1 /* 2 * Copyright © 2016-2017 Broadcom 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * Portions of this file (derived from panel-simple.c) are: 9 * 10 * Copyright (C) 2013, NVIDIA Corporation. All rights reserved. 11 * 12 * Permission is hereby granted, free of charge, to any person obtaining a 13 * copy of this software and associated documentation files (the "Software"), 14 * to deal in the Software without restriction, including without limitation 15 * the rights to use, copy, modify, merge, publish, distribute, sub license, 16 * and/or sell copies of the Software, and to permit persons to whom the 17 * Software is furnished to do so, subject to the following conditions: 18 * 19 * The above copyright notice and this permission notice (including the 20 * next paragraph) shall be included in all copies or substantial portions 21 * of the Software. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 24 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 25 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 26 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 27 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 28 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 29 * DEALINGS IN THE SOFTWARE. 30 */ 31 32 /* 33 * Raspberry Pi 7" touchscreen panel driver. 34 * 35 * The 7" touchscreen consists of a DPI LCD panel, a Toshiba 36 * TC358762XBG DSI-DPI bridge, and an I2C-connected Atmel ATTINY88-MUR 37 * controlling power management, the LCD PWM, and initial register 38 * setup of the Tohsiba. 39 * 40 * This driver controls the TC358762 and ATTINY88, presenting a DSI 41 * device with a drm_panel. 42 */ 43 44 #include <linux/delay.h> 45 #include <linux/err.h> 46 #include <linux/fb.h> 47 #include <linux/i2c.h> 48 #include <linux/media-bus-format.h> 49 #include <linux/module.h> 50 #include <linux/of.h> 51 #include <linux/of_device.h> 52 #include <linux/of_graph.h> 53 #include <linux/pm.h> 54 55 #include <drm/drm_crtc.h> 56 #include <drm/drm_device.h> 57 #include <drm/drm_mipi_dsi.h> 58 #include <drm/drm_panel.h> 59 60 #define RPI_DSI_DRIVER_NAME "rpi-ts-dsi" 61 62 /* I2C registers of the Atmel microcontroller. */ 63 enum REG_ADDR { 64 REG_ID = 0x80, 65 REG_PORTA, /* BIT(2) for horizontal flip, BIT(3) for vertical flip */ 66 REG_PORTB, 67 REG_PORTC, 68 REG_PORTD, 69 REG_POWERON, 70 REG_PWM, 71 REG_DDRA, 72 REG_DDRB, 73 REG_DDRC, 74 REG_DDRD, 75 REG_TEST, 76 REG_WR_ADDRL, 77 REG_WR_ADDRH, 78 REG_READH, 79 REG_READL, 80 REG_WRITEH, 81 REG_WRITEL, 82 REG_ID2, 83 }; 84 85 /* DSI D-PHY Layer Registers */ 86 #define D0W_DPHYCONTTX 0x0004 87 #define CLW_DPHYCONTRX 0x0020 88 #define D0W_DPHYCONTRX 0x0024 89 #define D1W_DPHYCONTRX 0x0028 90 #define COM_DPHYCONTRX 0x0038 91 #define CLW_CNTRL 0x0040 92 #define D0W_CNTRL 0x0044 93 #define D1W_CNTRL 0x0048 94 #define DFTMODE_CNTRL 0x0054 95 96 /* DSI PPI Layer Registers */ 97 #define PPI_STARTPPI 0x0104 98 #define PPI_BUSYPPI 0x0108 99 #define PPI_LINEINITCNT 0x0110 100 #define PPI_LPTXTIMECNT 0x0114 101 #define PPI_CLS_ATMR 0x0140 102 #define PPI_D0S_ATMR 0x0144 103 #define PPI_D1S_ATMR 0x0148 104 #define PPI_D0S_CLRSIPOCOUNT 0x0164 105 #define PPI_D1S_CLRSIPOCOUNT 0x0168 106 #define CLS_PRE 0x0180 107 #define D0S_PRE 0x0184 108 #define D1S_PRE 0x0188 109 #define CLS_PREP 0x01A0 110 #define D0S_PREP 0x01A4 111 #define D1S_PREP 0x01A8 112 #define CLS_ZERO 0x01C0 113 #define D0S_ZERO 0x01C4 114 #define D1S_ZERO 0x01C8 115 #define PPI_CLRFLG 0x01E0 116 #define PPI_CLRSIPO 0x01E4 