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/mod_devicetable.h>
15 #include <linux/module.h>
16 #include <linux/of_graph.h>
17 #include <linux/regulator/consumer.h>
18
19 #include <video/mipi_display.h>
20
21 #include <drm/drm_atomic_helper.h>
22 #include <drm/drm_crtc.h>
23 #include <drm/drm_mipi_dsi.h>
24 #include <drm/drm_of.h>
25 #include <drm/drm_panel.h>
26 #include <drm/drm_print.h>
27 #include <drm/drm_probe_helper.h>
28
29 /* PPI layer registers */
30 #define PPI_STARTPPI 0x0104 /* START control bit */
31 #define PPI_LPTXTIMECNT 0x0114 /* LPTX timing signal */
32 #define PPI_D0S_ATMR 0x0144
33 #define PPI_D1S_ATMR 0x0148
34 #define PPI_D0S_CLRSIPOCOUNT 0x0164 /* Assertion timer for Lane 0 */
35 #define PPI_D1S_CLRSIPOCOUNT 0x0168 /* Assertion timer for Lane 1 */
36 #define PPI_START_FUNCTION 1
37
38 /* DSI layer registers */
39 #define DSI_STARTDSI 0x0204 /* START control bit of DSI-TX */
40 #define DSI_LANEENABLE 0x0210 /* Enables each lane */
41 #define DSI_RX_START 1
42
43 /* LCDC/DPI Host Registers */
44 #define LCDCTRL 0x0420
45
46 /* SPI Master Registers */
47 #define SPICMR 0x0450
48 #define SPITCR 0x0454
49
50 /* System Controller Registers */
51 #define SYSCTRL 0x0464
52
53 /* System registers */
54 #define LPX_PERIOD 3
55
56 /* Lane enable PPI and DSI register bits */
57 #define LANEENABLE_CLEN BIT(0)
58 #define LANEENABLE_L0EN BIT(1)
59 #define LANEENABLE_L1EN BIT(2)
60
61 struct tc358762 {
62 struct device *dev;
63 struct drm_bridge bridge;
64 struct regulator *regulator;
65 struct drm_bridge *panel_bridge;
66 bool pre_enabled;
67 int error;
68 };
69
tc358762_clear_error(struct tc358762 * ctx)70 static int tc358762_clear_error(struct tc358762 *ctx)
71 {
72 int ret = ctx->error;
73
74 ctx->error = 0;
75 return ret;
76 }
77
tc358762_write(struct tc358762 * ctx,u16 addr,u32 val)78 static void tc358762_write(struct tc358762 *ctx, u16 addr, u32 val)
79 {
80 struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
81 ssize_t ret;
82 u8 data[6];
83
84 if (ctx->error)
85 return;
86
87 data[0] = addr;
88 data[1] = addr >> 8;
89 data[2] = val;
90 data[3] = val >> 8;
91 data[4] = val >> 16;
92 data[5] = val >> 24;
93
94 ret = mipi_dsi_generic_write(dsi, data, sizeof(data));
95 if (ret < 0)
96 ctx->error = ret;
97 }
98
bridge_to_tc358762(struct drm_bridge * bridge)99 static inline struct tc358762 *bridge_to_tc358762(struct drm_bridge *bridge)
100 {
101 return container_of(bridge, struct tc358762, bridge);
102 }
103
tc358762_init(struct tc358762 * ctx)104 static int tc358762_init(struct tc358762 *ctx)
105 {
106 tc358762_write(ctx, DSI_LANEENABLE,
107 LANEENABLE_L0EN | LANEENABLE_CLEN);
108 tc358762_write(ctx, PPI_D0S_CLRSIPOCOUNT, 5);
109 tc358762_write(ctx, PPI_D1S_CLRSIPOCOUNT, 5);
110 tc358762_write(ctx, PPI_D0S_ATMR, 0);
111 tc358762_write(ctx, PPI_D1S_ATMR, 0);
112 tc358762_write(ctx, PPI_LPTXTIMECNT, LPX_PERIOD);
113
114 tc358762_write(ctx, SPICMR, 0x00);
115 tc358762_write(ctx, LCDCTRL, 0x00100150);
116 tc358762_write(ctx, SYSCTRL, 0x040f);
117 msleep(100);
118
119 tc358762_write(ctx, PPI_STARTPPI, PPI_START_FUNCTION);
120 tc358762_write(ctx, DSI_STARTDSI, DSI_RX_START);
121
122 msleep(100);
123
124 return tc358762_clear_error(ctx);
125 }
126
tc358762_post_disable(struct drm_bridge * bridge)127 static void tc358762_post_disable(struct drm_bridge *bridge)
128 {
129 struct tc358762 *ctx = bridge_to_tc358762(bridge);
130 int ret;
131
132 /*
133 * The post_disable hook might be called multiple times.
134 * We want to avoid regulator imbalance below.
