UNK6 | LCDCTRL_VTGEN;
132
133 if (ctx->mode.flags & DRM_MODE_FLAG_NHSYNC)
134 lcdctrl |= LCDCTRL_HSPOL;
135
136 if (ctx->mode.flags & DRM_MODE_FLAG_NVSYNC)
137 lcdctrl |= LCDCTRL_VSPOL;
138
139 tc358762_write(ctx, LCDCTRL, val: lcdctrl);
140
141 tc358762_write(ctx, SYSCTRL, val: 0x040f);
142 msleep(msecs: 100);
143
144 tc358762_write(ctx, PPI_STARTPPI, PPI_START_FUNCTION);
145 tc358762_write(ctx, DSI_STARTDSI, DSI_RX_START);
146
147 msleep(msecs: 100);
148
149 return tc358762_clear_error(ctx);
150}
151
152static void tc358762_post_disable(struct drm_bridge *bridge, struct drm_bridge_state *state)
153{
154 struct tc358762 *ctx = bridge_to_tc358762(bridge);
155 int ret;
156
157 /*
158 * The post_disable hook might be called multiple times.
159 * We want to avoid regulator imbalance below.
160 */
161 if (!ctx->pre_enabled)
162 return;
163
164 ctx->pre_enabled = false;
165
166 if (ctx->reset_gpio)
167 gpiod_set_value_cansleep(desc: ctx->reset_gpio, value: 0);
168
169 ret = regulator_disable(regulator: ctx->regulator);
170 if (ret < 0)
171 dev_err(ctx->dev, "error disabling regulators (%d)\n", ret);
172}
173
174static void tc358762_pre_enable(struct drm_bridge *bridge, struct drm_bridge_state *state)
175{
176 struct tc358762 *ctx = bridge_to_tc358762(bridge);
177 int ret;
178
179 ret = regulator_enable(regulator: ctx->regulator);
180 if (ret < 0)
181 dev_err(ctx->dev, "error enabling regulators (%d)\n", ret);
182
183 if (ctx->reset_gpio) {
184 gpiod_set_value_cansleep(desc: ctx->reset_gpio, value: 1);
185 usleep_range(min: 5000, max: 10000);
186 }
187
188 ctx->pre_enabled = true;
189}
190
191static void tc358762_enable(struct drm_bridge *bridge, struct drm_bridge_state *state)
192{
193 struct tc358762 *ctx = bridge_to_tc358762(bridge);
194 int ret;
195
196 ret = tc358762_init(ctx);
197 if (ret < 0)
198 dev_err(ctx->dev, "error initializing bridge (%d)\n", ret);
199}
200
201static int tc358762_attach(struct drm_bridge *bridge,
202 enum drm_bridge_attach_flags flags)
203{
204 struct tc358762 *ctx = bridge_to_tc358762(bridge);
205
206 return drm_bridge_attach(encoder: bridge->encoder, bridge: ctx->panel_bridge,
207 previous: bridge, flags);
208}
209
210static void tc358762_bridge_mode_set(struct drm_bridge *bridge,
211 const struct drm_display_mode *mode,
212 const struct drm_display_mode *adj)
213{
214 struct tc358762 *ctx = bridge_to_tc358762(bridge);
215
216 drm_mode_copy(dst: &ctx->mode, src: mode);
217}
218
219static const struct drm_bridge_funcs tc358762_bridge_funcs = {
220 .atomic_post_disable = tc358762_post_disable,
221 .atomic_pre_enable = tc358762_pre_enable,
222 .atomic_enable = tc358762_enable,
223 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
224 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
225 .atomic_reset = drm_atomic_helper_bridge_reset,
226 .attach = tc358762_attach,
227 .mode_set = tc358762_bridge_mode_set,
228};
229
230static int tc358762_parse_dt(struct tc358762 *ctx)
231{
232 struct drm_bridge *panel_bridge;
233 struct device *dev = ctx->dev;
234
235 panel_bridge = devm_drm_of_get_bridge(dev, node: dev->of_node, port: 1, endpoint: 0);
236 if (IS_ERR(ptr: panel_bridge))
237 return PTR_ERR(ptr: panel_bridge);
238
239 ctx->panel_bridge = panel_bridge;
240
241 /* Reset GPIO is optional */
242 ctx->reset_gpio = devm_gpiod_get_optional(dev, con_id: "reset", flags: GPIOD_OUT_LOW);
243 if (IS_ERR(ptr: ctx->reset_gpio))
244 return PTR_ERR(ptr: ctx->reset_gpio);
245
246 return 0;
247}
248
249static int tc358762_configure_regulators(struct tc358762 *ctx)
250{
251 ctx->regulator = devm_regulator_get(dev: ctx->dev, id: "vddc");
252 if (IS_ERR(ptr: ctx->regulator))
253 return PTR_ERR(ptr: ctx->regulator);
254
255 return 0;
256}
257
258static int tc358762_probe(struct mipi_dsi_device *dsi)
259{
260 struct device *dev = &dsi->dev;
261 struct tc358762 *ctx;
262 int ret;
263
264 ctx = devm_kzalloc(dev, size: sizeof(struct tc358762), GFP_KERNEL);
265 if (!ctx)
266 return -ENOMEM;
267
268 mipi_dsi_set_drvdata(dsi, data: ctx);
269
270 ctx->dev = dev;
271 ctx->pre_enabled = false;
272
273 /* TODO: Find out how to get dual-lane mode working */
274 dsi->lanes = 1;
275 dsi->format = MIPI_DSI_FMT_RGB888;
276 dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_SYNC_PULSE |
277 MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_VIDEO_HSE;
278
279 ret = tc358762_parse_dt(ctx);
280 if (ret < 0)
281 return ret;
282
283 ret = tc358762_configure_regulators(ctx);
284 if (ret < 0)
285 return ret;
286
287 ctx->bridge.funcs = &tc358762_bridge_funcs;
288 ctx->bridge.type = DRM_MODE_CONNECTOR_DPI;
289 ctx->bridge.of_node = dev->of_node;
290 ctx->bridge.pre_enable_prev_first = true;
291
292 drm_bridge_add(bridge: &ctx->bridge);
293
294 ret = mipi_dsi_attach(dsi);
295 if (ret < 0) {
296 drm_bridge_remove(bridge: &ctx->bridge);
297 dev_err(dev, "failed to attach dsi\n");
298 }
299
300 return ret;
301}
302
303static void tc358762_remove(struct mipi_dsi_device *dsi)
304{
305 struct tc358762 *ctx = mipi_dsi_get_drvdata(dsi);
306
307 mipi_dsi_detach(dsi);
308 drm_bridge_remove(bridge: &ctx->bridge);
309}
310
311static const struct of_device_id tc358762_of_match[] = {
312 { .compatible = "toshiba,tc358762" },
313 { }
314};
315MODULE_DEVICE_TABLE(of, tc358762_of_match);
316
317static struct mipi_dsi_driver tc358762_driver = {
318 .probe = tc358762_probe,
319 .remove = tc358762_remove,
320 .driver = {
321 .name = "tc358762",
322 .of_match_table = tc358762_of_match,
323 },
324};
325module_mipi_dsi_driver(tc358762_driver);
326
327MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
328MODULE_DESCRIPTION("MIPI-DSI based Driver for TC358762 DSI/DPI Bridge");
329MODULE_LICENSE("GPL v2");
330

source code of linux/drivers/gpu/drm/bridge/tc358762.c