117 #define HSTIMEOUT 0x01F0 118 #define HSTIMEOUTENABLE 0x01F4 119 120 /* DSI Protocol Layer Registers */ 121 #define DSI_STARTDSI 0x0204 122 #define DSI_BUSYDSI 0x0208 123 #define DSI_LANEENABLE 0x0210 124 # define DSI_LANEENABLE_CLOCK BIT(0) 125 # define DSI_LANEENABLE_D0 BIT(1) 126 # define DSI_LANEENABLE_D1 BIT(2) 127 128 #define DSI_LANESTATUS0 0x0214 129 #define DSI_LANESTATUS1 0x0218 130 #define DSI_INTSTATUS 0x0220 131 #define DSI_INTMASK 0x0224 132 #define DSI_INTCLR 0x0228 133 #define DSI_LPTXTO 0x0230 134 #define DSI_MODE 0x0260 135 #define DSI_PAYLOAD0 0x0268 136 #define DSI_PAYLOAD1 0x026C 137 #define DSI_SHORTPKTDAT 0x0270 138 #define DSI_SHORTPKTREQ 0x0274 139 #define DSI_BTASTA 0x0278 140 #define DSI_BTACLR 0x027C 141 142 /* DSI General Registers */ 143 #define DSIERRCNT 0x0300 144 #define DSISIGMOD 0x0304 145 146 /* DSI Application Layer Registers */ 147 #define APLCTRL 0x0400 148 #define APLSTAT 0x0404 149 #define APLERR 0x0408 150 #define PWRMOD 0x040C 151 #define RDPKTLN 0x0410 152 #define PXLFMT 0x0414 153 #define MEMWRCMD 0x0418 154 155 /* LCDC/DPI Host Registers */ 156 #define LCDCTRL 0x0420 157 #define HSR 0x0424 158 #define HDISPR 0x0428 159 #define VSR 0x042C 160 #define VDISPR 0x0430 161 #define VFUEN 0x0434 162 163 /* DBI-B Host Registers */ 164 #define DBIBCTRL 0x0440 165 166 /* SPI Master Registers */ 167 #define SPICMR 0x0450 168 #define SPITCR 0x0454 169 170 /* System Controller Registers */ 171 #define SYSSTAT 0x0460 172 #define SYSCTRL 0x0464 173 #define SYSPLL1 0x0468 174 #define SYSPLL2 0x046C 175 #define SYSPLL3 0x0470 176 #define SYSPMCTRL 0x047C 177 178 /* GPIO Registers */ 179 #define GPIOC 0x0480 180 #define GPIOO 0x0484 181 #define GPIOI 0x0488 182 183 /* I2C Registers */ 184 #define I2CCLKCTRL 0x0490 185 186 /* Chip/Rev Registers */ 187 #define IDREG 0x04A0 188 189 /* Debug Registers */ 190 #define WCMDQUEUE 0x0500 191 #define RCMDQUEUE 0x0504 192 193 struct rpi_touchscreen { 194 struct drm_panel base; 195 struct mipi_dsi_device *dsi; 196 struct i2c_client *i2c; 197 }; 198 199 static const struct drm_display_mode rpi_touchscreen_modes[] = { 200 { 201 /* Modeline comes from the Raspberry Pi firmware, with HFP=1 202 * plugged in and clock re-computed from that. 203 */ 204 .clock = 25979400 / 1000, 205 .hdisplay = 800, 206 .hsync_start = 800 + 1, 207 .hsync_end = 800 + 1 + 2, 208 .htotal = 800 + 1 + 2 + 46, 209 .vdisplay = 480, 210 .vsync_start = 480 + 7, 211 .vsync_end = 480 + 7 + 2, 212 .vtotal = 480 + 7 + 2 + 21, 213 }, 214 }; 215 216 static struct rpi_touchscreen *panel_to_ts(struct drm_panel *panel) 217 { 218 return container_of(panel, struct rpi_touchscreen, base); 219 } 220 221 static int rpi_touchscreen_i2c_read(struct rpi_touchscreen *ts, u8 reg) 222 { 223 return i2c_smbus_read_byte_data(ts->i2c, reg); 224 } 225 226 static void rpi_touchscreen_i2c_write(struct rpi_touchscreen *ts, 227 u8 reg, u8 val) 228 { 229 int ret; 230 231 ret = i2c_smbus_write_byte_data(ts->i2c, reg, val); 232 if (ret) 233 dev_err(&ts->i2c->dev, "I2C write failed: %d\n", ret); 234 } 235 236 static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val) 237 { 238 u8 msg[] = { 239 reg, 240 reg >> 8, 241 val, 242 val >> 8, 243 val >> 16, 244 val >> 24, 245 }; 246 247 mipi_dsi_generic_write(ts->dsi, msg, sizeof(msg)); 248 249 return 0; 250 } 251 252 static int rpi_touchscreen_disable(struct drm_panel *panel) 253 { 254 struct rpi_touchscreen *ts = panel_to_ts(panel); 255 256 rpi_touchscreen_i2c_write(ts, REG_PWM, 