135 */
136 if (!ctx->pre_enabled)
137 return;
138
139 ctx->pre_enabled = false;
140
141 ret = regulator_disable(ctx->regulator);
142 if (ret < 0)
143 dev_err(ctx->dev, "error disabling regulators (%d)\n", ret);
144 }
145
tc358762_pre_enable(struct drm_bridge * bridge)146 static void tc358762_pre_enable(struct drm_bridge *bridge)
147 {
148 struct tc358762 *ctx = bridge_to_tc358762(bridge);
149 int ret;
150
151 ret = regulator_enable(ctx->regulator);
152 if (ret < 0)
153 dev_err(ctx->dev, "error enabling regulators (%d)\n", ret);
154
155 ret = tc358762_init(ctx);
156 if (ret < 0)
157 dev_err(ctx->dev, "error initializing bridge (%d)\n", ret);
158
159 ctx->pre_enabled = true;
160 }
161
tc358762_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)162 static int tc358762_attach(struct drm_bridge *bridge,
163 enum drm_bridge_attach_flags flags)
164 {
165 struct tc358762 *ctx = bridge_to_tc358762(bridge);
166
167 return drm_bridge_attach(bridge->encoder, ctx->panel_bridge,
168 bridge, flags);
169 }
170
171 static const struct drm_bridge_funcs tc358762_bridge_funcs = {
172 .post_disable = tc358762_post_disable,
173 .pre_enable = tc358762_pre_enable,
174 .attach = tc358762_attach,
175 };
176
tc358762_parse_dt(struct tc358762 * ctx)177 static int tc358762_parse_dt(struct tc358762 *ctx)
178 {
179 struct drm_bridge *panel_bridge;
180 struct device *dev = ctx->dev;
181
182 panel_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);
183 if (IS_ERR(panel_bridge))
184 return PTR_ERR(panel_bridge);
185
186 ctx->panel_bridge = panel_bridge;
187
188 return 0;
189 }
190
tc358762_configure_regulators(struct tc358762 * ctx)191 static int tc358762_configure_regulators(struct tc358762 *ctx)
192 {
193 ctx->regulator = devm_regulator_get(ctx->dev, "vddc");
194 if (IS_ERR(ctx->regulator))
195 return PTR_ERR(ctx->regulator);
196
197 return 0;
198 }
199
tc358762_probe(struct mipi_dsi_device * dsi)200 static int tc358762_probe(struct mipi_dsi_device *dsi)
201 {
202 struct device *dev = &dsi->dev;
203 struct tc358762 *ctx;
204 int ret;
205
206 ctx = devm_kzalloc(dev, sizeof(struct tc358762), GFP_KERNEL);
207 if (!ctx)
208 return -ENOMEM;
209
210 mipi_dsi_set_drvdata(dsi, ctx);
211
212 ctx->dev = dev;
213 ctx->pre_enabled = false;
214
215 /* TODO: Find out how to get dual-lane mode working */
216 dsi->lanes = 1;
217 dsi->format = MIPI_DSI_FMT_RGB888;
218 dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_SYNC_PULSE |
219 MIPI_DSI_MODE_LPM;
220
221 ret = tc358762_parse_dt(ctx);
222 if (ret < 0)
223 return ret;
224
225 ret = tc358762_configure_regulators(ctx);
226 if (ret < 0)
227 return ret;
228
229 ctx->bridge.funcs = &tc358762_bridge_funcs;
230 ctx->bridge.type = DRM_MODE_CONNECTOR_DPI;
231 ctx->bridge.of_node = dev->of_node;
232
233 drm_bridge_add(&ctx->bridge);
234
235 ret = mipi_dsi_attach(dsi);
236 if (ret < 0) {
237 drm_bridge_remove(&ctx->bridge);
238 dev_err(dev, "failed to attach dsi\n");
239 }
240
241 return ret;
242 }
243
tc358762_remove(struct mipi_dsi_device * dsi)244 static void tc358762_remove(struct mipi_dsi_device *dsi)
245 {
246 struct tc358762 *ctx = mipi_dsi_get_drvdata(dsi);
247
248 mipi_dsi_detach(dsi);
249 drm_bridge_remove(&ctx->bridge);
250 }
251
252 static const struct of_device_id tc358762_of_match[] = {
253 { .compatible = "toshiba,tc358762" },
254 { }
255 };
256 MODULE_DEVICE_TABLE(of, tc358762_of_match);
257
258 static struct mipi_dsi_driver tc358762_driver = {
259 .probe = tc358762_probe,
260 .remove = tc358762_remove,
261 .driver = {
262 .name = "tc358762",
263 .of_match_table = tc358762_of_match,
264 },
265 };
266 module_mipi_dsi_driver(tc358762_driver);
267
268 MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
269 MODULE_DESCRIPTION("MIPI-DSI based Driver for TC358762 DSI/DPI Bridge");
270 MODULE_LICENSE("GPL v2");
271