0); 257 258 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 259 udelay(1); 260 261 return 0; 262 } 263 264 static int rpi_touchscreen_noop(struct drm_panel *panel) 265 { 266 return 0; 267 } 268 269 static int rpi_touchscreen_prepare(struct drm_panel *panel) 270 { 271 struct rpi_touchscreen *ts = panel_to_ts(panel); 272 int i; 273 274 rpi_touchscreen_i2c_write(ts, REG_POWERON, 1); 275 /* Wait for nPWRDWN to go low to indicate poweron is done. */ 276 for (i = 0; i < 100; i++) { 277 if (rpi_touchscreen_i2c_read(ts, REG_PORTB) & 1) 278 break; 279 } 280 281 rpi_touchscreen_write(ts, DSI_LANEENABLE, 282 DSI_LANEENABLE_CLOCK | 283 DSI_LANEENABLE_D0); 284 rpi_touchscreen_write(ts, PPI_D0S_CLRSIPOCOUNT, 0x05); 285 rpi_touchscreen_write(ts, PPI_D1S_CLRSIPOCOUNT, 0x05); 286 rpi_touchscreen_write(ts, PPI_D0S_ATMR, 0x00); 287 rpi_touchscreen_write(ts, PPI_D1S_ATMR, 0x00); 288 rpi_touchscreen_write(ts, PPI_LPTXTIMECNT, 0x03); 289 290 rpi_touchscreen_write(ts, SPICMR, 0x00); 291 rpi_touchscreen_write(ts, LCDCTRL, 0x00100150); 292 rpi_touchscreen_write(ts, SYSCTRL, 0x040f); 293 msleep(100); 294 295 rpi_touchscreen_write(ts, PPI_STARTPPI, 0x01); 296 rpi_touchscreen_write(ts, DSI_STARTDSI, 0x01); 297 msleep(100); 298 299 return 0; 300 } 301 302 static int rpi_touchscreen_enable(struct drm_panel *panel) 303 { 304 struct rpi_touchscreen *ts = panel_to_ts(panel); 305 306 /* Turn on the backlight. */ 307 rpi_touchscreen_i2c_write(ts, REG_PWM, 255); 308 309 /* Default to the same orientation as the closed source 310 * firmware used for the panel. Runtime rotation 311 * configuration will be supported using VC4's plane 312 * orientation bits. 313 */ 314 rpi_touchscreen_i2c_write(ts, REG_PORTA, BIT(2)); 315 316 return 0; 317 } 318 319 static int rpi_touchscreen_get_modes(struct drm_panel *panel, 320 struct drm_connector *connector) 321 { 322 unsigned int i, num = 0; 323 static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24; 324 325 for (i = 0; i < ARRAY_SIZE(rpi_touchscreen_modes); i++) { 326 const struct drm_display_mode *m = &rpi_touchscreen_modes[i]; 327 struct drm_display_mode *mode; 328 329 mode = drm_mode_duplicate(connector->dev, m); 330 if (!mode) { 331 dev_err(panel->dev, "failed to add mode %ux%u@%u\n", 332 m->hdisplay, m->vdisplay, 333 drm_mode_vrefresh(m)); 334 continue; 335 } 336 337 mode->type |= DRM_MODE_TYPE_DRIVER; 338 339 if (i == 0) 340 mode->type |= DRM_MODE_TYPE_PREFERRED; 341 342 drm_mode_set_name(mode); 343 344 drm_mode_probed_add(connector, mode); 345 num++; 346 } 347 348 connector->display_info.bpc = 8; 349 connector->display_info.width_mm = 154; 350 connector->display_info.height_mm = 86; 351 drm_display_info_set_bus_formats(&connector->display_info, 352 &bus_format, 1); 353 354 return num; 355 } 356 357 static const struct drm_panel_funcs rpi_touchscreen_funcs = { 358 .disable = rpi_touchscreen_disable, 359 .unprepare = rpi_touchscreen_noop, 360 .prepare = rpi_touchscreen_prepare, 361 .enable = rpi_touchscreen_enable, 362 .get_modes = rpi_touchscreen_get_modes, 363 }; 364 365 static int rpi_touchscreen_probe(struct i2c_client *i2c) 366 { 367 struct device *dev = &i2c->dev; 368 struct rpi_touchscreen *ts; 369 struct device_node *endpoint, *dsi_host_node; 370 struct mipi_dsi_host *host; 371 int ver; 372 struct mipi_dsi_device_info info = { 373 .type = RPI_DSI_DRIVER_NAME, 374 .channel = 0, 375 .node = NULL, 376 }; 377 378 ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); 379 if (!ts) 380 return -ENOMEM; 381 382 i2c_set_clientdata(i2c, ts); 383 384 ts->i2c = i2c; 385 386 ver = rpi_touchscreen_i2c_read(ts, REG_ID); 387 if (ver < 0) { 388 dev_err(dev, "Atmel I2C read failed: %d\n", ver); 389 return -ENODEV; 390 } 391 392 switch (ver) { 393 case 0xde: /* ver 1 */ 394 case 0xc3: /* ver 2 */ 395 break; 396 default: 397 dev_err(dev, "Unknown Atmel firmware revision: 0x%02x\n", ver); 398 return -ENODEV; 399 } 400 401 /* Turn off at boot, so we can cleanly sequence powering on. */ 402 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 403 404 /* Look up the DSI host. It needs to probe before we do. */ 405 endpoint = of_graph_get_next_endpoint(dev->of_node, NULL); 406 if (!endpoint) 407 return -ENODEV; 408 409 dsi_host_node = of_graph_get_remote_port_parent(endpoint); 410 if (!dsi_host_node) 411 goto error; 412 413 host = of_find_mipi_dsi_host_by_node(dsi_host_node); 414 of_node_put(dsi_host_node); 415 if (!host) { 416 of_node_put(endpoint); 417 return -EPROBE_DEFER; 418 } 419 420 info.node = of_graph_get_remote_port(endpoint); 421 if (!info.node) 422 goto error; 423 424 of_node_put(endpoint); 425 426 ts->dsi = mipi_dsi_device_register_full(host, &info); 427 if (IS_ERR(ts->dsi)) { 428 dev_err(dev, "DSI device registration failed: %ld\n", 429 PTR_ERR(ts->dsi)); 430 return PTR_ERR(ts->dsi); 431 } 432 433 drm_panel_init(&ts->base, dev, &rpi_touchscreen_funcs, 434 DRM_MODE_CONNECTOR_DSI); 435 436 /* This appears last, as it's what will unblock the DSI host 437 * driver's component bind function. 438 */ 439 drm_panel_add(&ts->base); 440 441 return 0; 442 443 error: 444 of_node_put(endpoint); 445 return -ENODEV; 446 } 447 448 static void rpi_touchscreen_remove(struct i2c_client *i2c) 449 { 450 struct rpi_touchscreen *ts = i2c_get_clientdata(i2c); 451 452 mipi_dsi_detach(ts->dsi); 453 454 drm_panel_remove(&ts->base); 455 456 mipi_dsi_device_unregister(ts->dsi); 457 } 458 459 static int rpi_touchscreen_dsi_probe(struct mipi_dsi_device *dsi) 460 { 461 int ret; 462 463 dsi->mode_flags = (MIPI_DSI_MODE_VIDEO | 464 MIPI_DSI_MODE_VIDEO_SYNC_PULSE | 465 MIPI_DSI_MODE_LPM); 466 dsi->format = MIPI_DSI_FMT_RGB888; 467 dsi->lanes = 1; 468 469 ret = mipi_dsi_attach(dsi); 470 471 if (ret) 472 dev_err(&dsi->dev, "failed to attach dsi to host: %d\n", ret); 473 474 return ret; 475 } 476 477 static struct mipi_dsi_driver rpi_touchscreen_dsi_driver = { 478 .driver.name = RPI_DSI_DRIVER_NAME, 479 .probe = rpi_touchscreen_dsi_probe, 480 }; 481 482 static const struct of_device_id rpi_touchscreen_of_ids[] = { 483 { .compatible = "raspberrypi,7inch-touchscreen-panel" }, 484 { } /* sentinel */ 485 }; 486 MODULE_DEVICE_TABLE(of, rpi_touchscreen_of_ids); 487 488 static struct i2c_driver rpi_touchscreen_driver = { 489 .driver = { 490 .name = "rpi_touchscreen", 491 .of_match_table = rpi_touchscreen_of_ids, 492 }, 493 .probe_new = rpi_touchscreen_probe, 494 .remove = rpi_touchscreen_remove, 495 }; 496 497 static int __init rpi_touchscreen_init(void) 498 { 499 mipi_dsi_driver_register(&rpi_touchscreen_dsi_driver); 500 return i2c_add_driver(&rpi_touchscreen_driver); 501 } 502 module_init(rpi_touchscreen_init); 503 504 static void __exit rpi_touchscreen_exit(void) 505 { 506 i2c_del_driver(&rpi_touchscreen_driver); 507 mipi_dsi_driver_unregister(&rpi_touchscreen_dsi_driver); 508 } 509 module_exit(rpi_touchscreen_exit); 510 511 MODULE_AUTHOR("Eric Anholt <eric@anholt.net>"); 512 MODULE_DESCRIPTION("Raspberry Pi 7-inch touchscreen driver"); 513 MODULE_LICENSE("GPL v2"); 514